For some bird species, the males and females look quite different from one another. The Black-hooded Antshrike (Thamnophilus bridgesi) is a good example. This species is nearly endemic to Costa Rica (also occurring in a part of Panama) and I took these photos of both male and female birds whilst staying at the Bosque del Rio Tigre lodge in Costa Rica. The female, with a lovely streaked head and body, is above. The mostly black male (distinguished by the white spots on his ‘shoulders’) is below.