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Very often, turtles, crocodiles, chameleons and other snakes are not particularly praised for their intelligence. It has long been thought that these animals lead solitary lives, that they are slow-moving, and that they ultimately turn out to be either dangerous or uninteresting. It didn’t take much more to classify them among the betas… While not at all! We now realize that we were wrong. Today, I invite you to discover a lizard, which defies all predictions.
Skinks belong to one of the largest families of lizards known to date, with more than 1,000 different species! All skinks are easily recognized by their rather stocky silhouette: they often have a very short or even absent neck and very small legs. But, today, I suggest you take an interest in a species of skink in particular: Egernia stokesius. It has no vernacular name in French, that is to say it has no common name. It is referred to only by its Latin name, but to make things easier, let’s call it “Stokes skink”.
This little lizard takes its Latin name from John Lort Stokes, an English admiral who traveled with Charles Darwin during his trip to Oceania aboard the ship The Beagle. Our skink has a few particularities that make it stand out. Brown and beige, chubby and spiny, it has a very thick tail, bristling with pointed scales. This tail, as wide as the rest of its body, is used to store fat for times of scarcity. This kind of prickly club also easily discourages predators who would like to bite into this plump prey! The Stokes skink is one of the giants of its family: it is about 20 centimeters long, about the same size as a rat. It is also old bones, since the oldest known skinks have reached the age of 25 years. Amusingly, young skinks are insectivores and feast on larvae and beetles, while adults are vegetarians and prefer fruits and leaves.
He lives in Australia, very often near a particular tree, a species of acacia that the locals call ” gidgee “. It is he who gives our lizard its most common English common name: Gidgee skink. This surprising tree is sometimes called ” Gidgee stinky”, as it naturally gives off an odor reminiscent of boiled cabbage or sewage. yuck! This fetid environment does not discourage our skink, which is found in all types of environments where it can warm up in the sun, at its ease: semi-desert areas, rocks but also bushes, shrubs and forests. He particularly appreciates the crevices where he arranges a shelter. But then, if we say the scaly rather clumsy, what makes this skink out of the ordinary? To appreciate the real superpowers of the Stokes skink, I suggest you go and see it up close!
The behavior of skinks
Look at this sand and brick-colored landscape, filled with pebbles and rocks. Do you feel that heat, dry, on your skin? This is the perfect place for our lizards. Open your eyes, watch for every crevice. It only takes a little for them to slip into the shade. For them, a crack in a rock is a palace. There, it is inhabited! Let’s put on our skink costume to sneak inside and get a better look at them. There, the two biggest ones at the bottom are the founders of the group, the father and the mother. They remain faithful for several years. And all the other skinks, a little smaller, that can be seen in this crevasse are their babies, which vary in size according to their age. They can stay up to 5 years with their parents, this is the time they need to become adults. Suffice to say that they take their time. And we have already observed very large families, which can include up to 17 individuals! This family organization, where the members of the group stay together throughout the year, is rather rare in the animal world, and all the more so among lizards which often live alone. Most of the time, the latter pair up or gather together for fairly short periods: just enough time to have babies or to spend the bad season in the warmth, tight against each other. But Stokes skinks are community-minded!
If you take a good look at our skinks in this crevasse, you can easily see the benefits of group living. We see them sleeping, stacked against each other. In fact, skinks are poikilothermic, that is to say that their activity depends on the outside temperature. They cannot maintain their body temperature constant, as mammals do, which are homeothermic. If it’s too cold, they don’t have enough energy to move. It’s crazy isn’t it? It’s a bit like getting tired when you go out to play in the snow. By sharing the same crevice, the skinks keep themselves warm, even when the temperature drops suddenly after dark. Together, it’s better than a radiator!
They can also form groups and take turns monitoring the arrival of potential predators, which they spot faster than if they were watching alone. This shared monitoring allows each individual to spend more time napping. Smart! Besides, I think they spotted us. Look, the mother of the group sniffs the air with her tongue. Each time she takes it out, she picks up odors and analyzes them. We humans use our eyes a lot to recognize each other or observe our surroundings. But the skinks do it thanks to the smells! Experiments have shown that they can tell the difference between the scent of a skink of the same species and that of an individual of another species. They can also make the difference between the smell of a male and that of a female and would even be able to recognize congeners individually. Even baby skinks are good at this: they identify their mother for sure, and choose to spend more time near her rather than with other females. This fine use of scents is thought to also allow skinks to find lovers and mates to mate with, as well as to defend their territory by identifying intruders. In short, they have a fine nose. No doubt, the Stokes skink is a surprising animal, which still has many surprises in store for us!