Monday, January 18, 2010

Dung beetles' secret superpower: ultimate night sight

...Dung beetles are particularly close to Warrant's heart because there are species of the genus Onitis that are almost identical but which fly at different times. The species that fly in daylight have eyes that are adapted to see in bright sunlight. The crepuscular Onitis alexis, which we are hunting, is adapted for the dim light of early morning and evening. There are nocturnal species too, such as Onitis aygulus, found a little further north. "The whole genus is extremely interesting," says Warrant. "They're a closely related group where all lifestyles are represented, and they have corresponding changes in their eyes and physiology to suit different light niches."

Warrant has compared these specialisations in different species of beetle, and also in bees and moths that fly at night. Now, with the help of a couple of mathematicians and Toyota's engineering experience, he has developed a remarkable camera system.

Car-makers are interested in night vision systems that might enhance safety, perhaps by monitoring a driver for signs of sleepiness or intoxication, or by scanning the road ahead for potential dangers. A few are already in use in top-of-the-range vehicles, but existing designs have some distinct drawbacks. At night there is about a billion times less light than there is during the day, and these cameras are simply not sensitive enough to make much use of it. So night-vision systems tend to rely on infrared illumination, which is invisible to our eyes. These cameras work in monochrome, and while they do reveal details we can't normally see, there is plenty of room for improvement. ...

Bees, beetles and moths have compound eyes with multiple lenses that together form a single image on an underlying array of light-sensitive photoreceptor cells. In theory these small lenses should be far worse at night vision than the larger human eye, but the way the cells in an insect's visual system process the light signals means they can make much better use of what little light is available. As light levels drop, the neuronal wiring in the insect's eye can either pool the signals from neighbouring photoreceptors or collect the signals for longer periods, Warrant says. Neither strategy is perfect: summing in time makes it difficult to detect movement while summing in space throws away spatial detail. It seems, though, that an insect's eyes can make a trade-off between the two strategies depending on how much light is available and how quickly the insect is moving relative to its surroundings. ....

via Dung beetles' secret superpower: ultimate night sight - tech - 12 January 2010 - New Scientist.

Check out the video showing improved night vision: http://brightcove.newscientist.com/services/player/bcpid1873822884?bctid=61281220001

Tangent about aliens: Imagine, for fun, that we are part of a very long term alien project to plant and harvest biological strategies on various worlds.  We were seeded.  Perhaps in less than 1,000 years we will be able to successfully reprogram our biology with traits we find in other life forms, as those who planted us do.

1 comment:

Cole said...

Yep, definitely don't want to have to deal with giant man-eating tarantulas AGAIN.