'Grandma effect' in killer whales

A study of 378 killer whales cared for by her whales showed that they lived longer than others. She whales help them find food when they are scarce.

"Doting" killer whales can help their grandchildren survive even in difficult times. Scientists have announced this after studying the female whales of reproductive age.

Female killer whales will stop breeding at the age of 30-40, but they can live for a few more decades. In particular, this only happens in humans and four whales, according to the Guardian.

Human studies have shown that the fact that grandparents helping to care for their children has partly stimulated the desire to have children in young people, called the 'grandmother effect' . However, this theory has so far not been tested in whales.

'This is the first menopausal animal that works with the' grandmother hypothesis 'after humans , ' said study author Daniel Franks from York University.

'It works with whales, but this species can breed until the end of life. Only five species that have experienced menopause are humans, killer whales, short-finned round whales, unicorns and beluga whales , ' he added.

The killer whale that takes care of her grandchildren makes them live longer.(Photo: Guardian).

The team of scientists from the University of Exeter, the American Whale Research Center and the Pacific Pacific Biological Station of Canada focused their research on 378 whales that were cared for by their grandmothers.

Results showed that whales whose grandmothers died prematurely had a 4.5-fold higher mortality rate than those whose grandmothers were still alive.

This effect is greatly amplified during years of fish scarcity.

'Previously, we knew that postmenopausal fish often led groups to hunt for food. They play an important role when needed, such as when scarcity of salmon (whale food), '' Mr. Franks said.

'They are willing to share food with their children and grandchildren. We think that (whale grandmother) is taking care of her grandchild. '

While studies of the 'grandmother effect' in whales are still underway, there is no explanation for why killer whales lose fertility in middle age.

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