Observation of Galápagos bramblings
showed that human food influences a shape of a beak of birds that promotes formation of new types in the nature, influences natural selection and can change the course of evolution of birds.
Experts from the University of the State of Massachusetts in Boston (USA) watched birds on Galapagos Islands.In the nineteenth century, the Galapagos finches inspired Charles Darwin's famous work on evolution.Their general ancestor arrived to Galápagos about two million years ago, and since then on islands there were more than ten recognized species of bramblings who differ by the body size, a shape of a beak and behavior.
Scientists decided to find out whether bramblings show interest in human food and as it can be reflected in their life. For eggs they placed forages (natural seeds), natural to birds, and also rice, cookies and chips in trays. To define flavoring preferences of birds, the forage from each cell was weighed before and after an experiment.
As it appeared, bramblings in the city area eat almost exclusively human food. The birds living far from human houses ignored trays with similar food. An urbanization led to the fact that birds essentially changed a diet. On the island Santa Cruz it already led to the fact that for the last 40–50 years differences in a shape of a beak at two species of bramblings disappeared.