A new study suggests bats and dolphins developed their echolocation abilities "parallel" to each other.
It's not unheard of for different species' to coincidently develop similar traits, but researchers believe bats and dolphins went through an unusual process of "convergent evolution," ("the evolution of similar genetic sequences ") Nature.com reported.
"These results imply that convergent molecular evolution is much more widespread than previously recognized," molecular phylogeneticist Frédéric Delsuc at the The National Center for Scientific Research (CNRS) at the University of Montpellier in France, who did not participate in the study, told Nature.
Delsuc believes the genes involved in the process are not just the ones involved with the trait in question, but are from a broader genetic category.
The animals use sonar to find their way around, communicate, and hunt for prey. Scientists have long-debated how bats and dolphins developed this interesting trait.
The team analyzed 2,326 genes that were shared by 22 animals and found a "convergence signature' in nearly 200 regions of the genome" Nature reported. Genes involved in hearing and sight were found to have the strongest convergence.
"This study is the first to examine genome-wide convergence at the level of protein sequences and connect it very explicitly to convergent phenotypes, which is very nice," evolutionary biologist Antonis Rokas at Vanderbilt University, said, Nature reported.
Roka believes the suggestion of convergence could mean natural selection really does favor certain genetic sequences.
"It would also help to know how selection influences changes in the types of amino acids within the proteins that the genes code for," Nature reported.
If the convergent amino acids appear much different from the ancestral ones, chances are they were favored by natural selection.
"Radical substitutions [are rarer] because they tend to change the structure and function of proteins quite a bit," Rokas said, according to Nature.
The next step would be to see if any amino-acid changes actually improve an animal's sonar abilities.
