There are birds with long beaks good for picking bugs out of holes, and birds with short thick beaks good for cracking nuts. (religion.blogs.cnn.com)
The team also found that birds with genetic variants for longer beaks were more frequent visitors to the feeders than those birds which did not have that genetic variation. (sciencedaily.com)
In particular, the researchers found that a gene variant, COL4A5 - C, associated with longer beaks in both populations was more abundant in the U.K. birds. (sciencenews.org)