See First Ever Video of an Orca Mother and Son Killing a Calf

This is the first reported account of an adult male orca and its mother killing the calf of an unrelated female. Researchers suggest the behaviour was sexually motivated. The adult male took the calf by the tail and dived deep underwater ... while its mother blocked the calf’s mother from pursuing its child.

The male orca drowned the calf in hopes the young mother would then be willing to mate. This behaviour isn't so rare in the animal kingdom. Lions, rodents, and even primates have been known to do this, too.