Their arms are so flexible that they resemble a snake’s tail, which gives these animals their name (from the Greek «ophis,» meaning snake, and «ura,» meaning tail). They are so fragile that when disturbed, one of their arms is likely to detach or break into small pieces, but this is not a big problem for the little starfish as it can regenerate it in a short time.
Snake stars are usually very abundant, and the family is divided into 1,600 different species. Among them, Ophiactis savignyi (in the photo) has a particular form of reproduction. This tiny starfish reproduces through transverse fission, where its body, originally equipped with six arms, splits into two small starfish, each with three arms. Each part can regenerate the missing arms, but only two of them will regenerate, resulting in two starfish with five arms.
From that point on, they can only reproduce sexually, giving birth to offspring with six arms that can in turn split to restart the process. Initially, it was believed that savignyi starfish, like other starfish, split in order to escape from predators. However, today it is suspected that this fission is also related to balancing the populations of males and females in a particular area.
Evidence of this occurrence could be that in areas where there is a greater abundance of females, they split less, while males split more, thus achieving the stabilization of male and female populations to ensure reproduction. The success of this strange reproductive method is demonstrated by the fact that these small starfish are truly abundant in all the world’s seas, from the Arctic to the Antarctic.
Perhaps, as humans, we find it incredible to understand that an animal can clone itself, dividing into two identical animals to double a specific population. It may be unbelievable to us that a small and fragile animal like the snake starfish can exhibit such behaviors, or even not being able to understand how they know if what is lacking in the territory is males or females.
It may be incredible for our human minds, but the sea is a place where anything can happen. A place where there are no animals that are not astonishing and surprising. It’s just a matter of knowing how to search there, at the bottom, beneath the rocks, and then be amazed.
«One cannot defend what one does not love, and one cannot love what one does not know.»