The Antarctic fossil record is one of the least understood in the world, due in large part to its remoteness, ice cover, and extreme conditions. There is much to learn, but Antarctic research is often difficult to do.
“It’s logistically intensive fieldwork,” said Dr. Christian Sidor, Burke Museum curator of vertebrate paleontology and University of Washington (UW) Professor of Biology. He recently led a multi-institution research team to Antarctica for an 11-week expedition funded by the National Science Foundation, which manages the U.S. Antarctic Program.
Christian is very familiar with the logistics involved; this was his fourth research trip to Antarctica in the past 15 years to better understand how life recovered after the Permo-Triassic mass extinction, which happened about 252 million years ago and ushered in the era of dinosaurs.
Megan (Meg) Whitney, a graduate student in the UW Department of Biology, joined Christian for her first trip to Antarctica. Meg’s interest is in anatomy, but she didn’t want to be a medical doctor. “I wasn’t a dinosaur kid—I fell into [paleontology].” Meg is studying the anatomy of fossil bones and teeth at a microscopic scale to understand how animals were affected by extreme seasonality at polar latitudes as part of her PhD.
“We’re working on the mountainsides—the tips of mountain sticking through the glacier,” said Christian. “We use our knowledge of the geology and sedimentology to understand where fossils are likely to be found.”
“When we find a fossil, hopefully we’re finding the beginning of a skeleton and can trace that to the hillside and excavate a big block, including the fossil but also some of the rock surrounding it so it’s protected,” he said.
The Shackleton Glacier area was previously explored by paleontologists only three other times, in 1970–71, 1977–78 and 1995–96. “I was worried that it might have been picked over [by the previous teams],” said Christian. Thankfully that wasn’t the case.
The team found fossil bones, trace fossils including tracks and burrows, and plant impressions—all indications of what life was like about 250 million years ago.
The skeletal material includes small, salamander-like amphibians (temnospondyls), early reptiles such as Prolacerta and Procolophon, in addition to mammal relatives like Lystrosaurus and Thrinaxodon. They also found several other species that will need additional research to determine what they were.
Not much is known about Antarctic amphibians, but Christian believes that will change after this expedition. “In the past, we’ve known which families of amphibians have been there but not which species,” he said. “Because we have so many [amphibian fossils] and they’re so well-preserved, we’ll be able to tackle that question and know what species of amphibians were in Antarctica after the mass extinction.”
In addition, they collected the first identifiable vertebrate fossils from the middle of the Fremouw Formation, which will help narrow down the age of those rocks. Fossils were previously found in the lower and upper parts of the Fremouw Formation, but not in the middle.
Read the full story on the Burke Museum blog.