University of Exeter – August 27, 2018
Scientists have discovered that beluga whales and narwhals go through the menopause—taking the total number of species known to experience this to five. Aside from humans, the species now known to experience menopause are all toothed whales—belugas, narwhals, killer whales and short-finned pilot whales.
Almost all animals continue reproducing throughout their lives, and scientists have long been puzzled about why some have evolved to stop. The new study, by the universities of Exeter and York and the Center for Whale Research, suggests menopause has evolved independently in three whale species (it may have evolved in a common ancestor of belugas and narwhals).
“For menopause to make sense in evolutionary terms, a species needs both a reason to stop reproducing and a reason to live on afterwards,” said first author Dr. Sam Ellis, of the University of Exeter.