Genetics links whale to two different ocean basins | Science Blog:
For the first time ever, a genetic study has followed a single humpback whale from one ocean basin to another, adding to traditional notions of the migratory patterns of these majestic marine mammals in the process, according to researchers from the Wildlife Conservation Society (WCS), the American Museum of Natural History (AMNH), and New York University. In the most recent Royal Society's Biology Letters, a male humpback whale that was first sighted in Madagascar's Antongil Bay in 2000 was found in 2002 swimming off the coast of Loango National Park in Gabon--on the other side of the African continent.
This is gene flow, one of the 4 evolutionary mechanisms, along with genetic drift, mutation, and natural selection. Understanding gene flow in whales improves conservation, and helps us understand how whales have evolved. It's known that there are a number of distinct genetic populations of humpbacks, and how often and by what means they exchange genetic information is crucial to conservation.