
Samantha Levell
Visiting Assistant Professor of Biology
Western Oregon University
THE EVOLUTION OF THE PLACENTA
In the Fish Family Poeciliidae
I am interested in studying the evolutionary consequences of placentation. In the livebearing fish family Poeciliidae, placentation has evolved independently at least eight times. Additionally, for each species with a placenta, there is (in most cases) a sister species lacking a placenta. I aim to identify costs and benefits to this reproductive strategy as well as potential mechanisms of speciation resulting from parent-offspring conflict associated with placentation through testing predictions of the viviparity-driven conflict hypothesis.
A corollary of the shift towards internal, post-zygotic maternal provisioning is that there is a shift away from pre-copulatory sexual selection, and towards post-copulatory sexual selection. I am interested in investigating the potential for sperm competition and cryptic female choice (post-copulation) and examine how these factors influence paternity and subsequent maternal allocation based on paternal genotype. I am working on these questions in species with and without placentas to look for differences between species with different reproductive modes.


ABOUT ME
I grew up in Florida, surrounded by incredible fresh and saltwater ecosystems. Through my adventures in these habitats, I developed a love for fishes and fish keeping. I began my career as a scientist studying the Least Killifish, Heterandria formosa, as an undergraduate in Joseph Travis' lab at Florida State University. I continued my passion for researching fishes during my PhD student in David Reznick's lab at the University of California, Riverside. Currently, I am a biology instructor at Western Oregon University. I teach Ecology with Lab and Marine Ecology with lab. I also teach introductory Biology courses and their associated labs.
