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Turns out menopause might be an evolutionary trait to ensure the survival of a species

Only a few mammals live beyond child bearing years and human females are one of them.

Photo credit: Canva

Menopause might be evolutionary for human survival

Menopause can seem like one of those unfair things that only happen to those born with female reproductive systems. It's just one more thing to add to the list of things that those born of the opposite sex don't have to deal with. Menstrual cycles, hormonal and physical changes through pregnancy, the pain and recovery of childbirth, the pause in your career while caring for an infant, only to hit crescendo with menopause.

All those hormones that helped keep you balanced go careening off a cliff in the endocrine system. The whole process can feel unnecessary for those forced to experience it but there may be a reason menopause exists. Scientists have studied the phenomenon of menopause across different species. Turns out not every female animal goes through the process of shutting down reproductive organs.

For most animals, they reproduce until death, only experiencing menopause if there's something medically wrong or they're kept in captivity. Only three species of mammals live for a significant amount of time post reproductive years, orcas, short-finned pilot whales and humans. This revelation is what spurred "the grandmother hypothesis," which hypothesizes that these female mammal species live longer to ensure survival of the species.

blue and white whales Photo by NOAA on Unsplash

Both species of whales as well as humans assist their daughters in caring for their children. This allows the daughter to have more children, furthering the respective species. Yes, even whales help take care of their grandchildren by providing them food, which frees up their mother to reproduce sooner.

The Grandmother Effect, a 2009 study published in the National Library of Medicine shares, "women who remained vigorous beyond their fertile years may have enhanced their reproductive success by providing care for their grandchildren. This care would have enabled their daughters to resume reproduction sooner, endowing them with greater lifetime fertility. Genes of grandmothers possessing such old-age vigor would be more likely to persist in subsequent generations."

Short-finned Pilot Whale (Globicephala macrorhynchus) | Flickrwww.flickr.com

There were studies done on chimps as well since they're the closest animal to humans and the results were surprising. The majority of chimpanzees reproduce until death but Ngogo chimps seem to go through menopause around the same age as humans, 50. Ngogo chimps live several years after reproducing but unlike humans and whales, they have no interest in helping raise their grandchildren. In fact, the daughters move away from their mothers once they reach maturity.

Though the study spanned from 1995-2016 to collect accurate data through urine analysis of reproductive hormones, scientists point out that menopause may not naturally occur in Ngogo chimps. While the chimps are technically wild, they live in the Kibale National Park in Uganda. They are not hunted by prey, have an unnatural access to quality foods including more meat. Outside of the national park, nearby chimps don't live beyond 50 while the ones within the park live into their 60s.

woman wearing multicolored blanket hugging the baby Photo by Rahul Vaidya on Unsplash

The Ngogo chimps living an unnaturally long life inside the national park may explain why their familial behavior differs from those of humans and the two whale species. One study outside of the Demographic and hormonal evidence for menopause in wild chimpanzees attempts to debunk the grandmother hypothesis which shows nearly all mammals living beyond child bearing years but other scientists dispute their findings as all the animals studied were living in captivity, which greatly impacts lifespan.

In the 2018 study published in Ecology and Evolution, their study of 52 mammals holds firm that only three live beyond menopause, with humans spending 40-70% of their lives post menopause. So, though the grandmother hypothesis is still just that as scientists continue to look for further evidence, it may just be true. Humans have evolved to experience menopause to help further the species and since women live longer than men on average, it doesn't seem like a far leap. No pressure or anything, grandmas. No pressure at all. Just the survival of the human race, no biggie.

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Female bonobos shut down violent males. Here's what humans can learn from them.

Who run the bonobos world? GIRLS!

Hey ladies, you know that uncomfortable moment when you're at a bar with your girlfriends and some sketchy dude comes over to hit on one of you?

Maybe this dude elbows his way into your conversation or maybe he leans too close and tries to buy a round of drinks. Then maybe he not-so-subtly drapes a sweaty hand on one of your shoulders? Yeah, it sucks.

Image via iStock

If that sounds familiar to you, then you'll probably recognize what happens next because it's kind of awesome: Your friends close ranks and block the dude's unwanted approach.

Even more awesome? This behavior isn't limited to humans.

Scientists at the Primate Research Institute at Kyoto University have observed female bonobos employing similar behaviors when a female in their group feels threatened by a male.

In fact, according to a four-year study on bonobos (cousins to chimpanzees) conducted in the Congo, female bonobos purposely form all-female groups to keep aggressive males at bay.

Females of all ages from different families would come together in these groups, with the older bonobos looking out for the younger ones by keeping them in the center of a protective circle. Researchers even found that female bonobos from different families were incredibly tolerant of one another, and that female-on-female bonobo aggression was surprisingly rare.

Bonobos females holding each other. Photo via Georges Gobet/Getty Images.

Nahoko Tokuyama, the leader of the study, believes this ability to get along is the key to female dominance in the bonobo population.

In species that display what humans might call "stereotypically gendered behavior," males are more often observed using aggressive tactics to coerce copulation and/or acquire higher social status. This could be anything from a male trying to mate with a female to a male bonobo feeding on a tree that a female bonobo has claimed as hers.

Sound familiar? Yeah.

But in the Kyoto University study, researchers noticed female bonobo grouping together to prevent this kind of male aggression. They called these groups "female coalitions," but you or I might describe them as "deep female friendships."

If there's one thing males in pretty much every species know, it's not to mess with a group of angry women. Photo by Mark Dumont/Flickr.

If one female in a coalition attacked a male for any reason, the rest would follow suit and come to her aid.

According to Tokuyama, 69% of these female coalitions were observed forming after or during an incident of aggressive male behavior.

What's more, female coalitions rarely (if ever) lose to a male aggressor, and because the male bonobos know they can't win, they're less prone to acting out with aggression or violence in the first place.

"Males frequently direct display and charge toward females, but they seldom attack females physically, even though males are bigger," Tokuyama told Upworthy.

A coalition of female bonobos attacking an offending male. GIF via animal coalition/YouTube.

Of course, meeting aggression with aggression might not sound like the best approach to conflict resolution. And this isn't to say that bonobos of all genders are inherently violent either. But these female coalitions have been so effective that they've virtually eliminated violent outbreaks in the bonobo population.

GIF from "Game of Thrones."

Another reason researchers think bonobo groups are less aggressive than their chimp cousins? Sex. Lots of it.

Researchers have observed bonobos engaging in all kinds of sexual acts — not just heterosexual intercourse. They're down with everything from same-sex sex to masturbation to oral sex to group sex and also, uhhh, rubbing each others' genitals as a form of casual greeting when a new group comes into the area.

We humans might be inclined to call that "kinky." But to them, it's just a very, very friendly way of saying, "Hello, how are you today?"

Self-explanatory. Photo by Jaume F. Lalana/Flickr.

Of course, we can't know for certain whether bonobos are actually engaging in this behavior for pleasure.

But whatever the reason, it has helped to decrease the number of tense confrontations between individuals and groups. When everybody's gettin' it on on the reg — for pleasure, not for force — then the whole group is generally calmer and less violent.

Contrast this to the observed behavior of their chimpanzee cousins. They have plenty of sex, but theirs appears to be more about power and dominance than personal or shared pleasure. They're known to engage in rape, murder, and infanticide, and they are more likely to have violent interactions with newcomers.

(Again: sound familiar?)

Anthropological data analyzed by neuropsychologist James Prescott suggests societies that are more sexually open are also less likely to be violent. The key to understanding this correlation, however, is that it's the society as a whole that is more sexually open and not just a small percentage of individuals.

Photo by Ted/Flickr.

So, to bring it back to that guy approaching a group of women at the bar: is there anything we as humans can learn from bonobos?

It's pretty clear the combination of female coalitions of bonobos defending their own, and bonobos of all genders engaging in casual sex seems to have resulted in a less violent ape society. (In this case, let's assume that "sex" means "pleasure and fulfillment.)

While bonobos' behavior doesn't exactly translate to modern human society, it is an important reminder that if humans work to ensure that everyone has the opportunity to feel fulfilled and to feel pleasure on a regular basis, we may find ourselves living in a less violent, less aggressive society.

It's really as simple as that.

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Take an inside look at a home dedicated to saving orphaned chimpanzees.

The chimpanzee population in West Africa has declined sharply over the past few decades — more than 90% in Côte d'Ivoire alone.

Project Primates, a U.S.-based not-for-profit group, is working to preserve and protect these beautiful creatures and their habitats. That's why they launched the Chimpanzee Conservation Center (CCC).

Ten-month-old Soumba is left alone momentarily for the first time since her arrival at the Chimpanzee Conservation Center in 2015. Photo by Dan Kitwood, Getty Images Reportage.

The Chimpanzee Conservation Center rescues, rehabilitates, and, when possible, releases healthy chimps back into the wild.

The CCC, located inside the Haut Niger National Park in the West African nation of Guinea, is home to 50 young, orphaned western chimpanzees who are often sold into the pet trade after their mothers and other adult family members are killed for bushmeat.

Volunteer Anissa Aidat holds new arrival Kandar. Photo by Dan Kitwood, Getty Images Reportage.

When the chimpanzees arrive at the sanctuary, they often suffer from diseases related to their captivity.

Veterinary volunteer Christina Collell performs a health check on new arrival Kandar. Photo by Dan Kitwood, Getty Images Reportage.

Respiratory and skin diseases are common, as are malnutrition and psychological conditions, all of which require round-the-clock care.

Anissa Aidat gives N'Dama a milk substitute. Photo by Dan Kitwood, Getty Images Reportage.

After a brief period of quarantine, keepers care for the animals in age-appropriate habitats.

The CCC is just over 3,700 square miles of dry forest and grassland. There, with the help of staff and volunteers, the animals learn how to be wild animals, something few of the animals had the chance to experience.

Keeper Fayer Kourouma with a chimp during a hike. Photo by Dan Kitwood, Getty Images Reportage.

They make nests, go for walks in the bush, forage, learn to climb, and discover how to communicate and work with other chimpanzees.

Photo by Dan Kitwood, Getty Images Reportage.

As the chimps get older and more reliant on their peers, human contact is limited to better prepare them for release and life in the wild.

Keeper Fayer Kourouma and a chimp share sugarcane. Photo by Dan Kitwood, Getty Images Reportage.

This rehabilitation process requires lots of patience. Preparing a chimp to return to the wild can take more than 10 years!

The CCC released its first group of chimpanzees in 2008, right in the Haut Niger National Park, not far from the sanctuary. The animals are equipped with tracking devices to monitor their location, and since the sanctuary is so close to the release site, volunteers and staff can protect the animals from poachers and other threats. So far, the released chimpanzees are thriving and interacting with the wild population. It's truly the best outcome, and hopefully a sign of good things to come.

Keeper Albert Wamouno and Hawa. Photo by Dan Kitwood, Getty Images Reportage.

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3 comforting lessons about grief we can learn from the animal kingdom.

Image via Pixabay.

Dealing with grief takes time... lots of time.

Did you know that grief is not just a human emotion? Behaviors of grief have also been observed in other species.

You've probably heard stories like the dog lying beside his owner's casket, but beyond the anecdotes is enough scientific observation to suggest that many animals experience what we could call grief symptoms.

Here are three things we can learn about grieving from the animal kingdom:


1. Getting over a traumatic loss doesn't happen overnight. Animals have been observed staying near the bodies of companions for days.

While you're going through the stages of grief, it's important to remember that your mission isn't to feel better right away or even as soon as you can.

When cameraman Mark Deeble was following an elephant family in Kenya for the documentary series "Africa," he observed a mother mourning the loss of her calf. She stayed next to the body for over an hour.

"In a more benign environment, an elephant might mourn for longer," James Honeyborne, a wildlife filmmaker, wrote in The Daily Mail. "I have heard of animals staying beside the bodies of dead friends for three days and nights, refusing to move."

Geese, which are notably loyal animals, often mourn in seclusion for a long time when their mate dies. Some will even refuse to take another mate ever again.

Grief is a long and slow process. You shouldn't put pressure on yourself to get better in a day, or a week, or even a year. There are no time limits to your feelings. As psychotherapist Martha Clark Scala writes:

"You may start to feel better in three months, but don't be surprised if you're still miserable, at least some of the time, several months to several years after your loss. The average length of time it takes most people to consistently feel better is about a year. However, it's also common to feel better for a while and then take a turn for the worse. That can be triggered by events such as special holidays or occasions that have a particular association with the person you've lost, especially the anniversary of his or her death."

Whether it's anger, guilt, or unbearable sadness, your emotions are what they are. Don't hide from them or try to push them down. Give yourself the time and space you need to really embrace your feelings. It will help you heal.

2. Having the comfort of close friends nearby can help you process your feelings. Multiple primate species have been observed mourning as a group.

In 2008, a volunteer at a chimpanzee rescue shelter named Monica Szcupider took a now-iconic photograph of chimps lining up at the fence of their enclosure to watch as the body of Dorothy, one of their fellow chimps, was wheeled away.

"Her presence, and loss, was palpable, and resonated throughout the group," Szcupider said.

When you lose someone close to you, it's important to remember that you're not alone, even if you feel that way. Leaning on friends and family can be a key part of the healing process.

A snub-nosed monkey fell to her death in front of her partner at an observatory in China. The rest of her group ran over to her, holding her hand and giving her comfort for nearly an hour as she lay dying. The lead male of her group stayed by her side longer than anyone and kept glancing back at her even once he rejoined his group at a nearby river.

Deaths rarely affect just one person. Being with other people who are feeling the same loss can bring you all closer together as you help each other come to terms with the trauma.

3. Death can be hard to accept. Some animals have been observed participating in behaviors suggesting they're in denial.

"The first reaction to learning of terminal illness or death of a cherished loved one is to deny the reality of the situation," writes Julie Axelrod at Psych Central. "It is a normal reaction to rationalize overwhelming emotions. It is a defense mechanism that buffers the immediate shock."

A gorilla in Germany was documented holding the body of her deceased baby for a week, trying in vain to restore life to him. Dolphins have also been known to carry dead loved ones on their backs for long periods of time, trying to buoy them and get them to swim again.

These stories are tragic, but denial is often a normal part of the grieving process for both animals and humans.

Denial is not the same as refusal to accept reality, though there are certain warning signs you can pay attention to if your natural denial phase is becoming unhealthy.

But getting from denial to acceptance that a loved one has passed is hard, and the road to recovery takes many forms and has many stages. Denial doesn't mean you're crazy or unable to cope — it's just one way the brain can react.

The biggest takeaway? Regardless of species, grief is a totally natural part of life.

Losing someone you love is incredibly painful, and the grieving process means you might be hurting for a long time. But it's something we go through, humans and animals alike.

You may think you're wrong for feeling as bad as you do, or for crying as much as you want to cry. You're not. The confusing, terrifying, maddening, and isolating process known as mourning is both natural and kind of amazing.

It's amazing because it means you were lucky enough in your life to love someone so much that their loss can hurt this bad. Cherish the happy memories you have. Those aren't going anywhere.

Death and heartbreak are a part of life for both humans and animals. But so are happiness and fulfillment.

And so is healing.


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