The word
incubate in the context of
birds refers to the development of the chick (embryo)
within the
egg and the constant temperature required for the
development of it over a specific period. This in most
species of bird is produced by body heat from the brooding
parent, though several groups, notably the Megapodes,
instead use geothermal heat or the heat generated from
rotting vegetable material, effectively a giant compost
heap. The Namaqua Sandgrouse of 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.
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 Swan and 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 Plover incubates 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 Albatross and the Brown Kiwi). In these latter,
the incubation is interrupted; the longest uninterrupted
period is 64 to 67 days in the Emperor Penguin.[1]
Some species begin incubation with the first egg, causing
the young to hatch at different times; others begin after
laying the last egg of the clutch, causing the young to
hatch simultaneously.
Derived meanings
Climate-controlled incubators are used in industrial
agricultural settings and in neonatal care, especially of
human infants. The life expectancy for premature infants has
increased dramatically thanks to
incubation.
In economics, a
business incubator is an organization providing physical
space, communications tools, investments or human resources
intended to support the development of a new firm.
Approximate egg-development time, post-hatch of a regular,
avian creature is six days for full flight capability in
males; twelve in females.
Reference
Christopher Perrins (editor), Firefly Encyclopedia of
Birds,
ISBN 1-55297-777-3