Meeting Abstract

90.2  Sunday, Jan. 6  Family-level analysis of exploited and at-risk ray-finned fish species shows high potential loss of biodiversity CHANG, J.*; EASTMAN, J.M.; ALFARO, M.E.; University of California, Los Angeles; University of Idaho; University of California, Los Angeles jonathan.chang@ucla.edu

Commercial harvesting of ray-finned fishes is both intense and widespread. The distribution of this pervasive exploitation and its attendant risk of extinction with respect to phylogeny is not currently well-understood. Previous studies have shown that clustered extinction increases the loss of trait diversity, which have both short-term (lower yield, reduced ecosystem services) and long-term effects (lost evolutionary history, biodiversity). We used several previously published phylogenies of families with exploited species and constructed additional phylogenies using phlawd. Species on these phylogenies were matched to exploitation and extinction risk data collected from fishbase.org, the IUCN Red List, and the Sea Around Us Project. Our results show a highly significant clustering of extinction risk and exploitation among many of the fish clades examined. Additionally, the pattern of these clustered extinction risks would lead to a significantly increased loss of evolutionary history compared to a pattern of random extinction, maximizing the potential threat to biodiversity. We also analyzed the rate of body size evolution using auteur, and found that in some families species that are at risk for extinction or are experiencing exploitation pressure tend to enjoy a significantly faster rate of body size evolution. This finding, in conjunction with the threat of a high loss in evolutionary history, suggests that commercial harvesting of fish is pruning away particularly exceptional branches on the fish tree of life.