Eurasian wren
Wrens are medium-small to very small birds. The Eurasian wren is among the smallest birds in its range, while the smaller species from the Americas are among the smallest passerines in that part of the world. They range in size from the white-bellied wren, which averages under and , to the giant wren, which averages about and weighs almost . The dominating colors of their plumage are generally drab, composed of gray, brown, black, and white, and most species show some barring, especially on the tail or wings. No sexual dimorphism is seen in the plumage of wrens, and little difference exists between young birds and adults. All have fairly long, straight to marginally decurved (downward-curving) bills.