Study Uncovers Genetic Similarities Between Bats and Dolphins
Convergent evolution, or the process through which similar traits evolve in separate species, can be seen throughout the animal kingdom not only on a physical level, but on a genetic one as well, according to a new paper published in the journal Nature.
Led by scientists at Queen Mary University of London, the study is one of the largest genome-wide surveys of its kind and was designed to uncover to what extent convergent evolution of a physical feature, such as echolocation, involves the same genes.
To do this, the scientists used a supercomputer to compare the genomic sequences of 22 animals, including bats and dolphins -- two animals that developed echolocation independent of each other.
Doing so required a sifting through of millions of letters of genetic code using a program designed to calculate the probability of convergent changes developing simply by chance. The results allowed researchers to confidently identify any genes that could be classified as the "odd-man-out."
In all, the scientists discovered nearly 200 different genomic regions concentrated in a variety of "hearing genes."
"We had expected to find identical changes in maybe a dozen or so genes but to see nearly 200 is incredible," Joe Parker from Queen Mary's School of Biological and Chemical Sciences and first author on the paper said in a statement. "We know natural selection is a potent driver of gene sequence evolution, but identifying so many examples where it produces nearly identical results in the genetic sequences of totally unrelated animals is astonishing."
What's more, according to group leader Stephen Rossiter, a Royal Society University research fellow and senior lecturer, the results could represent just "the tip of the iceberg."