Evolution in Action

For the first time a case of evolution in progress has been observed.   This amazing event has been discovered, and it is making waves across the globe.   In Lake Victoria, Africa’s largest lake, and one of the largest fresh water bodies in the world, a fish has evolved into two distinct species.   A species of fish belonging to the “Cichlid Family” has been observed as having split into to different and unique species.

 The unexpected aspect of this is that the two species that have evolved were not separated geographically.   Geographic separation was thought to be a necessary driving force in the evolution of species.   In this case however, there was no geographic separation.   The two species are living in the same body of water.   This divergence is the result of ever increasing pollution and the results of changes in climate. The original species had been forced to adapt the way that its vision functions.   This eventually led to a new and separate species. Observations regarding cichlids in Lake Victoria make provisions for evidence of an unusual form of evolution called ‘sympatric specification’ that takes place without a population group’s physical separation.

The ‘Pundamilia Nyererei’ is native to the regions in the MWanza Gulf area of Lake Victoria.   This area is comprised of several islands and in each region the fish are varied by color.   In a report published by the journal “Nature”, researchers from a technological institute in Tokyo along with researchers from the ‘Swiss Federal Institute of Aquatic Science and Technology’ have observed the Cichlid evolving into an entirely new species that has never been seen before.   This new species is adapted to the changes in light at various depths of the lake.  

Scientists have also stated that it isn’t simply over-fishing and pollution alone that are responsible for the disappearance of certain fish species in Lake Victoria.   And it is not these factors alone that are the cause of the evolution of the other species. The report goes on to summarize that new and different species might be born due to vision differences as well as the things seen by the fish, at least in regard to this particular lake in Africa.  In fact, the latter reason proves to be the driving force which caused the fish to evolve into a novel species.

 The above-mentioned phenomenon might explain the rapid losses relating to pundamilia in Lake Victoria over the last 30 years. Studies have said that eye adaptations also affect mating patterns. Researchers had a look at 2 different species, each being conspicuous due to their blue or red colors. They went on to determine via lab experiments that some genetic mutations aided certain fish which live in greater depths.   The mutation made a pigment in their eyes that is more sensitive with respect to red light, whereas shallow-water fish are more sensitive to blue light.

 Scientists have stated the theory of evolution as being ‘survival of the fittest’. In a way, they are right. Amongst the fish in the lakes of Africa only the fittest survive.   Where they are not fit, they change.