Blue Poison Dart frogs mostly live on the Rainforest floor. But because of rising sea levels rainforest floors will most likely be flooded so the frogs that live on the forest floor will most likely become darker to blend in while also developing aquatic features (tail, gills, and webbed feet). Also, these frogs would become darker to better fit the water and to hide from predators. The poison dart frogs that live in the tree would live on the floor with their counterparts since the trees would all be gone. So, this is how I imagine they would look before and after 1k years of evolution.
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