Life in the Slow Lane: Ecology and Conservation of Long-Lived Marine Animals

A Review of Population Genetics in Sharks

Edward J. Heist

doi: https://doi.org/10.47886/9781888569155.ch12

Abstract. —This manuscript summarizes the results of seven studies of population genetics in sharks and several other studies that estimated levels of genetic variation in sharks. Investigations of population genetics in sharks are rare relative to studies in other fishes, and no analyses have been performed on any member of most orders of chondrichthyans. Allozymes and mitochondrial DNA typically reveal low levels of genetic variation within sharks, perhaps due in part to the demographic characteristics of sharks. Levels of genetic variation are significantly lower than those in marine teleosts. Sharks exhibit little genetic heterogeneity across wide geographic ranges; however, some stock structure has been detected both within and between oceans. Molecular characters have been used to confirm the presence of cryptic species and to support the synonymization of allopatric populations under a single species name.