If you could be one age for the rest of your life, what would it be?

Would you choose to be nine years old, spending your days playing with friends and practicing your times tables?

Or would you choose your early 20s, when time feels endless and the world is your oyster with friends, travel, pubs, and clubs?

Western culture idealizes youth, so it may come as a surprise to learn that in a recent poll asking this question, the most popular answer wasn’t 9 or 23, but 36.

Yet as a developmental psychologist, I thought that response made a lot of sense.

adulthood, turning 36, developmental psychology, life satisfaction, emotional maturity, career crunch, parenting, aging, 30s life, peak happiness
36 is the magic number. Canva

For the last four years, I’ve been studying people’s experiences in their 30s and early 40s, and my research has led me to believe that this stage of life, while full of challenges, is much more rewarding than most might think.

The career and care crunch

When I was a researcher in my late 30s, I realized that no one was doing research on people in their 30s and early 40s, which puzzled me. So much often happens during this time: Buying homes, getting married or getting divorced; building careers, changing careers, having children or choosing not to have children.

self-confidence, mental health, midlife, adult friendships, work-life balance, life stages
According to one respondendant things Canva

To study something, it helps to name it. So my colleagues and I named the period from ages 30 to 45 “established adulthood” and then set out to try to understand it better. While we are still collecting data, we have interviewed over 100 people in this age cohort and collected survey data from more than 600 additional people.

We went into this large-scale project expecting to find that established adults were happy but struggling. We thought there would be rewards during this period of life, perhaps being settled in career, family, and friendships, or peaking physically and cognitively, but also some significant challenges.

The main challenge we anticipated was what we called “the career and care crunch.”

This refers to the collision of workplace demands and the demands of caring for others that occurs in one’s 30s and early 40s. Trying to climb a ladder in one’s chosen career while also being increasingly expected to care for kids, tend to the needs of partners and perhaps care for aging parents.

Yet when we started to look at our data, what we found surprised us.

Yes, people were feeling overwhelmed and talked about having too much to do in too little time. But they also talked about feeling profoundly satisfied. All of these things that were bringing them stress were also bringing them joy.

For example, Yuying, 44, said, “Even though there are complicated points of this time period, I feel very solidly happy in this space right now.” Nina, 39, simply described herself as being “wildly happy.” (The names used in this piece are pseudonyms, as required by research protocol.)

When we took an even closer look at our data, it started to become clear why people might wish to remain age 36 over any other age. People talked about being in the prime of their lives and feeling at their peak. After years of working to develop careers and relationships, people reported feeling as though they had finally arrived.

Mark, 36, shared that, at least for him, “things feel more in place.” “I’ve put together a machine that’s finally got all the parts it needs,” he said.

A sigh of relief after the tumultuous 20s

As well as feeling as though they had accumulated the careers, relationships and general life skills they had been working toward since their 20s, people also said they had greater self-confidence and understood themselves better.

Jodie, 36, appreciated the wisdom she had gained as she reflected on life beyond her 20s:

“Now you’ve got a solid decade of life experience. And what you discover about yourself in your 20s isn’t necessarily that what you wanted was wrong. It’s just you have the opportunity to figure out what you don’t want and what’s not going to work for you. So you go into your 30s, and you don’t waste a bunch of time going on half dozen dates with somebody that’s probably not really going to work out, because you’ve dated before and you have that confidence and that self-assuredness to be like, ‘Hey, thanks but no thanks.’ Your friend circle becomes a lot closer because you weed out the people that you just don’t need in your life that bring drama.

Most established adults we interviewed seemed to recognize that they were happier in their 30s than they were in their 20s, and this impacted how they thought about some of the signs of physical aging that they were starting to encounter. For example, Lisa, 37, said, “If I could go back physically but I had to also go back emotionally and mentally no way. I would take flabby skin lines every day.”

Not ideal for everyone

Our research should be viewed with some caveats.

The interviews were primarily conducted with middle-class North Americans, and many of the participants were white. For those who are working class, or for those who have had to deal with decades of systemic racism, established adulthood may not be so rosy.

It is also worth noting that the career and care crunch has been exacerbated, especially for women, by the COVID-19 pandemic. For this reason, the pandemic may be leading to a decrease in life satisfaction, especially for established adults who are parents trying to navigate full-time careers and full-time child care.

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At the same time, that people think of their 30s and not their 20s or their teens as the sweet spot in their lives to which they’d like to return suggests that this is a period of life that we should pay more attention to.

And this is slowly happening. Along with my own work is an excellent book recently written by Kayleen Shaefer, “But You’re Still So Young,” that explores people navigating their 30s. In her book she tells stories of changing career paths, navigating relationships and dealing with fertility.

My colleagues and I hope that our work and Shaefer’s book are just the beginning. A better understanding of the challenges and rewards of established adulthood will give society more tools to support people during that period, ensuring that this golden age provides not only memories that we will fondly look back upon but also a solid foundation for the rest of our lives.

Clare Mehta is an Associate Professor of Psychology, Emmanuel College. This article originally appeared on The Conversation. You can read it here.

This article originally appeared last year.

  • Humans nearly vanished 800,000 years ago, revealing a quiet truth: most family lines disappear
    Photo credit: CanvaA group of people hiking in the mountains.

    There was a moment in human history when our entire existence may have desperately clung to a thousand or so people. A DNA-based study found that between 800,000 and 900,000 years ago, our ancestors experienced a severe population crash.

    This wasn’t humans dealing with a giant meteor like the one that wiped out the dinosaurs. It was a much slower stretch during which humanity teetered on the brink of disappearing completely. This bottleneck in the human gene pool, comprising roughly 1,280 breeding individuals, lasted about 117,000 years.

    population, genomes, Ice Age, Early-Middle Pleistocene
    Removing representation of a human population group.
    Photo credit: Canva

    Human population levels plummet

    According to Scientific American, the study analyzed modern human genomes to piece together what the early human population looked like. By constructing a complex family tree of genes from present-day humans, researchers were able to identify important evolutionary events.

    During the Early-Middle Pleistocene, a period within the Ice Age, humans faced severe weather and intense glacial cycles. Most human ancestors may have died out, clearing the path for a new human species to take their place.

    Focusing on Africa, the study showed that 813,000 years ago, human populations began to recover and grow again. With an estimated two-thirds of genetic diversity potentially lost, traits like brain size appear to have been among the important features that survived. “It represents a key period of time during the evolution of humans,” population geneticist and study co-author Ziqian Hao said. “So there are many important questions to be answered.”

    DNA, genomes sequence, human existence, heredity
    DNA genome sequences.
    Photo credit: Canva

    Understanding evolution and ancestry

    What we know about evolution reveals a different story than a simple, continuous line of human improvement. Over time, genetic lines disappear—not dramatically all at once. It’s a slow and steady change, generation after generation.

    Human existence isn’t inevitable. Species strength or technical advancement doesn’t guarantee the future or explain our past. It’s contingent on narrow, accidental circumstances. A 2021 study showed that human evolution is better seen as a continuous flow of incremental fragments over time. Categorizing people into races and groups oversimplifies human history.

    species strength, evolutionary improvement, genetic lines, technical advancement
    A diverse group of wooden figures.
    Photo credit: Canva

    What does the bottleneck study say about us?

    The study reveals humanity didn’t simply decline; it nearly collapsed. With over 98% of our genetic diversity erased, entire branches of the human family tree permanently ceased to exist.

    It’s quite possible that if even a few more of those genetic lines had ended, human history could have vanished with them. Most branches of life don’t continue. What we witness today reflects biological persistence and countless moments that could have gone another way.

    A 2024 study conducted five billion simulations, revealing that as a species’ population shrinks, its risk of extinction rises. Even stable groups can quickly collapse if their numbers suddenly drop low enough.

    A 2025 study found that small populations erode genetic diversity. Isolation increases inbreeding and elevates the risk of extinction. Once a lineage shrinks, recovery becomes vastly more challenging over time. Long-term survival is an exception, not the guiding rule.

    Humanity likes to think of itself as the result of an incredibly unique progression. Perhaps studies like these suggest that we are actually what remains when everything else disappears. The reason any of us live today comes down to a small group of ancient outlasters: persevering individuals whose genetic lines are the building blocks of every human living today.

  • Researchers capture sperm whales headbutting on camera, validating what sailors have said for centuries
    Photo credit: University of St Andrews/YouTubeSperm whales headbutting.
    ,

    Researchers capture sperm whales headbutting on camera, validating what sailors have said for centuries

    “It’s exciting to think about what as-yet unseen behaviours we may soon uncover”

    For centuries, sailors have told wild tales of whales ramming ships. Reports of a sperm whale smashing and sinking the Essex in 1820 inspired Herman Melville to write Moby-Dick. Scientists had never witnessed it themselves—until now.

    Researchers have captured the first-ever drone footage of sperm whales headbutting each other. During fieldwork off the coast of the Balearic Islands, they recorded three separate incidents between 2020 and 2022.

    Drone footage captures sperm whales headbutting

    The new study was published in the journal Marine Mammal Science. Using drones, researchers from the University of St Andrews, the University of the Azores, and Asociación Tursiops captured video evidence of sperm whales headbutting. They found that most of the whales were young, immature males. In one incident, a young male circling near a female suddenly charged and slammed into her, knocking her off course. After the impact, she broke away from the group and did not return.

    The researchers estimated impact speeds ranging from 1.8 to 8 miles per hour, with collisions generating forces of up to 20 tons of pressure. The impacts captured on video were not necessarily considered aggressive. In fact, researchers believe the behavior reflects rough play or forms of mock combat. Similar behaviors can be seen in other mammals, like dolphins and lions.

    sperm whales, Moby Dick, literature, history, whaling
    A depiction of Moby-Dick.
    Photo credit: Canva

    Observations of sperm whale behavior

    Using their large heads, sperm whales have been reported by whalers to strike and move objects since the 19th century. “It was really exciting to observe this behaviour, which we knew had been hypothesised for such a long time, but not yet documented and described systematically,” said Dr. Alec Burslem, lead author of the study.

    “It’s exciting to think about what as-yet unseen behaviours we may soon uncover, as well how more headbutting observations may help us to shed light on the functions the behaviour may serve,” Burslem added.

    Documented, unprovoked attacks on humans by sperm whales are exceedingly rare, with most occurring during historical whaling incidents. Research indicates that sperm whales do not naturally exhibit aggression toward humans. While they can be curious, they often avoid vessels and observers. Historical accounts of whales ramming ships are likely defensive reactions rather than predatory attacks.

    ocean mammals, sperm whales, non-aggressive behavior, language, social structures
    A sperm whale.
    Photo credit: Canva

    Language and cultural identities

    Whales use clicks like letters, combining them into sequences that function like words in a complex form of communication. A 2024 study found that sperm whales use a highly sophisticated communication system with structures resembling a phonetic alphabet. These audio cues are used for coordination, caregiving, and social interaction.

    A 2022 study found that specific click patterns serve as symbolic markers that help establish cultural identities within sperm whale pods. Researchers identified seven distinct clans, each with its own unique dialect. This provided quantitative evidence of whale social structures known as identity codas.

    Studying this new drone footage offers fresh insights into whale social groups and behavior. While the headbutting may look aggressive, researchers interpret it as rough play. With technologies like drones giving scientists unprecedented access to these interactions, it’s exciting to think of what discoveries are yet to be made.

  • Study reveals startling truth: Intelligence lowers our empathy toward other people
    Photo credit: Canva(L) A man gives a thumbs up; (R) An eviction notice

    A recent study conducted on adults in the UK found that people with higher cognitive ability scored lower on moral foundations. The study, published this summer in the journalIntelligence, sought to gage people’s response to the Moral Foundations Theory based on their overall intelligence. After two different studies, no difference was found between genders, but a person’s intelligence revealed a different story.

    The research suggests that analytical thinkers tend to override their baseline moral intuitiveness. But what does that actually mean? First, cognitive ability refers to problem solving, abstract thinking, memory, logic, language comprehension, and basic critical thinking. This isn’t only IQ, but a person’s ability to process and apply their knowledge. Think of it as a living scholastic aptitude test (SAT.)

    intelligence, moral psychology, cognitive science, empathy, human behavior
    Man embraces a sunset. Photo Credit: Canva

    After testing to rate cognitive ability, subjects were then tested against The Moral Foundations Theory. The idea behind the theory is that, despite different cultures and populations, people tend to follow a similar set of themes and intuitive ethics. The theory follows six core ideas: care, equality, proportionality, loyalty, authority, and purity.

    Surprisingly, the results of the tests found that people with higher intelligence found the moral foundations to be less important.

    Care

    Care has to do with the virtues of kindness, gentleness, and nurturing. This is the foundation of empathy. By feeling connected and emotionally attached to the community, people gain purpose and a strong feeling of belonging.

    Equality

    intelligence, moral psychology, cognitive science, empathy, human behavior
    Symbols for equal diversity. Photo credit: Canva

    Always a hot topic on the political playing field, equality looks to create fair circumstances. The idea is all people have equal opportunity and treatment. Communities offering equality have reduced resentment and foster a cooperative environment where people feel respected and included.

    Proportionality

    This concept is based on fairness and merit. People should get what they deserve and be treated by what they do, not just who they are. What you put in, you get out. This is a driving principle underlying a core belief of this country: that anyone can achieve most anything if they are willing to put in the work. Many would argue for its merit while others would call it wishful thinking.

    Loyalty

    intelligence, moral psychology, cognitive science, empathy, human behavior
    Hands come together. Photo credit: Canva

    This is another popular topic of political leaders and followers. We are tribal by nature and greatly benefit from a feeling of belonging. Sacrificing the individual wants for the needs of the group, this is one of the foundational cornerstones of building communities.

    Authority

    leaders, leadership, hierarchy, traditions, genetics, authority, groups, UK adults, social groups
    Leader in front of group. Photo credit: Canva

    Authority encompasses the concepts of hierarchy and respect for traditions. Research shows we are genetically programmed to seek a social hierarchy. As much as many fight to climb to the top, feeling a part of the system is often enough to supply someone with a great amount of emotional security.

    Purity

    Perhaps you’ve heard the phrase, “Your body is a temple.” The ideal is expressed through self-discipline, self-improvement, and spirituality. Striving to be noble and less carnal, people try to be the best version of themselves. The moral advancement and the elevation of the social consciousness of the community is believed to have incredible value.

    These core values are believed to be inherent in all people, but are they? At least according to this most recent study, the more intelligent you are, the less you might care about them. However, author and literary genius Leo Tolstoy once famously claimed that kindness is one sure sign of a highly intelligent person and other studies back up his views. Maybe when it comes down to it, it depends on the person.

    This article originally appeared last year. It has been updated.

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