Ever wake up in the morning and just ask yourself, "Why"? This volunteer science writer does not profess to have all the answers to that question by any means but, I do think that one of them is the possibility of someday meeting such animals as those I write about and others that you only dream of. For this week, we aspire to meet the pangolins.
There are only eight extant species of pangolin (most of which are endangered), four in Asia and four in Africa. While not actually related to anteaters, they are also called scaly anteaters because, similar to anteaters, they are edentate (lack teeth) with long tongues (up to 16 inches in larger species) and have strong, thick claws used to burrow for insects such as ants and termites.
They produce a special sticky mucous from salivary glands on the tongue to help catch and trap wily insects. Where to put this grossly elongated tongue you ask? Well, it retracts right down into the abdominal cavity near the pelvis! Without teeth to chew up ant-y food, the pangolins have developed a gizzard-like stomach (as seen in birds), ingesting small stones and sand to help grind their meals once inside the stomach. They have excellent hearing but do not have external ears, and they have a well-developed sense of smell.
Several species are arboreal, some live in burrows and almost all species are nocturnal. Many arboreal species, such as the tree pangolin (M. tricuspis), have strong prehensile tails which they use when climbing. The giant pangolin (Manis gigantea) of Africa can grow to five feet in length and is too large to climb trees.
These crazy mammals are most notable for their complete covering of overlapping, armored scales made of keratin, that same material responsible for human fingernails. If threatened, pangolins roll up into a tight ball with the head tucked under the tail. They have well developed muscles which makes them very hard to pry apart and the outer edge of the scales are very sharp, so you would not be wise to attempt to unroll an upset pangolin. If that isn't convincing enough, they also have anal scent glands that produce a noxious odour, similar to our North American friends, the skunks (but again, no relation).
Pangolins are secretive and solitary and not much is known about their reproduction, but they are placental (eutherian) mammals, as are humans, and give birth to between one and three young at a time (most give birth to just one but it depends on the species). Young are born with soft scales that take a couple of days to harden. Young survive by hanging on to the mothers tail or back, or remaining in the burrow for several weeks, depending on the species. If danger approaches the mother will tuck up the baby under her belly as she rolls up, protecting them both.
The first pangolins known in the fossil record are from the Eocene period, about 50 million years ago. For comparison, the first recognizable Homo sapiens showed up about 200 000 years ago.
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