David Attenborough presents the crossbill.
Tweet of the Day is a series of fascinating stories about our British birds inspired by their calls and songs.
David Attenborough presents the story of the Crossbill. Crossbills are large finches that specialise in eating conifer seeds. To break into the pine or larch cones, they've evolved powerful bills with crossed tips which help the birds prise off the woody scales of each cone. Crossbills breed very early in the year and incubating birds sometimes have snow on their backs.