The journal Brain, Behavior, and Evolution has just released a special issue on the nervous systems of cartilaginous fishes (sharks, skates, rays, and chimeras). The six research articles contained in the special issue both summarize and greatly expand what’s known about elasmobranch brains.
Dr. Kara Yopak, an elasmobranch nervous system expert who served as the editor of this special issue, explains why increased knowledge about the brain function of one of the most basal groups of vertebrates is fascinating and important:
“Although is a common misconception that sharks are small-brained and operating from a limited set of behaviors, they actually have relative brain sizes that are comparable to birds and mammals, a battery of highly developed sensory systems, and an extremely sophisticated suite of complex behavioral and social repertoires. Research in this area allows us to combat these preconceived notions about the shark brain and develop a better understanding of how the shark nervous system has evolved, how these animals receive and process information from their environment, and the implications these variations have for evolutionary adaptations in the brain across all vertebrates, including humans.”
The research featured in the special edition includes methods as diverse as histology, MRI, electrophysiology, and behavioral ecology. The implications of this research are vast, including the potential for species-specific bycatch reduction in fisheries which accidentally catch sharks, the development of more effective shark repellents, and an increased understanding of the evolution of the vertebrate brain. I encourage any scientists or shark enthusiasts interested in fisheries, evolution, or neuroscience to check it out.