UV light study

Alice

Arachnoangel
Old Timer
Joined
Sep 29, 2006
Messages
976
VERY interesting! however, tarantulas have very bad eyesight, so i wouldn't think it applies to them as well... pity, we'd have more now rare species around if that would work for ts.
uh, does anyone actually know if they can see uv light? or is anyone willing to experiment with it?
 

C_Strike

Arachnobaron
Old Timer
Joined
Jun 8, 2005
Messages
445
The bad eyesight might simply be attributed to sight of the normal color spectrum, although unlikely, maybe they can pick up UV. Many inverts do, and many spiders do, so it seems completely reasonable for a family of spiders to do so too.
 

Arachno~Raver

Arachnopeon
Joined
Dec 21, 2006
Messages
43
thanks for this info i was a very interesting read and i hope that this reasearch will work with T's as it will help to stop the extintion of species
 

Code Monkey

Arachnoemperor
Old Timer
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Jul 22, 2002
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3,786
The bad eyesight might simply be attributed to sight of the normal color spectrum.
The bad eyesight is attributed to 8 small lenses in fixed positions (and generally arranged in for a radial view) with a fixed focal length which is set within a few inches of the spider.

In other words, something like a Poecilotheria, with it's more forward mounted & larger pair of eyes, might have some visual accuity intended for hunting at somewhat of a distance, but the majority of tarantula eyes are selected for a broad spectrum glance at their surroundings that would let them detect a large "predator" within feet and prey movement within inches, but certainly cannot form detailed images.

As a comparison, consider the honeybee that has 5000 separate omatidia and is estimated to only have about 1% of the visual accuity of humans. While it's not one to one to compare the simple eyes of a tarantula to the omatidia (the individual components of a compound eye), considering the size of a tarantula's simple eyes, the comparison is not totally invalid. Also, consider the jumping spider, a spider known to be able to distinguish images, and how large its eyes are both compared to its body as well as simpy to a T. blondi, then consider anatomical analysis showing the areas of the brain dedicated to eyesight in jumpers, etc.

OTOH, what people discount too much is whatever sort of "vision" they get from their hair sensory array. They can probably detect detailed and minute changes in air currents, chemical gradients in the air, and substrate vibrations that more than compensate for this lack of light sensory capabilities in the scope of the their "world".
 
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