If you don’t live anywhere near Australia or New Zealand, there’s a high chance you will never see this spider in the course of your lifetime. These large spiders are incredibly venomous, but normally use this venom to stun their prey, before restraining it with its silk, and then taking it back to its web. Most of the time, these spiders stay away from humans, but they have been known to bite – with disastrous consequences. A red back spider bite can render a human completely overcome with latrodectism. A human will experience vomiting, muscle cramping, sweating and swelling.