Tourists on Table Mountain may miss the mammalian interest simply because they spend so much time looking at the views that they forget the rocks below their eyeline. On those rocks, often only inches from the edge, are groups of Rock Hyrax (Procavia capensis) doing what hyraxes do best and for a long time—lying in the sun, interrupted only by playful young, itches that have to be scratched and overhead large predators. If South Africans spot them they will immediately call them 'dassies' because that's what they call hyraxes in southern Africa.
Everybody knows that hyraxes are most closely related to elephants but they are fascinating animals for all sorts of reasons. Some features like their feet are obvious.They have sweat glands on the soles such that they are tacky when climbing. The soles of their front feet touch the ground when walking; in other words they are plantigrade. The heels of the hind feet are raised slightly off the ground when walking. This semi-digitigrade condition is one which provides some spring to their step when moving on rocks.
Other features are not so obvious. The generic name, procavia, was derived from cavy (i.e. guinea-pig), early taxonomists considering them some primitive form of the South American rodents. Apart from appearance they do share some characteristics with cavies: a long gestation (very long in the hyrax, 6-7 months); young are mature at birth, able to run around and soon eating solid food. They also have peculiarities during pregnancy. In most mammals, the hormone progesterone increases in concentration in blood as pregnancy progresses; in hyraxes it does not, the blood itself metabolising the hormone into different compounds. Two of my former colleagues did that research in the 1970s. That raises all sorts of questions as to what induces parturition and the onset of lactation in hyraxes.
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