The Sphenisciformes order of birds is a particularly distinct, homogeneous one, comprising a single family, Spheniscidae, the penguins.
The distribution of these birds is limited to the Southern Hemisphere.
One species of the eighteen in this order, the Galapagos penguin, lives at the equator, and a few species inhabit temperate regions, but the majority breed on islands in subantarctic waters.
Total populations of most species run into the millions and some are noticeably increasing, apparently due to sharp reductions in the numbers of Antarctic whales, which complete with penguins for the krill that form the basis of both animals' diets.
Most species of penguins lay two eggs, though the emperor and king penguins lay only one, and incubation is performed by the male and female parent alternately, once the female has returned form some two weeks at sea, where she feeds and recovers from the effort of egg-laying.
Here, too, the emperor penguin proves to be an exception to the rule, for the female usually has to walk from 50 to 100 miles to the sea and then walk the same distance back again, by which time incubation is complete.
The Sphenisciformes order of birds is a particularly distinct, homogeneous one, comprising a single family, Spheniscidae, the penguins. The distribution of these birds is limited to the Southern Hemisphere. One species of the eighteen in this order, the Galapagos penguin, lives at the equator, and a few species inhabit temperate regions, but the majority breed on islands in subantarctic waters. Total populations of most species run into the millions and some are noticeably increasing, apparently due to sharp reductions in the numbers of Antarctic whales, which complete with penguins for the krill that form the basis of both animals' diets. Most species of penguins lay two eggs, though the emperor and king penguins lay only one, and incubation is performed by the male and female parent alternately, once the female has returned form some two weeks at sea, where she feeds and recovers from the effort of egg-laying. Here, too, the emperor penguin proves to be an exception to the rule, for the female usually has to walk from 50 to 100 miles to the sea and then walk the same distance back again, by which time incubation is complete.
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