Group living
Most daughters are recruited into their mothers’ pride although about a third disperse to form new prides; pride size ranges from 1–21 females, and mid-sized prides enjoy the highest reproductive rates, and females in the same pride breed at similar rates. Young males always leave home in search of unrelated mates. Coalition size varies from 1–10 males, and coalitions of 4–10 males consist entirely of males born in the same pride, whereas pairs and trios often include unrelated individuals. Although larger male coalitions enjoy higher per capita reproductive success, reproduction is only equally shared in small coalitions.
Lions are most affectionate to their like-sexed companions. Females spend their lives in their mothers’ pride or with their sisters in a new pride; males may only spend a few years in a given pride but remain with their coalition partners throughout their lives. Read more about group living.
Infanticide
Mothers directly defend their offspring against attacks by outside males, and females also reduce the risks of infanticide by inciting competition between rival males such that they only conceive again after the largest available coalition has become resident in their pride.
Female lions will kill the cubs of rival prides, but they never kill the cubs of their pridemates. The “egalitarianism” of female lions is strikingly different from the despotic behavior of wolves, wild dogs and many other species where dominant females prevent subordinates from breeding.
Communal cub rearing
The primary advantage of forming a crèche is that a group of females is better able to protect their young against infanticide. Males are 1.5 times larger than females, so a male can easily overpower a lone mother, whereas a crèche with at least two mothers can successfully protect at least some of their cubs against an extra-pride male. However, the crèche can only withstand a brief male incursion, so the females must also rely on protection from their resident males, who patrol the pride territory and fiercely repel outside males.
Territoriality
The lion’s roar is a territorial display that can be heard from at least five km away. Lions are able to count the number of individuals in a roaring group and will challenge the invaders if they safely outnumber them.
Although foraging groups of lions often suffer reduced food intake from having to share their kills with pridemates, larger prides have a strong advantage in competition against neighboring groups. Larger prides are able to expand the size and quality of their territories and thereby gain greater reproductive success. The heterogeneity of savanna habitat appears to be the root cause of group territoriality in lions: territory quality largely depends on proximity to river confluences, which serve as funnels that force prey into a small area and also hold persistent waterholes and dense vegetation.