4 ms·
Robins can see magnetic fields, but only if their vision is sharp
- drKarl 16y agoIt sounds like a natural Augmented Reality HUD. Interesting...
- sliverstorm 16y agoNot nearly as interesting as the fact that it only happens in the one eye, not the other!
- Sharlin 16y agoIt probably happens in both eyes but only the left hemisphere (handling input from the right eye) is wired to do the pattern recognition needed.
- pavel_lishin 16y agoI wonder if there's any "left-eyed" robins out there.
- ars 16y agoThe reason it works is because it's only one eye. The brain compares the two eyes, and if it sees a difference it knows it's because of the magnetic field. If it was both eyes it would not be able to tell the difference between magnetic images and regular ones.
- hugh3 16y agoQuestion: if this ability is so easy to evolve, why don't we all have it? Any animal that moves around a lot could probably benefit from being able to directly sense the Earth's magnetic field.
- jbert 16y agoBecause you're not descended from creatures who migrated sufficiently often or far for this to be a significant advantage in their reproductive efficiency.
- Tamerlin 16y agoI just wrote something similar in another reply. :)
- jared314 16y agoThere must be a trade-off in there somewhere. Precise binocular vision must be useful for something too.
- Tamerlin 16y agoHunting, maybe? If you're a creature like, say, a human, who is pretty much outclassed by every critter out there in terms of physical prowess, then the people most likely to survive are the ones that are good at hunting. The ones that hunt only up close don't need as much precision as ones who hunt at a distance (thrown spears, bow & arrow, that sort of thing), but having good depth perception will give a hunter a survival advantage over someone who does not. So, members with better binocular vision will tend to survive longer than ones who don't. With today's agriculture-oriented societies, the hunting advantage isn't as critical to survival, of course.
- sprout 16y agoWell, seeing into the magnetic spectrum you would lose some ability to distinguish color in our visible spectrum, and our visible spectrum seems excellently adapted for distinguishing between various plant species, which is essential for the 'gatherer' side, and finer visibility in our spectrum also aids in hunting - the magnetic part of the spectrum doesn't add a lot of information.
- Tamerlin 16y ago
- TallGuyShort 16y agoI wonder if the slanted light/dark bands has anything to do with why birds seem to tilt their heads as they look around.
- thefool 16y agoThats probably because (most) birds don't have binocular vision and thus need to turn their head to get a better look at you.