Welcome to the Birds Portal! Birds
) are bipedal
, oviparous vertebrate animals
. Most scientists believe that birds evolved
from theropod dinosaurs
. Ranging in size from tiny hummingbirds
to the huge ostrich
, there are between 9,000 and 10,000 known living bird species in the world, making Aves
the most diverse class of terrestrial vertebrate
A bird is characterized by feathers, a toothless beak, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a light but strong skeleton. All birds have forelimbs modified as wings and most can fly.
Birds are important sources of food, acquired either through farming or hunting. Numerous species of birds are also used commercially, and some species, particularly songbirds and parrots, are popular pets. Birds figure prominently in all aspects of human culture from religion to poetry and popular music. Numerous species of birds are threatened with extinction by human activities and as a result efforts are underway to protect them.
The term flight feather
refers to any of the long, stiff, asymmetrical feathers
on the wing
of a bird
; those on the wing are called remiges
(singular remex) while those on the tail are called rectrices
(singular rectrix). Their primary function is to aid in the generation of both thrust
, thereby enabling flight
. However, the flight feathers of some birds have evolved to perform additional functions, generally associated with territorial displays, courtship rituals or feeding methods. In some species, these feathers have developed into long showy plumes used in visual courtship displays, while in others they create a sound during display flights. Tiny serrations on the leading edge of their remiges help owls
to fly silently (and therefore hunt more successfully), while the extra-stiff rectrices of woodpeckers
help them to brace against tree trunks as they hammer. Even flightless birds still retain flight feathers, though sometimes in radically modified forms.
The moult of their flight feathers can cause serious problems for birds, as it can impair their ability to fly. Different species have evolved different strategies for coping with this, ranging from dropping all their flight feathers at once (and thus becoming flightless for some relatively short period of time) to extending the moult over a period of several years.
||A traveler without observation is a bird without wings.
Free online resources:
There is also Birds of North America, Cornell University's massive project collecting information on every breeding bird in the ABA area. It is available for US$40 a year.
For more sources, including printed sources, see WikiProject Birds.
The common raven
), also known as the northern raven
, is a large all-black passerine bird
in the crow family
. Found across the northern hemisphere
, it is the most widely distributed of all corvids
. There are eight known subspecies
. It is one of the two largest corvids, and is possibly the heaviest passerine bird. common ravens typically live about 10 to 15 years in the wild, although lifespans of up to 40 years have been recorded. Young birds may travel in flocks, but later mate for life, with each mated pair defending a territory. The common raven has coexisted with humans for thousands of years. Part of its success comes from its omnivorous
diet; common ravens are extremely versatile and opportunistic in finding sources of nutrition, feeding on carrion
, insects and food waste, in addition to cereal grains, berries, fruit and small animals. Some remarkable feats of problem-solving have been observed in the species, leading to the belief that it is highly intelligent
. Over the centuries, it has been the subject of mythology, folklore, art and literature in many cultures.
Collaboration of the month
Every month a different bird-related topic, article, stub or non-existent article is picked. Please improve the article any way you can.
|Class Aves, divided into superorders, orders, suborders (where indicated), and families.
The following Wikimedia
sister projects provide more on this subject: