Corvidae is a cosmopolitan family of oscine passerine birds that contains the crows, ravens, rooks, magpies, jackdaws, jays, treepies, choughs, and nutcrackers.

[5] Specifically, members of the family have demonstrated self-awareness in mirror tests (Eurasian magpies) and tool-making ability (e.g. crows and rooks[6]), skills which until recently were thought to be possessed only by humans and a few other higher mammals.

Their total brain-to-body mass ratio is equal to that of non-human great apes and cetaceans, and only slightly lower than that of humans.

The name Corvidae for the family was introduced by the English zoologist William Elford Leach in a guide to the contents of the British Museum published in 1820.

The presumed corvid relatives included: currawongs, birds of paradise, whipbirds, quail-thrushes, whistlers, monarch flycatchers and drongos, shrikes, vireos, and vangas,[2] but current research favors the theory that this grouping is partly artificial.

The corvids constitute the core group of the Corvoidea, together with their closest relatives (the birds of paradise, Australian mud-nesters, and shrikes).

The crested jayshrike (Platylophus galericulatus) is traditionally included in the Corvidae, but is not a true member of this family, being closer to the helmetshrikes (Malaconotidae) or shrikes (Laniidae).

[14] The following tree showing the phylogeny of the crow family is based on a molecular study by Jenna McCullough and collaborators published in 2023.

However, Steller's jays, which are successful independently of human development, are more efficient in plundering small birds' nests than American crows and common ravens.

Therefore, the human relationship with crows and ravens did not significantly increase nest predation when compared to other factors, such as habitat destruction.

Youngsters of social corvid species undergo a series of tests, including aerobatic feats, before being accepted as a mate by the opposite sex.

[19] The natural diet of many corvid species is omnivorous, consisting of invertebrates, nestlings, small mammals, berries, fruits, seeds, and carrion.

[19] Some corvids will eat carrion, and since they lack a specialized beak for tearing into flesh, they must wait until animals are opened, whether by other predators or as roadkill.

When compared to dogs and cats in an experiment testing the ability to seek out food according to three-dimensional clues, corvids out-performed the mammals.

Tate et al. (2006) explored the issue of non-human mammals processing the visual cues from faces to achieve interspecific communication with humans.

[42] Researchers also examined the avian species' capabilities to interpret this non-verbal communication, and their extent of sensitivity to human emotions.

To test these two hypotheses, McCune et al. (2018) performed an experiment on the boldness of two species in Corvidae: the Mexican Jay and California Scrub-Jay.

[49] A study published in 2008 suggested that the Eurasian magpie is the only non-mammal species known to be able to recognize itself in a mirror test,[50] but later research could not replicate this finding.

Magpies have been observed taking part in elaborate grieving rituals, which have been likened to human funerals, including laying grass wreaths.

[54] Marc Bekoff, at the University of Colorado, argues that it shows that they are capable of feeling complex emotions, including grief.

Recent studies revealed abilities to solve complicated problems, which suggested high levels of innovation of a complex nature.

Researchers have discovered that New Caledonian crows do not just use single objects as tools—they can also construct novel compound tools through assemblage of otherwise non-functional elements.

[19] Contrary to earlier teleological classifications, in which they were seen as "highest" songbirds due to their intelligence, current systematics might place corvids—based on their total number of physical characteristics, instead of just their brains (which are the most developed of birds)—in the lower middle of the passerine evolutionary tree, dependent on which subgroup is chosen as the most derived.

Humans have been able to coexist with many members of the Corvidae family throughout history, most notably crows and ravens (see: "Role in myth and culture" section below).

[71] Due to their carrion diet, the Celtic peoples strongly associated corvids with war, death, and the battlefield; their great intelligence meant that they were often considered messengers, or manifestations of the gods, such as Bendigeidfran (Welsh for "Blessed Crow") or the Irish Morrigan (Middle Irish for "Great Queen"),[72] both who were underworld deities that may be related to the later Arthurian Fisher King.

In many parts of Britain, gatherings of crows, or more often magpies, are counted using the divination rhyme: "one for sorrow, two for joy, three for a girl, four for a boy, five for silver, six for gold, seven for a secret never to be told."

On a shield and purse lid excavated among the Sutton Hoo treasures, imagery of stylised corvids with scrolled beaks are meticulously detailed in the decorative enamel work.

The corvid symbolism reflected their common totemic status to the Anglo-Saxons, whose pre-Christian indigenous beliefs were of the same origin as that of the aforementioned Vikings.

The children's book Mrs. Frisby and the Rats of NIMH and its animated film adaptation features a protagonist crow named Jeremy.

For example, the destruction of the Southeast Asian rainforest is endangering mixed-species feeding flocks with members from the family Corvidae.