Main Research Projects

We currently focus on two main projects, both using livebearing fishes as model systems.

Ecology and evolution of the Amazon molly: Why sex?

Amazon molly
The evolution and maintenance of sex are still major question in biology. We are using a unique fish to address these problems. The Amazon molly (Poecilia formosa) is an asexual fish that reproduces via gynogenesis. Amazon mollies do not have sexual recombination. They also have no males – it is an all-female species. Amazon molly females produce diploid eggs that develop into clonal copies of the mother. The development of the embryos needs to be triggered by sperm. The sperm are provided by males of several other species. We use this mating system to make direct comparisons between asexual and sexual animals living in the same habitat.

Biology of the Cave molly: Life and love in the dark

Cave molly


Very few vertebrates live in caves. The ones that do have unique adaptations to cave life, but at the same time they are in the process of loosing traits that used to be adaptive on the surface. We use the Cave molly (Poecilia mexicana) to study these processes. Cave mollies live in a Mexican cave, which in addition to darkness, also features high levels of toxic H2S in the water. We use this system to study how cave mollies deal with darkness and toxic water and how they evolve into cave organisms.


See a movie of cave mollies in their natural habitat

 See a movie of a giant water bug (Belostoma sp.) feeding on a cave molly

 NSFLogo


Open Projects for Undergraduates