Fish in a tree, how can that be?

Not just in Dr. Seuss books, this is for real. Scientists slogging through swamps in Belize and Florida found hundreds of mangrove killifish lined up inside rotten branches. The fish can last for months inside trees when nearby pools of water go dry.

To survive out of water, the fish need to make drastic changes in their metabolism and physiology. They alter their gills to retain water and excrete nitrogen through their skin. In a perhaps unrelated adaptation, female killifish can reproduce without needing males.

Now there's a stereotype-buster for you. More evidence in support of the pioneering but controversial biological work of Dr. Seuss. Anyone want to join me in my expedition in search of the last truffula tree?

hat tip: Brad