By Sarah Boessenecker (@tetrameryx)
Happy Fossil Friday!
It’s Darwin Week here at the College of Charleston, so it’s only appropriate that today’s Friday Fossil Feature showcases a fossil near and dear to Charles Darwin’s heart. While traveling on the HMS Beagle, Darwin visited South America and while in Patagonia discovered the fossil remains of great prehistoric animals – these animals were no longer around, though similar taxa were still alive, and this indicated a recent extinction had taken place.
Darwin collected the fossils and carefully packaged them for the return to England, where they were received with great interest.
What were some of these fossils? Why, similar fossils to those still found in the Southern US!
Glossotherium, whose name literally means “tongue beast” was a large ground sloth -over 4 meters from snout to tail, and weighed in at likely close to 1 ton. While mostly quadrupedal, it is thought they could assume a bipedal stance on occasion.
Unlike sloths today that are arboreal (tree-dwelling), Glossotherium likely burrowed with their powerful forelimbs; burrows discovered in the late 1920’s have claw marks matching up with those of Glossotherium and the large ear ossicles are similar to those of today’s elephants, indicating they heard low-frequency sounds better than higher frequency sounds; other fossorial (burrowing) have similar features for hearing today.
Darwin did many other things while traveling on the HMS Beagle; stay tuned for an upcoming series of posts all about Charles Darwin!
Browne, E. Janet (1995). Charles Darwin: vol. 1 Voyaging. London: Jonathan Cape. ISBN 1-84413-314-1.
McDonald, H. Gregory, Larry D. Agenbroad, and Carol Manganaro Haden. “Late Pleistocene Mylodont Sloth Paramylodon Harlani (mammalia: Xenarthra) from Arizona”. The Southwestern Naturalist 49.2 (2004): 229–238 [Full Article]
Estimation of hearing capabilities of Pleistocene ground sloths (Mammalia, Xenarthra) from middle-ear anatomy. R. Ernesto Blanco , Andrés Rinderknecht. Journal of Vertebrate Paleontology. Vol. 28, Iss. 1, 2008 [Full Article]