FAU Study Finds Cavefish Rewire Neural Circuits for Light Aversion Over 100,000 Years
Updated
Updated · Nautilus · Jul 2
FAU Study Finds Cavefish Rewire Neural Circuits for Light Aversion Over 100,000 Years
2 articles · Updated · Nautilus · Jul 2
Summary
Science Advances reported that blind Mexican cavefish become hyperactive in light, while surface relatives become hyperactive in darkness, showing opposite behavioral responses to the same cues.
Brain imaging traced that split to the caudal posterior tuberculum, where neurons that respond to darkness in surface fish instead respond to light in cavefish.
Five-minute light-dark cycle tests and crossbreeding experiments showed the photokinesis trait is inherited, supporting a genetic basis for the cavefish’s light-averse behavior.
Researchers say that aversion may help cavefish avoid predator-exposed cave entrances and offers a vertebrate model for how evolution repurposes existing brain circuits rather than building new ones.