Signal Evolution in Electric Fish
This page describes research completed during my Master's thesis at University of Toronto.
Loss of an Anti-Predator Adaptation
Gymnotiform fishes generate species-specific electric organ discharges (EODs), which they use for both communication and navigation. Gymnotus, the banded electric knifefish, is a diverse genus with a range that extends from Argentina to southern Mexico and includes species distributed both east (cis-Andean) and west (trans-Andean) of the Andes. I proposed a new molecular phylogenetic hypothesis for 35 Gymnotus species based on two mitochondrial (cyt b and 16S) and two nuclear genes (RAG2 and Zic1). I found that the trans-Andean species are distributed in four distinct lineages with varying amounts of divergence from their closest cis-Andean sister taxa. I also evaluated EOD phase number evolution in Gymnotus and found a trend for reduced phase numbers in both cis- and trans-Andean regions.