From Mating to Maternity: The confluence of reproduction, stress, and cognition in a live-bearing fish

Summary

All animals on Earth rely on reproduction for the continuation of their species, employing a wide-variety of reproductive strategies to produce their young. Live-bearing fishes from the family Poeciliidae are a prime example of the reproductive diversity which can exist within a single family; different poeciliid species display varying degrees of maternal-fetal exchange and communication during pregnancy based on the presence or lack of a placenta. Female poeciliids also employ additional reproductive adaptations that facilitate live-bearing reproduction, including: complex mate-choice strategies, long-term sperm storage, and superfetation (the ability to carry more than one brood of offspring simultaneously). In this thesis, I follow the female developmental trajectory from mating to maternity by investigating several reproductive adaptations in the live-bearing, non-placental, and superfetatious fish Poeciliopsis gracilis. The aim of my research is to better understand how these adaptive traits allow female poecillids to cope with challenges related to mating, fertilization, and pregnancy.