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This fish… can change its sex… based on who’s around it. Not randomly. Not slowly. Triggered by its social group. It’s called the bluehead wrasse. And in every group… there’s one dominant male. Bright. Aggressive. In control. Surrounded by females. But here’s where it gets strange. If that male disappears… everything changes. The largest female doesn’t wait. Within hours… her behavior shifts. Becoming more aggressive. Taking control. Then over days… her body transforms. Colo