A group of scientists from Skoltech and the Institute for Information Transmission Problems of RAS (IITP RAS) showed,
using Lake Baikal amphipods as an example, that parallel evolution driven by adaptations can be detected at the
whole-genome level. The research was published in the Genome Biology and Evolution journal.Illustration by Valentina Burskaia/Skoltech
Similar adaptations are sometimes known to result from exactly the same mutations that occurred independently. The
phenomenon is commonly termed “parallel evolution” to describe evolution that keeps repeating itself. It is usually hard
to prove that such “parallel” mutations did not occur by pure accident but actually help organisms to adapt to their
environment. Thus far, adaptive parallel mutations have been found in some individual genes or small groups of
interrelated genes only.
A team of Skoltech and IITP RAS researchers led by Georgii Bazykin, an evolutionary biologist and a professor at
Skoltech, undertook extensive bioinformatics analysis of protein-coding sequences of 46 amphipod species from Lake
Baikal. The scientists were eager to see whether closely related amphipods from a Baikalian species flock displayed an
elevated rate of adaptive parallel evolution.
The research suggests that adaptive parallel mutations are more common than random parallel mutations in protein-coding
sequences of Lake Baikal amphipods and actually affect several thousand genes. Drawing on the basic laws of molecular
evolution, the scientists showed that the mutations they discovered were indeed caused by the species’ need to adapt to
the environment. However, the exact adaptations behind parallel evolution still remain a mystery.
“Lake Baikal is home to hundreds of species of endemic amphipods that evolved from several species in their distant
ancestry and embrace a variety of ecological niches from predators to planktonic forms and parasites. Parallels were
found even between forms with totally different lifestyles,” says Valentina Burskaia, the first author of the study and
a Skoltech PhD student.