The trumpeters are a family of birds restricted to the humid forests of the Amazon and Guiana Shield in South America. They are named for the trumpeting or cackling threat call of the males. The three species resemble chickens in size; they measure 45 to 52 centimeters long and weigh 1 to 1.5 kg. They are rotund birds with long necks and legs and curved bills and a hunched posture. Their heads are small, but their eyes are relatively large, making them look "good-natured".