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Genetics proof Turbo Evolution of Fishes
7.28.09 - Lake Victoria is one of the African Great Lakes. It is 68,800 square kilometers (26,600 sq mi) in size, making it the continent's largest lake, the largest tropical lake in the world, and the second widest fresh water lake in the world. The lake is the habitat for many different species of Haplochromines.
The Great Lakes region of East Africa, including Lake Victoria, is the center of diversity of the mega-diverse cichlid fishes. Paleolimnological evidence indicates dramatic desiccation of this lake approximately 18,000-15,000 years ago. Consequently, the about 500 of extant endemic haplochromine species in the lake must have either evolved since then or refugia must have existed, within that lake basin or elsewhere, from which Lake Victoria was recolonized.

Haplochromis vittatus (Lake Kivu)


Picture by Erwin Schraml



Haplochromis pauciden (Lake Kivu)


Picture by Erwin Schraml



Haplochromis adolphifrederici (Lake Kivu)


Picture by Erwin Schraml



Scientists and Axel Meyer from the University of Konstanz just published a study in the science magazine "Proceedings of the National Academy of Sciences" that shows that the 500 different species all developed within the last 15,000 years which is much faster than scientist had assumed. For an evolution timeframe this is just incredible fast, says Axel Meyer.

Axel Meyer and his colleagues studied the population history of the Lake Victoria region superflock of haplochromine cichlids based on nuclear genetic analysis (12 microsatellite loci from 400 haplochomines) of populations from Lake Kivu, Lake Victoria, and the connected and surrounding rivers and lakes.

Population genetic analyses confirmed that Lake Kivu haplochromines colonized Lake Victoria. Coalescent analyses show a 30- to 50-fold decline in the haplochromine populations of Lake Victoria, Lake Kivu, and the region approximately 18,000-15,000 years ago.

This suggests that it coincides with drastic climatic and geological changes in the late Pleistocene. The most recent common ancestor of the Lake Victoria region haplochromines was estimated to have existed about 4.5 million years ago, which corresponds to the first radiation of cichlids in Lake Tanganyika and the origin of the tribe Haplochrominii. This relatively old evolutionary origin may explain the high levels of polymorphism still found in modern haplochromines. This degree of polymorphism might have acted as a "genetic reservoir" that permitted the explosive radiation of hundreds of haplochromines and their array of contemporary adaptive morphologies.

The result is just stunning to the scientists themselves. Until recently they assumed that even 100,000 years would have been too short of a timeframe to create such an array of different species. Currently the researches can only speculate to why the evolution happened so fast. One theory is that it has to do with the DNAs themselves - i.e. jumping genes.

To learn more about DNAs and Genetics and how they work check out our Genetics and DNA Kit.

Become a Dinosaur Hunter

Become a Dinosaur Hunter Become a Dinosaur Hunter

The Perfect Beginner Experiment Kit!

Stepping into Science

Begin a lifetime of scientific investigation and understanding. Stepping into Science is designed for children 5 & up. It teaches science fundamentals through 25 hands-on science experiments, while at the same time introducing children to the concept and process of experimentation.

The science kit covers five key areas:

  • Nature
  • Physics
  • Chemistry
  • Air
  • Water

The first kit in the Little Labs line - Stepping into Science teaches science fundamentals with step-by-step, hands-on experiments. The kit also includes a booklet with easy to follow instructions.

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Price: only $34.95
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