Four pairs are located on a small bump in the middle of the ephalothrax. The main defense tarantulas have against consumption by predators is a patch of loose barbed hairs on the abdomen. When disturbed, they move their hind legs back and forth rapidly over this patch of hairs dislodging them into the air where these hairs may lodge in the eyes or nose of the invader, causing irritation and cessation of the predator's stalk. Sensitive people who come in contact with these hairs may break out in welts. Several people have gotten these hairs lodged in their corneas so care should be taken if one keeps tarantulas as pets.
Tarantulas are the gentle giants of our spider world.
Several species found here in our southwestern desert have a body length of up to about three inches. All species are nocturnal animals, living in holes of their own construction. Tarantulas go to a great deal of trouble to scatter any soil that they remove well away from the entrance. Its hole is about a foot deep, and angles off to the side in a chamber where the tarantula spends most of its time. What isn't immediately obvious is that silk strands extend out from the nest entrance.