Animals That Go Through Menopause
You’ve got the air-conditioning cranked. You’ve invested in a white noise machine to help you get a little sleep. And your patience is wearing thin in a whole new way these days. There’s nothing fun about going through menopause, but ladies, did you know we’re not the only ones in the animal kingdom that suffer through it?
To be frank, we’re an oddity. Most animals keep on popping out babies until they reach old age. However, many toothed whales work a lot more like humans do where they reproduce for a number of years and then, when those years come to an end, they’ll keep right on trucking.
Let’s take a look at some animals in the wild that go through menopause:
1. Short-finned Pilot Whales
These whales can live up to 60 years. That is, if they’re female. Males usually die around the age of 45. Female Short-finned Pilot Whales reach sexual maturity when they turn about 10 years old. Once they reach that age they’ll begin to have their calves every five to eight years until they reach menopause.
2. Belugas
Belugas are long-lived creatures. They can live up to 75 years in the wild. That’s a lot of birthday candles to blow out! Females reach sexual maturity between eight and 14 years of age. Once they do, they will go on to have calves (one at a time) about every three years, until they reach menopause.
3. Narwhals
Female Narwhals reach sexual maturity between eight and 12 years of age. After which, they’ll have one calf at a time. They usually give birth to a new calf every three years, although it may even be longer. Eventually, their reproductive years end and they move into menopause, living up to 50 years (although most live less than 30 years).
4. Killer Whales
Killer Whales don’t live quite as long as these other whale species. Males will live on average 30 years, while females can expect to live until about 50 years of age. These social marine mammals don’t give birth to their first calf until they are about 15 years old. Once their reproductive years are through, they will take care of their young’s calves. Talk about a tight knit family!
What’s the Point?
So what’s the point of going through menopause and living on into our golden years? To be honest, it’s a bit of a mystery. Some researchers argue that we can thank the grandmother hypothesis. This idea suggests that older females will opt to support their grandbabies instead of going on to bear more of their own children or young.
While this idea works for social creatures like the Killer Whale, not all whale species are as social. And also…wouldn’t species like elephants evolve to have menopause? They’re awfully social and take care of their grandchildren and yet there are no signs that they go through menopause.
There doesn’t seem to be a clear cut answer as to why menopause exists in animals yet. What do you think?
April Overall
April is the Editor of Wildlife Update, CWF’s e-newsletter and WILD magazine, the Canadian Wildlife Federation's children’s publication. When she’s not writing for CWF, you’ll probably find her playing with her daughter Nora.
