killifish can adapt to life in a tree
Biologists in Belize and Florida have discovered that the mangrove killifish lives in trees when the water they usually live in has disappeared.
The London Telegraph said scientists found hundreds of killifish hiding in the rotting branches and trunks of mangrove trees.
Scott Taylor of the Brevard County Environmentally Endangered Lands Program in Florida told New Scientist magazine that the fish -- which normally live in mangrove swamps -- are able to change their bodies and metabolism to cope with life out of water. The changes are reversed as soon as they return to the water.