There are eight species of pangolins worldwide, of which four occur in Asia and four in Africa. Together, the eight species comprise their own Order: Pholidota. Pangolins are unique, as they are the only mammals whose bodies are covered in scales rather than fur. These scales are composed of keratin (the same material that makes up human fingernails), although some species also have a hard layer of calcareous material underneath the keratin. The belly, underside of the head and inside of the limbs are not covered with scales. All pangolins have long, strong claws on their front limbs which are used for digging (and climbing in the arboreal species). The arboreal species (tree pangolins Phataginus spp.) have long, recurved claws on their hind feet and a long, prehensile tail to further assist them when climbing. The two ground pangolin species (Smutsia spp.) have short nails on their hind feet, an adaptation to their terrestrial way of life. They are predominantly solitary and nocturnal, but become active earlier in winter and some individuals may become entirely diurnal during winter. Young animals are also more prone to being active during the day.
All four African pangolins are listed on CITES Appendix I, while also being protected by law in many range states.
Pangolins are entirely myrmecophagous - that is to say they only feed on ants and termites. The proportion of ants and termites consumed varies seasonally and geographically, but typically 90–95% of the diet consists of ants and the remaining 5–10% of termites. Some of the Asian species are believed to feed on other insects as well, but there have been too few studies to verify this. Pangolins are very important natural predators of these insects, keeping their numbers in check. A single pangolin literally consumes millions, if not billions, of ants, termites and their larvae each year. The tongue is very long - as long as the head and body combined - and is thin and covered in sticky saliva. The tongue is retracted into a special sheath called the xiphisternum, which extends along the abdominal wall to the pelvic region and curls upwards and forwards before ending in a blind sac against the diaphragm.
Pangolins have fixed territories which are shared by an adult male and female, as well as the previous year’s offspring. Territory boundaries are presumably demarcated through scent-marking and adjoining territories overlap only marginally. Males have rarely been seen to engage in combat – when in combat, they rise up on their back legs and slash at each other with the long claws on the front limbs. A larger animal may also try to wrap around his smaller opponent and squeeze him.
Pangolins give birth to live young and the females have pectoral mammary glands, like humans and elephants. Females give birth to one baby (which is called a pup) a year and may rarely give birth to twins. Gestation periods are unrecorded and various authors have claimed 3 to 10 months. Pangolins are able to self-implant into the uterus when conditions are favourable. Tree pangolins probably have a gestation period of around three months and Temminck’s ground pangolin has an estimated gestation period of 5 months. It is believed that the ground pangolin species only breed every second year. The pups are born with fully-formed but soft scales, which harden over the first few days. The mother leaves the baby in a burrow (terrestrial species) or hollow tree or log (arboreal species), periodically returning to nurse it. When about one month old, the baby accompanies the mother while she forages. The pup hitches a ride on the base of the mother’s tail, hooking its claws under the mother’s scales. As the pup grows it becomes more adventurous, alternating riding on the mother’s back with foraging nearby. Pups become independent at 3–4 months, but will remain in their natal home range until about one year old.
Pangolins make very few sounds. When they walk or climb, their scales can be heard rubbing against one another and against the vegetation. When awakening or feeding, they snort and chuff audibly. Males also rarely make a soft hooting noise.
Pangolins are long-lived and are believed to live for up to 20 years in the wild, with the oldest recorded pangolin (an Asian species) living for more than 19 years in a zoo. This is the exception, however, as pangolins do not survive well in captivity and most die very soon after entering captivity. This is the reason why there are virtually no pangolins in captivity or in zoo’s worldwide.