Birds
In birds the cloaca is the terminal chamber of the gastrointestinal and urogenital systems, opening at the vent. Among falconers the word vent is also a verb meaning "to defecate". Excretory systems with analogous purpose in certain invertebrates are also sometimes referred to as "cloacae".
Birds also reproduce with this organ; this is known as a cloacal kiss. Birds that mate using this method touch their cloacae together, in some species for only a few seconds, sufficient time for sperm to be transferred from the male to the female. The reproductive system must be re-engorged prior to the mating season of each species. Such regeneration usually takes about a month. Birds generally produce one batch of eggs per year, but they will produce another if the first is taken away. For some birds, such as ostriches, cassowaries, kiwis, geese, and some species of swans and ducks, the males do not use the cloaca for reproduction but have a phallus. In those, the penis helps ensure that water does not wash away the male's sperm during copulation.
One study has looked into birds that use their cloaca for cooling (see urohidrosis).
Read more about this topic: Cloaca
Famous quotes containing the word birds:
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and come away.
For lo, the winter is past, the rain is over and gone;
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—Bible: Hebrew The Song of Solomon (l. II, 10–12)
“These days of disinheritance, we feast
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The church bells clap one night in the week.
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—Wallace Stevens (1879–1955)
“Alas, so all things now do hold their peace:
Heaven and earth disturbed in no thing:
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The nightes chare the stars about doth bring.”
—Henry Howard, Earl Of Surrey (1517?–1547)