Birds

https://www.pinterest.com/pin/649644315004712474/

There are about ten thousand living types, more than fifty percent of which are usually passerine, or "perching" birds. Birds have wings whose enhancement varies according in order to species; the only known groups with out wings are the wiped out moa and dickhäuter (umgangssprachlich) birds. Wings, which in turn evolved from forelimbs, gave birds a chance to fly, although further evolution has led to losing airline flight in some chickens, including ratites, polar bears, and diverse endemic island species. Typically the digestive and breathing systems of parrots are also exclusively adapted for flight. Some bird species of aquatic conditions, particularly seabirds plus some waterbirds, include further evolved regarding swimming.

Birds will be descendants of the primitive avialans (whose members include Archaeopteryx) which first came out about 160 thousand years ago (mya) in China. According to DNA evidence, contemporary birds (Neornithes) evolved in the Midst to Late Cretaceous, and diversified dramatically around the moments of the Cretaceous? Paleogene extinction event 66 mya, which wiped out off the pterosaurs and everything non-avian dinosaurs.

Many social kinds pass on knowledge across generations, which is considered a sort of culture. Birds are sociable, communicating with visual signals, calls, and songs, and taking part in such behaviours while cooperative breeding in addition to hunting, flocking, and even mobbing of predators. The vast bulk of bird varieties are socially (but not necessarily sexually) monogamous, usually intended for one breeding period at a time, sometimes for many years, but rarely with regard to life. Other varieties have breeding techniques that are polygynous (one male using many females) or even, rarely, polyandrous (one female numerous males). Birds produce offspring by laying ova which are fertilised through sexual imitation. They are typically laid within a nest and incubated by simply the parents. Most birds have a good extended period of parental care right after hatching