Elephant ancestry? The remarkable case of the rock hyrax

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‘Seriously?’ This – or similar – is the standard response when guides inform guests that a rock hyrax’s closest relative is the elephant. Are they even looking at the same animal? 

Binoculars are raised for a closer scrutiny of the rotund, furry little creatures clustered atop the boulder. Elephants? Perhaps they’re bigger than they look but just further away. Perhaps their trunks are tucked away out of sight. But no, that first impression was correct: these animals are roughly the size, shape and general demeanour of a large guinea pig.

So, what’s with the jumbo story? Well, to be strictly accurate, scientists now believe that the closest relatives of elephants are the sirenians (manatees and dugongs). But the guide is in the right ball park. The three groups – elephants, hyraxes and sirenians – have all diverged in their very different ways from one prehistoric African ancestor. Today they are more closely related to each other than they are to anything else.

It just goes to show how, in evolutionary terms, you should never judge a book by its cover. Yes, hyraxes – also known as dassies – may resemble rodents. But look closer at their anatomy and you’ll find key differences: incisor teeth that protrude as small tusks; stumpy toes with hoof-like nails; hidden testes (in the male) that are tucked up in the abdominal cavity; and teats (in the female) that are located close to the armpits. All these features are shared with elephants.

The fossil record sheds more light. It turns out that during the Eocene Epoch (56–33.9 million years ago) hyraxes were Africa’s dominant herbivores, with a wide variety of species that ranged from mouse-sized to as big as a horse. What we see today, therefore, does not paint the full hyrax picture.

But your binoculars cannot look into a hyrax’s prehistoric past any more than they can into its molecular biology. So what are you looking for when you see one today?

Well, the rock hyrax (Procavia capensis) is the largest of four extant species, weighing up to 4kg and about the size of a small, short-tailed house cat. Its close relative, the yellow-spotted bush hyrax, is slightly smaller but equally widespread. Both live in small colonies among isolated rock outcrops, either in hilly areas or in flat savannah.

Scan these outcrops from a distance and you may well spot one or two lounging on the sun-warmed boulders. Hyraxes sunbathe regularly to assist their thermoregulation and spend more than 90 per cent of their time lounging around. The rest is spent feeding on vegetation, growing on or around their rocky home. They will often climb into nearby trees to nibble the juiciest leaves – though should not be confused with tree hyraxes, which live entirely in forests and are largely nocturnal.

Get closer, and your binoculars should be able to make out the pointed nose, short tail and flat toes. You might also spy the dorsal crest – an erectile patch of white fur along the spine that serves for scent marking.

Too close, though, and the hyraxes will probably scarper, showing remarkable agility among the rocks and crevices, special sweat glands on the rubbery soles of their feet allowing extra traction. These animals live in perpetual fear of their number one predator, the Verreaux’s eagle, and they don’t take chances. In some tourist areas, however, they can become very tame. Indeed, hyraxes make excellent pets – Joy Adamson having been one famous, and doting, owner.

So don’t scoff next time you hear the elephant story. Show hyraxes some respect. After all, perhaps these intriguing little mammals – just like their larger relatives – never forget.

(Image: Mike Unwin)

To get the best out of your wildlife or safari experience, Travel Africa encourages the use of a good quality binocular. To further enhance the experience and capture great memories, take an iPhone adapter to connect your iPhone to your binocular.

This column is sponsored by Swarovski Optik, the premier range of optics for wildlife in glorious close-up. To see their full range visit www.swarovskioptik.com

Mike Unwin is an award-winning travel writer and author who has an insatiable fascination with wildlife and animal behaviour. 

READ MORE: See all of Mike Unwin’s Seeing is Believing articles here: https://travelafricamag.com/category/blogs/mike-unwins-seeing-is-believing/

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