Grandmother killer whales boost the survival rates of their grandchildren, study finds
Female killer whales are one in just five animals that experience menopause, including humans
Your support helps us to tell the story
From reproductive rights to climate change to Big Tech, The Independent is on the ground when the story is developing. Whether it's investigating the financials of Elon Musk's pro-Trump PAC or producing our latest documentary, 'The A Word', which shines a light on the American women fighting for reproductive rights, we know how important it is to parse out the facts from the messaging.
At such a critical moment in US history, we need reporters on the ground. Your donation allows us to keep sending journalists to speak to both sides of the story.
The Independent is trusted by Americans across the entire political spectrum. And unlike many other quality news outlets, we choose not to lock Americans out of our reporting and analysis with paywalls. We believe quality journalism should be available to everyone, paid for by those who can afford it.
Your support makes all the difference.The presence of post-menopausal female killer whales boosts the survival rates of their grandchildren thanks to the “wisdom” they offer, a new study has found.
Grandmother killer whales who can no longer reproduce have more time to help their grandchildren during difficult periods when food is scarce compared to female whales who can still reproduce.
Just five animals are known to experience menopause, including killer whales, short-finned pilot whales, belugas, narwhals, and humans.
Researchers were attempting to understand why female killer whales live for many more decades after their ability to reproduce has halted.
The study was carried out by the University of York and University of Exeter, alongside the Centre for Whale Research in the US and Fisheries and Oceans Canada.
The findings were published in the Proceedings of the National Academy of Sciences journal, and point towards a better understanding of why menopause has evolved in certain animals.
Senior author Dan Franks, from the University of York, told the BBC: “If a grandmother dies, in the years following her death, her grand-offspring are much more likely to die.”
He added that from an evolutionary perspective, females who live a long time after reproduction “can still pass on their genes and genetic legacy by helping their grand-offspring”.
The research also suggests that post-reproductive grandmothers avoid conflict daughters and reduce competition for food among their children.
Killer whales are highly social animals and their societies are matriarchal. This research further emphasises the importance female killer whales have within the species’ social structures.
Some behaviour suggests grandmother killer whales “babysit” their grandchildren while the mother goes hunting for fish, said Franks.
He said researchers will use drone footage to observe the behaviour and gain a better understanding of the interactions within pods in a future project.
Darren Croft from the University of Exeter, who co-authored the study, said: “Our new findings show that just as in humans, grandmothers that have gone through menopause are better able to help their grand-offspring and these benefits to the family group can help explain why menopause has evolved in killers whales just as it has in humans.”
Additional reporting by agencies
Subscribe to Independent Premium to bookmark this article
Want to bookmark your favourite articles and stories to read or reference later? Start your Independent Premium subscription today.
Join our commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies
Comments