Forces Affecting Genital Morphology of Eastern Mosquitofish in the Everglades
Abstract
Eastern Mosquitofish are abundant fish in the Everglades. Some of their populations make annual, long distance migrations into temporary wetlands that dry out every year. Past work indicates differences in migration ability among fish from wetlands of different hydroperiod. Eastern Mosquitofish internally fertilize with a modified fin that acts as a penis-like “gonopodium,” which has been shown in other mosquitofish species to respond to the presence or absence of predators via altered size and shape. Data collected in 2019 reveals variation in gonopodium size and shape for Eastern Mosquitofish in Everglades wetlands that dry annually when compared to those from permanent water bodies (Lake Okeechobee and Gold Circle Lake). Our initial findings suggest that fish from permanent water bodies such as Lake Okeechobee possess shorter gonopodia that are blunter in shape than those from temporary wetlands. We hypothesize that these differences may result from differing predator densities in the different habitats or different migration regimes that the fish exist within. This work can be applied to Everglades restoration because Eastern Mosquitofish are an important food source for birds whose populations are explicit restoration targets. Understanding how their populations change, move across the landscape, and respond to predators is critical to maintaining high numbers in the preferred foraging areas of birds. Genitals are among the most rapidly evolving anatomical features of animals. Our work suggests that multiple environmental factors affect Mosquitofish genitalia, which contributes to understanding the combined influence of natural selection and sexual selection on these structures.
Faculty Sponsors
Dr. J. Matthew Hoch
Project Type
Event
Location
Alvin Sherman Library
Start Date
4-6-2021 12:00 PM
End Date
4-9-2021 12:00 PM
Forces Affecting Genital Morphology of Eastern Mosquitofish in the Everglades
Alvin Sherman Library
Eastern Mosquitofish are abundant fish in the Everglades. Some of their populations make annual, long distance migrations into temporary wetlands that dry out every year. Past work indicates differences in migration ability among fish from wetlands of different hydroperiod. Eastern Mosquitofish internally fertilize with a modified fin that acts as a penis-like “gonopodium,” which has been shown in other mosquitofish species to respond to the presence or absence of predators via altered size and shape. Data collected in 2019 reveals variation in gonopodium size and shape for Eastern Mosquitofish in Everglades wetlands that dry annually when compared to those from permanent water bodies (Lake Okeechobee and Gold Circle Lake). Our initial findings suggest that fish from permanent water bodies such as Lake Okeechobee possess shorter gonopodia that are blunter in shape than those from temporary wetlands. We hypothesize that these differences may result from differing predator densities in the different habitats or different migration regimes that the fish exist within. This work can be applied to Everglades restoration because Eastern Mosquitofish are an important food source for birds whose populations are explicit restoration targets. Understanding how their populations change, move across the landscape, and respond to predators is critical to maintaining high numbers in the preferred foraging areas of birds. Genitals are among the most rapidly evolving anatomical features of animals. Our work suggests that multiple environmental factors affect Mosquitofish genitalia, which contributes to understanding the combined influence of natural selection and sexual selection on these structures.
