slapped himself to the side of a rock as I was snorkeling by,
an evasive trick he must have learned from Han Solo.
The freaky feature for me is the two eyes on the same side of the body, at what looks like a haphazard angle. They seem to track separately, like a chameleon. (I post a detail crop of the eyes below)
Stranger still, the fish does not start out that way. As a young fish, it has eyes in the regular place, but then one migrates over.
But it doesn’t go around the outside, it moves through the skull to the other side!
Talk about looking inward to one’s soul… That’s a period of serious introspection… and neuronal rewiring. But with independent visual fields, it might not be as dramatic as what the common tadpole is going through right now in various Spring ponds.
Frogs have binocular vision to catch flies. Tadpoles have eyes on the sides of their heads, a common difference between predator and prey.
The eyes move during adolescence, and so the visual system in the frog’s brain needs to be rewired. The nerves from half of the tadpole’s eyes must remap to the other half of the brain to properly process the new overlapping field of view.
One gene triggers this rewiring of the optical crossroad junction midway through life. I wonder if they have to learn how to see and focus anew, with visual feedback modulating the axon growth cone?
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