Having made its catch, the spider drops off on a silk thread so that it can eat its meal in safety.While the concept of a giant sea spider might sound a little unbelievable, we’re happy (or sorry?) to inform you that it is an absolute reality. The ants are easily caught as they seem to accept the spider as one of them - probably because the spider can mimic the ants' chemical scent signals (chemical mimicry). Bird predators avoid this spider because they see it as a Green Tree Ant, which is a fierce biter and stinger. Looking and behaving like an ant is a useful strategy for many spiders, notably jumping spiders ( Myrmarachne) and the remarkable thomisid spider, Amyciaea albomaculata. Two examples are the Dung Spider ( Phrynarachne decipiens) and the Bird Dropping Spider ( Celaenia kinbergi). The Two-tailed Spiders are also called Rotating Spiders because when prey, such as an ant, comes near, these spiders burst into activity, running rapidly round and round the ant, surrounding it with a barrier carpet of entangling silk bands from the long spinnerets.Īnother example of the superb camouflage that has evolved among the spiders is the number of unrelated spiders that imitate bird droppings on vegetation. The Two-tailed Spider gets its name from its long tail-like spinnerets. Again, this is especially valuable for spiders which are active during the day, like Tama. Other spiders, like the bark-coloured Two-tailed Spider ( Tama) and the leaf-coloured Green Huntsman, simply have colours that blend well into their backgrounds of bark or foliage. Although both of these spiders are very conspicuous on their webs at night, they are well hidden from predators like birds and wasps, which are mostly active by day. Other nocturnal orb weavers, like Poltys, sit on a branch or on bark by day, and look like broken off twig bases or buds. The Wrap-around Spider ( Dolophones sp.), spins its orb web at night, but by day wraps itself around a twig and 'disappears'. Some of these disguises also fool prey animals into approaching close enough to be ambushed. Looking like something you're not, such as a drop of dung or a dangerous or distasteful animal (mimicry), or simply merging into your background (camouflage) has great survival value, especially by day, in avoiding or deterring predators that would otherwise eat the spider. More devious strategies involve camouflage and mimicry. Other strategies include behavioural ploys, like direct threat displays of warning colours on the spider's body, or escaping a predator by dropping quickly away on a silk dragline and playing dead on the ground. Even more amazingly, juvenile spiders can regenerate their legs - a tiny, segmented leg grows within the coxal stump and appears at the next moult. Usually the leg breaks off close to the body, at the coxa-trochanter joint. This is the spider's ability to self-amputate a leg that has been grabbed by a bird or other predator. One of the most amazing of these is called autotomy. Spiders use many strategies to protect themselves from their enemies. Mantispids lay their eggs on bark when the larvae hatch out, they disperse into bark crevices seeking and entering spider egg sacs. Wasps and flies use their long ovipositers to penetrate into the egg sac and lay their eggs among those of the spider. Spider eggs provide a highly nutritious source of food for the larvae of many species of wasps, flies and mantispid lacewings. When the wasp's egg hatches there is plenty of fresh spider food for the hungry larva. They construct cell-like mud nests and pack them with one or several spiders before laying an egg on a paralysed victim and sealing up the mud cell. Mud dauber wasps sting and paralyse spiders, especially small orb weavers. ![]() When the wasp larva hatches, it gradually eats the spider from the outside in, often starting near the spider's waist (pedicel), where the cuticle is softer and it is securely out of reach of the spider legs. ![]() Some wasps lay eggs onto the spider's abdomen. Spiders are often the target of hunting wasps seeking food for their young.
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