Ravens and other members of the corvid family (crows, jays, and magpies) are known to be intelligent. Scientists have discovered that the canny corvids even remember people who give them unfair deals for up to two years.

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Ravens and other members of the corvid family (crows, jays, and magpies) are known to be intelligent. Scientists have discovered that the canny corvids even remember people who give them unfair deals for up to two years.