It’s been very clear since Darwin said it. Evolution is the process by which species mutate according to their environment. Or your needs. The popular idea is that this process takes thousands of years. Is it really like that? How fast does evolution happen? According to a recent analysis, species can evolve in a few hundred years. The team of evolutionary biologist Axel Meyer (University of Konstanz) published the study in Nature.
Data was collected from crater lakes in Nicaragua. Meyer has been studying genomes since 1980. Here he analyzed very young species of cichlid fish. Often a few hundred generations. They have multiple phenotypes in the same crater lake. There are fish with pronounced lips and without lips, fish of gold color and black and white … These phenotypes have their origin in the crater lakes. That is, in the same geographical area, without external barriers such as rivers or mountains.
They do not represent new mutations that arise independently of one another. But the sorting and selective selection of the same original genetic variants that have been rearranged in individual lakes.
Ernst Mayr is known to his contemporaries as “Darwin of the 20th century”. It helped develop the concept of biological species. For him this would be an indication that it is a separate species. However, the new results from genome sequencing suggest otherwise.
More genes, more species
It was therefore found that the combined effect of many genes has a stronger influence on the development of new species. The geographic location makes the investigated crater lakes a “natural experiment”. The original fish populations come from two much older, unrelated, neighboring lakes. This chain of crater lakes was colonized independently of fish populations.
When and how did specimens of the original population get into the smaller lakes? It can only be calculated by simulation. But it was a few hundred and a few thousand generations ago. There weren’t many fish populating the crater lakes.
Therefore, as shown in this study, the emergence of new species can occur much faster than previously thought. Meyer compares the lakes with the Petri dishes, which were all inoculated with the same genetic starting point. They develop independently of one another over generations: “There are very few systems like this in the world. The Galapagos Islands or the crater lakes in Nicaragua are a natural experiment for evolutionary research. It helps us understand how fast evolution happens.