Dolphin Genome Yields Evolutionary Insights
It seems that being a brainiac is just in a dolphin’s genes. That’s the upshot from a paper, published on 27 June in the Proceedings of the Royal Society B, that contains insights from the recently sequenced genome of the bottlenose dolphin (Tursiops truncatus). Researchers say that the results should shed light on the evolution of the dolphin nervous system and reveals commonalities with other large-brained mammals.
“Dolphins are a really interesting model to look at because so much of their morphology is modified,” says Mike McGowen, a postdoctoral fellow in molecular genetics at Wayne State University (WSU) College of Medicine in Detroit, Michigan, and a co-author on the study.
Last fall, a team led by researchers at Baylor College of Medicine in Houston, Texas, took the first crack at sequencing the bottlenose dolphin’s genome, as part of a larger study of several mammalian genomes. Although the resulting sequence has gaps, the WSU team used it to flag some 10,025 genes with counterparts in the genomes of nine other mammals, including cows, horses, dogs, humans and elephants. They found 228 gene sequences that had changed significantly relative to other mammals. About 10% of those relate to the nervous system — a probable driver of the dolphin’s mental prowess.
“It was something we were hoping to find, since studies have shown that they have a large brain and high cognitive ability,” says McGowen.