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‘Reproductive conflict’ could explain menopause
The mortality of older mothers’ offspring is 1.7 times that of younger mothers’ offspring.
Older orcas face higher offspring mortality than daughters - study
 
Conflict between mothers and daughters could explain why orcas are one of only three species - including humans - that go through the menopause.

Female orcas generally stop reproducing in their 30s and 40s but, just like humans, they can live for many decades after menopause.

Led by Darren Croft of the University of Exeter, an international team studied 43 years of data gathered by the Centre for Whale Research and Fisheries and Oceans Canada. They found the mortality of older mothers’ offspring is 1.7 times that of younger mothers’ offspring.

One of the main reasons for this ‘reproductive conflict’ between mothers and daughters is their reliance on food sharing. They forage together and often share salmon, with offspring commonly relying on their mothers for food for years.

Previous research by the team showed that post-reproductive orcas play a ‘grandmother’ role, sharing knowledge of when and where to find food, which increases survival chances for their family group.

Professor Croft explained: “Our previous work shows how old females help but not why they stop reproducing. Females of many species act as leaders in late life but continue to reproduce, but this new research shows that old females go through the menopause because they lose out in reproductive competition with their own daughters.”

Co-author Dr Daniel Franks, from the University of York, added: “…Our new work shows that if an old female killer whale reproduces her late-life offspring suffer being out-competed by her grandchildren. This, together with her investment in helping her grandchildren, can explain the evolution of menopause.”

Follow up work by the team will involve the use of drones to study orca behaviour more closely, including closer analysis of mother-daughter conflicts.

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Newborn okapi named after Meghan Markle

News Story 1
 An endangered okapi recently born at London Zoo has been named Meghan - after Prince Harry’s fiancé Meghan Markle - in celebration of the upcoming royal wedding. Okapis are classed as endangered in the wild, having suffered ongoing declines since 1995. Zookeeper Gemma Metcalf said: “We’re very pleased with how mother and baby are doing. Oni is being very attentive, making sure she regularly licks her clean and keeping a watchful eye over Meghan as she sleeps.” Image © ZSL London Zoo  

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Ten new cases of Alabama rot confirmed

Anderson Moores Veterinary Specialists has confirmed 10 new cases of Alabama rot, bringing the total number of confirmed cases in the UK to 122.

In a Facebook post, the referral centre said the cases were from County Durham, West Yorkshire, Greater Manchester, Staffordshire, Sussex, West Somerset, Devon, and Powys.

Pet owners are urged to remain vigilant and seek advice from their vet if their dog develops unexplained skin lesions/sores.