Washington: Scientists have found that there are certain genetic similarities between bats and dolphins and that the evolution of similar traits in different species, a process known as convergent evolution, is widespread not only at the physical level, but also at the genetic level.
The researchers at Queen Mary University of London investigated the genomic basis for echolocation, one of the most well-known examples of convergent evolution to examine the frequency of the process at a genomic level.
The scientists carried out one of the largest genome-wide surveys of its type to discover the extent to which convergent evolution of a physical feature involves the same genes.
They compared genomic sequences of 22 mammals, including the genomes of bats and dolphins, which independently evolved echolocation, and found genetic signatures consistent with convergence in nearly 200 different genomic regions concentrated in several "hearing genes".
The team sifted through millions of letters of genetic code using a computer program developed to calculate the probability of convergent changes occurring by chance, so they could reliably identify `odd-man-out` genes.
Consistent with an involvement in echolocation, signs of convergence among bats and the bottlenose dolphin were seen in many genes previously implicated in hearing or deafness.
The study is published in the journal Nature.