SMU Earth Sciences, Antarctica

Earth Sciences master’s student Chris Strganac, doctoral student Yosuke Nishida and Professor Louis Jacobs are part of a team traveling to Antarctica to discover 120 million-year-old mammal fossils from Livingston Island and other places around the Antarctic Peninsula.
They hope to link the evolutionary history of mammals across South America to Africa and Australia through ancient Antarctica when climates were warmer. So far in their journey, as chronicled by Chris, they have found ancient plants, but mammal remains have been elusive. They are still looking…

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Fossil hunting in Antarctica

Byers Peninsula was selected because it is ice-free, has sedimentary rocks that record a time when Antarctica was connected to Africa and South America (120 million years ago), and there are known plant fossils.

Mammal fossils are not known from this time in Antarctica, and the discovery of mammal fossils would reveal important clues to mammalian evolution.

The sedimentary rocks are derived largely by volcanism (volcaniclastic sediments), and volcaniclastic strata are highly variable. Despite the fact that no prior fieldwork recovered fossil vertebrates and that bone and plant usually require different environments to preserve as fossils, the variability of sediments has potential for preserving fossil bone. We aim to find it.

Beautiful weather greets us on the day we set to leave for Byers Peninsula. This part of the island, the largest permanent ice-free portion of the island, is, in fact, covered almost completely in snow. (One of the exposed rock formations is Cerro Negro, visible in the background of the photo. Cerro Negro is an igneous intrusion and unfortunately unfit for fossil preservation.)

Camping in Antarctica
Ten Zodiac trips were needed to bring our camping, field and personal gear to the island. With the aid of Team Barbeau, the assembly of the Scott tents and weatherport takes a couple of hours. Team Barbeau departs, and we take a few field team photos of “before.” After the photos, the first snowstorm hits us. The winds are high enough that it snows inside the weatherport. If it weren’t for Team Barbeau, we would still be setting up camp. We are very grateful for their help.

An important part of any camping is how to use the restroom, especially when leaving little to no impact. The climate is cold and near freezing, so if we buried our waste, we would preserve it. The nearby waters are not heavily trafficked, and we released the waste in the ocean. We used biodegradable bags, bio-bags, which dissolve in water (of course in the privacy of an additional Scott tent.) A red flag outside this Scott tent warns others not to enter. It’s not a good idea to pee in the bio-bag, as the bags dissolve very quickly.

Elephant seal fun
The ability to work on Livingston Island requires special permits, as the island serves as the mating grounds for Elephant seals. Elephant seals, we have learned, are quite interesting creatures. The young seals are cute; the adult males, with an enlarged nose giving them their name, are not so cute. It’s quite a metamorphosis that must take place.

Elephant seals make a variety of sounds. Some of them sound like burps that would make Homer Simpson blush, and some sounds are like hoots and hollers of a lively party down the beach. They are not aggressive, and the young are curious. The second day, we had a young elephant seal come up to the door of the weatherport and play with the handle straps of a walking pole. Several other young slept in the snow sleds. The third day we had a dozen young elephant seals, and the camp was beginning to look like a seal nursery.

The only real harm Elephant seals do is to roll around and crush our gear, or break a guideline keeping a tent up. When they move on land they look like giant slugs, since their legs have been modified to flippers and tailfins. We imagine they are more graceful in water.

The weather challenge
It was obvious from the beginning that a major obstacle to finding fossils would be the snow cover on the Byers Peninsula rocks. We have maps of the rock types on the surface, but snow covers at least 90 percent of them. Our plan was to prospect as much of the exposed rock as possible. If there were mammal fossils, the teeth and bones would not be larger than a few millimeters.

The weather provides other limitations. Good weather could and did change fast, so we did not stray more than a few kilometers from camp. In good weather, the temperature did not stray much from zero; there were winds, but no snow. Dry clothes and multiple layers were essential.

A few days into the trip, we experienced a snowstorm and the weather that seemed worthy and inviting enough for the Gentoo, Adelie and Chinstrap penguins that were now onshore. If it hadn’t occurred to us before, we certainly then realized, this is Antarctica.

When not out in the field and heated through physical exertion, we kept warm by making soups from scratch or “fruit miasma,” a concoction of heated fruits, butter, and brown sugar. We had plenty of Clementine oranges, apples and butter.

We learned, by experience, the definition of “post-holing.” Post holing is the act of leaving foot/leg prints after sinking into uncompacted snow. Good post-holes would come up to the waist. A one-mile walk on flat terrain could feel like three miles of climbing.

Rock hunting
On good-weather days, we would leave for day trips to examine the rocks. We found beautiful impressions of plant leaves, most notably ferns and angiosperms (flowering plants). Ferns are common in stressed environments, as in areas that had been demolished in volcanic ash flows. Angiosperms were not as abundant 120 million years ago.

After several days with no sign of fossil bones or teeth, we collected some rocks that might be broken down later. The resulting matrix may be examined under a microscope for teeth.

After day 8, we had covered the potential fossil-bearing outcrops close to the camp. The snow had melted some, and a few of the team members found hidden melt water as they post-holed through snow and ice. Luckily we were close to camp, and they could change into dry clothes. We dared not venture much further, as the dangers of hypothermia would be realized if we were far from camp.

We realized that the utility of working out of this camp on this part of Livingston Island was coming to an end. Compounded with the desire for a shower, a shave, and warmth (not to mention Bobby’s cooking), we were delighted to hear that we could be picked up in two days by the LMG. As an unexpected bonus, we now have a chance to examine 55 million- to 33 million-year-old rocks on Seymour Island, on the east side of the Antarctic Peninsula.

Team Barbeau once again helped us take down our camp and load the Zodiacs. It was disorienting, yet comforting, to feel the familiar “dock rock” on the LMG.

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