Marine fossils from the Cretaceous of Manitoba: How fossil assemblages can give insight into the major changes marine communities experienced during major climate changes in the past

Speaker: Aaron Kilmury, Department of Biology, Brandon University

Abstract:

The Late Cretaceous (100-66 My) Western Interior Seaway (WIS) vertebrate community zonation hypothesis is re-examined for the first time in over 32 years, and temporal changes in community similarities throughout the Late Cretaceous examined for the first time.

Vertebrate faunal assemblages of Manitoba (MB) are compared with those of other time equivalent WIS assemblages across North America to assess community zonation for nine intervals of Late Cretaceous time.Biases are described from MB escarpment fossil collections in order to inform the current study and future studies of associated biases.

A strong size bias towards the overrepresentation of large-bodied vertebrates was revealed; therefore, a study of microvertebrate assemblages was conducted to counteract this size bias and has revealed several significant discoveries, including new microvertebrate material. Comprehensive descriptions of vertebrate biostratigraphy, biodiversity, biogeography, and fossil collection biases employing all vertebrate groups demonstrates the importance and scientific value of the fossil assemblages of southwestern MB.

Biography:

Aaron Kilmury recently began instructing paleontology courses at Brandon University and is a former Royal Tyrrell Museum of Palaeontology Preparation and Field Technician and a recent master’s of science graduate who studied marine vertebrate paleoecology and biogeography at the University of Manitoba (U of M). The recently published first main chapter of his thesis examines biogeography of marine vertebrates (fish, sharks, birds, and reptiles) of the Late Cretaceous (66-100 million years ago) Western Interior Seaway of North America in relation to Manitoba fossil assemblages in order to investigate the impact of long-term climate changes on marine vertebrate communities in the ancient past. Aaron recently finished the second main chapter of his thesis investigating Late Cretaceous fossils of small-bodied vertebrates of Manitoba with an accompanying open-access article published through PeerJ. His second main chapter involved other university students in microfossil sorting, as well as middle and junior high school students, to increase their interest in paleontology and other Earth Sciences. A colour image, microvertebrate fossil sorting guide made by Aaron and U of M student volunteers was completed earlier this year and made available online to help increase inclusion and diversity in paleontology activities and counteract the common size bias of underrepresentation of small-bodied vertebrate fossils.