Cats are very susceptible to black widow venom as are horses but dogs are relatively resistant, and sheep and rabbits are apparently immune. While there are only a few spiders in the United States that are really dangerous to humans, there are significant numbers around the world. The black widow and recluse spiders have very toxic venom that can be life threatening to humans. Pigeon spiders of West Africa give very painful bites. There are four main methods that spiders use to capture prey.
Sedentary spiders living in silk-lined burrows leap out to capture passing insects.
Some spiders, like hunters, go in search of their prey. Many spiders spin webs to entrap their prey. All spiders are carnivorous, Most spiders eat insects but a few of the larger species are big enough to prey on small vertebrate animals like mice or small birds. Most spiders' jaws work from side to side. They have toothed edges used in breaking up the prey during feeding.