A new study in the PLOS Biology journal makes a rather academic-sounding proclamation in its headline: "The aesthetic value of reef fishes is globally mismatched to their conservation priorities." Translating that into more layman-friendly terms: We have to look out for the ugly fish, or they might die out. The research published Tuesday notes that reef fish considered to be physically attractive aren't under as much of a threat of extinction as their more unsightly counterparts, who fall more into the "endangered" category. "There is a need for us to make sure that our 'natural' aesthetic biases do not turn into a bias of conservation effort," study co-author Nicolas Mouquet of France's University of Montpellier tells the Guardian. Mouquet and his colleagues first surveyed 13,000 people who'd viewed nearly 500 photographs of various ray-finned reef fish, instructing them to rank the aesthetic attractiveness of the fish.
The researchers then plugged those results into an AI system to apply it to more than 2,400 of the most well-known species of reef fish. What they found was that bright, round, and vibrantly colored fish, such as the queen angelfish, striped cowfish, and butterflyfish, were more often deemed "beautiful" by those surveyed. "High color heterogeneity (quality) and well-delineated patches of contrasted lightness ... makes them pleasant to [people]," Mouquet tells Deutsche Welle. On the flip side were more "drab" fish, such as the telescopefish and round herring, which were found to be "uglier" by respondents. Where survival as a species comes into play: The beauty queens of the group are more similar genetically to other fish in the sea, meaning they're less "evolutionary distinct"—and therefore less likely to go extinct.
The ugly fish were "more ecologically distinct, at greater ecological risk, and listed as 'threatened'" on the International Union for Conservation of Nature's Red List, a guide on the global status of biodiversity, per the Guardian. The less-attractive fish also ranked higher from a "commercial" standpoint—i.e., they're more likely to be overfished. The outlet notes this is due to them often living in the ocean's water column and hiding out in more homogeneous habitats. Mouquet says this conservation bias tied to attractiveness has come into play in studies of other species—for example, vertebrates such as mammals and reptiles are more often the focus of conservation efforts than invertebrates like worms or insects, per ZME Science. Mouquet hopes that by understanding these biases, scientists will be better able to combat species loss. (More discoveries stories.)