![]() ![]() And that’s a big advantage for a small animal that is both hunter and prey. Taken together, the eight eyes offer a nearly 360-degree view of the world. They let the spider watch what’s happening behind it. On each side of the spider’s head is another pair of lower-resolution eyes. They’re on the lookout for things that might need the attention of those bigger, high-resolution eyes. This pair scans a wide field of view, but only in black and white. Beside each of these eyes is a smaller, less sharp eye. Together they form an “X” of high-resolution color vision. Each of those two principal eyes sees only a narrow, boomerang-shaped strip of the world. That sharp vision, however, covers only a small portion of the spiders’ field of view. “In terms of size-for-size,” she says, “there’s just no comparison whatsoever to the type of spatial acuity that jumping-spider eyes can achieve.” Nelson studies jumping spiders at the University of Canterbury. “Given that you can fit a lot of spiders in one single human eyeball, that is pretty remarkable,” says Ximena Nelson. The big, front-facing principal eyes have the highest resolution known for such a small animal. When they work together, these eyes offer nearly a 360-degree view of the world. The eight eyes of a jumping spider, here seen magnified from above with a scanning electron microscope. In fact, human vision is only about five to 10 times better than a jumping spider’s. Their sight is comparable to that of much larger animals, such as pigeons, cats and elephants. It’s also the secret to their stalking and pouncing on prey with impressive precision. Yet their eyesight is sharper than that of any other spider. The jumping spiders’ two forward-facing primary eyes have incredibly high resolution for creatures whose entire bodies usually span a mere 2 to 20 millimeters (0.08 to 0.8 inch). Each of these spiders’ eyes has a single lens that focuses light onto a retina. ![]() Like other spiders, its camera-type eyes more closely resemble those in humans and most other vertebrates. They merge information from their hundreds or thousands of lenses into a single mosaic image. Seeing the world from a spider’s viewīees and flies have compound eyes. ![]() He’s a visual ecologist at the University of Cincinnati in Ohio. “Part of why I study insects and spiders is this act of imagination that is required to really try to get into the completely alien world … and perceptual reality of these animals,” says Nathan Morehouse. Through innovative experiments, researchers have been teasing out how these spiders see, feel and taste their environment. Lately, scientists have been discovering there’s much more to these tiny arachnids than they had once realized. But these spiders are best known for their hilariously flamboyant mating dances and their itty-bitty size. Indeed, some are smaller than a sesame seed. Their two large front eyes make for adorable close-ups. Their family includes more than 6,000 known species. Explainer: Insects, arachnids and other arthropods High-definition color appears only wherever you point a small spotlight. ![]() It’s a bit like watching a poorly focused black-and-white movie on a 3-D IMAX screen that wraps around the room. It’s one small window of sharp, colorful detail in an otherwise gauzy gray world. At the center of this X, all is crisp and clear. But this view extends so far around to the sides that you can even make out dim shapes and motion behind you no need to turn your head! The only color you see falls within a bright, X-shaped splash that moves with your gaze. Imagine seeing the world largely in shades of gray - and a little blurry, too. ![]()
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