The lizard has been seen by everyone - this is a fairly common creature on the territory of Russia, which often goes out in the summer on warm stones and driftwood to bask in the sun. And almost all people in childhood tried to catch such a reptile - but far from everyone managed to. After all, lizards have one rather surprising feature - in a situation when something threatens them, they can easily drop their tail and run away while the catcher is trying to understand what happened. The tail, separated from the reptile, can wriggle for a long time and create deceptive movements.
Why is this happening, and how do lizards manage to drop their tail? Do they grow new, and is it safe for the smallest creature? Answering these questions will not be difficult.
Why does a lizard tail?
A lizard needs a tail, it is a balancer when moving, especially on its hind legs, and a storehouse of reserve nutrients. Tree-climbing lizards use the tail as an extra limb, wrapping branches around it. The existence of a reptile without this part of the body is impossible, because it grows it again if it loses, spending a lot of forces and resources of its body on this process. The process is called regeneration; it is characteristic of reptiles and amphibians. Just as a lizard can grow its tail, a newt can even restore an eyeball or an entire limb - however, it will take him up to six months.
Interesting fact: almost all species of lizards, including large tropical ones, can throw their tail.
Why does a lizard get rid of its tail?
Dropping the tail is not accidental. This part of the body is extremely important, but survival is an even more important task. As a rule, a lizard throws its tail in danger, in situations when something threatens it. A discarded tail can make movements for some time, attracting the attention of a predator, and allowing a small brisk creature to slip away.
A predator can lose sight of its potential prey in these seconds, or be satisfied with a discarded tidbit and leave the lizard alone. It is for these reasons that this mechanism has developed. He justified himself in practice, many lizards were able to save themselves at the cost of a tail, and some of them did this more than once in their lives.
Tail drop - how does this happen?
Regeneration is an amazing process, but no less surprising is how the lizard manages to get rid of the tail in general. After all, the animal does not lose blood, there are no problems with health and well-being either. Hiding from a potential predator, the creature comes out again after a while and behaves exactly as usual. This process was considered by scientists, and it turned out that it really is not traumatic.
Between the vertebrae that separate the tail of the lizard spine, there is no tight connection, the bones in this area are separated from each other. In danger, the back of the reptilian muscle contracts so tightly that the tail simply disengages.The muscles pinch the blood vessels that used to be responsible for feeding the tail, and the lizard runs off without risk of bleeding or pain. For them, this is a completely natural phenomenon, and in science it is called autotomy.
However, it is worth considering that growing a new tail will require a lot of energy. The creature will have to create new fat reserves in it. Losing a tail right before wintering, the reptile risks weakening and even dying in the cold period, since being in suspended animation also requires the use of nutrients accumulated over the summer.
Lizard tail restoration
The tail of the lizard grows slowly, each species has its own time span for this process. Some species cannot restore the tail completely, after loss it grows shorter. Some lizards can grow their tail again only once. And therefore, they discard it only in case of very serious danger, trying to free themselves only from its small area. First, the vertebrae in the growing tail are replaced by cartilage, then it becomes full.
Multi-tailed lizards
Miracles occur in nature. And in particular, some people managed to see a lizard with several tails. This happens if insufficient muscular effort was applied while discarding the tail, the vertebrae were divided, but the tail never fell off. In this case, the old tail remains, but the lizard receives a command to grow a new one.
Today, scientists continue to investigate this feature of lizard behavior despite the fact that it has been studied almost completely as a mechanism. Not so long ago, the presence of special stem cells in geckos was discovered - they are responsible for the regeneration of the spinal cord. It is assumed that the study of these cells will help to cope with the problems of restoration of the spinal cord after injuries in humans.
Thus, dropping the tail is a defensive reaction that manifests itself in lizards when the enemy attacks. The tail distracts the predator, and the reptile usually manages to escape and hide. Then she grows a new tail, because the regenerative processes of her body allow this.
