Another creationist myth has bitten the dust, although that's unlikely to stop it being repeated. A new species emerged under the eyes of biologists able to study it closely, and it happened faster than anyone expected. Appropriately, the species is a Galapagos finch, one of the subfamilies crucial to Darwin's world-changing revelation.
The diversity of the Galapagos Islands has created multiple niches for finches, leading them to evolve different-shaped beaks and varying body sizes in order to take advantage of the variety of food sources available. Yet even Darwin himself doubted evolution would happen fast enough for us to detect it in real time. “We see nothing of these slow changes in progress, until the hand of time has marked the lapse of ages,” he wrote.
Bacteria evolve so fast that microbiologists can indeed bear witness to the appearance of new species, but vertebrate zoologists are seldom so lucky. So when the famous finch trackers Drs Peter and Rosemary Grant of Princeton University noticed something new on the island of Daphne Major, they were deeply hesitant to claim what they were seeing was more than just a variety of an existing species.
Other scientists were more audacious, and three years ago the suggestion that the Grants had potentially described a new species as it appeared reached the wider community. Now the Grants have published a paper announcing what they once described as “highly unlikely”; the appearance of a self-contained population in just two generations as the result of the arrival of a single stray bird on Daphne Major. Moreover, the events appear to be even more surprising than previously suspected.
The story began in 1981 when an unusually large male with a distinctive beak arrived on Daphne Major. "We didn't see him fly in from over the sea, but we noticed him shortly after he arrived. He was so different from the other birds that we knew he did not hatch from an egg on Daphne Major," Peter Grant said in a statement. Initially thought to be a hybrid of two other species from a nearby island, genetic sequencing has now shown the new arrival was a Geospiza conirostris from Española island, 100 kilometers (60 miles) away.