Micro-evolutionary bursts of change

Two kinds of killer whale have been found in UK waters, prompting evolutionary biologists to posit that the species of dolphin may be undergoing a speciation event.

The differences are fairly obvious – one kind, dubbed Type 1 had significant adult tooth wear, showing that they feed primarily by sucking up fish into their mouths, while Type 2 showed no wear at all. Type 2, on the other hand, seem to prey on other dolphins and small whales. Type 2 males also seem to be up to two meters larger than Type 1 males.

Evolution in action – an amazing thing.