Songbirds could play role in conservation
A species of songbirds can gradually evolve into two that have distinct songs and colour variations without ever interbreeding, says a University of British Columbia biologist whose work would make Darwin swoon. Darren Irwin used a new genetic analysis technique to show that the greenish warbler native to forests in Asia changes characteristics as its population spreads across the Tibetan Plateau. Eventually, it becomes another species altogether. "No one's ever shown such a nice, gradual change between two clearly separate species before," said Irwin, associate professor in UBC's zoology department.