Are Lions Social?

According to David Attenborough in Planet Earth II, episode 4 (Deserts), lions are most successful when they hunt and live in groups. But is this always true, and is it worth it? Lions are known to live in large prides, but we don’t always know why. Researchers have discovered that it’s harder for lions to obtain high-quality territory when they form very large groups, but it is easier to defend [3]. While hunting, lions only work together when necessary, when the prey is difficult to take down [2]. This reveals an evolutionary downfall of lions- they are sometimes weaker and slower than their prey [4]. This is just one of many examples of how evolution does not make animals perfectly suited to their environment. The reason lions often prefer to hunt alone is because they can eat their prey themselves rather than share it. For this reason, groups of 2-4 lionesses are at a disadvantage, since they cannot take down large prey yet must share their kills among their group [4]. The reason these lionesses still form groups demonstrates another evolutionary development. Research shows that lionesses that have cubs at a similar time and nurse their young together usually form life-long bonds and travel as a group [2]. While this may cause a disadvantage hunting, it also supports the survival of their cubs, who are better protected from attacks by aggressive male lions or other predators [2].

Regardless of these benefits, stereotypical group behavior of lions may change in the future. While threats from other lions seem to be the main danger faced by these powerful animals, humans have also had a grave impact on their survival, especially in recent years [1]. Contrary to popular belief, there used to be many subspecies of genetically unique lions [1]. This emergence of new groups was caused by geographic isolation and environmental differences [1]. However, whole populations of lions have been wiped out by poaching and the spread of human civilization, and many of the existing groups are endangered. This has lessened the genetic diversity of the species, since fewer populations remain, and less land is inhabitable for these animals. Lions may continue to evolve in response to these threats, and their social behavior could change. However, as land and food become scarce, will prides disappear?

(Planet Earth II. Season 1: Episode 4, Deserts, starting at approximately 5:35)

by Morgan Dommisse

References

1. Barnett, Ross, et al. 2014. Revealing the maternal demographic history of Panthera leo using ancient DNA and a spatially explicit genealogical analysis. BMC Evolutionary Biology 14(1): 70.
2. Packer, C, et al. 1990. Why Lions Form Groups: Food is not enough. The American Naturalist 136(1): 1–19.
3. Mosser, Anna, and Craig Packer. 2009. Group territoriality and the benefits of sociality in the African lion, Panthera leo. Animal Behaviour 78(2): 359–370.
4. Davidson, Z, Valeix, M, Van Kesteren, F, Loveridge, AJ, Hunt, JE, Murindagomo, F, & Macdonald, DW. 2013. Seasonal diet and prey preference of the African lion in a waterhole-driven semi-arid savanna. PLoS ONE 8(2): 1.