6 | Are Grandmothers the Key to Our Evolutionary Success? ~ Kristen Hawkes

On Humans

Humans live long, much longer than any of our closest relatives. For human females, this means living a large part of adulthood without being able to produce new offspring. This is an evolutionary puzzle. Indeed, menopause is exceedingly rare in the animal kingdom, typical only in humans and some species of whales.

Kristen Hawkes has a theory to explain this puzzle. Hawkes is an evolutionary anthropologist, best known for her pioneering role around the so-called “grandmother hypothesis”.

In this episode, Ilari and Professor Hawkes discuss two aspects of the grandmother hypothesis. First, why would humans have evolved to survive menopause? And second, why is this a big deal? What were the cascading changes that surviving the menopause arguably triggered?

The conversation touches upon many topics, such as:

• Grandmother hypothesis: the basics
• Rapid birth intervals in humans
• Pair bonding and romantic partnerships
• Role of fathers (and grandfathers)
• Brain size and brain development
• The “social appetite” in humans
• Humans vs chimpanzees: why are humans less competitive and more cooperative
• Climate changes and human origins

Technical terms & ethnic groups mentioned

• The Hadza (Tanzania)
• The Ache (Paraguay)
• Pliocene (5.3 million – 2.6 million years ago)
• Australopithecus (Wikipedia)
• Altricial (undeveloped, immature) vs precocial (well-matured early on) (Wikipedia)
• Mau Mau rebellion (a 1950’s rebellion against British rule in Kenya which included systemic torture by British colonial officers, Wikipedia)

Names mentioned

• Jane Goodall
• Nicholas Blurton Jones
• James (Jim) O’Connell
• Geoff Parker
• Richard Wrangham
• Sherwood Washburn
• Sarah Blaffer Hrdy
• Barbara Finlay

References

• A 1998 overview of the grandmother hypothesis (by Kristen Hawkes)
• Calories produced by mothers and grandmothers in the Hadza (by Kristen Hawkes)
• Distorting Darwinism (by Ilari)