By Ted Daeschler
How far north is latitude 81°N? My wife had to lift that little round metal plate that sits at the top of most classroom globes to show a friend where I was last summer. My GPS indicated that our camp on northeastern Ellesmere Island in the Nunavut Territory of Canada was 632 miles from the North Pole. With the permission of the government of Nunavut, we were working on some of the most northern pieces of land on earth in search of 500-million-year-old fossils that might inform the earliest stages of vertebrate evolution.
What brought us to northeastern Ellesmere Island was curiosity about events in the early evolution of backboned animals, a taste for paleontological exploration, and long experience with working in the high Arctic. As always, preparation for the expedition was a significant endeavor, and our particularly remote location last summer required much logistical forethought. Importantly, we reviewed previous work and expected to build upon the work of geologists who had characterized the rock units of Cambrian age that are spectacularly exposed in the region of the Judge Daly Promontory.
Thanks to the Polar Continental Shelf Program of Natural Resources Canada, our three-day aviation odyssey from Ottawa—with stops at Iqaluit, Resolute Bay, Eureka, Carl Ritter Bay and Judge Daly Promontory, all before reaching base camp—went smoothly. At each stop we transferred to smaller and smaller aircraft, culminating in a helicopter that dropped us on a barren alluvial fan. This was our home for the next two weeks. My first impressions of the area were the steep relief compared to our previous field sites in the Arctic and the minimal signs of life that could eek out an existence in the harsh terrain of rock, ice, and water.
Our team was Neil Shubin and Mark Webster of the University of Chicago, Adam Maloof of Princeton University, and myself. From base camp we began to carry out plans that were first conceived months before. As always, the new terrain was a learning experience and physically demanding. Steep relief meant most of our walking was over rocky talus slopes and boulder-filled stream beds demanding careful attention. Cold streams gushed out of each side valley as 24 hours of sun converted snowfields and glaciers to rushing water.
Despite all of the planning, we were unprepared for some of the geological observations that we were confronted with during the first few days of field reconnaissance. The Cambrian-age rock formations were well exposed; they were the age we wanted and were formed of sediments that might encapsulate fossils that could inform our research interests.
But the earlier geological characterizations of the strata that we had consulted did not indicate the degree to which the rocks had been altered by high temperature and pressure during a long history of deep burial and structural deformation. We quickly realized that finding the delicate fossils of primitive vertebrates was unlikely in the rocks in the area.
Undaunted, we explored the variety of rock formations surrounding us, recharacterizing some of the stratigraphic details. At one site we actually did recover trilobites and some other Cambrian fauna, giving us the satisfaction of collecting new paleontological data.
For me, it was a great learning experience to focus on these older rock formations instead of the usual Devonian-age strata that have been the target of our research for two decades. It is always a privilege to explore such untouched parts of the earth and especially with a group of like-minded colleagues and friends.
Ted Daeschler, PhD, is the Academy’s vice president for collections, associate curator of vertebrate zoology, and associate professor, Drexel University Department of Biodiversity, Earth & Environmental Science.