By Mary Alice Hartsock, Photos by Ted Daeschler
Academy Vertebrate Paleontologist Ted Daeschler is used to traveling to remote regions of the earth for research. But he’s never traveled quite as far, or seen conditions quite as harsh, as he did last December and January.
His voyage began with a flight from Philadelphia to Los Angeles, and then continued to Christchurch, New Zealand, where he met up with a team of researchers. Together, they boarded a C-130 Hercules cargo plane (interior pictured below) for a seven-hour trip to McMurdo Station, Antarctica.
After their plane landed on Antarctica’s Ross Ice Shelf, Daeschler and team members Neil Shubin (University of Chicago), Adam Maloof (Princeton University), John Long (Flinders University), and Tim Senden (Australian National University) were required to spend a week packing and training for their expedition with professional mountaineer Sune Tamm, who accompanied them in the field. They were headed for the McMurdo Dry Valleys within the Transantarctic Range, located in Southern Victoria Land, Antarctica. There, summer temperatures hover around 15 to 20 degrees Fahrenheit and the land is nearly devoid of life, except for microscopic organisms such as bacteria.
Though 98 percent of Antarctica is ice-covered, the McMurdo Dry Valleys are not covered in ice. According to Daeschler, the Dry Valleys are among the best places to see Middle Devonian strata, about 390 million years old. This area was farther north and part of the Gondwana super-continent during the Devonian, and life found in the rocks is evidence of the warmer, wetter climate of the past. Today, winds whip through the mountain ranges, glaciers and ice falls (above) surround the Devonian rocks, and the frozen land is a prime spot for fossil research.
In the Field
The team spent 12 days at this Mt. Fleming campsite (above) about 100 miles from McMurdo Station. Since water does not run in Antarctica, they cut bricks of snow and heated them in a pot for drinking water. They needed insulated water bottles to keep the water from freezing!
Each day, they worked from about 9 a.m. to 6 p.m., cooked and ate as a group in a designated cook tent, and took time to relax and sleep. With temperatures consistently below 20 degrees Fahrenheit, the researchers’ individual sleep tents offered protection from the steady wind. Antarctica receives 24 hours of daylight during the summer months, so sunshine helped to slightly warm the tents’ interiors above freezing.
In the background of the campsite above, you can see a strip of snow called a wind tail. Despite the arid climate in the Dry Valleys, the harsh winds carry and deposit snow accumulations, or tails, such as this one in the valleys. Daeschler and the team deliberately pitched their tents on the frozen snow to keep them anchored and secured against the wind.
Finding Fossils
Paleontologists like Daeschler study sedimentary rocks to reconstruct environments that existed millions of years ago. Above, Daeschler’s colleague Adam Maloof documents the sedimentary rock of the Aztec Siltstone, deposited 390 million years ago in what is now Antarctica.
During their expedition, the team collected fossils of a wide range of Middle Devonian aquatic vertebrates, including the tiny scales of agnathans and acanthodians, a wide variety of placoderm (above) plates, primitive shark teeth, early actinopterygians (rayfinned fish), and sarcopterygians (lobe-finned fish). Many fossils were visible and easy to find due to weathering on the surface of the rocks, but the team did minor excavations to uncover hidden fossils when they discovered fossil-rich zones.
Snow is infrequent in the Dry Valleys, so the rock surface is usually visible. Yet in the above photo of a research site above Beacon Valley, Antarctica, you can see that a surprising snowstorm lightly blanketed the rocks, making it especially challenging for the crew to locate fossil layers. They used whisk brooms to clear the surface. Next time, the scientists plan to bring their leaf blowers!
Coming Up Next…
Daeschler and the team plan to return to Antarctica in 2018 to explore more of the Aztec Siltstone. Their future field sites are about 50 miles from the area they explored in 2016/2017, on a part of the Boomerang Range near Alligator Ridge. Before departing from Antarctica, the team surveyed the Boomerang Range (below) by helicopter to search for accessible rock exposures, potential campsites, and a landing strip for supply flights.
Previewing the field sites also helped the scientists predict safety challenges and determine whether they need specialized equipment to access the rocks. The scientists may require snowmobiles for transportation between research sites, as well as training on crevasse safety to prevent falls into the deep fractures that form in glaciers.
This article originally appeared in the spring 2017 issue of our member magazine, Academy Frontiers.