- Avian incubation
Incubation is the process by which
birds hatch their eggs, and to the development of the embryowithin the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of sitting on eggs to incubate them is called brooding. The action or behavioral tendency to sit on a clutch of eggs is also called broody, and most egg laying breeds of chickenhave had this behavior selectively bred out of them to increase production.cite book |title=Storey's Illustrated Guide to Poultry Breeds |last=Ekarius |first=Carol |year=2007 |publisher=Storey Publishing |location=210 MAS MoCA Way, North Adams MA 01247 |isbn=978-1-58017-667-5 ]
In most species, body heat from the brooding parent provides the constant temperature, though several groups, notably the
Megapodes, instead use geothermal heat or the heat generated from rotting vegetable material, effectively creating a giant compost heap. The Namaqua Sandgrouseof the deserts of southern Africa, needing to keep its eggs cool during the heat of the day, stands over them drooping its wings to shade them. The humidity is also critical, and if the air is too dry the egg will lose too much water to the atmosphere, which can make hatching difficult or impossible. As incubation proceeds, an egg will normally become lighter, and the air space within the egg will normally become larger, owing to evaporation from the egg.
In the species that incubate, the work is divided differently between the sexes. Possibly the most common pattern is that the female does all the incubation, as in the
Coscoroba Swanand the Indian Robin, or most of it, as is typical of falcons. In some species, such as the Whooping Crane, the male and the female take turns incubating the egg. In others, such as the cassowaries, only the male incubates. The male Mountain Ploverincubates the female's first clutch, but if she lays a second, she incubates it herself. In Hoatzins, some birds (mostly males) help their parents incubate later broods.
Incubation times range from 11 days (some small
passerines and the Black-billed and Yellow-billed Cuckoos) to 85 days (the Wandering Albatrossand the Brown Kiwi). In these latter, the incubation is interrupted; the longest uninterrupted period is 64 to 67 days in the Emperor Penguin. [http://www.birding.com/BirdRecords1.htm] It can be an energetically demanding process, with adult albatrosses losing as much as 83 g of body weight a day. [Warham, J. (1990) "The Petrels - Their Ecology and Breeding Systems" London:Academic Press. ]
Some species begin incubation with the first egg, causing the young to hatch at different times; others begin after laying the second egg, so that the third chick will be smaller and more vulnerable to food shortages. Some start to incubate after the last egg of the clutch, causing the young to hatch simultaneously.
Climate-controlled incubators are utilized in industrial agricultural settings and in neonatal care, especially of human infants. The life expectancy for premature infants has increased dramatically thanks to incubation.
* Christopher Perrins (editor), "Firefly Encyclopedia of Birds", ISBN 1-55297-777-3
Wikimedia Foundation. 2010.
Look at other dictionaries:
Incubation (oiseau) — Pour les articles homonymes, voir Incubation. Couvaison d un serin des Canaries (forme domestique). L incubation ou couvaison des œufs pour les o … Wikipédia en Français
Incubation — The word incubation (from the Latin incubare , to lie upon ) may refer to:* Avian incubation, sitting on or brooding bird s eggs in order to hatch them * Incubation period, a medical term for the time between being exposed to infection and… … Wikipedia
Accouveur — Incubation (oiseau) Pour les articles homonymes, voir Incubation. Couvaison d un Serin des Canaries (forme domestique). L incubation … Wikipédia en Français
Couver — Incubation (oiseau) Pour les articles homonymes, voir Incubation. Couvaison d un Serin des Canaries (forme domestique). L incubation … Wikipédia en Français
Bird nest — For animal nests in general, see Nest. For other uses, see Bird s nest. Deep cup nest of the Great Reed warbler A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a… … Wikipedia
Incubación — Una hembra de azulón incuba sus huevos. La incubación es el acto por el que los animales ovíparos (sobre todo las aves) empollan o incuban los huevos sentándose sobre ellos para mantenerlos calientes y así se puedan desarrollar los embriones. En… … Wikipedia Español
Virginia's Warbler — (female) Conservation status … Wikipedia
Outline of birds — House Sparrow, Passer domesticus The following outline is provided as an overview of and topical guide to birds: Birds (class Aves) – winged, bipedal, endothermic (warm blooded), egg laying, vertebrate animals. There are around 10,000 living… … Wikipedia
Cluck — may refer to Clucking, reproduction related vocal behavior of female chicken Cluck, domestic hen perceived as unproductive of eggs due to brooding phase of avian incubation behavior cluck can transfer to click or other This disambiguation page… … Wikipedia
Bird — For other uses, see Bird (disambiguation). Aves and Avifauna redirect here. For other uses, see Aves (disambiguation) or Avifauna (disambiguation). Birds Temporal range: Late Jurassic–Recent, 150–0 Ma … Wikipedia