4020-4023. Hyrax

Hyrax is any species of fairly small, thickset, herbivorous mammals. A hyrax (from Greek ὕραξ "shrewmouse") is any species of fairly small, thickset, herbivorous mammals in the order Hyracoidea. The rock hyrax Procavia capensis, the yellow-spotted rock hyrax Heterohyrax brucei, the western tree hyrax Dendrohyrax dorsalis, and the southern tree hyrax, Dendrohyrax arboreus live in Africa and the Middle East. Hyraxes are well-furred, rotund creatures with short tails. Most measure between 30 and 70 cm long and weigh between 2 and 5 kg. All modern hyraxes are members of the family Procaviidae (the only living family within the Hyracoidea) and are found only in Africa and the Middle East. In the past, however, hyraxes were more diverse, and widespread. The order first appears in the fossil record at a site in the Middle East in the form of Dimaitherium, 37 million years ago. For many millions of years, hyraxes were the primary terrestrial herbivore in Africa, just as odd-toed ungulates were in the Americas. Through the middle to late Eocene, there were many different species, the largest of them about the weight of a small horse, the smallest the size of a mouse. During the Miocene, however, competition from the newly developed bovids—very efficient grazers and browsers—pushed the hyraxes out of the prime territory and into marginal niches. Nevertheless, the order remained widespread, diverse and successful as late as the end of the Pliocene (about two million years ago) with representatives throughout most of Africa, Europe and Asia. The descendants of the giant hyracoids evolved in different ways. Some became smaller, and gave rise to the modern hyrax family. Others appear to have taken to the water (perhaps like the modern capybara), and ultimately gave rise to the elephant family, and perhaps also the sirenians (dugongs and manatees). DNA evidence supports this hypothesis, and the small modern hyraxes share numerous features with elephants, such as toenails, excellent hearing, sensitive pads on their feet, small tusks, good memory, high brain functions compared to other similar mammals, and the shape of some of their bones. Hyraxes are sometimes described as being the closest living relative to the elephant. Although relatively closely related, not all scientists support the proposal that hyraxes are the "closest" living relative of the elephant. Recent morphological and molecular-based classifications reveal the sirenians to be the closest living relatives of elephants, while hyraxes are closely related, but form an outgroup to the assemblage of elephants, sirenians, and extinct orders such as Embrithopoda and Desmostylia. The extinct meridiungulate family Archaeohyracidae, consisting of four genera of notoungulate mammals known from the Paleocene through the Oligocene of South America is a group unrelated to the true hyraxes.