A male peacock displaying its open tail

Sexual dimorphism

Sexual dimorphism describes animals where there is a physical differences between males and females of the same species (other than in the sex organs). One may be significantly larger than the other, colouration may be different or one might have additional body parts such as antlers, ornate plumage or a mane. In the rarer cases where females are larger or more ornate it is termed reverse sexual dimorphism.

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Animals with this behaviour

Mammals

Birds

Reptiles

Amphibians

Insects

Crabs, shrimp and krill

Behaviours

Other Morphology behaviours

BBC News about Sexual dimorphism