Abstract Detail

Emerging Leader Lecture - Brian Atkinson

Atkinson, Brian [1].

Permineralized Floras Illuminate Cretaceous Plant Diversity and Evolution.

The vast majority of species that have ever existed on Earth are now extinct but their fossils remain vital for understanding the biodiversity we see today. The fossil record is the only data source that provides us with a direct window into the past. Although this chronicle of life is imperfect, it provides us with enough data to make meaningful inferences on evolution, especially when analyzed in integrative frameworks that place the fossils in broader phylogentic and macroevolutionary context. One of the primary ways we study fossils is through their morphology, which provides information on their biology, phylogenetic relationships, and broader patterns of trait evolution. Thus, fossils with exceptional preservation from critical time intervals are profoundly important for deciphering evolution in deep time. Deposits that preserve such fossils are often referred to as Lagerstätten. Classic examples include the Cambrian Burgess Shale for understanding the early Metazoan evolution and the Devonian Rhynie Chert for characterizing early land plant evolution. My lab uses fossils from Lagerstätten to illuminate Cretaceous (145-66 Ma) plant evolution and diversity. The Cretaceous saw dramatic evolutionary changes that lead to the initial modernization of terrestrial ecosystems. While the early diversification of angiosperms receives much of the spotlight for this interval, other plant groups were undergoing significant changes in diversity as well. My research program focuses on identifying and collecting fossil deposits containing plants that are three-dimensionally preserved down to the cellular level, a mode of preservation known as permineralization, in carbonate rocks. Analyzing permineralized fossils with a combination of tomographic and traditional sectioning techniques allows us to obtain unparalleled views of their external morphology and internal anatomy, which provides crucial data for precise systematic assessments, integration in phylogenetic analyses, and other biological inferences. Through field- and collections work, my research group has sampled localities from undersampled regions including the western coast of North America and western Antarctica, spanning much of the Late Cretaceous (100-66 Ma). These new and previously sampeled localities are providing novel information on several groups including bryophytes, ferns, gymnosperms, and angiosperms. We are only beginning to scratch the surface of the incredible plant diversity preserved in these deposits, which further our understanding of the Cretaceous origin of modern terrestrial floras.

1 - University Of Kansas, Ecology And Evolutionary Biology, 1200 Sunnyside Avenue, Lawrence, KS, 66045, United States

Keywords:
Fossils
Anatomy
Tomography
Gymnosperms
Angiosperms
Lagerstätten
phylogenetics.

Presentation Type: Special Presentations
Number: S08001
Abstract ID:683
Candidate for Awards:None