Subterranean Fishes of the World

5625

2022

AIM 2022

31

In certain animal species, ranging from arthropods to mammals, collective behavior is repeatedly lost to meet the ecological demands. Recent comparative genomics studies involving honeybees and the Mexican cavefish revealed that the dysregulated genes in these social-attenuated populations are significantly enriched across the genome in homologs of autism risk genes. Although these risk genes are expected to reduce sociality by acting on brain wiring, our group recently found that an evolved asocial population retrieves the ability to socialize in response to environmental interventions: spatial and dietary. Spatial and dietary interventions provide sensory input and nutritional intake to the brain, respectively. However, there is a significant knowledge gap regarding the genetic and molecular mechanisms mediating this environment-social plasticity axis in general. Here we present our latest update on the spatial and dietary effects on A. mexicanus social affinity. In the dark vision-deprived condition, the familiar and unfamiliar spatial stimuli induced different social responses between surface fish and Pachón cavefish: surface fish reduced the social affinity duration whereas cavefish increased the duration under the familiar environment. This result suggests the opposite regulation in the social-regulatory network between surface and cavefish while cavefish’s social affinity is still inducible. The ketogenic diet, inducing ketosis where the liver release ketone bodies into the plasma, also increased social affinity in cavefish. The level of social affinity observed under the ketogenic diet treatment was similar to the level seen in the Pachón cave 2019, implying cavefish in nature may also be under ketosis. Accordingly, supplemental treatment of the ketone bodies also increased social affinity in cavefish. We will share the updated result including the change of gut microbiota according to the diet and dietary influence in other cave-type behaviors.

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