Some species of toothed whales, such as belugas and orcas, have lengthened their lives without increasing their reproductive capacity; thus being able to look after their children and grandchildren to ensure their survival

Some species of toothed whales, such as belugas and orcas, have lengthened their lives without increasing their reproductive capacity; thus being able to look after their children and grandchildren to ensure their survival

Source: livescience.com

https://www.livescience.com/animals/whales/why-some-whales-go-through-menopause