Philippa Kaur

Human delivers an unusually clear picture of Homo sapiens as a species shaped by climate, animals, plants, other hominins and the interactions of its own nomadic groups. Bethan Ackerley is enthralled More

Beekman suggests the complexity of childcare drove language’s spreadShutterstock/Artem Varnitsin
The Origin of LanguageMadeleine Beekman (Simon & Schuster)
Language is one of the few faculties that still seems to be uniquely human. Other animals, like chimpanzees and songbirds, have developed elaborate communication systems, but none appears to convey such a range and depth of meaning as ours. So how and why did our ancestors first develop language?
Evolutionary biologist Madeleine Beekman has spent much of her career studying insects, especially bees. In her first book for a non-specialist audience, she branches out in a big way to propose an explanation for the evolution of human language.
Her idea is that it evolved out of necessity, to enable us to cope with the demands of childcare. Compared with other mammals, human infants are exceptionally underdeveloped at birth, needing 24-hour care.
Following in the footsteps of decades of palaeoanthropological research, Beekman links helpless babies to two features of human bodies: bipedality and large brains. “As our skeletons adjusted to walking upright, our hips became narrower,” she writes. Later, our brains also expanded. “Babies with a large head and mothers with narrow hips do not make a good combination,” Beekman observes, drily.
To get around this “obstetrical dilemma”, babies are born early, before their heads get too big to squeeze through the birth canal. This enables humans to give birth relatively safely, at the cost of months spent caring for vulnerable infants.
So far, so familiar. Beekman’s big leap is her proposal that the demands of looking after human babies drove the evolution of complex language. “Taking care of human infants is so singularly difficult that evolution had to craft a completely new tool to aid the effort,” she writes, and “the design fault that started the problem in the first place also provided its solution”. Our brains made birth harder, but they also enabled us to evolve a capacity for rich and flexible language.
In proposing this idea, Beekman is wading into a very crowded marketplace. Many scenarios have been put forward for the evolution of language. Some say it developed in concert with technologies like stone tools: as we created more advanced tools, we needed more descriptive language to teach others how to make and use them. Or maybe language was a means of showing off, including through witty wordplay and insults. Then again, it might have allowed individuals to organise their own thoughts, and was only secondarily used to communicate with others.
One appealing aspect of Beekman’s proposal is that it places women and children at the centre. Because science has traditionally been skewed towards the male, ideas about human evolution tended to overly focus on them (“Man the Hunter” and all that), despite the fact that some of the most dramatic changes in our evolution involved pregnancy.

The author argues that language is only around 100,000 years old and is unique to our species

It is good to consider the roles of women and children in the origin of language. However, this doesn’t necessarily mean that Beekman is right. She marshals intriguing evidence, notably that all large-brained birds, including parrots and New Caledonian crows, produce under-cooked offspring. Why? A 2023 study showed that the strongest predictor of brain size in birds was the amount of parental provisioning.
This all sounds distinctly human-like and in line with Beekman’s narrative. But the biggest issue is timing. Humans have been bipedal for at least 6 million years and our brains grew rapidly from 2 million years ago. When, in this timespan, did childbirth become really difficult, and when did language evolve?
Beekman argues that language is only around 100,000 years old and is unique to our species. She cites a 2020 study identifying “unique gene regulatory networks that affect the anatomical structures needed for the production of precise words”. These networks are apparently only present in our species, suggesting other hominins like Neanderthals couldn’t speak as well as humans.
Beekman says this “nails it”, but other researchers have found evidence suggesting complex speech may have existed in other hominins. The evolution of human childbirth is equally tangled and uncertain. In short: nice idea, needs more evidence.
Michael Marshall is a writer based in Devon, UK

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Ferran Traite Soler/Getty Images
“I’ve always prided myself on my can-do attitude,” a reader told me this month. “Recently, however, I’ve started to feel resentful of the amount of work my boss puts at my door compared to colleagues. The more I do, the more he seems to expect of me, and I now feel that I’m cracking under the stress.”
Our reader’s frustration is surely justified. A good work ethic should be one of the most highly prized – and rewarded – qualities in an employee. Everyday experience, though, reveals this is rarely the case. Indeed, according to studies by Matthew Stanley at the National University of Singapore and his colleagues, a pernicious bias can lead managers to exploit the very people they should be prizing.
In one experiment, a group of managers were asked to read about a fictional employee named John, whose company was facing financial difficulties. They had to decide how willing they would be to give John extra hours and responsibilities without any extra pay. The researchers found that the managers were far more willing to do so if they learned that John had proved to be a loyal member of the team – compared with someone who was known to be more detached from their work.
Further studies confirmed that small displays of loyalty encouraged managers to take this attitude: the more “John” gives, the more his managers will take. As Stanley and his co-authors note, this could create a “vicious cycle” of suffering – while less loyal workers manage to escape the sacrifices. But before you start viewing your boss too harshly, it is worth noting that Stanley and his colleagues don’t believe that the managers are conscious of their behaviour, instead regarding this as a form of “ethical blindness”.
This may be compounded by the fact that many of us struggle to turn down extra responsibilities for fear of seeming disagreeable. If we are to break free from that pattern of behaviour, we need to learn how to say no. Research by Vanessa Bohns at Cornell University in New York state suggests it is easier to do so by email than in voice-to-voice or face-to-face conversations. If the request comes in person, or on the phone, I have found that it helps to ask whether you can check your schedule before agreeing. That small delay should prevent a knee-jerk “yes”, and if you want to refuse, it gives you time to formulate a polite response. Try to use assertive language. Saying “I don’t have time” is more persuasive than “I can’t make time”, for example, since it is simply reflecting the reality of your situation, rather than apologising for your inability to create more hours in the day.
But I can’t help think the onus should be on our managers to change their behaviour. A little self-awareness about their tendency to exploit their hardest workers might lead them to rethink how they reward that loyalty.

Vanessa Bohns’s book You Have More Influence Than You Think (W. W. Norton) explores the psychology and ethics of compliance, including many strategies to become more assertive.

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David Robson is an award-winning science writer and author of The Laws of Connection: 13 social strategies that will transform your life

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Elaine Knox
When I was growing up, it was customary for children to join the scouts once they reached fifth grade, around the age of 9 or 10. My parents bought me the scout uniform with the matching scarf and leather loop to fasten it around the collar, and I still remember feeling special and grown-up as I wore the uniform to the local scouts chapter.
We all formed a circle, sitting cross-legged on the ground as the group leader sat on a small stool and addressed us very seriously. When he finished talking about what it meant to be a junior scout, he told us to stand to attention as he recited the scouting pledge, and we repeated it solemnly after him.

As I said the words out loud, I knew for the first time that I was different. While the other kids seemed awed by this initiation – by the sacred bond forged with their fellow inductees and all those who had come before them – I felt nothing. They were just words.
Most people find it hard to imagine what it is like to not feel any particular affinity or loyalty towards any group. This is so unusual that it is understood by some as a psychological problem to be treated. However, over my 40 years as a clinical psychiatrist I have realised that for many of my patients (and for me) disinterest in group membership and assimilation isn’t a psychological problem – it is simply a personality type that hasn’t been recognised before.
Otroverts is the term I use for those who don’t feel the obligation to merge their identities with others. We are all born as otroverts, before the cultural conditioning of childhood cements our affiliations with various identities and groups.
Being unable to adopt a group identity can have social consequences in a culture that is designed for joining. However, it can also be quite advantageous. When you don’t belong to any group, you aren’t subject to the group’s implicit rules or swayed by its influence. This confers two beneficial traits: originality and emotional independence.
Being outside the hive, so to speak, allows you to think and create freely: to come up with unique ideas, untainted by groupthink or by what has come before. Able to distinguish between the gravitational pull of the group consensus and your own inner, personal centre of gravity, you are free to think whatever you want and to be flexible when situations change, without fear of subverting collective notions about what makes an idea “good”.
Given that you can’t be cast out of a group to which you don’t belong, you have no fear of such social rejection. You don’t seek external validation, nor do you rely on others for emotional support. You don’t feel the need to convince anyone of anything, least of all your own worth.

Our communal society often conflates belonging with connection. However, while it is true that people who struggle to connect might find it hard to achieve a sense of belonging, it isn’t true that not belonging means no connections at all. In fact, without the noise of popular culture, gossip, family conflicts or political tribes (all disinteresting to otroverts), you are free to focus on deepening bonds with the people you feel genuinely close to.
History is full of independent thinkers who aren’t emotionally dependent on any group and can therefore see the fanaticism of a hive mind long before most people do: George Orwell comes to mind.
Sadly, it often seems that people need to emerge from the ashes of self-destructive groupthink before they realise that individual thinkers can be right.
Perhaps we can learn from otroverts that, while there are many reasons to praise community, we should also be acutely aware of its darker side – tribalism.
Rami Kaminski is a psychiatrist and author of The Gift of Not Belonging

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A model of an Australopithecus homininCredit: Cro Magnon/Alamy
Thirteen hominin teeth have been discovered in Ethiopia in layers of volcanic ash between 2.6 and 2.8 million years old. The researchers think some of the teeth belong to one of the earliest members of the Homo genus, while others appear to be from a new hominin, suggesting both species lived alongside each other.
“They either shared resources, and everything was hunky-dory, or maybe one of them was marginalised,” says Kaye Reed at Arizona State University. “We just don’t know at this point.”

Previous discoveries show that before around 3 million years ago, several species of early hominins in the genus Australopithecus lived in this region, including Australopithecus afarensis, the species to which the famous Lucy fossil belonged.
From around 2.5 million years ago, the first hominins from the genus Homo start appearing, with features more similar to those of modern humans. So what happened in between? To find out, Reed and her colleagues have been digging in an area called Ledi-Geraru, where there are volcanic deposits from this crucial time.
In 2013, her team found a 2.8-million-year-old jaw that appears to be from a Homo species, pushing back the origin of this genus. Now her team has found 13 teeth in three different layers of ash.

The teeth in the oldest and the youngest layers – which are dated to 2.79 and 2.59 million years ago – also belong to the genus Homo, according to the team. But they think the teeth in the middle layer – which is dated to 2.63 million years – are from an Australopithecus. The sites are all within a kilometre of each other.
“We were expecting to find more of our genus Homo, and then we found Australopithecus as well,” says Reed.
Molar teeth from Ledi-Geraru, which may come from an unknown species of AustralopithecusBrian Villmoare: University of Nevada Las Vegas
What’s more, the Australopithecus teeth are different enough from those of A. afarensis and other australopithecines that the team thinks it is probably a new species. If they are right, it means the evolutionary tree leading to modern humans is bushier and more complex than we thought.
It is a great discovery, says John Hawks at the University of Wisconsin–Madison, but it is hard to draw conclusions based on a few teeth.
“When you find evidence that spans 200,000 years, as these teeth do, you can’t be sure that they lived at the same time,” says Hawks. “That’s a huge amount of time.”

The identification of the teeth as separate species is also questionable. “Many fossils that we find combine features that are sometimes found in different species. You can always take a small sample and break it up into the most Homo-like and most Australopithecus-like,” says Hawks.
“The question is what, statistically, you can say, and in this case the statistics on size measurements don’t show that the teeth are very different from each other. They’re in the range of overlap of early Australopithecus species and early Homo species.”

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