Mormyrids
Weakly electric fish use an active electrosensory system that is functionally analogous to the echolocation sensory modality in bats and cetaceans. Rather than use acoustic stimuli, weakly electric fish genearate Electric Organ Discharges (EODs) to create electric fields about their bodies. They use electroreceptors distributed across their bodies to detect these fields and the perturbations therein caused by objects with electrical properties different from water. EODs are also communication signals, containing information specific to species, sex, and even the individual. This remarkable sensory and communication system has evolved independently in two teleost lineages: the Mormyriformes of Africa and the Gymnotiformes of South America.
These fish, while primarily studied in a neuroethological context, provide a fascinating opportunity to study the costs of sensory acquisition from an ecological perspective. Since 2012, I have been studying the mormyrid species assemblage in Lake Nabugabo--a small body of water adjacent Lake Victoria in central Uganda. Like many native fishes in Lake Nabugabo and Lake Victoria, mormyrids are largely spatially restricted to hypoxic (low environmental oxygen) wetland refugia by predation pressure from the introduced invasive Nile perch (lates niloticus). However, mormyrids' electrosensory modality constitutes a significant energetic cost which other fishes exploiting these refugia need not accommodate. The majority of my research examines the effects of hypoxia on mormyrid distribution and sensory acquisition. Check out photos of my research and my travels in Uganda below!
These fish, while primarily studied in a neuroethological context, provide a fascinating opportunity to study the costs of sensory acquisition from an ecological perspective. Since 2012, I have been studying the mormyrid species assemblage in Lake Nabugabo--a small body of water adjacent Lake Victoria in central Uganda. Like many native fishes in Lake Nabugabo and Lake Victoria, mormyrids are largely spatially restricted to hypoxic (low environmental oxygen) wetland refugia by predation pressure from the introduced invasive Nile perch (lates niloticus). However, mormyrids' electrosensory modality constitutes a significant energetic cost which other fishes exploiting these refugia need not accommodate. The majority of my research examines the effects of hypoxia on mormyrid distribution and sensory acquisition. Check out photos of my research and my travels in Uganda below!