Overview

• Menopause in toothed whales evolved to extend females' lifespans, enabling them to care for grandchildren without competing with their daughters.
• The study, published in Nature, is the first to examine menopause across several species of toothed whales.
• Only six mammal species, including humans and five species of toothed whales, are known to experience menopause.
• The findings support the 'grandmother hypothesis,' suggesting that menopause evolved to increase the survival of offspring's offspring.
• Researchers caution that studying whale demography is challenging due to biases and small sample sizes in available data.