They hunt using sensory organs on their legs to detect the vibrations of moving prey. Tarantulas inject their venom using fangs located on their chelicerea. Their venom pre-digests their prey allowing them to drink their meal with their mouth parts. Tarantula venom is not lethal to humans, but allergic reactions may cause life-threatening problems. Tarantulas utilize their venom as a secondary line of defense against predators.
Many species possess urtricating hairs that work like porcupine quills to be thrown at predators.
The term urtricating means irritating or inflaming. Like other spiders, a cuticle or exoskeleton covers tarantulas. The fine hairs all over the body are called setae. Tarantulas are mygalomorph spiders whose fangs are used to strike downward and pull the prey against the body. Tarantulas extend their legs using blood pressure rather than muscles.