Learning Scala

Colophon

The animal on the cover of Learning Scala is the American Ostrich, or the greater rhea (Rhea americana), a tall, flightless bird found in eastern South America. Known locally as the ñandú, it is one of the two birds that comprise the rhea species, along with its smaller, more uncommon counterpart, the lesser rhea (rhea pennata).

Endemic to Argentina, Bolivia, Brazil, Paraguay, and Uruguay, the greater rhea inhabits open areas with tall vegetation, such as grasslands, savanna, and grassy wetlands. Curiously, a small nonindigenous population also exists in rural northwest Germany, established in 2000 after several escaped from a farm. These birds have prospered in the wild, defying all expectations.

While markedly similar to the African ostrich, the greater rhea has three toes rather than two and is about half the size; adult rheas stand at about five feet tall and weigh between 44 and 60 pounds. Its fluffy plumage is gray, with dark patches on the crown, neck, and upper back. The bird’s long, powerful legs make it a fast runner, capable of reaching speeds of over 35 miles per hour. Its large wings, which help maintain balance while running, are also flaunted in elaborate courtship displays.

The American Ostrich typically nests near water. Rheas are polygamous, and so each male may mate with up to twelve females during the spring and summer, its breeding season. Males become extremely territorial during this period, behaving aggressively toward one another. After mating, ...