Peripheral Vision

[P3D Dylan The Hippy Wabbit <spacey@xxxxxxxxxxxxx>]

Jim Crowell said:-

>One possible reason for having the schmutz in front of the receptors
>might be that it has to be inside the eyeball somewhere; if it were
>behind the receptors, they'd have to be closer to the lens, their angular
>subtense would be larger, angular resolution would be lower, etc.
>Probably not much, though.

I'd always understood that it's regarded as an accident of
evolution/development.  The schmultz is in front of the receptors because
that is where the first fishy eyes had it.  It would be a *lot* of work to
turn the retina round now, and probably blind several generations while it
happened.  Kind of a disadvantage.

Interestingly, squids and octopi have eyes which strongly resemble ours
through converging evolution.  The development that produces them is very
different though, and they have all the schmultz behind the receptors.
Lord knows what their little brains do with all that information mind.

I've just realised that I always seem to post to the threads that are
wandering off topic.  Maybe it's because I'm on the list to *learn* about
3D photos, so it's only the slightly off stuff that I can comment on.

Dave Spacey

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When you break rules break 'em good and hard.   - Terry Pratchett


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