How Does it Move and get food
Amongst the vast numbers of invertebrate animals in the Phylum Arthopoda, more than a million different kinds have bodies with three main parts--head, thorax, and abdomen. The head has eyes, antennae and mouthparts. The thorax has three pairs of legs. The entire body is protected by a tough outer covering called an exoskeleton. Animals that share these characteristics are called insects. The group to which they belong is called the Insecta
http://www.explorit.org/science/spider.html
http://www.explorit.org/science/spider.html
Whatever their hunting strategy, the vast majority of spiders follow the same basic killing and feeding procedure. The spider's primary weapon is its chelicerae, a pair of jointed jaws in front of the mouth. Each jaw has two major parts: the basal segment, the bulk of the jaw, and the sharp fang housed inside of it.
Normally, the fang is retracted inside the basal segment. When the spider catches its prey, it swings the fangs out into the animal's body. The fangs work something like hypodermic needles. They have a small hole in the tip and a hollow duct inside. The duct leads to the venom gland, either inside the basal segment or farther back in the cephalothorax. When the spider pierces its prey with the fang, it squeezes out the venom, injecting the animal with enough neurotoxin to paralyze or kill. This makes it safe for the spider to feed on its prey, without the risk of a struggle. In the mygalomorph spider suborder, which includes the various tarantulas, the chelicerae are positioned so that the fangs swing forward into the prey, like an axe. In the dominant araneomorph suborder, the chelicerae swing in toward each other, like a pincer. For the mygalomorph system to work effectively, the prey has to be on ground or another solid surface -- the spider has to sandwich the prey between something else and the fangs. The araneomorph system works whether or not the prey is on solid ground -- the chelicerae simply push against each other. |
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Love 'em or hate 'em, you've got to admit that spiders are some pretty impressive, well-equipped animals. They have a top-notch sensor array, a built-in construction set, a heavily armored body and a highly effective venom-injection system. How many other creatures can claim that?
These remarkable adaptations have made spiders some of the most successful carnivores in history. In their 400 million years of existence, they've spread over every continent and mastered nearly every environment on Earth. Today, there are about 40,000 known spider species, and potentially thousands more we haven't discovered yet. This is pretty astounding when you consider that there are only about 4,000 different species in the entir
Love 'em or hate 'em, you've got to admit that spiders are some pretty impressive, well-equipped animals. They have a top-notch sensor array, a built-in construction set, a heavily armored body and a highly effective venom-injection system. How many other creatures can claim that?
These remarkable adaptations have made spiders some of the most successful carnivores in history. In their 400 million years of existence, they've spread over every continent and mastered nearly every environment on Earth. Today, there are about 40,000 known spider species, and potentially thousands more we haven't discovered yet. This is pretty astounding when you consider that there are only about 4,000 different species in the entire mammal kingdom.e mammal kingdom.http://animals.howstuffworks.com/arachnids/spider.htm
These remarkable adaptations have made spiders some of the most successful carnivores in history. In their 400 million years of existence, they've spread over every continent and mastered nearly every environment on Earth. Today, there are about 40,000 known spider species, and potentially thousands more we haven't discovered yet. This is pretty astounding when you consider that there are only about 4,000 different species in the entir
Love 'em or hate 'em, you've got to admit that spiders are some pretty impressive, well-equipped animals. They have a top-notch sensor array, a built-in construction set, a heavily armored body and a highly effective venom-injection system. How many other creatures can claim that?
These remarkable adaptations have made spiders some of the most successful carnivores in history. In their 400 million years of existence, they've spread over every continent and mastered nearly every environment on Earth. Today, there are about 40,000 known spider species, and potentially thousands more we haven't discovered yet. This is pretty astounding when you consider that there are only about 4,000 different species in the entire mammal kingdom.e mammal kingdom.http://animals.howstuffworks.com/arachnids/spider.htm