Fish evolved super fast into two species in the same lake

Swiss scientists have discovered that the three-spiny species quickly evolved into two distinct distinct species of genetics, even though living in the same area for 150 years.

According to New Scientist, the barramundi is taken to Lake Constance in Switzerland about 150 years ago. Since then, this fish quickly evolved into two distinct types : one that lives in the main lake and one that lives in streams flowing into the lake .

The fish that live in the main lake are larger, have long spines and harder scales. In theory, these differences may be due to lifestyle and not evolution. Lake fish live longer, so they are more likely to grow.

On the left is a three-spine fish that lives in the main lake (the female is above, the male is below).On the right is a three-spine fish living in the stream.(Photo: New Scientist).

However, scientists at the University of Bern, Switzerland discovered that there is a clear genetic difference between the two species."We can consider the beginning of these two species," said Dr. David Marques at the University of Bern.

Especially, both types of fish breed in the same stream at the same time of the year. They have been bred long ago, and continue to breed, but divided into two genetically and physically different species.

According to Dr. Chris Bird of the University of Texas, USA, an expert in the study of organism development according to genetic analysis, this is the formation of a distributed regional species, once considered very unlikely. The formation of this species almost always requires separate populations of habitable areas to avoid mutual mating.

When mating animals, the process of recombining the genetic variants takes place, the genes of the mother and the father are mixed together in the next generation. As long as individuals within groups continue to mate, it is unlikely that two groups with marked genetic characteristics will appear.

Marques' group found genetic differences between the two types of fish focusing on chromosomes that are less likely to recombine. As a result, gene variants that make up their unique characteristics are less likely to be divided.Lake Constance sticklebacks may continue to grow until they become two species that do not mate.