Among seabirds named for their big, cornflower-blue feet, adversity early in life doesn't necessarily put kids at a lifelong disadvantage, says Hugh Drummond of the Universidad Nacional Autónoma de México in Mexico City.
Life doesn't start well for the younger chick or two in a booby nest. The oldest chick hatches almost four days before the second one, getting a head start on growing. It pecks any younger, smaller or weaker sibs, sometimes 60 times a day. The younger siblings grow submissive and by the end of their ordeal in the nest seem incapable of fighting back, Drummond said.
In the first week after hatching, for example, Drummond has found that bullied juniors typically lose out on about 17 percent of their fair share of food. But they generally experience a growth spurt later, catching up in weight with the oldest chick by the time they fledge.
If food gets too scarce though, the older sib becomes even more antagonistic and may kill the younger ones. Parents do not intervene.
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