QCBS Students

Alexandre Demers-Potvin

McGill University
M.Sc. candidate

Supervisor: Hans Larsson
Start: 2017-09-01
End: 2019-04-01

The Schefferville Argillites, a Window into the Cretaceous Biodiversity of Northern Québec
Québec contains a tiny area of Mesozoic rocks near the Schefferville iron mines. These are argillites deposited in a lake bottom in the middle of the Cretaceous period. The few fossilized organisms that have been excavated during a handful of expeditions are insects and plants, the latter of which constitute the most complete terrestrial flora from the Cretaceous of Eastern North America. I wish to draw a clearer picture of this mysterious ecosystem by undertaking more digs around Schefferville. The excellent preservation of the fossils already available gives me hope of discovering and describing new species representing other taxa, such as vertebrates or other arthropod classes. Then, I aim to unite all Schefferville collections to evaluate this paleoecosystem's diversity (alpha diversity) and to compare it with that of coeval North American ecosystems (beta diversity). An increased sample size of fossilized leaves will also lead to more robust climate estimates for this time period. At a more global scale, an increased understanding of this community's ecology will shed more light on an epoch of the Mesozoic era that has witnessed the radiation of angiosperms and of many insects, laying the foundations of our modern ecosystems.