Jays are a paraphyletic grouping of passerinebirds within the familyCorvidae. Although the term "jay" carries no taxonomic weight, most or all of the birds referred to as jays share a few similarities: they are small to medium-sized, usually have colorful feathers and are quite noisy. These superificial characteristics set them apart from most other corvids such as crows, ravens, jackdaws, rooks and magpies, which are larger and have darker plumage. Many so-called "jays" are genetically closer to these other corvids than other jays, however.
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