Vertebrate faunal assemblages of the Late Cretaceous Western Interior Seaway in Manitoba

Kilmury, Aaron

Vertebrate faunal assemblages of the Late Cretaceous Western Interior Seaway in Manitoba

dc.contributor.author	Kilmury, Aaron
dc.contributor.examiningcommittee	Durkin, Paul (Earth Sciences)	en_US
dc.contributor.examiningcommittee	Nicolas, Michelle (Manitoba Geological Survey)	en_US
dc.contributor.examiningcommittee	Young, Graham (Manitoba Museum)	en_US
dc.contributor.supervisor	Brink, Kirstin
dc.date.accessioned	2023-01-18T02:15:17Z
dc.date.available	2023-01-18T02:15:17Z
dc.date.copyright	2022-12-26
dc.date.issued	2022-12-26
dc.date.submitted	2022-12-26T21:43:49Z	en_US
dc.date.submitted	2023-01-17T17:10:12Z	en_US
dc.degree.discipline	Earth Sciences	en_US
dc.degree.level	Master of Science (M.Sc.)	en_US
dc.description.abstract	The Late Cretaceous Western Interior Seaway (WIS) vertebrate community zonation hypothesis of two distinct biogeographic subprovinces based upon the distribution of tetrapod fossil occurrences is re-examined for the first time in over 32 years using presence-absence and relative abundance data from all represented vertebrate groups and temporal changes in community similarities throughout the Late Cretaceous examined for the first time. Vertebrate faunal assemblages of the Manitoba (MB) escarpment are compared with those of other coeval WIS assemblages across North America using three community similarity analysis methods, Sorensen’s Coefficient of Community, Percent Similarity, and Non-Metric Dimensional Scaling, to assess community zonation for nine intervals of Late Cretaceous time from the late Cenomanian to early Maastrichtian. At least two-part latitudinal community zonation with a migratory, gradational community boundary is supported throughout the Late Cretaceous, with three-part zonation supported by relatively high genus-level percent similarity values (25-50%) of south-central WIS localities and low values (<20%) of localities furthest north and south for the warmest time intervals, during late Cenomanian to early Turonian and late Coniacian to early Campanian times. Biases including size, geographic, preservational, and taxonomic are described from museum collections of MB escarpment fossils in order to present biogeographic results in an appropriate context, as well as to inform the current study and future studies of associated biases and make recommendations to counteract them with future work. A strong size bias towards the overrepresentation of large-bodied vertebrates from most Upper Cretaceous lithostratigraphic units of MB was revealed through museum collection surveys; therefore, a study of microvertebrate assemblages of the late Cenomanian to mid-Turonian Favel Formation was conducted to counteract this size bias and gain more information with regards to small-bodied vertebrate community members. Examination of Favel Formation microvertebrate fossils has revealed several significant discoveries, including stratigraphic and biogeographic range extensions for several taxa not previously recognized from the Favel Formation, estimation of relative position of the enigmatic northeastern WIS shoreline for three distinct time intervals, and discovery of new microvertebrate material.	en_US
dc.description.note	February 2023	en_US
dc.description.sponsorship	University of Manitoba (https://doi.org/10.13039/100010318), Master's Award for Indigenous Students Society for Sedimentary Geology (SEPM), Student Research Grant	en_US
dc.identifier.uri	http://hdl.handle.net/1993/37140
dc.language.iso	eng	en_US
dc.rights	open access	en_US
dc.subject	Biostratigraphy	en_US
dc.subject	Biogeography	en_US
dc.subject	Community Similarity	en_US
dc.subject	Microvertebrate Fossils	en_US
dc.title	Vertebrate faunal assemblages of the Late Cretaceous Western Interior Seaway in Manitoba	en_US
dc.type	master thesis	en_US
local.subject.manitoba	yes	en_US
oaire.awardNumber	RGPIN-2021-03756	en_US
oaire.awardTitle	NSERC Discovery Grant	en_US
project.funder.identifier	https://doi.org/10.13039/501100000038	en_US
project.funder.name	Natural Sciences and Engineering Research Council of Canada	en_US