Scientists have found menopause among narwhals and Beluga whales
British biologists have found that females are two mammals, narwhals, and belugas — are experiencing a condition similar to menopause: their ability to reproduce ends long before the end of life.
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British biologists have found that females are two mammals, narwhals, and belugas — are experiencing a condition similar to menopause: their ability to reproduce ends long before the end of life. It was able to show through analysis of the ovaries of 16 cetaceans. As reported in an article published in the journal Scientific Reports, this finding increases the number of known species with post-reproductive period of life to five.
Females of most mammals do not lose their ability to reproduce throughout the time from reaching reproductive age to death. However, representatives of some species, the reproductive capacity is lost at a certain age. Such species include, of course, man: in women, menopause (the period after the last self-menstruation) occurs, on average 45-50 years. In addition to people post-reproductive period was also observed in two other species: females of killer whales (Ornicus orca) and korotkoplodnyh pilot whales (Globicephala macrorhynchus), which cease to reproduce at the age of forty, and then live an average of 10-15 years.
As a killer whale, and pilot whale — the representatives of the suborder of toothed whales (Odontoceti), you can make the assumption that among the kindred mammals there are other species females which are experiencing a postreproductive period. To test this hypothesis the researchers decided their Exeter University under the guidance of Darren Croft (Darren Croft).