Category: Research

All of the fish pictured here are in the family Mormyridae and can produce and sense electric fields. In the top group of fish (subfamily Mormyrinae), electric discharges have evolved quickly, resulting in dramatically different pulses of electricity among closely related species. In the bottom group of fish (subfamily Petrocephalinae), all of the species have similar pulses. The difference arises because the top group has the anatomical features needed to exploit the signal space, such as the anatomy needed to make different pulses and the sensory and analytical ability to perceive small differences in pulse shape.

Among mormyrid fish, conversation is literally buzzing. Using specialized electricity-emitting organs in their tails, these African natives string together short shocks into a primitive analog to Morse code, says study coauthor Bruce Carlson, a neuroecologist at Washington University in St. Louis.

A scientist who studies the small, silver elephantfish may have stumbled on the key to speciation, the process that allows one species to evolve into two or more. And it’s all about developing new sensory perceptions.

The rivers and lakes of Africa are filled with conversations that you cannot hear or take part in. These chats are conducted by fishes called mormyrids or elephantfishes, which can produce and sense electric fields.

Bigger brain regions caused a ‘big bang’ in the evolution of African electric fish, new research has shown.

Carlson, PhD, assistant professor of biology in Arts & Sciences, is studying the African family of weakly electric fishes called the Mormyridae, or mormyrids.