The article explores the evolution of menopause in toothed whales, comparing it to humans. Menopause, the cessation of reproduction in females, is rare in mammals but has evolved multiple times in toothed whales. The study uses a comparative database to test evolutionary hypotheses. It finds that menopause in toothed whales evolved by extending lifespan without increasing reproductive lifespan, aligning with the 'live-long' hypothesis. This suggests that menopause allows females to provide intergenerational help by increasing lifespan overlap with grandoffspring and offspring without increasing reproductive overlap with daughters. The findings support the idea that menopause in humans and toothed whales evolved through similar mechanisms, involving extended lifespan and intergenerational support. The study also highlights the role of kinship and social structures in the evolution of menopause, showing that species with menopause have longer lifespans and more opportunities for intergenerational help. However, they do not show increased reproductive overlap with their daughters. The research underscores the importance of social and demographic factors in the evolution of menopause, providing insights into the broader evolutionary mechanisms of life history traits.The article explores the evolution of menopause in toothed whales, comparing it to humans. Menopause, the cessation of reproduction in females, is rare in mammals but has evolved multiple times in toothed whales. The study uses a comparative database to test evolutionary hypotheses. It finds that menopause in toothed whales evolved by extending lifespan without increasing reproductive lifespan, aligning with the 'live-long' hypothesis. This suggests that menopause allows females to provide intergenerational help by increasing lifespan overlap with grandoffspring and offspring without increasing reproductive overlap with daughters. The findings support the idea that menopause in humans and toothed whales evolved through similar mechanisms, involving extended lifespan and intergenerational support. The study also highlights the role of kinship and social structures in the evolution of menopause, showing that species with menopause have longer lifespans and more opportunities for intergenerational help. However, they do not show increased reproductive overlap with their daughters. The research underscores the importance of social and demographic factors in the evolution of menopause, providing insights into the broader evolutionary mechanisms of life history traits.