In its youth the flat-fish is symmetrical with one eye on each side. However, as the body matures, one eye “begins to glide slowly round the head.”
To see why, we must remember that muscles first appear in the Cambrian explosion.
“Many life forms with essentially new body types appeared quickly and without precursors in the Burgess Shale in Kicking Horse Valley in British Columbia.”
They conclude, “there is something besides mutations and survival of the fittest needed to explain evolution.”
We have seen the absurdly low quality of this individual’s video. But there is much more. I have added timecodes in square brackets for easier reference.