grebe wiki:
>PodicepsTachybaptusPodilymbusAechmophorusPoliocephalusRollandia Grebes are members of the Podicipediformes order, a widely distributed order of freshwater diving birds, some of which visit the sea when migrating and in winter. This order contains on a single family, the Podicipedidae, containing 20 species in 6 genera.Grebes are small to medium-large in size, have lobed toes, and are excellent swimmers and divers. However, they have their feet placed far back on the body, making them quite ungainly on land. They leave the water only to nest, walking very short distances upright like penguins. They can run for a short distance, but often fall over.
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swim wiki:
>This article is about swim, a term for frequency variations. Please see the article on swimming for more information about the water sport and moving through water. Swim is short term variations of the significant instants of a digital signal from their ideal positions. Swim occurs on a longer time scale than jitter but shorter than wander.
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