by Molecular Biology and Evolution (Oxford University Press), February 5, 201 in ScienceDaily
Ever since Darwin first set foot on the Galapagos, evolutionary biologists have long known that the geographic isolation of archipelogos has helped spur the formation of new species.
Now, an international research team led by Theresa Cole at the University of Otago, New Zealand, has found the same holds true for penguins. They have found the first compelling evidence that modern penguin diversity is driven by islands, despite spending the majority of their lives at sea.
“We propose that this diversification pulse was tied to the emergence of islands, which created new opportunities for isolation and speciation,” said Cole.
Over the last 5 million years, during the Miocene period, (particularly within the last 2 million years), island emergence in the Southern Hemisphere has driven several branches on the penguin evolutionary tree, and also drove the more recent influence of human-caused extinctions of two recently extinct penguin species from New Zealand’s Chatham Islands.