A jay is a member of a number of species of medium-sized, usually colorful and noisy, passerine birds in the crow family, Corvidae. The evolutionary relationships between the jays and the magpies are rather complex. For example, the Eurasian magpie seems more closely related to the Eurasian jay than to the East Asian blue and green magpies, whereas the blue jay is not closely related to either. The Eurasian jay distributes oak acorns, contributing to the growth of oak woodlands over time. Systematics and species. Jays are not a monophyletic group.
https://en.wikipedia.org/wiki/Jay