cainism
siblicide

In Scotland, there may be a weak link between food supply and cainism.

Cainism is frequent, even typical in species of the Aquila genus.

What you're interested in, I guess, is Cainism and Manicheanisra.

Cainism", as it is sometimes called, or siblicide is inarguably the most controversial and confusing aspect of the golden eagles' reproductive biology."

He challenged the pessimistic and somber tones in the new poems, and he detested the foreign poetic movements of cainism, satanism, and, generally, all the isms.

There are conflicting opinions on this phenomenon also called cainism-"No evidence [exists] of sibling aggression, but youngest in brood of 3 almost always dies of starvation..."

Although the brooding mothers, otherwise famous for the high level of their parental care, is fully aware of the sibling aggression, in no raptorial bird species are they known to intervene when cainism occurs.

It is possible that cainism is more common when the older hatchling happens to be a female but, in many cases of males hatching first, they are still larger than the younger siblings and often do dominate and kill them whether male or female.