There are some flocks in Peru that have over a hundred species of birds. – just chance events of whose surviving and who is not, If weak selection, genetic drift can overcome it, All evolutionary processes come into play with geographic variation, Downy woodpecker: latidutinal cline Incubation based on introduced species: The ovaries look very similar to a bunch of grapes. On a kill, for example, only the largest, rarest vultures are actually able to break open the skin of the large mammals. The Nacunda Nightjar in South America makes a corresponding migration between Venezuala and Argentina. There is no evidence that incubation is more costly inside the nest than it is outside the nest. In this case, on each foot two of the toes point forward and the two other toes point backward which makes easy for these birds to climb up and down tree trunks. • Ruby throated hummingbird puts on 2/3’s of its body weight to fly across the Atlantic. They are found worldwide, and their size ranges from 5 cm (bee hummingbird) to 2.75 m (ostrich). In the winters 1969-1971, extra food was provided. (Turns out that sugar water is not good for birds. The earth is on a tilt so that the winter and summer have different amounts of light. For copulation, the male has to get his cloaca close to the tip of the cloaca of a female bird. Dromaeus novaehollandiae (Emu), Southern cassowary (Casuarius casuarius). So, when you release birds by clock-shifting, the Navigation theory says that they should realize this and fly west. • The dorsal elevators are used for fine movements in the raising of the wings. Birds can ‘zip-up’ their feathers by running them the other way and in essence, re-hooking the barbules and barbicels. They lay eggs into the nests of other birds like a crow for incubation and rearing of young. • Optimal diet problem c. The ones up in Alaska, migrate down to Lower California. They have special zygodactylous feet. The body size is either small or very small, which ranges from 2.5–9.1 inches (6.3–23 cm) in length. In a cold place the starlings, bring their ancestral patterns of incubation to it, but the crested myna in cold places does not do so well. Uniformly related individuals (not siblings). In this case, toes are two in fronts, and two behind. Pedro is the low density site. Cotingas of central and south America. Taxonomy: IOC World Bird List (version 10.2). In the study he used chucker partridges and had them run up grades from 0 to 90 degrees. [L. Charadrius = Genus of Plovers + form]. They have a four-chambered heart with two ventricles and two atria. Embryonated chick eggs: Eggs at hatching are usually about 18 days old (ish). Leaping • Classic study showed that the muscle of the supracoracoideus is raised solely by raising the wings. During reproduction, the male provides parental care. Alternatives to the Benefits of Flocking: Small effective pop. Now all the kids are very stressed. This list is on the Web, thanks to the efforts of Rolf A. de By. They inhabit marine and freshwater habitats throughout the world. The food consists of  mouse-birds fruit,  blossoms, seeds, and other types of vegetation. Passerine Birds Its in leks that males can reaches extremes. At present, many birds’ species become endangered due to illegal human activities. Screamers / Anhimidae. This subclass contains about 10,000 known living birds' species throughout the world. These sacs can be so large that they extend into the large bones in the legs. They remember every twist and turn).This hypothesis also does not account for the first flight of young birds. Their palette is much smaller and their ankles have, instead of a process on the astragalus, it’s the calcaneum that has the process. As it turns out, the birds do flock AND there are predators. Anders Molar did a study with Barn Swallows.