Richard Dawkins shows how flatfish disprove intelligent design, and Sir David Attenborough shows how flatfish develop from normal-looking fry that have eyes on both side of their heads into fish that have eyes on only one side.
A really good transitional fossil was recently discovered that shows how these fish might have evolved their peculiar shape from “normal” fish.
I would love to know the genetic basis for how these fish develop.
They start out as typical fry, but then the code within their DNA causes them to develop into something quite bizarre.
Think about how strange these fist are.
Imagine if you bought a puppy with eyes on both sides of its head, and then as the puppy matured, one eye began to migrate over to the other side. And then the dog started crawling around on its side/
That’s about what happens with flatfish.
But as strange as is their adaptations are, they are quite successful. They have been around for 50 million years, and there are anywhere from 400 to 600 species of them living on the planet at this time.
An intelligent designer would have made the flatfish like rays and skates, which are actually flattened out sharks. Skates and rays born flattened out and move very efficiently in the water. Flatfish really don’t move so efficiently in the water, and they don’t move very far from the sand in which they normally bury themselves. Although many rays do bury themselves in the sand, manta rays swim in open water for great distances. There is not a single fish in the flatfish lineage that has evolved to be anything like a manta ray.
It’s probably because of the historical legacy of having evolved this body type that flatfish will be stuck on the ocean floor.
If they could evolve greater efficiency as swimmers, they might be able to go a different route.
And one could imagine that someday there might be an efficiently swimming flatfish that is able to take to the water column in search of prey. It would likely still have the eyes on one side of its head, and it would truly be a bizarre creature to behold!