Antarctic dinosaurs

Antarctica does not immediately come to mind when thinking about places to go to hunt dinosaur fossils, but there are seven dinosaur species known from the continent that sits over the south pole.

Geological expeditions to Antarctica are of course limited by the continental ice sheet that covers 99% of the land surface, and exposures of potential fossil-bearing rock are limited to exposures along the coastlines and on mountain slopes, so the full extent of Antarctica’s fossil treasures may never be known.

Of course, the continent was not entombed in ice when the dinosaurs roamed Antarctica’s landscape; although Antarctica has been sitting at its polar latitude for the last hundred million years, and dinosaurs would have had to adapt to six months of darkness, the climate during the Cretaceous Period was warmer, and Antarctica hosted cycads, palms and ginkos.

Photo Credit: Nathan Smith. Caption: Kevin Kruger, Peter Barrett and Nathan Smith (from left) excavate dinosaur bones in 2003-04 on Mount Kirkpatrick. http://antarcticsun.usap.gov/antarcticsun/science/images/dinosaur%20excavation.jpg

Serendipity with a backhoe

This is a story of what happens when construction workers have some appreciation for interesting rocks and fossils they come across in the course of their daily tasks:

While excavating oil sands in a mine near the town of Ft. McMurray, Alberta, Canada, a heavy machinery operator uncovered the skeleton of a plesiosaur, the extinct, long-necked reptile that inhabited Mesozoic seas.

The skeleton had been fragmented by its excavation by backhoe rather than small hammers, chisels and brushes, but when pieced back together, it was judged to be 80% complete.

The find is significant because it is the earliest North American occurrence of a plesiosaur, extending the known geologic range of these animals to the early part of the Cretaceous Period and this find also expands the known geographic range of plesiosaurs in North America.

Reference: Journal of Paleontology November, 2009, Earliest North American occurrence of a plesiosaur

Photo credit: http://www.dinosaurjungle.com/focus_plesiosaur.jpg. For more on plesiosaurs, go to this site or click on today's title.