Bills and Feet Flashcards
Culmen
The upper ridge of a bird’s beak
Knob
Modification of the keratin cover of the bill.
(geese)
Lamellae
Miniature ridges inside the bills of water-feeding ducks (Anatidae) and water birds (e.g. Phoenicopteridae), and serve as filters during feeding.
Maxilla
Nasofrontal hinge
At the forehead, the maxilla bones join the skull at a thin, flexible sheet of nasal bones called the nasofrontal hinge, making the upper bill much more flexile and mobile than it may first appear.
Pterygoid
Supports the maxilla, can slide forward and backward, allowing the upper jaw to extend upward.
Quadrate
Supports the maxilla, can slide forward and backward, allowing the upper jaw to extend upward.
Rhamphotheca
Tough jacket of keratin that forms the visible shape of the bill.
Zygomatic Arch
Digit Numbers
Digital Pads
Resist the wear and tear of walking and perching
Metatarsal Pads
Resist the wear and tear of walking and perching
Digitigrade
Birds are digitigrade, meaning they walk on their toes
Booted
In the booted foot the tarsus is covered by several long, continuous platelike scales, with no small overlapping scales. Booted feet are found in the thrushes.
Scutellate
In the scutellate foot, found in most birds with bare (unfeathered) legs, the tarsus and foot are covered with a tough layer of horny keratin scales called the investment. In most birds, like the Blue Jay, the scales are arranged in an overlapping (imbricated) row along the anterior edges of the tarsus and foot. Scutellate feet are common in songbirds.
Reticulate
In the reticulate foot, the tarsus is covred not by a row of overlapping scales but by a fine patchwork of small, irregularly shapedplates in a reticulated (netlike) patern. Reticulate feet are found in many birds, such as falcons and plovers.
Ansiodactyl
The ansiodactyl foot is the most common arrangement of the avian toe. Songbirds and most other perching birds have ansiodactyl feet.
Zygodactyl
The zygodactyl foot is the 2nd most common toe arrangement in perching birds. It is found in the Osprey, most woodpeckers, owls, cuckoos, most parrots, mousebirds, and some swifts.
Heterodactyl
The heterodactyl foot closely resembles the zygodactyl foot, but in the heterodactyl foot the second toe is reversed, to aid the short, weak first digit in gripping branches. Heterodactyl feet are found only in the trogons.
Syndactyl
In the syndactyl foot, the second and third digits are fused for much of their length. This foot pattern is common in the Order Coraciformes, kingfishers and hornbills.
Pamprodactyl
In the pamprodactyl foot, the first and fourth digits pivot freely forward and backward. Some swifts have pamprodactyl feet. They often rotate all four toes forward and use their tiny feet as hooks to hang while roosting on the walls of chimneys caves, or hollow trees.
Palmate
In the palmate foot, only the anterior digits (2,3,4) are included within the webbing. This is the most common type of webbed foot and is found in ducks, geese, swans, gulls, terns, and other aquatic birds.
Totipalmate
In the totipalmate foot, all four digits are included within the webbing. Totipalmate feet are found in the gannets and boobies, cormorants, and pelicans, all highly aquatic groups.
Semipalmate
Semipalmated means that a small web is present between the anterior digits (2,3,4). Semipalmated feet are found in some sandpipers and plovers, all grouse, and some domestic breeds of chickens.
Lobate
In the lobate foot the anterior digits (2,3,4) are edged with lobes of skin that expand or contract as the bird swims. Lobate feet are found in the grebes, though some palmate-footed ducks have lobes of skin on the hallux.
Raptorial
The raptorial foot is characterized by long, strong digits armed with heavy claws for catching, holding, and killing prey animals. Raptorial feet are found in kites, hawks, eagles, and falcons.
