Lots of lizards have fun spiny appendages. It’s part of what makes lizards so interesting. But did you know there’s an entire genus of lizards known for their big, spiny tails? The name of the genus is Uromastyx, which means ‘tail whip’ or ‘tail scourge’.
There are currently thirteen species in the genus, all of which are found in Northern Africa and the Middle East. They live in areas that have places to burrow and hide, which usually means rocky habitats. In addition to rocks, spiny-tailed lizards also prefer warm and dry climes, and so live in deserts and semi-arid environments.
Spiny-tailed lizards are medium to large sized lizards, with the smallest species reaching lengths of 25 cm and the largest getting to be almost a meter long. Colouration varies within species, from reddish to orange, green, yellow or grey. Even within an individual lizard, colours will change depending on the temperature. In cooler weather the lizards become darker, to more effectively absorb the sun’s warmth.
The great big tails that are so characteristic of spiny-tailed lizards are mainly used for defence. The lizards’ main method of avoiding predators is to flee into the safety of their burrows. If this fails they will swing their tails at their attacker, so unless you want to get clubbed with a big spiny tail, leave these guys alone.
Spiny-tailed lizards can also be aggressive, particularly against members of their own species who are foolhardy enough to venture into one another’s territory. Females are especially nasty during the breeding season. In North African spiny-tailed lizards, the only way males can approach females to mate is by shaking their heads from side to side and doing lots of push-ups.
Females lay between five to 40 eggs, which hatch in around 80 days. The females guard their nests until the eggs hatch, and from then on the young are on their own. The young lizards are a boring grey or brown colour at brith, and only gain full adult colouring around four years of age. Full size is reached when the lizards are eight or nine years old.
Spiny-tailed lizards aren’t just cool because of their tails. Living in desert environments requires some nifty adaptations to conserve water. Hiding in their burrows is a behavioural adaptation that allows spiny-tailed lizards to maintain a reasonably constant body temperature even on exceptionally hot days. North African spiny-tailed lizards eat a lot of plants that are high in salt, which is a problem, because excreting salt also means getting rid of water. The lizards get around this by having glands in their nostrils that can eliminate salt without water loss.
I feel like if you live in the desert, you have to be tough. And if you’re tough, you should probably have spines somewhere on your body. Therefore, it is only logical to conclude that spiny-tailed lizards are the perfect desert dwellers. QED.