Tarantulas are a type of arachnids belonging to the family Theraphosidae. They are invertebrates with an exoskeleton. Their body is divided in two parts: prosoma (cephalothorax) and opisthosoma (abdomen). There are about 900 species of tarantulas, all of them venomous (but not dangerous for humans) and silk producers. They eat arthropods and the biggest tarantulas can also feed of lizards, mice, and birds. As they can't chew, they just suck, after they grab a prey, they inject the venom to paralyse it and then they pour digestive acids on it. The size of tarantulas depends on the specie; its body can be from 2.5 cm up to 10cm and males are bigger than females.