Bird's Eye View

My main man on the frontlines of the interweb, H.R.M. Idle Eyes The See-Thru, sent me this interesting gem about turd bombers (and to think, I chose it over the animal penis restaurant and lesbians). Over four decades, no one was able to prove it possible, but now evidence suggests that birds can actually "see" the lines of the Earth's magnetic field. Of course, they still can't see windows for shit.

Cryptochromes are a class of light-sensitive proteins found in plants and animals, and are thought to play a role in the circadian clock, in regulating plant growth, and timing coral sex. Just a few years ago it was found that they were present in the retinal neurons of migratory garden warblers, and that these cells were active at dusk, when the warblers were performing magnetic orientation. Cryptochromes have not yet been made in the lab and obtaining them is difficult, but a related molecule – a carotenoid-porphyrin-fullerene triad – with similar chemical properties to cryptochromes is sensitive to weak magnetism.

Like cryptochromes, the CPF molecule is stimulated by light of specific wavelengths to produce two free radicals. Control over the concentrations of each free radical in a solution of CPF was accomplished by applying a magnetic field. Most chemists would have predicted that the extremely weak magnetic field could not possibly have an effect on molecules because the electromagnetism would be completely swamped by the molecules' inherent energy. But not their influence on migrating birds.

Birds appear to orientate at dusk, and cryptochromes form their pair of free radicals when "activated" by the blue light typical of dusk. The concentrations of each free radical would be controlled by the Earth's magnetic field, which is known to vary with latitude. As a result, the radicals would bind in varying degrees with other signalling molecules, depending on how far north or south the animal is. However, this creates debate about how birds process their "magnetic sense".

One belief is that they have an additional layer to their vision, which when switched on allows them to visually "see" the Earth's magnetic field. The situation would be similar to "head-up displays" in fighter jets and some cars, where transparent screens displaying information are built into windscreens. Must be how they are able to crap on everything so well.

And in other avian news, I was totally disappointed to find out this was a story about birds.