Desert lizard dances to the beat of the heat

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Vast, intimidating and excessively hot. On the surface, Africa’s Namib Desert seems as though it is virtually desolate. On the surface, this would make sense: The ancient desert is a land of extremes; temperatures can reach as high as 60’C during the day and as low as 0’C at night, and there is precious little water until its scorching dunes reach the salty Atlantic to the West.

Yet, the Namib teems with life. Some 3 500 species of plant thrive in this arid landscape, including the two-leaved Welwitschia, a succulent that can live for over one thousand years. The desert also supports an extraordinary diversity of animal life, all of which have adapted over the millennia to the harsh and unforgiving environment. The Shovel-snouted lizard (Meroles anchietae), named for its flattened snout that ends in a sharp edge, is one such example.

Often found on the Namib’s heated sand dunes, this desert reptile is known to perform a unique thermal “dance” to prevent its feet from burning and its body from overheating: A front leg and opposite hind leg lift on an alternate basis, prompting some to refer to this natural phenomenon as the “Namib quickstep”. Should it get too hot for even its cool moves to handle, the lizard will nose-dive and burrow into the cooler sand or, more sensibly, simply move to the shaded side of the dune. 

One of the driest places on earth (the absolute driest being the Atacama Desert in Chile), some areas in the Namib receive less than 10mm of rain each year. Of course, this is of little bother to Meroles anchietae, because, like most desert wildlife, it has adapted ingenious ways to harvest and preserve. Most of its moisture is gathered by drinking fog from rocks or its body. It also has two bladders, one of which is used exclusively to store water. If full to capacity, the lizard can survive on it for 12 weeks.

Unfortunately, this built-in water canteen makes our shovel-faced friend an extra special treat for Peringuey’s adder, a venomous desert sidewinder who must also do all it can to find and ingest  water to survive.

On a much lighter note, the Shovel-snouted lizard is said to make an excellent pet. If acclimatised while young, the small reptiles are calm and docile around people, preferring to rest on the shoulders of their owners or even hang painlessly from their earlobes. However, many argue that this lizard should be left in its natural habitat, the Namib, where its unique adaptations will always help them beat the heat, deadly sidewinders or not.