Birds of a Feather Don't Actually Flock Together
According to research done by New Zealand scientists, the old adage that birds of a feather flock together – leading to much inbreeding – has been proved wrong. The journal Nature Communications has studied the migratory behavior and genetics of two populations of Cook's petrel, a small seabird only 200g in weight, that breeds only in New Zealand. It revealed the populations were not interbreeding despite the fact they could easily visit each others' colonies during breeding seasons, said the statement put out by the University of Auckland which commissioned the study.
Because seabirds migrate such large distances, this was found to have contributed to a lack of interbreeding and the presence of very different genetics in the two populations. Until recently, it had been impossible to track many small seabirds at sea over long periods, but the study conducted from 2008 to 2010 used new geolocators lightweight tracking devices attached to the birds' legs and weighing only 2 grams.