Spiders are among the most diverse, widespread and successful predators in the animal kingdom, due in part to the versatile powers at their disposal; their feet can scale any surface, their fangs pack corrosive venom and they secrete a highly adhesive substance more powerful than steel. You might think there isn’t much else a spider needs to survive, but many spiders exhibit even more unusual specialization.
Interestingly enough, there are hundreds of spider species – most of them jumping spiders – that closely resemble ants. Yes, that is a spider in the above image. Some of these arachnids use this disguise to hunt insects that are unafraid of ants, or protect themselves from predators that prefer to eat spiders. Others, of course, may prey upon the ants themselves, like wolves in sheep’s clothing.
Spiders can end up with a lot of junk hanging in their webs with them, so they might as well put it to use. Some species will bundle up silk, old prey remains and detritus into clumps around the same size, shape and color as themselves, creating a row of “false” spiders they can hide amongst. This is useful to confuse flying predators such as dragonflies, robber flies or small birds who may attempt to swoop by and pluck a tasty spider from its web.
Celaenia excavata is not the only spider to imitate disguise itself as a wad of bird excrement, but it certainly sports the most convincing disguise. Not only is the spider’s body colored exactly like bird poo (complete with a seed-like spot!) but it sits atop a highly convincing “splatter” fashioned from its own silk. It’s the perfect disguise for a spider, since it’s highly unappetizing to spider-eating animals but looks enticingly tasty if you happen to be, say, a fly.
Most spiders are aggressively solitary, treating even their own species as just an edible invader in their territory. A few species, however, are highly social and may build tremendous, complex web systems shared by thousands of individuals. One such spider is Eduador’s Theridion nigroannulatum – these spiders hang upside-down in large groups, dangling hundreds of silk strands to the ground. When a large insect brushes by these tripwires, dozens of spiders may drop down together and wrap it in silk.
Newly hatched or very small spiders can often travel thousands of miles by a process called “ballooning.” A special kind of silk called “gossamer” is produced that easily catches on the wind, and forms into a triangular parachute that may remain airborne for weeks at a time, even allowing spiders to colonize distant islands.
The “ogre faced” or “net casting” spiders of order Deinopidae hang upside down from just a few strands of silk, holding an unusuall small, dense web between their front legs they use to physically reach out and scoop up passing insects. The silk of this special net isn’t sticky, but so fuzzy that it instantly entangles the hairs and joints of insects like velcro, allowing the spider to trap fairly large and powerful insects with only a small amount of silk.
Many garden spiders construct webs with a distinct pattern of thick silk at the center, the purpose of which was long debated. We now know that this special silk is reflective to UV light, creating patterns similar to those used by flowers to attract their insect pollinators.
The bizarre “bolas spiders” or Mastophorea use their silk in a manner unlike any other arachnid group, secreting a dense, round glob of glue on the end of a single long “fishing line”…complete with lure. Each species of bolas spider emits a pheromone attractive to the males of a different moth species, who come looking for a lady-moth only to get whacked in the face by the spider’s goo-ball.
Argyroneta aquatica is one of the only true spiders that can be found completely underwater, earning it the name “diving bell spider.” Its hairy abdomen can trap a thin layer of air around its breathing pores, which it carries back and forth between the surface and its underwater web. The web is structured to trap a large pocket of air – just like a man-made diving bell – where the female raises her young and consumes her prey.
10. Ant Mimicry
Interestingly enough, there are hundreds of spider species – most of them jumping spiders – that closely resemble ants. Yes, that is a spider in the above image. Some of these arachnids use this disguise to hunt insects that are unafraid of ants, or protect themselves from predators that prefer to eat spiders. Others, of course, may prey upon the ants themselves, like wolves in sheep’s clothing.
9. Dummy Spiders
Spiders can end up with a lot of junk hanging in their webs with them, so they might as well put it to use. Some species will bundle up silk, old prey remains and detritus into clumps around the same size, shape and color as themselves, creating a row of “false” spiders they can hide amongst. This is useful to confuse flying predators such as dragonflies, robber flies or small birds who may attempt to swoop by and pluck a tasty spider from its web.
8. Fake poop
Celaenia excavata is not the only spider to imitate disguise itself as a wad of bird excrement, but it certainly sports the most convincing disguise. Not only is the spider’s body colored exactly like bird poo (complete with a seed-like spot!) but it sits atop a highly convincing “splatter” fashioned from its own silk. It’s the perfect disguise for a spider, since it’s highly unappetizing to spider-eating animals but looks enticingly tasty if you happen to be, say, a fly.
7. Colonial super-webs
Most spiders are aggressively solitary, treating even their own species as just an edible invader in their territory. A few species, however, are highly social and may build tremendous, complex web systems shared by thousands of individuals. One such spider is Eduador’s Theridion nigroannulatum – these spiders hang upside-down in large groups, dangling hundreds of silk strands to the ground. When a large insect brushes by these tripwires, dozens of spiders may drop down together and wrap it in silk.
6. Hang-gliders
Newly hatched or very small spiders can often travel thousands of miles by a process called “ballooning.” A special kind of silk called “gossamer” is produced that easily catches on the wind, and forms into a triangular parachute that may remain airborne for weeks at a time, even allowing spiders to colonize distant islands.
5. Handheld mini-webs
The “ogre faced” or “net casting” spiders of order Deinopidae hang upside down from just a few strands of silk, holding an unusuall small, dense web between their front legs they use to physically reach out and scoop up passing insects. The silk of this special net isn’t sticky, but so fuzzy that it instantly entangles the hairs and joints of insects like velcro, allowing the spider to trap fairly large and powerful insects with only a small amount of silk.
4. False advertising
Many garden spiders construct webs with a distinct pattern of thick silk at the center, the purpose of which was long debated. We now know that this special silk is reflective to UV light, creating patterns similar to those used by flowers to attract their insect pollinators.
3. Fatal attraction
The bizarre “bolas spiders” or Mastophorea use their silk in a manner unlike any other arachnid group, secreting a dense, round glob of glue on the end of a single long “fishing line”…complete with lure. Each species of bolas spider emits a pheromone attractive to the males of a different moth species, who come looking for a lady-moth only to get whacked in the face by the spider’s goo-ball.
2. Scuba tanks
Argyroneta aquatica is one of the only true spiders that can be found completely underwater, earning it the name “diving bell spider.” Its hairy abdomen can trap a thin layer of air around its breathing pores, which it carries back and forth between the surface and its underwater web. The web is structured to trap a large pocket of air – just like a man-made diving bell – where the female raises her young and consumes her prey.
1. Web Shooters
Nearly all spiders produce silk from organs called spinnerets on the tip of the abdomen, and need to be able to touch something to wrap it up in webbing. Not so for the genus Scytodes, the “spitting” spiders, who have additional silk glands connected to their mouthparts. Slowly creeping up on unsuspecting insects, the spitting spider squirts twin streams of silk that are even laced with its own venom, waving its streams back and forth to lasso prey in a criss-crossed toxic net.
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