The Common Raven (Corvus corax), also known as the Northern Raven, is a large, all-black passerine bird. Found across the northern hemisphere, it is the most widely distributed of all corvids. There are at least eight subspecies with little variation in appearance— although recent research has demonstrated significant genetic differences among populations from various regions. It is one of the two largest corvids, alongside the Thick-billed Raven, and is possibly the heaviest passerine bird; at maturity, the Common Raven averages 63 cm (25 inches) in length and 1.2 kg (2.6 pounds). 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 and in some areas has been so numerous that it is considered a pest. 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, cereal grains, berries, fruit, small animals, and food waste.
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 indigenous cultures, including those of Scandinavia, ancient Ireland and Wales, Bhutan, the northwest coast of North America, and Siberia and northeast Asia, the Common Raven has been revered as a spiritual figure or god.