The amount of fat in human bodies is many times greater than that seen in any other land animal

From A Story of Us by Lesley Newson and Peter Richerson

Many mammals that live in seasonal habitats put on fat during the times when food is most plentiful, but the amount of fat in human bodies, particularly woman’s bodies, is extraordinary. It’s many times greater than that seen in any other land animal. The high fat levels aren’t just the result of living in modern societies with sedentary habits and an abundance of unhealthy foods. Women living in foraging societies with a lifestyle similar to that of our ancestors 100,000 years ago are nearly as fat—between 19 and 24 percent of their body weight is fat. What’s more, women’s bodies don’t function normally unless they have high levels of fat. The monthly cycle of ovulation and menstruation stops if a woman’s fat store falls much lower than 20 percent of her body mass.