গুইসাপ (), and गोह (goh) in Hindi. In West Africa, the nile monitor is known by several names in Yoruba, including , , and . Due to confusion with the large New World lizards of the family Iguanidae, the lizards became known as "goannas" in Australia. Similarly, in South African English, they are referred to as leguaans, or likkewaans, from the Dutch term for the Iguanidae, leguanen. Intelligence Some species of monitors can count; studies feeding rock monitors varying numbers of snails showed that they can distinguish numbers up to six. Nile monitors have been observed to cooperate when foraging; one animal lures the female crocodile away from her nest, while the other opens the nest to feed on the eggs. The decoy then returns to also feed on the eggs. Komodo dragons at the National Zoo in Washington, DC, recognize their keepers and seem to have distinct personalities. Two species of tree monitor in British zoos have been observed shredding leaves, apparently as a form of play. Exploitation As pets Monitor lizards have become a staple in the reptile pet trade. The most commonly kept monitors are the savannah monitor and Ackies dwarf monitor, due to their relatively small size, low cost, and relatively calm dispositions with regular handling. Among others, black-throated monitors, Timor monitors, Asian water monitors, Nile monitors, mangrove monitors, emerald tree monitors, black tree monitors, roughneck monitors, Dumeril's monitors, peach-throated monitors, crocodile monitors, and Argus monitors have been kept in captivity. Traditional medicines Monitor lizards are poached in some South- and Southeast Asian countries as their organs and fat is used in some traditional medicines, although there is no scientific evidence as to their effectiveness. Monitor lizard meat, particularly the tongue and liver, is eaten in parts of India and Malaysia, and is supposed to be an aphrodisiac. In parts of Pakistan and southern India, as well in Northeastern India particularly Assam the different parts of monitor lizards are traditionally used for treating rheumatic pain, skin infections, hemorrhoids, and the oil is used as an aphrodisiac lubricant (sande ka tel). Consuming raw blood and flesh of monitor lizards has been reported to cause eosinophilic meningoencephalitis, as some monitors are hosts for the parasite Angiostrongylus cantonensis. Leather "Large-scale exploitation" of monitor lizards is undertaken for their skins, which are described as being "of considerable utility" in the leather industry. In Papua New Guinea, monitor lizard leather is