Birds are a very diverse group of animals, and this is epitomized best by the staggering array of beaks they possess. The thin, dainty beaks of hummingbirds (family Trochilidae), for example, contrast strongly with the hooked shell-cracking beaks of the macaws (family Psittacidae), or the long, probing bills of the killdeer (Gallinago sp.). The adaptations of each species' beak speaks volumes about the birds' diet, lifestyle and habitat.
Birds with stout, conical beaks are able to generate great force -- perfect for eating seeds. Though modified, conical beaks allow for more flexibility than some more highly derived beaks do; many seed-eating birds also incorporate berries and insects in their diets. Purple finches (Haemorhous purpureus) are especially clever at maximizing their conical beaks; they will access the nectar of flowers by biting the flower off at the base. Seeds that can't be swallowed by a tufted titmouse (Baeolophus bicolor) are taken to a perch where the enterprising bird will repeatedly smash the seed with his stout beak. Because of this seed-based diet, many birds with conical beaks, like purple finches or northern cardinals (Cardinalis cardinalis) are commonly seen at backyard bird feeders.
Hawks, owls and other birds of prey have strongly hooked beaks. As these predators often capture animals larger than they can swallow, they use their beaks to rip prey into manageable sized pieces. Often, this large prey fights back, and could even cause injury to the raptor. To combat this, falcons (family Falconidae) have sharp projections on their upper mandibles, termed tomial teeth. These tooth-like structures help the birds to break the spine of their prey quickly and effectively.
Pointed, Thin Beaks
Birds with pointed, thin beaks usually eat insects or worms, though they may also consume fruits. The familiar American robin (Turdus migratorius) uses his long beak to probe for worms in the soil. Other insect-eating species with a long, thin beak include the brown creeper (Certhia americana). This small bird features a very thin, curved beak. These birds systematically search the deep furrows in the trunks of large trees, and capture any insects they find with their beaks.
Woodpeckers (family Picidae) have sturdy, pointed beaks that allow them to chisel into wood and bark. Woodpeckers pound on trees to find hidden insects, excavate nests and advertise their presence via a series of loud knocks. Their well-adapted beaks serve all of these purposes well, and have allowed the woodpeckers to become a very successful lineage. Though the beaks of woodpeckers are good at making holes in the wood and bark of a tree, the beaks aren't especially helpful for extracting an insect from the hole. To deal with this, some species have very long, sticky-tipped tongues that can fish out the insect. The tongue is extremely long in the case of the red-bellied woodpecker (Melanerpes carolinus), extending to three times the length of the bill.
- The Cornell Lab of Ornithology: Northern Cardinal
- The Cornell Lab of Ornithology: Purple Finch
- The Cornell Lab of Ornithology: Tufted Titmouse
- SeaWorld: Birds of Prey
- Delaware Valley Raptor Center: Raptor Adaptations
- The Cornell Lab of Ornithology: American Robin
- The Cornell Lab of Ornithology: Brown Creeper
- Nebraska Bird Partnership: Adaptations