Good morrow, gentle folk.
I thought I’d elaborate on what I was talking about back on Wednesday eve. Jumping spiders are truly tough to beat in any posing contest amongst critters. I think that comes in part because of the size of their primary two eyes, which are large enough to throw up reflections of their surroundings. Think anime eyes and their exaggerated expressions.
The other part is their apparent curiosity. Again, this is connected to their large eyes. Jumping spiders, like most other spiders, have a LOT of eyes – usually six or eight. Now, all but two of these are fairly rudimentary in function: some can only make out light and shadow, others some minimal detail.
The two primary eyes (called Anterior Medial eyes, for those interested) are quite something else, though. One of the best set of eyes in the invertebrate world, the eyes are telescopic in nature, recording an extraordinary amount of detail. The eyes also have four different kinds of receptor cells, giving them the ability to perceive four distinct colours (humans, in comparison, have only three different types,) giving them a visible range stretching from near UV to the near IR spectrum.
The apparent curiosity of theirs comes in because of this: their tiny little brains take a second or more to process all the incredibly rich visual information that comes their way, so they often stay still in that time.
The usual experience of a photographer with a jumping spider (that’s not too jumpy) usually goes like this: You approach the spider; the spider “takes cognizance” of you and quickly turns to look at you; the doe eyes stay focused on you for a few seconds; if you move or go closer, the spider usually jumps backwards while continuing to face you; you click some more pictures.
That may not sound like much in print, but that’s pretty awesome for a photographer. ^_^