The Winter Whale

by Sarah Boessenecker (@tetrameryx)

It seems like December has become a month of basilosaurid whales – in December of 2019, we finished cleaning up, adding 3D prints of missing elements, painting, and hanging our cast basilosaurid whale of Dorudon atrox, affectionately known as ‘Manaia.” This past December, we had yet another basilosaurid whale – this one was fossil rather than a cast, and still in the ground!

 

DAY 1 (November 18, 2020)

CCNHM was invited by Rich Familia into the Giant Cement Company’s quarry outside of Harleyville, South Carolina in mid-November. This quarry exposes the late Eocene Harleyville Formation, Parker’s Ferry Formation, and Pregnall member of the Tupelo Bay Formation (formally called the Santee Limestone). We expected to just find mainly shark teeth, and possibly some archaeocete material (like a tooth, or maybe a periotic). Museum staff (Collections Manager Sarah Boessenecker, Curator Dr. Scott Persons, and Research Fellow Dr. Robert Boessenecker) were accompanied by Rich Familia, Jordy Wolfe, and Mark Bunce as they went into the field for a relaxing day of  surface collecting. We only had a couple of hours out there and the sun was setting soon, when Mark found something halfway down the slope – it was 2 partial earbones (tympanic bullae)! We got excited – Dr. Boessenecker had been hoping to find some archaeocete material – and he really, really, really likes earbones of whales! Having left and right earbones surely indicated the presence of a skull. As we went over to take a look at what he found, we saw more float* and realized there was much more than just ear bones – after about forty minutes we had identified vertebrae and what appeared to be a part of a mandible. We marked the spot, and left for the day – it’s no good trying to dig when it’s getting dark (that’s when mistakes are made!) We regrouped at their vehicles, and made a plan to come back earlier the next day and see what they could uncover.

*Bits of bone eroded out of the ground and scattered over the surface are called “float” by paleontologists – tracing the float up the slope often leads you to the source of the fragments, hopefully a skeleton still remaining in the rock.

Isurus precursor tooth found by CCNHM crew.

Dusk approaching, shortly before Mark discovered some ear bones and other float.

 

DAY 2 (November 19, 2020)

The next morning the same crew came back to the quarry, and added a new member –  Ashby Gale joined us late in the afternoon. Rather than prospecting the rest of the quarry, we all went straight for the bone float Mark had found, and set to work digging and uncovering what was below the rock surface. We carefully uncovered bone bit by bit, and confirmed the flat bone we found the prior evening was part of a left mandible. Sarah worked on uncovering a bit more of the mandible to see how complete it was – and found teeth, still in their sockets! Not only that, but the mandible seems to be nearly complete.

The jaw before Sarah cleaned it off a little more.

A beautiful jaw, with teeth still in place.

The big day where they learned what animal they were uncovering – a BABY Chrysocetus! Sarah’s hand for scale.

Such a find was amazing to see uncovered in the field, but it also let us identify the exact whale it belonged to. Basilosaurus cetoides, Dorudon serratus, and Chrysocetus healeyorum are all known from the late Eocene, so we knew it would most likely be one of these three whales they were working with. However, upon looking at the teeth Sarah uncovered, Dr. B was immediately able to recognize which animal we were working on. The whale in the ground is Chrysocetus healeyorum – the smallest of these 3 whales, which was a positive for us – it would be much easier to dig out of the ground and take into the museum.

We team continued working through the day, uncovering the whale bit-by-bit. As the day wore on and the sun got lower in the sky, Dr. B grew concerned – this skeleton kept growing. As we were digging a trench around the mandible, more and more bone was being discovered – this was turning out to be more of a skeleton, rather than an isolated jaw. The sun was setting, and the temperature was dropping – so we quickly slapped on some small plaster patch-like jackets onto the exposed clusters of bone and covered everything with a tarp, unsure of when schedules would allow for our return to continue the excavation.

Dr. Boessenecker assessing the situation.

The crew came back the next morning to poke around at the bone fragments Mark found; they quickly uncovered some articulated vertebrae, leading them to believe they had more of a skeleton than just bits of skull.

The articulated vertebrae after a bit more exposed.

L to R: Rich Familia, Mark Bunce, and Dr. B working to see how much was buried in the rock.

 

DAY 3 (November 22, 2020)

We were able to return on the following Sunday, when there was no active work in the quarry by mining equipment. Rich, Dr. Persons, Ashby, the Boesseneckers, and Jordy were all set to see how much they could uncover with a smaller crew – not everyone would be able to stay the entire day this time. Rich continued working on some associated, but isolated vertebrae near the skeleton – these became affectionately known as “Rich’s lumps” to the crew to differentiate what different projects were happening at the excavation. As they were slightly separated from the main skeletal elements, Rich was able to trench completely around them so they could undercut and jacket them for removal. By the end of the day, we had completed one major goal: completing a plaster jacket to cover up the largest bone cluster that could not be subdivided – a rather large 5×4 foot wide triangular block. We again covered everything with a tarp, as it was Thanksgiving week and the holiday meant it would likely be more than a week before they were able to return.

Rich working on exposing one of his vertebrae mounds, that became affectionately known as “Rich’s lumps.”

Rich and Mark both working.

Mark working to find the limits of the exposure, to begin trenching.

Vertebrae accidentally trenched through; there was so much bone it was impossible to know if one would be in the way while using a pick axe to trench!

Those same vertebrae accidentally trenched through.

 

DAY 4 (December 3, 2020)

We came back on December 3rd to assess the excavation – luckily, the tarp held and kept (some) of the water from the heavy rains out of the pit – kind of. The bones didn’t wash away, which was the important part – it just meant we had to go back to digging more trenches to get rid of some of the excess water. We took turns using their giant pick-ax, making trenches to divert much of the water to make work easier, and bailed out the pooled water that had collected (much of the water was from the fact that the quarry sits on top of a giant aquifer, so water was constantly seeping in). We quickly realized they would not be removing the skeleton this day – the more we tried to trench around the exposed elements, the more bone we discovered. The skeleton just kept growing. Knowing we wouldn’t be able to come back for a few days again (those pesky jobs getting in the way of things) we made a top jacket to cover the exposed elements. We laid down wetted paper towel to act as a separator, and then dipped burlap strips into plaster of paris and laid them on top of the paper towel – this took quite a lot of burlap and plaster, as we extended as far out as they could since it wasn’t possible to trench through the middle of the block – there was just too much bone to safely make the block much smaller! We laid 3 2x4s across the top of the jacket in an a-frame, and fixed them in place with burlap strips and plaster – these were to help strengthen this massive jacket along its long axis.The plaster would cure to a hard shell and protect the bones from the elements; we placed the tarp back over and called it a  day, as the sun was once again setting, making fieldwork not possible. There were 3 smaller partial jackets we were able to remove though – Rich’s lumps. We made partial jackets of these, and left the tops uncovered – they were small enough to hand-carry out of the quarry.

Dr. B digging another trench; luckily, no bone was found during this trenching.

The team worked to make a top jacket for the bones uncovered, to keep safe until their return.

They also continued to trench around the bone scatter.

Leaving the quarry late always treated the crew to beautiful sunsets.

 

DAY 5 (December 8, 2020)

We came back on December 8th, determined to finish the excavation.

Spoiler: we did not complete the excavation, but made excellent progress!

The plaster caps held over the weekend, and we set to work, trenching (again – water was a constant battle at this site) and got to work. While this plaster was curing, we began to pedestal the jacket – this is when they undercut the sediment along the bottom of the jacket, narrowing the support to make it easier to break away and flip. This is a back-breaking task – luckily, we had a ton of help this day to make it go quickly as people could trade off and work in shifts, and multiple people working on the jacket at a time, as it was so large they all fit. We also were able to use a reciprocating saw – which cut through the soft limestone like butter, and was so much faster than hammer and chisel! As we exposed more along the bottom of the jacket from undercutting, we added more burlap strips with plaster, to keep the bottom from falling out.

The a-frame for support.

Mixing more plaster.

Wrapping burlap strips/plaster along the underside of the jacket to prepare for pedestaling.

Dipping burlap strips in plaster.

Using the last of the plaster made in this batch to smooth out the jacket – plaster dries hard and when there’s ridges they can be sharp enough to slice skin! Adding the last of the plaster makes for a smooth jacket.

Once the jacket was on enough of a pedestal and the plaster had cured, there was very little rock left supporting it – meaning it didn’t take a huge amount of work to flip! We used crowbars and were able to pry it off it’s rocky pedestal, and used moving straps to gently let it down as we flipped it. Success! The jacket was flipped safely, and no bone was left behind underneath it – we had successfully dug down low enough below the bone later to not leave anything behind and no damage done to the fossil. We knew we didn’t have the manpower to get the jacket out on our own – we would need to take Rich up on his suggestion/offer of getting the heavy mine equipment in to help with that. However, we needed to complete this jacket – but removing some of the excess rock off the bottom (now top) to help lighten it and make preparation easier. We used the reciprocating saw to cut a grid into the matrix, and then used chisels and hammers to remove small blocks of sediment – this probably removed at least 150-200 pounds of sediment from the block! Once we had shaved off a good bit of the matrix, we were able to plaster the remaining area, thus sealing the fossil in a complete jacket. We knew we would be able to remove it when Rich had talked to the contract construction workers to get their help – in the meantime, we set our sights on finishing up the smaller partial jackets we had made. Once again, easier said than done; as we began trenching to pedestal these smaller bone groupings, more fossils were exposed. We were working against the clock again – the sun was getting lower, but we were determined to get these jackets pedastled, flipped, and completed. As they were too heavy to carry out by hand, they were placed next to the giant jacket – they would be transported to their vehicles with heavy machinery from the mine.

Skylar working to expose more of the right mandible found while trenching.

Josh getting absolutely covered in mud (in the name of science) using a reciprocating saw to remove matrix and undercut the jacket.

Matt trenching to removing ponding water (again.)

Using a combination of a drill with long masonry bits and a reciprocating saw, the jacket was pedestaled quickly!

Dr. B with the saw.

Ready to flip!

Moving straps were used to haul this massive jacket out of the pit – long 2x4s were laid down to use as a ramp.

This was HEAVY! It took 4-5 people pushing it up the ramp, and 2-3 people holding the ramp in place and pulling the moving straps.

Success! It was out of the pit.

The broken bit of 2×4 that made an impressive CRACK when it broke, and the pit we removed the jacket from.

Using the reciprocating saw to made a grid pattern to remove as much sediment as possible from the ‘bottom’ of the jacket – these blocks were chiseled out with a hammer and chisel and lightened the jacket by ~150-200 lbs!

day 4 After excess sediment was removed, paper towel was laid down as a separator, and then more burlap and plaster was applied to complete the jacket.

 

DAY 6 (December 15, 2020)

The day was finally here – the jackets were going to be lifted out of the quarry! We arrived on December 15th – it was by far the worst conditions we had experienced in the quarry yet (the multiple days between returning to the quarry were from a combination of job commitments and rain). It was in the low 40’s and WINDY – the wind cut through all of our layers! However, we had work to do – namely, getting prepared for the heavy machinery to come and collect our massive jacket(s) to hall down the slope and across the muddy flats into the bed of a pickup. We climbed up the slope to assess everything – and were shocked when the mining equipment was already headed their way! They were ready to go and they were more than happy to work on their schedule, since they were allowing the museum access to the quarry, halting work on the slope the fossil was found in, and taking time out of their day to help them with moving the jackets. When the giant equipment got closer to us, Dr. B started laughing – the sheer size of it was incredible – it was actually large enough to make their gigantic jacket look tiny! It took 8 people (more would have been welcome, but there wasn’t space around the jacket for them to fit) to move the ~400 pound jacket into the bucket of the bulldozer – an immense task of its own. We then moved the two smaller (but still too large to carry easily down the slick slope) into the bucket, and then the bulldozer moved down the hill with half the crew to get it into the bed of a pickup truck. This half of the crew then went downtown to deliver the specimens to the museum, while the other half remained at the (very cold) quarry, continuing to work on the associated bone scatters – more vertebrae and the right mandible. Work was going well, but we ended up having to leave the quarry earlier than expected – it turns out, Rich’s MSHA (Mine Safety and Health Administration) certification had expired. This wasn’t a huge deal on most other days, as there were others in the quarry while they were in there that had current MSHA certifications – but the quarry operators were leaving early that day. We hurriedly made top jackets for the two bone clusters we were working on; with Christmas right around the corner, we figured it would be a few weeks before we were able to return (when quarry workers were back in the quarry again.)

The giant front loader that helped us get the jackets out of the quarry and down to the trucks.

This machinery was so large it dwarfed the jackets.

More straps attached to get the jacket into the bucket.

Teamwork makes the dream work!

They weren’t kidding around when they said they had a machine that could help!

Backing down the muddy slope to transport our jackets to the vehicles.

The second half of the crew left the quarry to take the jackets to the museum – they are currently in the collections room!

 

DAY 7 (January 20, 2021) – THE FINAL DAY!

We knew they only had a few hours of work left finalizing this dig – after a (very) long break, we were finally able to return to the quarry and wrap this dig up! The mine operators requested we go in after the mining crew was done actively working for the day, so we showed up at 2, and were in the quarry around 2:30 after paperwork was signed and finished. We immediately set to work – we didn’t have much to do, but needed to finish before the sun set. We continued trenching the smaller block of vertebrae, and by 3:30 work with a reciprocating saw made a quick pedestal of the jacket containing the right mandible, which was then flipped and the plaster jacket completed on the other side. The cluster of vertebrae were also moving quickly – having a large team to all work together and trade off when someone was getting tired (and then hitting their hand with a hammer too many times…) worked beautifully. Some more bone was found in the trench wall, but was also removed in blocks with the reciprocating saw – the final blocks were jacketed, and removed from the quarry – they had finalized and wrapped this excavation up after 7 days of hard (albeit spread out) quarry work!

The last day! Finalizing the leftover bone scatters to jacket and remove from the quarry.

Some of the jackets were finished early, and placed into a game cart to get down to the vehicles – they were too heavy to hand carry.

Our leader, Dr. Boessenecker, taking a well-earned rest from leading our crew in this MASSIVE endeavor.

A bulldozer wasted no time getting into working the quarry we had been working in – we could not have done this without the generosity of Giant Cement Quarry holding off on digging into this slope for us to finish our excavation.

A final view of a sunset as we left Giant.

 

Why this specimen is so important?

We’re a small museum with limited resources, so why go through all this trouble? Many basilosaurid fossils have been found, after all. Letting one be turned into concrete would certainly be a minor tragedy – though more are guaranteed to be discovered. In this case, the identification of this specimen is key: we had a species-level identification within the first few hours of digging. What’s so special about Chrysocetus healeyorum? For starters, it’s not very well known: the holotype specimen – the specimen that the species naming was based on – has a very fragmentary skull and partial mandibles associated with proportionally large teeth, and an assortment of vertebrae and ribs, along with a partial pelvis. Simply put, there’s a lot to gain just from the standpoint of filling in missing pieces.

More critical, however, is the potential evolutionary story told by the original specimen. Chrysocetus was proposed to have only a single set of teeth – either milk or permanent teeth – a key evolutionary step in the evolution of modern whales and dolphins. Baleen whales do not have adult teeth, and all modern toothed whales (Odontocetes) only have a single set. As it turns out, it’s extremely difficult to tell whether the retained teeth in modern dolphins are the adult or milk teeth – and we actually don’t know if they lost their milk teeth, or lost the ability to produce the adult set (their “adult” teeth might actually just be milk teeth).

As a result, Chrysocetus healeyorum has been interpreted as the basilosaurid most closely related to the Neoceti – the group including baleen whales (Mysticeti) and dolphins and other toothed whales (Odontoceti). The early radiation of the Neoceti is typically studied in the context of Oligocene age early dolphins and baleen whales – a key focus here at CCNHM – but this specimen gives us an opportunity to look at this diversification event from the other side, to speak. Our new whale has a more complete lower jaw (and likely skull) than the original specimen, and appears to have much more of the dentition. These teeth are also hollow shells that have not been completely formed yet, perhaps giving us an earlier window into the growth of Chrysocetus. This new skeleton will allow us to test the hypothesis that Chrysocetus had only one set of teeth, and its relationship with the Neoceti.

We could not have managed this ordeal without all of our help from amazing volunteers!

CCNHM is extremely grateful to Giant Cement Quarry for allowing us to conduct fieldwork in their quarry, and for facilitating removal of large plaster jackets with their equipment. We thank Rich Familia for getting us into the quarry and arranging for mining equipment to help out. We also thank Mark Bunce for discovering this whale (and causing everyone a bunch of well-earned backaches), and all of the volunteers who helped along us the way: Ashby Gale, Jordy Wolfe, Shelley Copeland, Schuyler and Josh Basak, Matt Gibson, Jessie Peraginie, Alex Mertz, Everett White, Laurel Black, Scott Harris, Stuart Clayman, and Michael Musick.

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Posted in Fieldwork, fossils, Museum

Friday Fossil Feature – Museum Collections Improvements!

By Sarah Boessenecker (@tetrameryx)

Happy Fossil Friday!

Collections manager Sarah was ecstatic about this (and getting people to do the heavy lifting for her…)

Here’s a different type of Friday Fossil Feature: not a fossil directly, but even better! (in the humble opinion of one museum staff member at least…)

Fossils are wonderful, but where are they kept if not on display?

The Collections Room! insert ‘The Room Where it Happens’ song from Hamilton

2 months ago, CCNHM was the proud recipient of 5 BRAND NEW Lane Cabinets! We also got 51 new drawers to go inside these (and previously existing) cabinets, ready to be filled with fossils. This increased storage space in Collections cabinets by 25%, and drawer space by a whopping 41%! While that may not seem like a lot, every little bit of storage space counts when you work in a museum.

What’s in the box?! A collection manager’s dream present – a band new lane cabinet!

What will they do with all this extra space? Well, fill it with fossils, of course. But, before they start adding more fossils, it’s the perfect opportunity to rearrange everything, and place fossils in stratigraphic order. What does this mean, exactly, and how is it being done?

So so pretty, and just waiting to get filled with fossils!

At the beginning, fossils were not arranged by taxon or stratigraphically; they were placed into cabinets as needed, and as more fossils came in, they were added to those cabinets but not following a formal organization scheme: they were simply added as space allowed. Some cabinets were dedicated to particular groups. Museum staff had been wanting to re-organize the cabinets for 5 years – and finally were able to do so with the new arrivals and added storage space!

These cabinets are HEAVY – requiring multiple people to lift and shift them over. Here, museum curator Dr. Scott Persons and Mace Brown Museum Research Fellow and Adjunct Lecturer Dr. Robert Boessenecker slide a cabinet into its place.

Curator Dr. Scott Persons assessing the next cabinet needing put in its place.

Geology Department professor Dr. Norm Levine also helped with the cabinet installation!

 

Dr. Levine and Dr. Persons removing the plastic wrap from the cabinet, while Dr. Boessenecker admires all of the extra room we will be having for fossils.

Team work makes the Dream work!

Placing fossils in stratigraphic order means having them sorted by age – having fossils from the oldest rock layers first, and working our way up to the Pleistocene (ice age) fossils. In a sense, the collections cabinets are a timeline of evolution; having things sorted by age helps to show trends in evolution, and walking along the cabinets is a journey through time. We have used both methods for the rearrangement of our collections – overall, specimens are placed in stratigraphic order, but in that stratigraphic order, they are then placed in taxonomic order, and grouped by locality. That is, all mysticete (baleen whale) fossils from the Ashley Formation are grouped together, and fossils from one locality are grouped with others from the same locality. Odontocete (toothed) whales were treated the same – those from the same formation grouped, and those within that formation were grouped with other fossils from the same locality.

Putting the final cabinet in its place.

How is this being accomplished? Hard work. Lots of hard work. Not mentally taxing, more physically taxing – first, museum staff went through all of the drawers in cabinets and made note of what time period the fossils within were from, and labeled the drawer with relevant information. Then, a bit of mental work went into it: seeing how many fossils from one time unit we had, and how likely it was for us to get more fossils from that particular time period. Older time periods (the Silurian, for example) were represented by a handful of small specimens, but nothing local (South Carolina doesn’t have any rocks that old!) and as such, were not likely to grow in size. However, most of the time periods represented in South Carolina and our collections are Oligocene in age; the Ashley Formation (Rupelian/early Oligocene) and the Chandler Bridge Formation (Chattian/late Oligocene). Understanding that our fossil collection from these two formations (and with that, time periods) would grow, we knew they would ultimately take up more space. We tallied up how much we had representing each time period, and pulled all of the fossils out of their drawers – that’s where it became physically taxing, as some of these fossils were quite large – they are whales, after all!

Some cabinets had multiple time periods in it as they had less (or smaller) specimens, like the cabinet that has Paleozoic – Eocene aged fossils inside. The cabinets around it have only one time period – the Oligocene, and the 2 different formations within it that are found in the Charleston area.

Then came the drawer shuffling; the drawers can be placed at different heights to allow for different sized fossils to fit inside – we moved the drawers over into the new cabinets, and slowly moved fossils over, leaving some empty drawers to allow for expansion.

Archival foam was laid out and a template cut to drawer size was used to cut out foam inserts. As some of the fossils were too large for specimen boxes, they were placed in the drawer directly – but it’s important that they are not resting on bare metal, and instead on foam cushion.

Stickers! Stickers designate important fossils inside the cabinet and drawer. In our case, a red star means a Holotype (a specimen for which a taxon is named in a publication), a blue star is for a new Genotype (a specimen a new genus is named from) and a green star is for a published specimen. Fossils in our cabinets can have any 1, 2, or 3 of these stars designated to them.

This drawer houses material from Cotylocara – which is a published specimen (green star) and also serves as a holotype (red star) and genotype (blue star). The other drawers in this cabinet are not published yet, or do not represent new holotypes or genotypes.

By doing this, we were able to reassess what we had in collections, and make a game-plan for expansion – for example, if we had a large number of taxa represented in the collections that were not relevant to the research happening at CCNHM, less drawer space was allocated for those taxa as we were would not actively collect or seek them out to add to the collections. Having a strong collections policy is vital for the success of any museum – it allows for a guided expansion, and keeps their focus on their mission – for us, educating the lowcountry public on our local fossils!

All of the cabinets were assigned a number (which is referenced in the database, so a fossil is easy to find when looking for it) and are also labeled with what they contain. This cabinet is a mixture of beach and river finds from the area – often these fossils are found ex situ (not embedded in the rock anymore) so a rock formation is not always clear.

Some cabinets were reserved for large collections within our collection – Rita McDaniel donated her entire fossil collection from the Lee Creek Mine. For large bequests such as this, it was important for all the specimens to stay together.

HUGE THANK YOU to Dr. Scott Persons, Dr. Norm Levine, and Dr. Robert Boessenecker for getting all these cabinets in place for our Collections Manager Sarah to organize and fill with fossils!

How many collections managers can fit in a Lane cabinet? 1, with room to spare.

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Posted in fossils, Museum

A Whale of a Tale

By Sarah Boessenecker (@tetrameryx)

Happy Fossil Friday!

Manaia in all her glory!

After a long and fascinating journey, our cast of Dorudon atrox, affectionately named ‘Manaia’ has finally reached her final resting place in the Addlestone Library, after being hung in the rotunda to watch over students studying. Dorudon is a basilosaurid whale – an early ancestor to mysticete (baleen) and odontocete (toothed) whales and is found in Eocene aged (~56-34 million years old) rocks. With a total length of ~5 meters, Dorudon was one of the smallest basilosaurids, but still a fearsome predator of shallow seas.

Would you like to hear more about Manaia’s travels, and how she came to be here? Read on!

It all starts in San Francisco, where this cast was originally displayed in the flagship Discovery Channel Store. The store was shutting down and needed this whale out – and soon. The store manager reached out to California Academy of Sciences where Dr. Douglas J. Long worked to see if he wanted the skeleton. He did – but it needed to be gone the following day! The skeleton was collected (no easy feat – it’s quite heavy!) and transported to Cal Academy. However, issues immediately arose; the Exhibits Department did not want the skeleton, the Earth Sciences curator did not want it for the Paleontology Collections since it was a cast, and the Mammalogy and Ornithology collections (where Doug was curator) didn’t have room for it either. It sat for months in limbo (and in the way) before Doug came up with the idea to offer it to St. Mary’s College of California where he also lectured in Biology – the dean there was also a vertebrate paleontologist, and thought it would be great to be suspended in the 3 story spiral staircase of the brand new sciences building. Problem solved!

Manaia hanging in the flagship Discovery Channel Store in San Francisco (photo credit http://www.pompeic3.com/)

However, it didn’t quite work out that way. Unforeseen circumstances blocked the way, and funding to install and hang the skeleton went awry; the skeleton was back in limbo (and still in the way).

Doug was put into an uncomfortable position – as he was the one who arranged to get the whale from the Discovery Channel Store, the onus to fix this “problem” was on him. Luckily, Doug had another idea – he had just built a 27’ Tiki Shack in his backyard, and there was ample space in the rafters for just such a thing! He enlisted the help of a couple of friends, they mounted the skeleton finally in the rafters, named her “Manaia” for the Māori creature that served as a messenger between the land of the living and dead, and she stood guard over hundreds of bottles of rum for 15 years.

Protector of the Tiki Bar. (photo credit Douglas J. Long)

Manaia’s horde she watched over. (photo credit Douglas J. Long)

Manaia’s horde of expensive rum… (photo credit Douglas J. Long)

As Robert Frost once wrote, “Nothing gold can stay,” and Manaia was once again about to be in limbo – in early 2019 Doug had taken a new job in Southern California and was faced with the dilemma of what to do with this whale. Fortunately, he and our very own Dr. Robert Boessenecker had a friendship and history together involving study of California fossil bearing localities for over a decade – and Doug reached out to Dr. Boessenecker, knowing he is a “whaleontologist” and thought it might be something he would like to have for the museum!

Excited about this idea, Dr. Boessenecker leapt at the chance to get such a wonderful creature for the museum to display – after all, Dorudon was first discovered and described from South Carolina, so what could be better than our very own mount?

There was a catch though – Doug was moving soon and needed the whale gone sooner (this seems to be a trend) – and in California. Doug wanted to give it to the Mace Brown Museum of Natural History for free – we just needed to cover the cost of shipping. Dr. Boessenecker knew he wanted this for the museum – but how would the cost of shipping be covered?

Mace Brown (namesake of the museum, and the individual whose collection it started as before donating it all to the College of Charleston) also recognized the importance of the specimen and offered to cover the cost of shipping entirely. All Doug had to do was contact a shipping company and talk them into quickly building a crate and support to transport this beast across the country – no easy task!

Manaia arrived in February of 2019 amid much fanfare – Dr. Boessenecker and Collections Manager Sarah Boessenecker were eager for the crate to arrive – they weren’t sure quite what to expect. How would she arrive? Would she be in one piece, or would she have been rattled apart during the cross-country drive?

IT’S A GIANT BOX (collections manager for scale)

Dr. Robinson helping to move Manaia indoors.

With the help of stockroom manager Dr. Phil Robinson, the Boesseneckers were able to move the MASSIVE crate inside to assess how to access the whale inside – it had been nailed together with hundreds of nails and involved hammers and crowbars to get inside. Luckily, the cross-country trek had not damaged Manaia at all – the only damages were from the initial crating back in California by the moving company. The Boesseneckers were ecstatic – until they had to think about how they were going to get Manaia from the stock room to the 2nd floor and into the collections room.

Dr. Robinson lent a hand!

A giant present!

Sarah Boessenecker beginning the un-crating.

Assessing how to unbox the rest of Manaia.

Dr. Boessenecker pondering the move upstairs.

Mania unboxed.

Dr. Boessenecker, judging how best to transport Manaia upstairs.

The Boesseneckers feeling uncertain on how best to finish moving the beast.

They wrangled up a handful of students to help – it was a tricky endeavor, as the skull and front end of Manaia was close to 250 lbs and there were no easy places to grab ahold of without risking breakage. They managed after an hour or so of assessing the best way – she couldn’t go up the stairs, but would she fit in the elevator? (She did, with just inches to spare) However, the wooden support she rested on would not – this meant the students and the Boesseneckers had to hold her without breaking her the ride up the elevator and walk her down the hall, while others grabbed the support and followed close behind so she had a place to rest without breaking (she couldn’t rest on her back or side directly without ribs and vertebral processes snapping).

Manaia, after safely being transported into the Collections Room, resting on her wooden supports.

Once safely in Collections, the Boesseneckers were able to evaluate the overall condition of Manaia, and work out a game-plan on which parts were broken, which were missing after all of the moves she went through, and which parts simply needed paint touch-ups. They began the long process of photogrammetry – taking a series of photographs to capture the likeness of an object from all angles that can then be used to build a 3D model that can be scaled to various sizes, or mirrored to replace parts that were missing entirely. After 3D printing the missing pieces, they were able to paint the plastic 3D prints to match the colors of the cast, and attach them to the skeleton. A few more paint touch-ups and puttying on the skeleton to get it into shape for mounting in the library, she needed a sponge bath – years of hanging in a tiki bar left her with quite the buildup of grime! With the help of museum docents and volunteers, she was in pristine condition, and ready for transport once again – TTS Studios was contracted to install Manaia in the Addlestone Library. They picked her up from the Collections room and gave her a quick ride to their studios to assess the cast for hanging purposes, make certain the armature connecting the parts was solid, and test the hang in their workshop. After they were satisfied and ready to go, Manaia was once again on the move – to her final home! The installation was surprisingly quick and painless, thanks to their expertise – and she looks wonderful, swimming through the Addlestone Library rotunda.

Dr. Boessenecker, Whale Mechanic?

Sarah Boessenecker painting 3D prints for Manaia.

Student Addie Miller giving Manaia a much needed bath.

TTS was brilliant in the hanging and installation of Manaia.

Glamor shots of Manaia.

Dr. Boessenecker making some final paint tough-ups.

Dr. Boessenecker and student Addie Millie making final touch-ups.

Student Addie Miller, Collections Manager Sarah Boessenecker and Curator Dr. Scott Persons giving Manaia a final sponge bath.

Cleaning all the nooks and crannies.

Dr. Boessenecker and Dr. Persons monitoring the hanging.

The team had earned some donuts after it was all finished – curator’s treat!

After a long journey (both time, work, and miles) Manaia had made it, and it is all thanks to Dr. Doug Long for donating the specimen, Dr. Boessenecker for helping to secure the donation, Mace Brown for funding her transit, CCNHM Curator Dr. Scott Persons for arranging the installation, TTS Studios for the installation, Dr. Tim Callahan for guidance and help with connecting us with the Libraries, our student volunteers/museum docents Addie Miller and Shelley Copeland for aid in cleaning and painting, and especially  the CofC Libraries generosity, space, and funding for installation.
Go and visit her – free, and open to the public!

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Friday Fossil Feature – What Makes a Fossil Hunter Happy? Finding His Porpoise!

By Robert Boessenecker (@CoastalPaleo) and Sarah Boessenecker (tetrameryx)

Happy Fossil Friday!

Porpoises belong to the modern family Phocoenidae, and are one of the less diverse ‘families’ of modern echolocating whales (Odontoceti), with six species in three genera. They are all typically quite small, and have a near worldwide distribution; the harbor porpoise itself (Phocoena phocoena) lives along most northern hemisphere coastlines in temperate latitudes; other porpoises have a more limited distribution, with some living in small embayments, like the critically endangered Vaquita (Phocoena sinus). Modern phocoenids have short snouts, and big lips for suction feeding; their teeth are quite distinctive and are spatulate rather than conical like most other odontocetes.

A modern harbor porpoise, Phocoena phocoena (from Scholastic.com)

Porpoises have a diverse fossil record, and extend back to the late Miocene of California and Japan; fossils indicate they were more diverse and disparate than they are today (disparity = ecological diversity). Phocoenids seem to be the dominant small odontocetes from upper Miocene and Pliocene deposits of California and Japan, with few examples of modern oceanic dolphins (Delphinidae), suggesting some significant and rapid faunal change between the Pliocene and modern day. Today, delphinids are the most diverse and numerically abundant small odontocetes in almost every ocean basin. In the latest Miocene and Pliocene of the North Pacific, however, there were delphinid-like porpoises with long snouts and approaching the size of bottlenose dolphins, as well as smaller harbor porpoise like species; and, of course, bizarre species like the ‘skimmer porpoise’ Semirostrum ceruttii (Racicot et al., 2014). Certain species may have been present in both California and Japan, in a specialized province with little communication with the North Atlantic or south Pacific (Boessenecker, 2013).

Life restoration of the skimmer porpoise Semirostrum ceruttii (by R.W. Boessenecker)

The North Atlantic Pliocene odontocete record is mostly known from fossil assemblages from North Carolina, Belgium, and the Netherlands. These fossil assemblages are dominated by delphinids including many modern genera. Phocoenids, however, are rare, and known only from two specimens from the Pliocene of Belgium apparently belonging to different genera – Septemtriocetus bosselaersi, and Brabocetus gigaseorum (both named for the discoverers of each skull). These fossils post-date the opening of the Bering strait, and likely represent an early dispersal through the Arctic from the North Pacific, along with the extinct walrus Ontocetus emmonsi. However, no fossils of phocoenids have ever been discovered in the more richly sampled Pliocene deposits of the Atlantic coastal plain of North America. This includes the famous Yorktown Formation at the Lee Creek Mine in North Carolina, arguably the Pliocene marine fossil assemblage we know the most about worldwide; no porpoises at all (Whitmore and Kaltenbach, 2008). The Yorktown assemblage is dominated by ‘modernized’ cetaceans that inhabit the North Atlantic, whereas most of the cetaceans from Pliocene deposits in the North Pacific belong to extinct genera, families, or gener/families no longer inhabiting the North Pacific  – again, indicating faunal endemism different from the modern fauna.

Skull of the early Pliocene phocoenid Brabocetus from Belgium (from Colpaert et al., 2016).

Recently, friend of the museum and donor Ashby Gale and his fossil tour clients (Ashby runs a local business taking visitors to publicly accessible fossil localities) discovered the first fossil phocoenid from the Western North Atlantic (to my knowledge). It is an isolated earbone collected from Folly Beach, South Carolina; the first was discovered last fall, and a second specimen was just found last week and generously donated by his client Don Pendergast. Ashby informs his clients of the scientific significance of the specimens they find and as a result many donations have been made to the museum (thanks!). Bedrock exposures do not exist anywhere on the barrier island; in fact, the fossil-bearing deposit is located offshore, and most of the fossils were accidentally dumped on the beach as part of a beach renourishment project where seafloor sand was added to the beach as a means to curb barrier island erosion; a slurry of seawater and sand is pumped from the shelf to the beach by means of a large pipe. This was last done in 2014, and it introduced a ton of fossils and large sandy limestone blocks onto the beach; Folly Beach residents quickly became vocal about the rough debris. Fossil collectors rejoiced, however, as fossils may now be found quite regularly.

Left periotic of a phocoenid porpoise, cf. Phocoena, from the ?Goose Creek Limestone, Folly Beach, South Carolina.

So how old is this earbone? In particular, vertebrate fossils seem to arise from four sources. Shark teeth appear to represent Oligocene, early Miocene, and Pliocene assemblages, with certain extinct species  reflecting each time period. These sources are probably the Ashley Formation (early Oligocene) which underlies most of the Charleston Embayment and produces rare Oligocene cetaceans and teeth of the megatooth shark chronospecies Carcharocles angustidens; the second is the lower Miocene Marks Head Formation, which produces rare sharks and marine mammals indicative of the late early Miocene (rugose teeth of archaic dolphins, earbones of early baleen whales like Parietobalaena, etc., the chronospecies Carcharocles chubutensis). The last, and most significant source, is the Pliocene Goose Creek Limestone; this unit produces most teeth including great white sharks (Carcharodon carcharias), the famous Carcharocles megalodon, and many marine mammals. Most dolphin earbones from Folly Beach either directly match species from the mostly contemporaneous Yorktown Formation. A younger unit is present, but is terrestrial and it yields abundant Pleistocene terrestrial vertebrates (turtles, horse, armadillos, etc.); it is an unlikely source for the periotics discovered on Folly Beach.

Ashby Gale’s discoveries are currently being worked on by CCNHM paleontologists, and one specimen is currently on loan to our colleague Dr. Rachel Racicot for CT scanning at Vanderbilt University. We hope to have these interesting (albeit fragmentary) records of porpoises published in the future!

 

References

  1. W. Boessenecker. 2013. A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans. Geodiversitas 35(4):815-939

Link: http://www.bioone.org/doi/abs/10.5252/g2013n4a5

  1. Colpaert, M. Bosselaers, and O. Lambert. 2015. Out of the Pacific: A second fossil porpoise from the Pliocene of the North Sea Basin. Acata Paleontologica Polonica 60(1):1-10

Link: https://www.app.pan.pl/article/item/app001152014.html

  1. A. Racicot, T. A. Deméré, B. L. Beatty and R. W. Boessenecker. 2014. Unique feeding morphology in a new prognathous extinct porpoise from the Pliocene of California. Current Biology 24:7:774-779

Link: http://www.cell.com/current-biology/fulltext/S0960-9822(14)00199-7

  1. C. Whitmore and J. A. Kaltenbach. 2008. Neogene Cetacea of the Lee Creek Phosphate Mine, North Carolina. Virginia Museum of Natural History Special Publication 14:181-269
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Friday Fossil Feature – 4 Specimens are Dolphinately Better Than 1

By Robert Boessenecker (@CoastalPaleo) and Sarah Boessenecker (@tetrameryx)

Happy Fossil Friday!

Earlier this week a new paper from CCNHM paleontologist Robert Boessenecker was published in the open access journal PLoS One, reporting new anatomical details for the extinct dolphin Albertocetus meffordorum. The paper was a collaboration between College of Charleston and the New York Institute of Technology, with scientific contributions from NYIT student Erum Ahmed and paleontologist Jonathan Geisler. The paper is open access, meaning that it can be read for free and downloaded directly from the PLoS One web page, here.

The newly published material of Albertocetus meffordorum (shown in red) and map of where it was discovered.

Background: What is Albertocetus?

Albertocetus meffordorum was named quite recently (Uhen, 2008) and based on a single skull from the Belgrade Formation at Onslow Beach in North Carolina. The Belgrade Formation is late Oligocene in age, approximately 25-27 million years old (Ma). Albertocetus was the first xenorophid dolphin reported from outside the Charleston area in South Carolina. The xenorophids are a formerly poorly-known group of very early-diverging echolocating whales (Odontoceti). Originally reported in the 1930s by a partial skull, the xenorophids are now known to be a somewhat diverse group of dolphins including large fish-eating dolphins like Xenorophus sloanii, the earliest dolphins for which we have abundant evidence of echolocation – the somewhat smaller Cotylocara macei and Echovenator sandersi, and the tiniest cetacean to ever evolve, the ~1 meter long dwarf toothless short-snouted dolphin Inermorostrum xenops. Most xenorophids have a long, gharial-like snout with double-rooted teeth and pits in the snout and jaw for the teeth to interlock. Albertocetus was the first xenorophid to be described with a braincase and earbones – critically expanding the known anatomy of this group. Phylogenetic analyses have consistently placed xenorophids at the very base of the echolocating whales, though several groups were already contemporaries.

Cranium of Albertocetus meffordorum. CCNHM 303 in (A) dorsal view; CCNHM 218 in (B) dorsal view; maxilla fragment of CCNHM 303 in (C) lateral, (D) ventral, and (E) medial view. Cross-hatching denotes damaged or missing bone.

 

What’s new about Albertocetus?

The new fossils described by Boessenecker et al. (2017) include a number of specimens from South Carolina and North Carolina. Two skulls from the lower Oligocene Ashley Formation (~28-30 Ma) near Charleston, South Carolina, preserve much of the same anatomy as the original ‘type specimen’ (a skull at the Smithsonian) but one of these is associated with a ~50% complete vertebral column and several ribs. This skeleton, collected by College of Charleston students in the 1990s, also has part of a mandible and an earbone that was removed from the skull (in the type specimen, the earbone is still embedded in the skull). The second skull was CT scanned and a digital endocast was studied – in other words, the internal surface of the braincase was reconstructed into a 3D model to examine the anatomy of the brain.

The skeleton, collected by CofC students in the 90’s is now on display in our amateur display case. Photo by R. Boesseneker

The vertebral column includes a number of tail vertebrae, which are wider than would be expected for an odontocete. In modern cetaceans – both baleen whales and dolphins – these vertebrae are somewhat narrower than tall, corresponding to the narrow tail stock (caudal peduncle) seen in iconic photographs of whale tail flukes displayed whilst diving. This suggests that a narrow tail stock evolved independently within later odontocetes and baleen whales.

CT scans showing the brain endocast.

The brain endocast is interesting, as it is anatomically intermediate between the ancestors of modern whales, the Basilosauridae, and modern dolphins. The brain is still somewhat elongate and conical, and has enlarged temporal lobes and relatively small frontal and parietal lobes. In contrast, modern dolphins have greatly enlarged frontal and parietal lobes and proportionally smaller temporal lobes. This brain anatomy suggests that the large brains of the xenorophids evolved early, and perhaps in parallel with modern dolphins – becoming enlarged via a different pathway and using different parts of the brain for cognition.

Because animals – particularly extinct ones – cannot be given IQ tests, the encephalization quotient (EQ) is used as a rough approximation of animal intelligence. It’s essentially a ratio of brain mass to body mass. In this study, the brain volume of Albertocetus was carefully calculated and body mass estimated based off of skull size using equations developed for other cetaceans. Because a large mass of venous tissue is present along the sides and bottom of the brain of cetaceans, a correcting factor was also used to estimate how much volume was actually brain matter versus venous tissue – neither fossilizes and both soft tissues occupy the same space in the skull. Even still, Albertocetus was found to have the highest EQ for any early Oligocene cetacean – surpassed in the late Oligocene by a new, undescribed species of its’ bigger cousin Xenorophus, and by more modernized dolphins in the Miocene and Pliocene. This highlights a rapid increase in brain size across the Eocene-Oligocene boundary – archaeocetes ancestors were not exactly packing supercomputers upstairs.

What caused this rapid increase in brain size? Some flawed studies have suggested that global cooling at this time caused odontocete brains to increase in size as brains produce heat (thermogenesis) and it helped with odontocete body temperature regulation in cooling climates (Manger, 2006). However, there are numerous problems with this study, which has been largely discredited by a large team of experts on dolphin cognition and evolution (Marino et al., 2008). For example – why didn’t baleen whales show a similar increase in brain size across the boundary? Rather than using brains for thermogenesis, the earliest odontocetes were echolocators like Echovenator sandersi (Churchill et al., 2016). Large brains are necessary for complex cognition, and echolocation takes a lot of brain power. Albertocetus was another xenorophid with the same facial and basicranial features indicative of echolocation. Boessenecker et al. (2017) reiterate the conclusions of earlier work that brain size exploded as echolocation evolved – a ‘key innovation’ in the evolution of the odontocetes.

Final message – amateur collections and sample sizes in paleontology

The study of fossil whales and dolphins is often plagued by overemphasis on single specimens: rather than describing a suite of fossils when reporting a new species, only a single fossil is often reported, even if others are known in museum collections. This new study reported multiple new specimens including a skeleton, a skull, and isolated earbones – drastically expanding the known anatomy of Albertocetus as well as providing new information on individual and growth related variation in early odontocetes. Most of these specimens were all collected by amateur collectors, and we would know none of this if paleontologists had not worked with amateur fossil collectors. This new scientific study highlights the importance of embracing larger sample sizes and, most critically, working with amateur fossil collectors to study fossils.

Dr. Boessenecker did an interview with PLOS that you can read here.

 

Further Reading:

  1. D. Uhen. 2008. A new Xenorophus-like odontocete cetacean form the Oligocene of North Carolina and a discussion of the basal odontocete radiation. Journal of Systematic Palaeontology 6(4):433-452 [Article Link]
  1. Churchill, M. Martinez-Cáceres, C. Muizon, J. Mnieckowski, and J. H. Geisler. 2016. The Origin of High-Frequency Hearing in Whales. Current Biology 26:1-6 [Article Link]
  1. Boessenecker RW, Ahmed E, Geisler JH (2017) New records of the dolphin Albertocetus meffordorum (Odontoceti: Xenorophidae) from the lower Oligocene of South Carolina: Encephalization, sensory anatomy, postcranial morphology, and ontogeny of early odontocetes. PLOS ONE 12(11): e0186476. https://doi.org/10.1371/journal.pone.0186476

  2. Manger, P. R. (2006), An examination of cetacean brain structure with a novel hypothesis correlating thermogenesis to the evolution of a big brain. Biological Reviews, 81: 293–338. doi:10.1017/S1464793106007019 [Article Link]

  3. Marino, L., Butti, C., Connor, R. C., Fordyce, R. E., Herman, L. M., Hof, P. R., Lefebvre, L., Lusseau, D., McCowan, B., Nimchinsky, E. A., Pack, A. A., Reidenberg, J. S., Reiss, D., Rendell, L., Uhen, M. D., Van der Gucht, E. and Whitehead, H. (2008), A claim in search of evidence: reply to Manger’s thermogenesis hypothesis of cetacean brain structure. Biological Reviews, 83: 417–440. doi:10.1111/j.1469-185X.2008.00049.x [Article Link]

 

 

 

 

 

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Friday Fossil Feature – Sinking Your Teeth into Coronodon

By Robert Boessenecker (@CoastalPaleo)

Happy Fossil Friday!

Life restoration of Coronodon havensteini. Illustration by Alberto Collareta.

Last week saw the publication of a new paper naming our spectacularly preserved toothed baleen whale Coronodon havensteini. The article was published in Current Biology by Jonathan Geisler and Brian Beatty from NYIT, CCNHM donor and namesake Mace Brown, and of course one of our own paleontologists, Robert Boessenecker. The paper has been in the works for years and we are elated, if not relieved, that it is finally published. This blog post will consider some of the highlights of the paper, but first – a little back story is needed.

CCNHM paleontologist Dr. Robert Boessenecker explaining dental filtration in Coronodon at the Mace Brown Museum of Natural History. Photo by Post and Courier.

Modern baleen whales (Mysticeti) are filter feeders, and do not have adult teeth. They do, however, form teeth as embryos which are then quickly resorbed – this in itself is not surprising as having teeth is the primitive condition for mammals. Instead, as adults, baleen whales possess racks of baleen that hangs from the upper jaw – a highly specialized type of gingival (gum) soft tissue that is made of keratin and is essentially the same type of tissue that makes up horn, fingernail, hooves, etc. Because it is a soft tissue, it typically does not fossilize (though some rare examples definitely exist), and just like fingernails, grows continuously during life (and length is maintained by the tongue rasping away at the inside). Modern baleen whales feed in three ways: gulping large volumes of water after schools of krill and fish while swimming at high speed (humpback/blue whales – rorquals), sucking up sediment filled with tiny burrowing crustaceans (gray whales), and cruising slowly though “clouds” of tiny copepods with the mouth open (right/bowhead whales). Given that modern baleen whales lack adult teeth, and all species in the other group of cetaceans – the echolocating whales, or Odontoceti – possess teeth (given their more common, yet evolutionarily misleading name, the “toothed whales”) have teeth – we should expect a baleen whale ancestor with teeth.

 

Aetiocetus weltoni with teeth and baleen as proposed by Deméré et al. (2008), and a blue whale filter feeding. Artwork by Carl Buell.

A few confusing fossils were reported in the late 1960s from the Pacific Northwest, originally interpreted as archaeocetes given the relatively primitive shape of the skull and, in one case, retention of teeth. One of these was collected, prepared, and published by legendary fossil collector Douglas Emlong – and named Aetiocetus cotylalveus. It was later recognized as an baleen whale, and in the 1990s, a number of additional fossils revealed that there was an entire diverse family of aetiocetids in the North Pacific, now known from Japan, British Columbia, Washington, Oregon, California, and Baja California. Other advances in the last fifteen years included the discovery of additional aetiocetids, the discovery of the bizarre toothed mysticete Janjucetus from Australia, and the redescription of another former archaeocete, Mammalodon (closely related to Janjucetus). A critical scientific advance was the detection of palatal foramina in the toothed mysticete Aetiocetus weltoni (Deméré et al., 2008) – these are holes that transmit blood vessels to “feed” baleen, and are enlarged in all modern baleen whales and all extinct baleen whales that lack teeth, and are thus a bony correlate indicating the presence of baleen. This landmark paper proposed a “stepwise” transition from teeth to baleen in the Mysticeti: a tooth-only stage (e.g. Janjucetus), a stage including teeth and baleen at the same time (Aetiocetus weltoni), followed by loss of the teeth (modern baleen whales). Some eomysticetid whales – higher up the tree than the aetiocetids, and formerly considered to be toothless – had baleen along most of the palate, with a few vestigial “buck-teeth” in the front of the jaws, revealing a fourth stage between aetiocetids and modern mysticetes (Boessenecker and Fordyce (2015).

 

The palate of Aetiocetus showing palatal foramina and modern baleen whales. From Ekdale et al. (2015).

This study has drawn substantial criticism, with certain papers pointing out that the foramina are of uncertain origin, or perhaps too small to infer the presence of baleen. A recent study (Marx et al., 2016) showed a unique pattern of tooth wear on an aetiocetid lovingly nicknamed “Alfred” where the base of the crowns were in pristine condition but the tips of the teeth were worn and scratched – they proposed that the pristine crown was covered in enlarged gums (gums do not typically cover tooth enamel in most healthy mammals). These researchers hypothesized that aetiocetids simply had enlarged gums rather than baleen – and palatal foramina would supply blood to the thickened gums instead, as an intermediate condition between “teeth only” and “baleen only”. Another recent hypothesis is that because modern suction feeding odontocetes have reduced teeth, a hypothetical toothless and baleen-less intermediate may have been possible (Peredo et al., 2017). A very recent paper reported a very early baleen whale (Mystacodon selenensis) with teeth and possible suction feeding habits (Lambert et al., 2017).

 

Revised model of baleen evolution, from Marx et al. (2016).

Coronodon havensteini sheds new light on this debate. The holotype specimen (a holotype is the specimen which a new species is based on) is CCNHM-108, and is a large (~1 meter long) skull with mandibles, many of the teeth, earbones, cervical and thoracic vertebrae, and a bunch of ribs. Other specimens that may belong to this species are curated at Charleston Museum and have been known about since the 1980s but never formally published. CCNHM-108 is the most complete of the infamous “Charleston toothed mysticetes”, and was collected by licensed diver Mark Havenstein from the Ashley Formation in the Wando River in the early 2000s – the species name is in honor of Mark’s discovery. The genus name refers to the beautiful crown-shaped cheek teeth. The specimen was donated to CCNHM shortly after its founding, and was placed on display in the whale room in 2014.

The holotype skull (CCNHM 108) of Coronodon havensteini.

The skull and dentition bear a number of striking resemblances to basilosaurid whales – the common ancestors of the odontocetes and mysticetes, and Coronodon would have thus greatly resembled a basilosaurid in many respects. Basilosaurids have an external nose far out on the rostrum and a series of denticulate shearing teeth, the largest being in the third and fourth premolars – the molars are smaller, with wear patterns indicative of sharing and in some perhaps a degree of crushing as well. Overall having bite force emphasized on the posterior premolars is reminiscent of mammalian carnivores like dogs. The rostrum, like most mammals, is tightly sutured together. Coronodon differs in several ways from the basilosaurid condition: 1) the rostrum is wider and somewhat flattened, a bit like modern baleen whales; 2) the blowhole is positioned further back, just in front of the eye sockets; 3) the bones of the snout are only lightly connected, permitting some flexibility of the rostrum, correlated with filter feeding (but the mechanism is still unknown); 4) the cheek teeth in the lower jaw (p2, p3, p4, m1, m2, m3) are all nearly the same size and shape (upper teeth are more scarcely known) – indicating that the molars have increased in size from basilosaurids; 5) the teeth overlap and have slots between them which water can pass through. Coronodon also exhibits some features of the basicranium that are unique to baleen whales, confirming it as an early transitional toothed baleen whale. Critically, Coronodon lacks palatal foramina – indicating the absence of baleen. It does, however, exhibit widespread enamel and dentine erosion on its teeth, indicating that much of the exposed roots and part of the enamel crown were covered by enlarged gums – as proposed for the aetiocetid “Alfred”, and confirmed here using evidence of periodontal disease, which appeared to be the norm for Coronodon as all specimens share some evidence of dental erosion.

 

 

The cheek teeth of Coronodon.

 

The skull, teeth, and jaw of Coronodon. From Geisler et al. (2017).

These features all indicate that, despite certain features resembling archaeocetes, Coronodon was a baleen whale. The teeth, unlike basilosaurids, interlock in a way that formed a toothy “cage”; interdental slots permitted water to pass through, but not small prey. If the jaws were partially opened, diamond-shaped holes would be present between the upper and lower teeth, meaning that by changing how far open the mouth was, the filter feeding ‘size’ could be adjusted – making for a dynamic filter feeding device. Modern leopard and crabeater seals filter feed for krill and small fish – leopard seals seemingly rip penguin heads off only a few months of the year, and filter feed for most of it. They do not chew with their cheek teeth, and just nip with their canines and incisors – so tooth wear accumulates only on the teeth in the front of the jaw (Hocking et al., 2014). In Coronodon, we see the same pattern: tooth wear on the front teeth, and minimal tooth wear on the denticulate cheek teeth – which is very different from basilosaurids, despite dental similarities. This indicates that, like leopard seals, Coronodon avoided chewing hard prey with its cheek teeth, likely to preserve the shape of the dental filter.

Life restoration of Coronodon showing the mouth – it would have probably looked quite disgusting. Watercolor by Robert Boessenecker.

So what does this all mean? Recent hypotheses have suggested that toothed mysticetes were suction feeders and did not filter feed, with true filter feeding occurring within the eomysticetid whales and further up the tree, with enlarged gums acting as a way to make a better oral “seal”, much like the enormous lips of a beluga or pilot whale. Aetiocetids occur farther up the tree than Coronodon – indicating that tooth-based filter feeding began very early in baleen whale evolution, suggesting that aetiocetids may have been too specialized on their own branch to weigh in on how baleen evolved. After all, functionally toothless baleen-bearing eomysticetid whales appear at the same time as the toothed aetiocetids. Filter feeding – whether with baleen or teeth – thus appears to be intimately linked with the earliest baleen whales, and perhaps the mammalodontids and aetiocetids reverted to earlier forms of feeding (e.g. fish eating) and experimented with their own feeding styles (suction feeding).

The skull of Coronodon on display at CCNHM. Come visit soon!

This is only the tip of the iceberg on Coronodon and other Coronodon-like whales; additional specimens of Coronodon exist in our collection here at CCNHM and at Charleston Museum, and there is a second possible genus known from two skulls, one at each museum – currently under study by Geisler, Beatty, and Boessenecker. Problematic teeth of a Coronodon-like whale have been found in the depths of the Lee Creek Mine in North Carolina. Stay posted for more whale news from CCNHM, and come visit and see the Coronodon holotype, on display!

References/Further reading:

  1. W. Boessenecker and R. E. Fordyce. 2015. A new genus and species of eomysticetid (Cetacea: Mysticeti) and a reinterpretation of ‘Mauicetus’ lophocephalus Marples, 1956: Transitional baleen whales from the upper Oligocene of New Zealand. Zoological Journal of the Linnean Society 175:607-660.
  2. A. Deméré and A. Berta. 2008. Skull anatomy of the Oligocene toothed mysticete Aetiocetus weltoni (Mammalia; Cetacea): implications for mysticete evolution and functional anatomy. Zoological Journal of the Linnean Society 154:308-352
  3. A. Deméré, A. Berta, and J. Gatesy. 2008. Morphological and molecular evidence for a stepwise evolutionary transition from teeth to baleen in mysticete whales. Systematic Biology 57:15-37.
  4. M. G. Fitzgerald. 2006. A bizarre new toothed mysticete (Cetacea) from Australia and the early evolution of baleen whales. Proceedings of the Royal Society B 273:2955-2963

E.G. Ekdale, T. A. Deméré and A. Berta. 2015. Vascularization of the gray whale palate (Cetacea, Mysticeti, Eschrichtius robustus): soft tissue evidence for an alveolar source of blood to baleen.

Hocking, D.P., A.R. Evans, and E.M.G. Fitzgerald. 2013. Leopard seals (Hydrurga leptonyx) use suction and filter feeding when hunting small prey underwater. Polar Biology 36:211-222.

  1. H. Geisler, R. W. Boessenecker, M. Brown and B. L. Beatty. 2017. The Origin of Filter Feeding in Whales. Current Biology 27:1-7
  2. Lambert, M. Martínez-Cáeres, G. Bianucci, E. Steurbaut, M. Urbina and C. Muizon. 2017. Earliest Mysticete from the Late Eocene of Peru Sheds New Light on the Origin of Baleen Whales. Current Biology 27:17
  3. G. Marx, D. P. Hocking, T. Park, T. Ziegler, A. R. Evans and E. M. G. Fitzgerald. 2016. Suction feeding preceded filtering in baleen whale evolution. Memoirs of Museum Victoria 75:71-82
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Friday Fossil Feature – SeAVP and the Gray Fossil Site

by Sarah Boessenecker (@tetrameryx) and Robert Boessenecker (@CoastalPaleo)

Happy Fossil Friday!

Huge attendance for this year’s SeAVP!

Last week, museum staff and volunteers traveled to Gray, Tennessee for the 10th annual Southeastern Association of Vertebrate Paleontology. What’s in Gray, Tennessee? Why, the Gray Fossil Site, of course!

The Gray Fossil Site (GFS) is a Miocene age site known for it’s spectacular preservation of fossils dating back 7 to 4.5 million years ago. GFS was discovered in 2000 while trying to expand the highway in the area; upon realizing the magnitude and importance of such a fossil site, the highway was rerouted to go around and construction began on a museum to house and educate about the wonderful finds coming from this prehistoric sinkhole. Lizards, snakes, turtles, and alligators are all commonly found at this site, as well as tapirs, saber-toothed cats, mastodon, and short-faced bear. GFS is also known for the most complete skeleton of the ancient barrel-chested rhinoceros Teleoceras and the most complete skeletons of red panda!

Partnered with East Tennessee State University, GFS was the host of SeAVP this year; 10 years ago they started this small conference as a way to share new research and catch up with old friends, as well as providing a platform for new researchers to present in a smaller setting before moving onto larger conference settings. Professor Robert Boessenecker presented a 20 minute talk on xenorophids (Oligocene odontocetes) and Collections Manager presented a poster on a new record of the walrus Ontocetus emmonsi from South Carolina. Enjoy the following slideshow of pictures from the trip!

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Friday Fossil Feature – 2017 Aurora Fossil Fest!

By Sarah Boessenecker (@tetrameryx) and Robert Boessenecker (@CoastalPaleo)

Happy Fossil Friday!

Over Memorial Day weekend, museum paleontologists Bobby and Sarah Boessenecker traveled to the town of Aurora, North Carolina for the 24th annual Aurora Fossil Festival.  Aurora is tiny – roughly 500 people live in this small town right along the Pamlico River, and each year it grows to 15,000+ people for a weekend for the love of fossils and fossil-nuts alike!

The trip started with a special visit to Belgrade Quarry to hunt for fossils. Belgrade Quarry is an open-pit aggregate mine – aggregate is one of the raw materials (typically limestone) used for concrete and road metal.  The mine is owned by the Martin Marietta Corporation, and while closed to the public for collecting, they graciously allow the North Carolina Fossil Club and their friends in once a quarter for collecting, and for special events such as the Fossil Festival. The mine exposes rocks from several different units: the Eocene Castle Hayne Limestone, the Oligocene Belgrade/River Bend Formations, and the Pliocene Duplin Formation. Marine vertebrate fossils including sharks, rays, bony fish, estuarine crocodiles, sea turtles, dolphins, and whales are abundant within the Belgrade Formation. This is one of the only Oligocene cetacean-bearing fossil localities on the east coast outside the Charleston area; deposits of the same unit at Onslow Beach, NC, yielded the holotype skull of the xenorophid dolphin Albertocetus meffordorum. Friday morning started early, meeting at the Hardee’s of Maysville, NC at 7:30 am for a quick breakfast and discussion of what to expect in the quarry. We were required to have steel toed boots, safety vests, and hard hats as Belgrade Quarry is an active mining operation. We headed out to the quarry at 8:00 am and watched a short video on quarry safety and what to do in case of emergencies. As they were blasting overburden that morning, we stuck around the office until 9:00 am as per safety protocol, and then it was off for a day of fossil hunting!

(R to L) Jeanette Pirlo, Michelle Barboza-Ramirez, Victor Perez, and Bruce McFadden from the Florida Museum of Natural History preparing to enter the quarry. Photo by S. Boessenecker

Collecting from Belgrade Quarry is surface collecting, with stunning views. Photo by S. Boessenecker

If you look closely, you can see the quick and easy way to find your collections manager while fossil hunting. Photo by R. Boessenecker

Looking south towards the conveyor belts. Photo by R. Boessenecker

Not all life found in the quarry was fossil in nature! Photo by S. Boessenecker

Victor Perez screening for shark teeth. Photo by S. Boessenecker

Bobby Boessenecker prospecting. Photo by S. Boessenecker

We didn’t find quite so much as we had two weeks prior – and we think our earlier trip scoured the place fairly clean. We did find a small number of sand tiger shark teeth (Carcharias cuspidata), tiger shark teeth (Galeocerdo casei, Physogaleus contortus), a nurse shark (Ginglymostoma), and many ray teeth (cf. Myliobatis). Bobby may have found a sperm whale tooth – which is surprising given the rather old Oligocene age of the strata, as only one Oligocene sperm whale is known (Ferecetotherium, Oligocene of Kazakhstan). After a busy and filthy day collecting in the quarry, we drove about an hour back to Aurora for showers and wonderful BBQ food. It was a time to relax and catch up with friends and colleagues, as well as setting up our outreach table for Saturday.

We borrowed casts of Georgiacetus vogtlensis and Zygorhiza kochi from our displays, and made riker cases for fossils collected by Robert and Sarah Boessenecker from Folly beach. Photo by S. Boessenecker

Sarah Boessenecker ready to educate visitors! Photo by R. Boessenecker

The Aurora Fossil Museum houses fossils from the famous Lee Creek Mine and though the mine has been closed to the public since 2009, truckloads of material from the mine are regularly bought in and dumped into large ‘spoil piles’ outside of the museum for collectors to pick through.

1 of 2 spoils piles outside the Aurora Fossil Museum. Photo by S. Boessenecker

One truckload was brought in specifically for the fossil fest, and was roped off – until Friday at 6:00 pm. Visitors (and ourselves) simply could not resist the idea of fresh, untouched spoils from Lee Creek Mine – we spent some time in the pile before the keynote address, finding shark and cetacean teeth right off the bat. We picked up a bucket for the museum and will screen through the matrix this summer, and it will greatly supplement the McDaniel Collection here at CCNHM, which was made by Rita McDaniel, principally as surface collection – which tended to focus on larger specimens. This will give us a better snapshot of species represented by smaller teeth (rays, skates, basking sharks, horn sharks, megamouth sharks, etc.).

The spoils pile looked like an anthill, swarming with collectors shortly after the ropes were removed. Photo by R. Boessenecker

Sarah Boessenecker explaining the futility of the shower she’d just taken. Photo by R. Boessenecker

Jeanette Pirlo, Victor Perez, and Michelle Barboza-Ramirez on what we called “Black Friday for paleontologists.” Photo by R. Boessenecker

Donald Morgan from the Calvert County Marine Museum and Sarah Boessenecker digging through the pile. Shortly after this picture was taken, Donald was informed there was a shark tooth stuck to his leg. Photo by R. Boessenecker

Squalodon calvertensis (shark toothed dolphin) molar found by Robert Boessenecker. Photo by R. Boessenecker

Assorted shark teeth found by Sarah Boessenecker. Photo by S. Boessenecker

Carcharocles chubutensis tooth found in matrix by Sarah Boessenecker. Photo by S. Boessenecker

Eventually though, we had to turn away from digging to attend the keynote address given by Bruce McFadden, curator of the Florida Museum of Natural History in Gainesville, Florida. Bruce has spearheaded the Fossil Project, a group created to encourage the relationships between amateur and professional paleontologists. Bruce has an interest in the terrestrial mammals that can be found in the upper layers of the Belgrade Quarry, dating to about the Oligo-Miocene boundary. His talk expressed the importance these fossils have, and encouraged members of the fossil community to donate their finds so that the terrestrial mammal fauna could be studied and compared with better known assemblages from the Great Plains.

Bruce McFadden giving the Keynote Address. Photo by R. Boessenecker

Saturday morning began the festivities for us; we set up our table the night before and were in the Community Center at 9:00 am to man (and woman) our outreach table.  We were lucky to be in a building with air conditioning! Though it wasn’t nearly as warm as the previous year, we appreciated the cool air.  Our day was busy – it went by incredibly fast!  We got to interact with the public, IDing fossils for them and talking about CCNHM, as well as catching up with many of the members of the NCFC, and getting to see their impressive collections.  We were even lucky enough to snag several donations for our museum collections, which will in turn allow us to write a publication on the marine mammal fauna of Belgrade Quarry.

Where all the cool kids were (and yes, that’s Buck Ward with the goofy umbrella hat.) Photo by S. Boessenecker

Promoting our social media accounts to visitors to our table. Photo by S. Boessenecker

We also brought pictures showing our newest display, the Cone Whale, found in Lee Creek! Photo by S. Boessenecker

Digital scanning by the Fossil Project. Photo by S. Boessenecker

More of the Fossil Project table. Photo by S. Boessenecker

Michelle Barboza-Ramirez working at the Fossil Project table. Photo by S. Boessenecker

Julie Niederkorn with her display at the North Carolina Fossil Club table. Photo by R. Boessenecker

Asst. Curator of Paleontology at the VMNH Alex Hastings brought fossils of the dinosaur variety to the festival. Photo by R. Boessenecker

The Virginia Museum of Natural History had a busy day too! Photo by S. Boessenecker

Lee Cone with his impressive shark tooth collection. Photo by R. Boessenecker

Don Muller and Joel Hardin heading up the Special Friends of the Aurora Museum table. Photo by S. Boessenecker

More displays from the North Carolina Fossil Club. Photo by S. Boessenecker

Our table was busy all day – here, Dave Bohaska of the Smithsonian works with Bobby to ID fossils for visitors. Photo by S. Boessenecker

Dave Bohaska and Buck Ward are staples of the AFF, attending every year. Photo by R. Boessenecker

Buck is an invertebrate paleontologist, and had an impressive table showing the evolution of pectens through time. Photo by R. Boessenecker

A eurhinodelphinid (swordfish dolphin) collected by young collector Trevor Clarke. Photo by R. Boessenecker

Trevor with his find – one of the oldest eurhinodelphinids from the Calvert Formation! Photo by R. Boessenecker

Plenty of outreach designed for kids in mind! Photo by S. Boessenecker

More outreach for kids in mind. Photo by S. Boessenecker

Bobby identifying cetacean earbones, with Donald Morgan at his Calvert County Marine Museum in the background. Photo by S. Boessenecker

Donald Morgan with his Calvert County Marine Museum outreach table. Photo by S. Boessenecker

We also made certain to give the original watercolor of the mock-up for displaying the Cone Whale to Lee Cone, who graciously donated it to CCNHM. Thanks again, Lee! Photo by S. Boessenecker

Plenty was going on outside of the Community Center as well; there were vendors selling an assortment of items, and all the fried food the south could offer, not to mention the continuously busy spoils pile and live music. We took a break from our table to get some food and went through the education tent, and our collections manager Sarah was even able to (excitedly) hold a wood duck!

Never a dull moment in the spoils piles! Photo by S. Boessenecker

Sarah got a little excited to hold this little guy! Photo by R. Boessenecker

We ended the day with a walkthrough of the Aurora Fossil Museum, and catching up with Cindy Crane, the director of the museum, and all around wonder-woman who brings this giant festival together each year.  The museum houses an impressive number of shark displays, including modern and fossil (composite and associated) dentitions, numerous marine mammal fossils, and an entire room with a scale model of the Lee Creek Mine, where the layers are accurately depicted in color and thicknesses.  In this room, you can learn a bit about how the mine operates, what layers the fossils are found in, and why fossil remains are so abundant from the Lee Creek Mine.

Dave Bohaska of the Smithsonian and Cindi Crane, director of the AFF catch up after a long and busy day! Photo by R. Boessenecker

Carcharocles megalodon teeth. Photo by R. Boessenecker

Colors accurate and thickness of beds to scale. Photo by S. Boessenecker

Material (including the Cone Whale!) removed from the pit by draglines. Photo by S. Boessenecker

Depicting the fossil-bearing beds in the Lee Creek Mine. Photo by S. Boessenecker

No visit is complete without a picture in the shark jaws! Dave Bohaska, Cindi Crane, Sarah Boessenecker, and Bobby Boessenecker after an exhausting day!

We ended the night with a spectacular fireworks display, with the excitement of returning next year for the 25th annual Fossil Festival, and the 40th birthday of the Aurora Fossil Museum!

To break up the ~5.5 hour drive back to Charleston, we stopped at another fossil locality, Topsail Beach. At topsail beach you can find Oligocene and Eocene Fossils such as shark teeth, whale, dolphin, and sea cow bones and teeth, as well as echinoids (sea urchins and sea biscuits). Collecting at Topsail Beach is similar to collecting here at Folly Beach near Charleston, but with a higher chance of finding precious Oligocene marine mammal fossils. Marine mammals found at Folly tend to be younger (Miocene and Pliocene).

Topsail Beach. Photo by S. Boessenecker

Bobby collecting at Topsail Beach. Photo by S. Boessenecker

Sarah collecting at Topsail Beach. Photo by R. Boessenecker

 

Sarah after finding her first fossil sea biscuit! Photo by R. Boessenecker

 

All in all, it was a hugely successful and fun weekend, and we would like to thank Cindi and the Special Friends of the Aurora Fossil Museum for extending an invite to us, as well as the North Carolina Fossil Club for their continuous generosity in both donations and inclusion in their events. We will see you all next year, if not sooner!

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Friday Fossil Feature – It would be Folly to pass this site up

By Robert Boessenecker (@CoastalPaleo) and Sarah Boessenecker (@tetrameryx)

 

Photo by R. Boessenecker

Folly Beach is a popular destination near us here in Charleston, and thousands of swimmers, sun tanners, and surfers flock to the beach during the summer and relatively warm spring and fall months; the water is a few degrees warmer than Hawaii, and we will on occasion leave work early every couple of weeks to go swimming. Folly started out as a bit of an artist’s village, and is where George Gershwin wrote the opera “Porgy and Bess” about life in Charleston. Folly Beach is a barrier island, separated from Charleston Harbor to the northeast only by the relatively small Morris Island – the location of Battery Wagner. Battery Wagner was a Confederate artillery battery guarding Charleston Harbor, assaulted in 1863 by Union troops including the 54th Massachusetts Volunteer Infantry – one of the first African American units in the Union Army – and depicted in the 1989 film “Glory”. Hurricanes occasionally uncover Civil War era artifacts, and after Hurricane Matthew last fall, beach walkers found an uncovered store of cannon balls – unclear if solid “round shot” or mortar shells filled with black powder – which, regardless, were detonated by a bomb squad.

Tropical Storm Hermine and Hurricane Matthew uncovered quite a bit of older material this last fall, chiefly fossils and limestone blocks dating to the last 30 million years. A variety of fossils can be found on the beach at Folly, and while not as plentiful as at Edisto Beach, Folly is much closer to us. We’ve gone several times recently, and collected many pounds of fossils. One major scientific issue with collecting fossils from Folly is that the source of the specimens is inconclusively known – and any consideration of the stratigraphic (i.e. geologic) source of the fossils is speculative. Fossils occur isolated on the beach, and except in rare cases, vertebrate fossils do not have any adhering rock. No fossiliferous exposures crop out at Folly, and fossils come from two different sources: 1) natural submarine exposures just offshore and within rivers, washed back onto the beach and 2) sediment delivered by beach renourishment. Folly Beach has been eroding away, and within living memory the width of beach and dunes has decreased noticeably, with hurricanes like Hugo (1989) contributing; other factors include the construction of the Charleston harbor jetties, which prevent sediment from Sullivan’s Island being transported south to Morris and Folly. Sediment for renourishment is either dredged or piped up from “borrow” areas – some of which are in river mouths, but most is from about 3 miles offshore. Renourishment in 2015 from the offshore borrow area introduced a large number of limestone nodules, which have been the source of much ire and complaining from Folly residents, but possibly a boon for geologists.

We still don’t have a great idea of what strata are exposed in these areas, and several problems plague stratigraphy in the Charleston embayment: 1) Exposures are rare and many deposits are known only in the subsurface, either from well cores or seismic data; 2) many deposits, according to seismic data, are not laterally extensive and taper out over a few miles – making mapping and correlation a bit of a nightmare. We’ll be using the stratigraphic framework from the geologic map of the area published recently by USGS stratigrapher and paleontologist Rob Weems and others (2014). But before we get there, what fossils can you find?

Photo by R. Boessenecker

Hemipristis serra, the snaggle tooth shark. Photo by R. Boessenecker

Photo by R. Boessenecker

Most visitors come for the shark teeth – and shark teeth can be found. They are perhaps not as common at Folly as at other beaches in the southeastern USA, but I’ve walked away with a dozen after only a couple hours of searching. Common shark teeth include Sand tigers (Odontaspis, Carcharias; Oligocene-Recent), and reef and lemon sharks (Carcharhinus, Negaprion; Eocene-Recent). These all have long stratigraphic ranges, and are notoriously difficult to identify – and could come from any of the Oligocene through Pleistocene strata in the Charleston area. Some of the rarer, larger, and more highly sought after teeth including great white sharks (Carcharodon carcharias, Pliocene-Recent), “bigtooth makos” (Carcharodon hastalis, early-late Miocene), and the megatoothed sharks (Carcharocles megalodon, early middle Miocene to early Pliocene; Carcharocles angustidens, Oligocene), tiger sharks (Galeocerdo, Physogaleus spp.), and snaggletooth sharks (Hemipristis serra, Eocene-Pleistocene) are somewhat better age indicators. Confusingly, all of these occur at Folly Beach – indicating that Oligocene, Miocene, and Pliocene rocks all occur nearby or in the borrow areas. Other sharks including bat rays also occur, and shark/ray vertebrae are also known.

Photo by R. Boessenecker

Fossils of bony fish are common, but typically left behind. Common examples include beaks of the pufferfish Chilomycterus schoepfi (early Miocene to Recent), partial skulls of sea robins (Prionotus sp., Pliocene-Recent), partial skulls of bonitos (Sarda sp.; Eocene-Recent), and osteoderms of a sturgeon (Acipenser sp., Cretaceous to Recent). Fish bones are a bit of a nightmare for paleontologists, since fish have such a high number of bones that typically disarticulate, and comparable parts are rarely found. At Folly, mostly well-preserved, dense elements resistant to destruction are found, meaning that it is relatively easy to find consistently occurring specimens of the same morphology. Unfortunately, we have no record of the more delicately built fishes.

Photo by R. Boessenecker

Reptile fossils are in abundance, unlike equivalent deposits on the west coast. Turtle shell elements are actually quite common, and readily identifiable – for someone who knows about turtles. Shell identification of turtles has always seemed like a black art, but we’ve got quite a few now. Specimens obvious enough for chelonian novices like us include large tortoises (Geochelone, Eocene-Recent, or Hesperotestudo, Miocene-Recent), some sort of a large softshell turtle (Trionychidae indet., Cretaceous-Recent), and pond turtles (Emydidae, Cretaceous-Recent). Our collection includes a large, somewhat flat leg spur of a large tortoise. Sea turtles should be encountered, but it’s unclear if our preliminary searches have uncovered any; a single possible osteoderm of a leatherback sea turtle (Dermochelyidae indet., Eocene-Recent) was collected just a few days ago. Crocodilian remains are comparably rare, and we recently collected a partial osteoderm (scute) of extant Alligator (Eocene-Recent).

Photo by R. Boessenecker

Mammalian bones are the most commonly encountered fossils, and these are almost always left behind. These are fragments of much larger bones – by volume, most I assume are from whales (ribs, mandibles). On occasion highly dense bone fragments likely represent pieces of sea cow (Sirenian) ribs. It is worth picking up each one and checking it over to make sure it’s not an identifiable specimen before chucking it back into the sand.

Photo by R. Boessenecker

Land mammal remains are quite common, and include shards of thin-walled bones with a large marrow cavity (clearly not marine mammals), teeth, and tooth fragments. Horse teeth and fragments thereof are perhaps the most common (Equus sp., Pliocene-Recent), and fragments of teeth and tusks of American mastodon (Mammut americanum, Pliocene-Recent) and woolly mammoths (Mammuthus spp., Pleistoecne-Recent). Tusk fragments of the latter can be identified based on distinctive cross-hatching in cross-section. Teeth of artiodactyls are less common (e.g. Bison, Pleistocene-Recent). Our growing collection also includes remains of edentates – including osteoderms of the giant armadillo Holmesina.

Photo by R. Boessenecker

Occasionally identifiable specimens of whales and dolphins (Cetacea) are found. Marine mammals are more difficult to identify than terrestrial mammals, as teeth are either completely absent (baleen whales) or the teeth are similar between species (toothed whales). Earbones are quite important instead, and two different types of earbones may be found – the periotic and the tympanic bulla. Each look quite strange, but if complete enough, are identifiable to the family, genus, and occasionally species level. One recent find by us includes a partial periotic of baleen whale similar to Parietobalaena from the early-middle Miocene Calvert Formation of Maryland. Another specimen, recently donated by Edisto State Beach Ranger Ashby Gale, is a periotic of a pygmy sperm whale (Kogiidae indet.), an unnamed species that is so far known only from periotics from the Pliocene of North Carolina and Florida. The specimen is not photographed here because it is currently being molded and casted.

Photo by R. Boessenecker

For every genuine vertebrate tooth or bone on the beach, there are about a thousand shells and a handful of black phosphate pebbles. Phosphate is a type of sedimentary “nodule” or concretion formed during periods of low sea level with slowed deposition. Slow deposition also favors the formation of vertebrate rich bonebeds – when phosphate pebbles are present in an area, they are usually concentrated and formed under the same conditions that characterize the concentration of vertebrate fossils into bonebeds. Simply put, if black phosphate pebbles are common, look for bones and teeth! Also keep your eyes peeled for coprolites – fossilized poop. Phosphate pebbles which look like poop are very likely to be just that. Coprolites, bones, and teeth are all phosphatic, and share the same chemistry with phosphate pebbles.

So, we know that there are fossils from the Oligocene, sometime in the early-middle Miocene, the Pliocene, and the Pleistocene from Folly Beach – all mixed together, naturally and by beach renourishment. The geologic map of Charleston published by Rob Weems includes deposits of the lower Oligocene Ashley Formation, the lower Miocene Marks Head Formation, the Pliocene Goose Creek Formation, and the upper Pleistocene Wando Formation. We think that these strata are the likely sources of the fossils from Folly Beach, with the terrestrial reptiles and land mammals all originating from the Pleistocene Wando Formation.

We need your help! The vertebrate fossils of Folly Beach have never been published before in a scientific paper. We are currently seeking donations of vertebrate fossils from Folly Beach to help “fill out” the fossil assemblage in our collection in order to permit scientific study of the locality. If you have found some of the more uncommon fossils – in particular, whale or dolphin earbones or mammal teeth – we encourage you to consider donating the specimens to CCNHM for scientific study and display in our museum!

 

Sources Cited:

Weems, R.E., Lewis, W.C., and Lemon, E.M., Jr., 2014, Surficial geologic map of the Charleston region, Berkeley, Charleston, Colleton, Dorchester, and Georgetown Counties, South Carolina: U.S. Geological Survey Open-File Report 2013–1030, 1 sheet, scale 1:100,000, http://dx.doi.org/10.3133/ofr20131030.

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Friday Fossil Feature – Fintastic surfprises from Lee Cone’s Whale

by Robert Boessenecker (@CoastalPaleo) & Sarah Boessenecker (@tetrameryx)

Happy Fossil Friday!

The more we unpacked, the more excited we got as we learned just how much was donated. Photo by S. Boessenecker

The more we unpacked, the more excited we got as we learned just how much was donated. Photo by S. Boessenecker

Two weeks ago, fossil collector Lee Cone (President of the Special Friends of the Aurora Fossil Museum) donated a spectacular skeleton of a large baleen whale (Mysticeti) from the Lee Creek Mine (read about it here). A skeleton of a mysticete like this is unprecedented as it includes a partial skull, earbones, mandibles, vertebrae, and ribs. However, it also includes a number of other fossils that decidedly do not belong to the whale – including non-cetaceans, parts of at least one or two additional mysticete whales, and at least two pygmy sperm whales (Kogiidae).

Associated fish, sea turtle, and bird remains

Several bones mixed in with the whale record the presence of sea turtles, a sea bird, a sturgeon, and a billfish. Several bones from the edge of a turtle shell – called marginals – record the presence of sea turtles, likely Syllomus aegyptiacus or Caretta, possibly Caretta patriciae, the two most common species from the Lee Creek Mine according to Zug (2001). Another fragmentary bone is identifiable as a parasphenoid bone – a bone located deep in the skull – of a billfish (swordfish and marlins). Sturgeons are represented by a fragment of dermal or skull bone with distinctive pitting – sturgeon are among the more common fish from the mine. The fourth non-cetacean is a proximal humerus fragment from some kind of large alcid bird – possibly Pinguinus alfrednewtoni, an extinct flightless penguin-like auk, and the fossil ‘ancestor’ of the recently extinct (ca. 1840s) Great Auk. More detailed comparisons with razorbills (genus Alca) are necessary.

Noncetaceans from the Cone whale assemblage, including five chelonioid sea turtle shell fragments, a billfish parasphenoid (long element right of center), a sturgeon bone (top right), and a proximal humerus of a large alcid, cf. Pinguinus alfrednewtoni (rightmost)

Noncetaceans from the Cone whale assemblage, including five chelonioid sea turtle shell fragments, a billfish parasphenoid (long element right of center), a sturgeon bone (top right), and a proximal humerus of a large alcid, cf. Pinguinus alfrednewtoni (rightmost). Photo by R. Boessenecker

Pygmy sperm whales

Shortly after Lee brought in the remaining parts of the skeleton, I made a surprising discovery – three additional squamosal bones of a much smaller cetacean. The squamosal is a paired skull bone, so there should only be two – not only does the skull of Lee’s whale have a squamosal, it’s also gigantic. So, there is a minimum of three cetaceans present (based on squamosals) – one large mysticete, and two smaller cetaceans. The smaller squamosals are identifiable as pygmy sperm whales (Kogiidae) based upon their size and shape. Shortly after I began noticing fragments of bone mixed in that were composed of a much finer porosity – individual pores in the bone were tiny and under half a millimeter rather than the much coarser pores in the mysticete. The bones are also much, much lighter, and a distinct difference in density was apparent. After an hour or so I had pulled out dozens and dozens of fragments – indicating that much of the skulls would come together. After about 5 or 6 hours of piecing, it is apparent that not only are there two individual pygmy sperm whales, but at least two genera present.

Kogiid skulls from the Cone whale assemblage, Aprixokogia (left) and cf. Scaphokogia (right) Photo by R. Boessenecker

Kogiid skulls from the Cone whale assemblage, Aprixokogia (left) and cf. Scaphokogia (right) Photo by R. Boessenecker

One of these is similar to Aprixokogia kelloggi already reported from the Yorktown Formation (Whitmore and Kaltenbach, 2008), but also a second smaller taxon that appears closer to Scaphokogia cochlearis from the upper Miocene of Peru – though incomplete, the second skull has a more elongate rostrum than other kogiids. Sperm whales in general are freaky – they have highly asymmetrical skulls, and pygmy sperm whales are even weirder, completely lacking nasal bones. Scaphokogia has a bizarre elongate rostrum that makes other kogiids look well-adjusted and normal odontocetes.

More baleen whales

The first part of the skull I saw was the well-preserved earbones – and I saw this gorgeous little petrosal with attached posterior process and an associated bulla, and remarked “ooh it’s a minke whale!” The earbones are the same taxon which was identified earlier by Whitmore and Kaltenbach (2008) as Balaenoptera sp., cf. B. acutorostrata – something close to the modern minke whale. He then showed me a second petrosal, which I thought was a gray whale and not associated with the skeleton. Later on, I flipped the braincase over and the posterior process was in place still – and much, much larger than the minke whale petrosal. Instead, the gray whale petrosal fit in right in place. This meant that based on earbones, at least two baleen whales were present in Lee’s assemblage!

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Mysticete earbones from the Cone whale. Petrosal of the cone whale (left) and the petrosal and associated bulla of Balaenoptera sp., cf. B. acutorostrata. Photo by R. Boessenecker

The plot thickened yet again when I started looking at vertebrae, because various smaller vertebrae are mixed in to the assemblage. A second atlas and axis are present – and are much smaller, possibly representing the same Balaenoptera individual. Unfortunately, the atlas is much larger than the axis, and they do not fit together – meaning that there is a minimum of three baleen whales based on vertebrae!

Cervical vertebrae of the Cone whale assemblage. Atlas (bottom left) of the Cone whale, and smaller atlas of a second mysticete (just above). Axis (bottom right) of the Cone whale, and an even smaller partial axis of a third mysticete (just above).

Cervical vertebrae of the Cone whale assemblage. Atlas (bottom left) of the Cone whale, and smaller atlas of a second mysticete (just above). Axis (bottom right) of the Cone whale, and an even smaller partial axis of a third mysticete (just above). Photo by R. Boessenecker

Why so many species?

In sum, at least one sea turtle, one bird, two types of fish, two pygmy sperm whales, and three baleen whales are preserved in Lee’s assemblage. How could all this get deposited in the same spot? The Yorktown Formation is characterized by slow sedimentation rates, and is punctuated by several internal bonebeds formed during periods of slow or non-deposition. Slow deposition need not rearrange skeletal assemblages to the point of completely mixing them, but hundreds or thousands or hundreds of thousands of years may have passed with the deposition of only a single meter of sediment – enough to keep the main skeleton’s bones together, but providing ample time to preserve additional specimens vertically near the horizon of the skeleton. This is called a “condensed section” in stratigraphy.

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Boessenecker et al. 2014 in PLOS One

Secondly, all of this went through a dragline and was dumped – so the skeleton shifted somewhat, requiring much piecing together, but the skull and jaws and vertebrae were sort of close to anatomical position. It’s therefore possible that mining operations may have mixed in material as well. Regardless of the process by which these remains were concentrated – geological or anthropogenic – we truly received a gift that has kept on giving. Once again, Thanks Lee!

 

Further Reading

S. L. Olson and P. C. Rasmussen. 2001. Miocene and Pliocene birds from the Lee Creek Mine, North Carolina. Smithsonian Contributions to Paleobiology 90:233-365

N. A. Smith and J. A. Clarke. 2011. An alphataxonomic revision of extinct and extant razorbills (Aves, Alcidae): A combined morphometric and phylogenetic approach. Ornithological Monographs 72(1):1-61

J. Velez-Juarbe, A. R. Wood, and C. Pimiento. 2016. Pygmy sperm whales (Odontoceti, Kogiidae) from the Pliocene of Florida and North Carolina. Journal of Vertebrate Paleontology e1135806

F. C. Whitmore and J. A. Kaltenbach. 2008. Neogene Cetacea of the Lee Creek Phosphate Mine, North Carolina. Virginia Museum of Natural History Special Publication 14:181-269

G. R. Zug. 2001. Turtles of the Lee Creek Mine (Pliocene: North Carolina). Smithsonian Contributions to Paleobiology 90:203-218

 

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