Vertebrate Zoology: A Tutorial - T. A. Dauda 2014

Multicellular Animals
Class Aves
Superorder Paleognathae, or Ratites — Order Rheiformes, or Rheas

Rheas are native to the grassland regions of South America. They are smaller than African ostriches, typically standing about 1.5 m tall and weighing around 30 kg. Their plumage is brownish-gray, they have three toes on each FOOT, and their wings are relatively well-developed. They live in flocks of several dozen individuals. During the breeding season, they break into smaller groups consisting of a single male and 5–7 females, all of which are fertilized by the male—a classic example of polygamy. The females lay their eggs in a communal nest, which typically contains between 15 and 40 eggs. Only the male incubates the eggs and tends to the chicks afterward. Rheas are farmed under semi-domesticated conditions.



Last update: 13/08/2026

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