
Factors Influencing Phenotypic and Genotypic Polymorphism in Male Body Size in the Swordtails (Xiphophorus: Poeciliidae: Pisces): In swordtails variation at the P allele controls most of the variation in body size in most species. A variety of studies are addressing behavioral correlates of the P allele, the maintenance of its variation in nature, and the historical patterns of preferences in females and P alleles in males in the clade of northern swordtails.
We recently identified the P gene as the melanocortin 4 receptor, and showed that: (i) there is copy number variation in mc4r, (ii) Y-linked alleles result in non-functional receptors, and (iii) there is a correlation between male size and copy number of Y-linked alleles (Lampert et al. 2010). Current studies with Professor Manfred Schartl (Wurzburg Univ, Germany), Dr. Hans Hoffman, and Dr. Alex Jordan (Max Planck Institute) are exploring the molecular genetics, neurobiology and behavioral evolution of this system.
The Amazon Molly

Behavioral Factors in the Maintenance of an Asexual-Sexual Species Complex of Mollies: The Amazon molly, Poecilia formosa, is an all-female species that reproduces clonally, but females must mate with males of the sexual species, P. latipinna, to acquire sperm necessary to trigger embryogenesis. The main question of our research asks, why would male sailfins mate with female Amazons if there is no reproductive benefit to the male? Click here for one of the answers. Much of this work is in collaboration with Dr. Ingo Schlupp of the University of Oklahoma.
Frog-eating Bats

Trachops cirrhosus, the fringe-lipped or frog-eating bat, is an eavesdropping predator that locates anuran prey by their calls. Not only do these bats rapidly learn to associate particular cues with the palatability of their prey, they can do so by observing the behavior of other individuals. May Dixon, Claire Hemingway, and STRI Staff Scientist Dr. Rachel A. Page (a former lab member) are investigating the cognitive ecology of T.cirrhosus, including learning and memory, as well as predation on multiple types of prey, social behavior, and echolocation. Dr. Wouter Halfwerk (VU University of Amsterdam) is investigating multimodal foraging strategies in Trachops.
Chytrid
Sofia Rodriguez is studying the effect of the chytrid fungus (Bd) on the behavior and genetics of tungara frogs. As part of tracking the spread of chytrid she led an expedition into Darien Gap in summer 2014. Click here for a video and more information.