Surviving on the Colder Side of Life

 

Dr. Jill Mikucki (UT-Knoxville) standing on the snout of the Taylor Glacier at Blood Falls (photo courtesy of Jill Mikucki)

Dr. Jill Mikucki (UT-Knoxville) standing on the snout of the Taylor Glacier at Blood Falls (photo courtesy of Jill Mikucki)

In a recent issue of the journal Science, a team of scientists, including College of Charleston biogeochemist Dr. Peter Lee, described a novel ecosystem in which a microbial community had managed to survive for over a million years in the absence of sunlight and oxygen.  The authors believe that as sea levels decreased and glaciers began to advance across Antarctica pockets of seawater became trapped in the McMurdo Dry Valleys and were sealed off from the atmosphere and sunlight by the advancing glaciers.  Unlike most subglacial lakes in Antarctica that are totally inaccessible without drilling equipment, this subglacial lake periodically discharges through the Taylor Glacier at a location known as Blood Falls.  Using a combination of classical “wet chemistry” methods, modern molecular and genetic techniques, stable isotope analyses and thermodynamic modeling, the team of scientists examined this discharge and found that the surviving microorganisms had adapted to use sulfate andiron compounds as their source of energy but in an unusual way.  Normally when microbes use sulfate for energy, they produce hydrogen sulfide (the compound that causes the characteristic smell of salt marshes) as the end product.  But in this case, they stopped short of producing hydrogen sulfide and instead used the sulfate as a “catalyst” to derive their energy from iron minerals mobilized from the glacier’s bedrock.  These findings provide insight into how life may have survived periods of Neoproterozoic glaciations (“Snowball Earth” events) when some scientists believe that the Earth was entombed in ice.  The authors also suggest that similar ecosystems may provide a “refuge” for life in other inhospitable environments, such as Mars and the Jovian moon Europa.   Articles can be viewed below:

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Dr. Strand Published

Karen K. Martien, Dave Gregovich, Mark V. Bravington,  André E. Punt,  Allan E. Strand, David A. Tallmon, and Barbara L. Taylor recently published an article titled “TOSSM: an R package for assessing performance of genetic analytical methods in a management context” in Molecular Ecology Resources.

Dr. Allan Strand

 

 

 

 

 

 

 

 

Abstract: TOSSM (Testing of Spatial Structure Methods) is a package for testing the performance of genetic analytical methods in a management context. In the tossm package, any method developed to detect population genetic structure can be combined with a mechanism for creating management units (MUs) based on the genetic analysis. The resulting Boundary-Setting Algorithm (BSA) dictates harvest boundaries with a genetic basis. These BSAs can be evaluated with respect to how well the MUs they define meet management objectives.

29th Annual Sea Turtle Symposium

Professor and Associate Dean of Graduate studies Dave Owens has returned from presenting an invited paper at “An International Symposium : Reproduction of Marine Life” at the world famous Okinawa Churaumi Aquarium on the Japanese island of Okinawa.  The Owens paper, with Research Associate Gaëlle Blanvillain as a co-author, was titled “Captive Reproduction of Sea Turtles: An Important Success Story.”  He and three CofC graduate students also attended the 29th Annual International Sea Turtle Symposium, held Feburary 17- 19 in Brisbane, Australia.  Steven O’Connell (GPMB) and Melissa Bimbi (MES) gave oral presentations, and Jesse Alderson (GPMB) presented a poster.

Turtle Nursery

Dave and Gaëlle examining turtle with ultrasound

Grice Scientist Appear on the Today Show

Dr. Lou Burnett and Pacific University collashrimpontreadmillborator Dr. David Scholnick appeared on the NBC Today Show to talk about their work on shrimp physiology using a treadmill that has been made famous on the internet through YouTube. They are interesting in how disease processes can influence performance in shrimp and other crustaceans. They appeared on two segments of the show. Click to view:

Segment  1    Segment 2