Figures from Wyatt et al., 2021

Morphological Variation

 

How much morphological variation is present at each taxonomic level in both the modern and fossil records?

I am interested in addressing this question for the family Heteromyidae, a rodent family whose fossil remains are mostly isolated teeth and are notoriously difficult to determine taxonomic identity. 

My paper, Using 2D dental geometric morphometrics to identify modern Perognathus and Chaetodipus specimens (Rodentia, Heteromyidae) looked at the shape variation between two genera and within species to assess how much shape information is needed to identify either genus or species.

This is the first step of many into exploring the amount of morphological variation at different taxonomic levels within the family Heteromyidae.

Functional Diversity

 

Do patterns of functional diversity follow patterns of taxonomic diversity through space and time?

Taxonomic diversity ebbs and flows in through the fossil record. Spikes in taxonomic diversity usually follow geologic events such as climate change or landscape evolution. 

The Middle Miocene Climatic Optimum is a particularly interesting time because it was a period of both unusually warm climate and increased tectonic activity in western North America as the Basin and Range formed. During this time, rodent diversity spikes to unprecedented levels. We don't yet know if the increase in the number of species accompanies an increase functional diversity. 

I plan to measure ecological function through 3D dental ecometrics to see how functional diversity changes through space and time. 

Figures from Smiley et al., 2020