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Clarifications on frogs and single photons

submitted by Aard Vark

(oritteropo)
1 decade 1 year 8 months 1 week ago

Youtube description:

This is a good article for starters: http://physicsworld.com/cws/article/news/2012/sep/13/frog-photoreceptor-counts-photons

2 Comments

oritteropo

says...

The article he links for support is the same one I found, and it points out that the rods in both human and frog retinas can detect a single photon... but in humans there is a neural filter to prevent us detecting a single photon, we require 5-9 photons within 100ms to detect a flash.

I seriously doubt that frog vision works as he described in the original video, but clearly there could be some creature out there for whom his hypothesis was correct... and either way it was quite a fun talk, even if one has to substitute a robotic frog for total verisimilitude.

He says in the comments that he addressed this on his walk, but that the audio of that part was unusable!