A subspecies of European blackcap birds was noted to have evolved rounder wings and longer, more slender beaks in response to feeding by humans; evolutionary biologists doubted, however, that the birds would ever become a distinct species, because humans are too fickle for animals to depend on in the long term.
A subspecies of European blackcap birds was noted to have evolved rounder wings and longer, more slender beaks in response to feeding by humans; evolutionary biologists doubted, however, that the birds would ever become a distinct species, because humans are too fickle for animals to depend on in the long term.