A Quantitative, Specimen-based Approach to Studying the Evolution, Paleoecology, and Paleobiogeography of Late Ordovician Brachiopods

Please join us for a special seminar this Monday February 26 at 3:30 pm in rm 106 Biology (note special location) presented by Colin Sproat, PhD:

A Quantitative, Specimen-based Approach to Studying the Evolution, Paleoecology, and Paleobiogeography of Late Ordovician Brachiopods

Colin D. Sproat

Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences

Brachiopods were the most abundant and diverse shelly metazoans in many marine environments throughout the Paleozoic. As such, they make excellent indicators of changes in the shallow marine ecosystem as a whole. For example, during the Great Ordovician Biodiversification Event (GOBE), a number of factors including high eustatic sea level and a diversification of phytoplankton in the water column contributed to the second largest biodiversification of life after the Cambrian Explosion. This led to the emergence of the strophomenides, rhynchonellides, and atrypides—groups that would dominate much of the later Paleozoic. By studying the effects of this event on the brachiopod fauna, we can gain better insight into the factors controlling this important event in the history of life.

Through the use of specimen-based quantitative techniques, evolutionary, paleoecological, and paleobiogeographical trends have been identified in the Late Ordovician brachiopod fauna of North America. In particular, distinct differences in the composition of the fauna that occupied the Appalachian foreland basin and northern Ireland and Scotland, and that of the basins and platforms of eastern North America emerged in the Middle and early Late Ordovician. By the late Katian, an element of the fauna from eastern North America began to diverge as it expanded into the equatorial intracratonic seas in terms of generic composition and shell shape to form a distinct epicontinental fauna. It is not yet clear whether these trends can be found in faunas elsewhere in the world or in other time intervals.

By continuing to describe new brachiopod faunas around the world and quantitatively analyze the evolution of previously described faunas, we can identify global trends in the evolution, paleoecology, and paleobiogeography brachiopod faunas. These trends could be applied to paleogeographical problems, enabling more accurate projection of the paleoplates from which paleomagnetic data is poor. These trends will also allow us to better understand the evolution and dispersal of the shelly benthic fauna in response to paleoenvironmental changes in the Paleozoic, and may even provide clues as to how the shallow marine benthic fauna will respond to changes in oceans of today.

Biography: Colin grew up outside Oakville, Manitoba in heart of the historical Metis homeland and received his BSc (Hons.) from Brandon University in 2010. It was there he started studying Early Paleozoic brachiopods. In 2010, he left the prairies to study under Dr. Jisuo Jin at the University of Western Ontario in London where he received his MSc in 2013 and PhD in 2017. He then travelled to Nanjing, China, to undertake a postdoctoral fellowship at the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences.