Brood Hierarchy
The Blue-footed Booby brood of two chicks always has a dominance hierarchy due to the asynchronous hatching of the eggs. One egg is laid four days before the other, and incubation starts immediately after laying, so the elder chick is hatched four days before the younger chick and has a four-day head start on growth. The elder, stronger chick almost always becomes the dominant chick. During times of food shortage, the dominant chick often kills the subordinate chick by either repeatedly pecking or by ousting the younger chick from the nest. The brood hierarchy makes it easier for the subordinate chick to die quietly in times of food scarcity, which provides an efficient system for booby parents to maximize their investment.
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Famous quotes containing the words brood and/or hierarchy:
“One of the saddest sights of the slums is to see the thrifty wife of the working man, with her rosy brood of children, used to country air and sunshine, used to space, privacy, good surroundings, cleanliness, quiet, shut up amid the noise and dirt and confusion, in the gloom of the slum.”
—Albion Fellows Bacon (1865–1933)
“In a hierarchy every employee tends to rise to his level of incompetence.”
—Laurence J. Peter (1919–1990)