Today's oceans are full of fish with fins that couldn't evolve into limbs like ours. So, who are our ancestors and where did they go? If you're a fan of MinuteEarth but don't yet support us...
========== You’ve probably heard that every bony land-dwelling
creature on Earth evolved from fish that grew limbs and crawled out of the water many million
years ago. And yet, over 99% of the fish in today’s oceans, lakes, and rivers have incredibly
delicate fins, formed by a series of spines covered by a thin web of skin. It’s hard
to imagine fins like those evolving into sturdy, weight-bearing limbs...because they didn’t.
But the fins of a far more foreign fish did. Very soon after bony fishes first evolved,
they branched into two groups – those with flimsy ray-type fins, and those with more
meaty appendages that were attached to their bodies by a single strong bone. At first,
those so-called lobe-finned fishes far outnumbered their ray-finned relatives, bu...