Not all animals mothers are cold-hearted killers, but the passivity of the otherwise assertive lioness is a bit surprising. Most wildlife images portray the lioness as a protective and caring mother, which she generally is. The problems begin when a new male takes over a pride. With a new stud on the scene, mommy lion turns a blind eye to any cubs under the age of 2 years old. The new male kills the cubs to stop any future rivals challenging him for the pride, and also to encourage the lionesses to go into heat, allowing him to begin his own dynasty. Such is the cost of becoming queen.