Loss of genetic diversity in Atlantic cod

Evolutionary Biology The collapse of the Northern cod population was one of the largest crashes of any marine vertebrate in the 20th century. Despite fishing bans, the species has yet to recover to historical levels. Kess et al. reconstructed these trends over the last century to illustrate how chromosomal structural diversity can mediate genetic, phenotypic, and demographic variation and how overfishing may have led to a loss of genetic diversity in Northern cod. They warn that removal of genomic diversity through overfishing may also reduce the buffering effect provided by phenotypic diversity in these populations, which increases the possibility of future collapse and alters the overall ecological function and composition of the Northwest Atlantic. Sci. Adv. 10.1126/sciadv.aav2461 (2019).