Although modern carnivores are a diverse group when it comes to diet, a typical carnivore feeds mostly on meat. Meat-eating carnivores tend to have a set of sharp-tipped teeth (carnassials), a characteristic of ancestral carnivores. Modified from molars, carnassials are specialized for slicing flesh. While meat is easier to digest, prey must be found, captured, and killed. Hunting collaboratively is sometimes more effective than hunting alone, and many large carnivores hunt in groups. Elaborate social behaviors have evolved around hunting, such as the dominance hierarchy in a pack of wolves. Even carnivores that do not hunt collaboratively, such as harbor seals and coatis, may live in social groups. Benefits of grouping may include sharing care of young or sharing defense of territory. Young carnivores must learn to hunt, which often means an extended training period. Carnivores have a high ratio of brain to body mass, allowing for the learning, coordination, and agility needed for hunting.

Thanks to their ability to produce milk, female mammals are able to feed their offspring for weeks, months, or even years after they are born. This sets the stage for the extended childhoods of many mammal offspring. With food and shelter taken care of (by the mother in most species), a remarkable amount of learning occurs for mammal offspring before they become independent. Elephants tend to their young for as long as 10 years, and humans for longer still. Young mammals may learn about food, shelter, migration routes, social structures, or other keys to survival from their parents. While extended childhoods support learning, they are costly, especially for the female. Lactating females must consume enough calories to feed their offspring and maintain themselves. Offspring that stay around after weaning from their mother's milk may still require protection and food. Human offspring are the most extreme case of investment, with parents usually providing intensive support until age 18 and continuing support beyond.