rhea (redirected from Rheas)

rhea, in zoology

rhea (rē`ə), common name for a South American bird of the family Rheidae, which is related to the ostrich. Weighing from 44 to 55 lb (20–25 kg) and standing up to 60 in. (152 cm) tall, the rhea is slightly smaller than the ostrich and lacks that bird's extravagant plumelike tail feathers. The rhea also differs from the unrelated ostrich in structure of the palate, pelvis, and foot. It is yellow and gray above, with a black head and dirty-white underside. The greater, or common, rhea (Rhea americana) is found from northeastern Brazil to Argentina. The somewhat smaller lesser, or Darwin's, rhea (Pterocnemia pennata) occurs from Patagonia to the high Andes. The rhea is typically a creature of the pampas and savannas and may often be found feeding in mixed herds along with cattle or guanaco, occupying an ecological niche similar to that of the ostrich and the zebra of Africa. Rheas feed on several kinds of plants, insects, and small vertebrates. While the old males tend to stay solitary, the young male is aggressive and highly polygamous, gathering about itself from three to seven hens. The nest is built in a dry and protected area, preferably near water. The male excavates a shallow hole with his bill, lines it with dry vegetable matter, and assumes all the incubation duties. He may incubate as many as 50 eggs, produced by a number of females over a period of weeks. Incubation takes from 35 to 40 days. The eggs, lemon yellow when laid, or greenish in the case of Darwin's rhea, weigh up to 2 lb (almost 1 kg) each. When hatched, the chicks are gray with darker stripes. The rhea is one of the flat-breastboned, or ratite, flightless birds. Rheas are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Struthioniformes, family Rheidae.

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Rhea, in astronomy

Rhea, in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn V (or S5), Rhea is 950 mi (1530 km) in diameter, orbits Saturn at a mean distance of 327,487 mi (527,040 km), and has equal orbital and rotational periods of 4.517 earth days. The second largest of Saturn's moons, Rhea was discovered by the Italian-French astronomer Gian Domenico Cassini in 1672. Rhea's density of 1.3 means that it is composed primarily of water ice, rocky material making up about a third of its mass. Its leading hemisphere is highly reflective and heavily cratered, strongly resembling the cratered highlands of the moon, although Rhea's craters do not have high walls or a towering central peak; the trailing hemisphere is darker with bright wispy streaks and few impact craters.

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Rhea, in Greek religion and mythology

Rhea, in Greek religion and mythology, a Titan. She was the wife and sister of Kronos, by whom she bore Zeus, Poseidon, Pluto, Hestia, Hera, and Demeter. She eventually helped Zeus overthrow Kronos. Her worship, which was orgiastic and associated with fertility rites, was particularly prominent in Crete. The Greeks often identified her with Gaea and Cybele. In Rome, Rhea was worshiped as Magna Mater and identified with Ops. See Great Mother Goddess.

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rhea

Either of two ostrich-like species of South American three-toed ratite birds (family Rheidae). The common rhea (Rhea americana) is about 4 ft (120 cm) tall and weighs about 50 lbs (20 kg). It has luxuriant plumage, brown or gray above and whitish below. Darwin's rhea (Pterocnemia pennata) is smaller and has white-tipped brownish plumage. Rheas live in open country, often among grazing animals, and run from predators. They eat a wide variety of plants and animals. Both species are listed as endangered.

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Rhea

Greek goddess, one of the Titans. Daughter of Uranus and Gaea, she married her brother Cronus, who swallowed all their children except Zeus, whom Rhea concealed. Zeus then overcame Cronus and restored his siblings.

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rhea

either of two large fast-running flightless birds, Rhea americana or Pterocnemia pennata, inhabiting the open plains of S South America: order Rheiformes (see ratite). They are similar to but smaller than the ostrich, having three-toed feet and a completely feathered body

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rhea [′rē·ə]

(botany)

ramie

(vertebrate zoology)

The common name for members of the avian order Rheiformes.

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Rhea [′rē·ə]

(astronomy)

A satellite of Saturn, with estimated diameter of 450 miles (1530 kilometers).

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Rhea

worshiped orgy and fertility; mother of Zeus, Poseidon, Hera, Hades, Demeter, and Hestia. [Gk. Myth.: NCE, 1796]

See : Fertility

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Rhea

often titled Great Mother of the Gods. [Gk. Myth.: NCE, 1796]

See : Motherhood