Lion

A newly-crowned male lion usually kills all of the previous leader’s cubs. The father lion spends most of the day lying in the shade, waiting for the female lion to bring food. The female lion hunts and cares for the cubs, while the male lion’s job is to defend the territory from other prides and scavengers such as hyenas. The male lion is always the first to eat the prey, leaving only scraps of meat for the remaining members of the pride, including his cubs. If conditions are harsh, the leader will let his wife and cubs starve first.

Grizzly Bear

Rarely does a species in the animal world eat its cubs unless it is absolutely necessary, but male grizzly bears will. They are extremely territorial, able to defend ranges of up to 2,400 km, and are opportunistic hunters, willing to kill and eat anything that enters their territory, including their own cubs. This means that mother bears must not only provide food and teach their cubs to survive, but also ensure that the cubs never stray into their father’s territory.

Sea bass

Even a species as protective as male bass is prone to cannibalism. This behavior occurs after most of the young swim away and only a few remain. The male suddenly stops protecting his young from predators and swallows all the slow-moving fry as a reward for himself after helping the healthy ones survive.

Sand goby

Similarly, male sand gobies relentlessly guard their eggs against predators, but even when there is plenty of food available, they still eat about a third of the brood. The study revealed that male sand gobies decide which eggs to keep or eat based on size. Males tend to eat the largest eggs. In many species, larger offspring mean a higher chance of survival, making them the most protective members of the family. But the sand goby knows that the largest eggs take the longest to hatch. Eating the slowest-hatching egg will allow him to get out and return to mate as soon as possible.

Assassin bugs

The male assassin bug is tasked with guarding the eggs until they hatch. His strategy is to primarily feed on the outer edges of the egg sac, which are most likely to fall victim to parasitic wasps. This defense strategy is so effective that the assassin bug can completely avoid any potential parasites in the lab. Scientists believe that egg-eating is not only the only way to defend itself against parasites, but also provides nutrients for the male assassin bug when it cannot crawl around foraging.

An Khang (According to Mental Floss )