NOAA SOUTHWEST FISHERIES SCIENCE CENTER, JOHN DURBAN
Species: Orcinus orca
Genome size: 2.4 billion base pairs
Killer whales, like human populations, have different cultures—behaviors that they learn from their social groups. One behavioral group, or ecotype, might work cooperatively to chase fish into a bait ball, for example, while another might prefer to catch seals, stranding them on ice shelves. To determine the role of behavior in shaping genetics, an international team sequenced 50 genomes of whales from five different cultural groups, including pods that roam the Arctic as well as groups in the Antarctic.
The results, published this spring (May 31) in Nature Communications, suggest that the groups diverged from a common ancestor less than 250,000 years ago and are now evolving independently, despite overlapping geographic ranges. “This is an extremely ...
