One reason that personality is such an important psychological concept is because of what it tells us about the kind of lives we’re likely to lead. For example, if you are very conscientious then you’re more likely to enjoy good physical health and more harmonious relationships; extraverts are happier; highly neurotic people experience more mental health problems; open-minded people command higher earnings; and, just as you’d expect, more ‘agreeable’ people are also usually popular and have lots of friends.
But our personalities don’t only show themselves in our long-term success and well-being. They also correlate with the kind of things we get up to on a mundane, daily basis. A
new studypublished in Personality and Individual Differences has charted these behavioural ‘signatures’ of the Big Five personality traits – listed above – in more detail than ever before. And the results are surprising.
While it goes without saying, for instance, that extraverts are more likely to go to parties and that conscientious people are less likely to be tardy, you might not have anticipated that extraverts also spend more time luxuriating in hot tubs or that conscientiousness goes hand in hand with reading fewer books.
The researchers, Benjamin Chapman at the University of Rochester and Lewis Goldberg at the Oregon Research Institute, profiled nearly 800 people in Oregon, USA, most of whom were white, and their average age was 51. The personality test asked participants to rate how accurately
100 different trait adjectives described their personalities, including words such as bashful, kind, neat, relaxed, moody, bright and artistic. The researchers then compared these personality test scores with the same participants’ answers, recorded four years later, to how often they had performed 400 different activities over the last year, from reading a book to singing in the shower.
Extraverts tended to spend more time talking on the phone while driving, decorating, and trying to get a tan
As well as wallowing more in hot tubs, extraverts apparently spent more time planning parties, drinking in bars, discussing ways to make money, talking on the phone while driving, decorating, and trying to get a tan (though not all at once). Greater conscientiousness, in contrast, was distinguished by the avoidance of various activities, including such innocuous pastimes as reading (which Chapman and Goldberg speculated may be seen by the highly conscientious as a leisure-time luxury), swearing and chewing on a pencil.
People scoring high on agreeability, meanwhile, said they spent more time doing ironing, playing with children and washing the dishes – presumably because their strong motivation to keep other people happy means they’d rather do the chores than have domestic acrimony. More surprisingly, they were also more likely to sing in the shower or the car.
Strongly open-minded people were more likely to read poetry, eat spicy breakfasts, and lounge around in the nude
Neurotic folk, meanwhile, engaged more often in activities that are associated with helping reduce mental distress, such as taking more tranquilisers and anti-depressants. But they also admitted to more anti-social behaviours, such as losing their temper more often, or making fun of others – perhaps because they struggle to keep their own emotions in check. Finally, open-mindedness went together with some obvious behaviours like reading poetry, going to the opera, smoking marijuana and producing art, but also some less obvious, like swearing around others, eating spicy food at breakfast, or lounging around the house with no clothes on. (To be precise, the highest scorers said they were about twice as likely to have sat around in the nude for more than 15 times in the past year, compared to the lowest scorers.) They were also less likely to follow a sports team.
This study is impressive for the huge range of activities that it investigated, though it remains to be seen if the same personality-behaviour links would be found in other cultures around the world, and of course there remain many thousands of other daily behaviours to be looked at. The new findings add to earlier research on behaviour-personality links, most of which has tended to focus on more specific activities or only on certain traits. For example, previous studies had shown that
the highly conscientious are more likely to wear a watch,
comb their hair and polish their shoes; that
extraverts have more tattoos, that
introverts use more concrete language;
agreeable folk get fewer speeding tickets and
eat more sweet foods; and that
open-mindedness correlates with a penchant for fruit and vegetables,
art-house movies, and a preference for
dry, rather than sweet, white wine.
If you’re a prolific curser, you can now defend your habit as a sign of your open-mindedness
Other research has looked at behaviours, some more obvious than others, that correlate with the so-called Dark Triad personality traits of Narcissism, Machiavellianism and Psychopathy. For example, high scorers on psychopathy aren’t just more prone to violence, bullying and aggression, they also
maintain unusually long eye contact, and along with Machiavellians, are more likely to participate in and enjoy
online trolling.
There’s a serious side to this field of research – learning more about the harmful and unhealthy everyday behaviours linked to the different personality traits could contribute to better, more targeted health campaigns and interventions. Also, research into personality often involves people answering questionnaires about themselves, hopefully in an honest way. By discovering some quirky and less expected behavioural correlates of the Big Five traits, there’s the possibility of one day devising a questionnaire that asks people about the activities they engage in, without them realising they are actually revealing their personality.
Of course, there’s also a fun, thought-provoking element to the new findings – for example, if you’re a prolific curser, you can now defend your habit as being a sign of your open-mindedness. And maybe now you’ll also be a little more forgiving of your house-mate’s habit of singing in the shower. After all, it could just be another sign of his or her agreeable personality.
"The figures are just horrifying," says
Jonathan Wells, who studies childhood nutrition at University College London in the UK. "It's extremely rare for mammalian mothers to pay such a high price for offspring production."
So why exactly is childbirth so risky for humans? And is there anything we can do to further reduce those death rates?
Scientists first began thinking about the problem of human childbirth in the middle of the 20th Century. They soon came up with an idea that seemed to explain what was going on. The trouble began, they said, with the earliest members of our evolutionary lineage – the hominins.
From an early date in our prehistory, hominin babies may have had to twist and turn to pass through the birth canal
The oldest hominin fossils so far found date back about seven million years. They belong to animals that shared very few of our features, except perhaps one: some researchers think that, even at this early stage,
hominins were walking upright on two legs.
To walk on two legs efficiently, the hominin skeleton had to be pushed and pulled into a new configuration, and that affected the pelvis.
In most primates the birth canal in the pelvis is relatively straight. In hominins, it soon began to look very different. Hips became relatively narrow and the birth canal became distorted – a cylinder that varied in size and shape along its length.
Then things got even worse.
About two million years ago, our hominin ancestors began to change again. They lost their more ape-like features such as a relatively short body, long arms and small brain. Instead they began to gain more human-like ones, like
taller bodies, shorter arms and bigger brains.
That last trait in particular was bad news for female hominins.
I was going to find evidence that supported the obstetric dilemma, but very soon everything came crashing down
Big-brained adults start out life as big-brained babies, so evolution came into conflict with itself. On the one hand, female hominins had to maintain a narrow pelvis with a constricted birth canal in order to walk efficiently on two legs. But at the same time the foetuses they carried were evolving to have larger heads, which were a tighter and tighter fit through those narrow pelvises.
Childbirth became a distressingly painful and potentially lethal business, and it remains so to this day.
In 1960, an anthropologist called Sherwood Washburn gave this idea a name:
the obstetrical dilemma. It is now often called the "obstetric dilemma". Scientists thought it explained the problem of human childbirth perfectly. Many still think it does.
But some, including Wells, are no longer happy with this standard explanation. In the last five years, Wells and several other researchers have begun to push against the classic story of the obstetric dilemma.
They think Washburn's idea is too simplistic, and that all sorts of other factors also contribute to the problem of childbirth.
Holly Dunsworth of the University of Rhode Island, Kingston, was drawn to the obstetric dilemma while she was still a grad student. "I thought it was so exciting, I was going to find evidence that supported the obstetric dilemma," she says. "But very soon everything came crashing down."
We have bigger babies and longer pregnancies than you would expect
The problem was with the predictions Washburn made. "When Washburn wrote his article, he was actually saying that the obstetric dilemma was solved by giving birth to babies at a relatively early stage in their development," says Wells.
Go back to that moment two million years ago when human brains began to grow larger. Washburn suggested that humans found a solution of sorts: shortening the length of the human pregnancy. Human babies were forced out into the world earlier than they really should be, so that they were still relatively small, with diminutive, underdeveloped brains.
Washburn's explanation seems logical. Anyone who has held a newborn can appreciate how underdeveloped and vulnerable they are. The standard view is that other primates hold onto their pregnancies for longer and give birth to babies that are more developmentally advanced.
But, says Dunsworth, it is simply not true.
"We have bigger babies and longer pregnancies than you would expect," she says.
Women give birth to babies with larger brains than we would expect
In an absolute sense human pregnancies are long. They typically last 38-40 weeks, whereas a chimpanzee pregnancy is 32 weeks long, and gorillas and orang-utans give birth after about 37 weeks.
The same thing applies for brain size. Women give birth to babies with larger brains than we would expect of a primate with the average woman's body mass. This means that a key prediction of Washburn's obstetric dilemma is incorrect.
There are other problems with Washburn's idea too.
A central assumption of the obstetric dilemma is that the size and shape of the human pelvis – and the female pelvis in particular – is highly constrained by our habit of walking upright on two legs. After all, if evolution could have "solved" the problem of human childbirth by simply making women's hips a little wider and the birth canal a little larger, it surely would have done so by now.
The birth canal is extraordinarily variable in size and shape
The researchers collected metabolic data from male and female volunteers who were walking and running in the lab. Volunteers with wider hips were no more inefficient at walking and running than their narrow-hipped peers. From purely energetic considerations, at least, there does not seem to be anything stopping humans evolving wider hips that would make childbirth easier.
"The basic premise of the obstetric dilemma – that having a small or narrow pelvis is best for biomechanical efficiency – is likely not correct," says
Helen Kurki of the University of Victoria in British Columbia, Canada.
Kurki was not involved with Warrener's study, but her own research has identified yet more problems for the traditional obstetric dilemma hypothesis.
If the female pelvis really is tightly governed by two opposing forces – the need to be narrow for walking and the need to be wide for giving birth – the shape of the birth canal should vary little between women. It should be "stabilised" by natural selection.
Pregnant women sometimes joke that their developing foetus feels like an energy-sapping parasite
"I think my findings do support shifting attitudes to the obstetric dilemma," says Kurki.
Washburn's tidy narrative does not seem quite as satisfying as it once did. There has to be something else going on.
Dunsworth thinks she has identified one important missing piece in the puzzle: energy.
"We max out toward the end of pregnancy," says Dunsworth, herself a mother. "Those last weeks and months of pregnancy are tiring. They are pushing right against the possible sustainable metabolic rates in humans. It has to end at some point."
Evolution could, in principle, make the pelvis larger – but it has not had to
Pregnant women sometimes joke that their developing foetus feels like an energy-sapping parasite. In a sense it really is, and its energy demands grow with every passing day.
In particular, human brains have an almost insatiable appetite for energy. Growing a second, tiny brain inside the womb can push a pregnant woman close to the edge, metabolically speaking.
Dunsworth calls this idea
the energetics of gestation and growth (EGG) hypothesis. It suggests the timing of childbirth is governed by the difficulties of continuing to nourish a developing foetus beyond 39 weeks – not by the difficulties of squeezing the baby out through the birth canal.
Dunsworth thinks people obsess too much about the tight fit between a baby's head and its mother's birth canal. It might seem too much of a coincidence that the two are so closely size-matched, but she says the pelvis has simply evolved to be the size it needs to be. Evolution could, in principle, make the pelvis larger – but it has not had to.
For most of human evolution, childbirth might have been quite a lot easier
By and large, Kurki shares this view. "The obstetric canal is big enough, the majority of the time, for the foetus to pass through," she says.
Wells agrees. "It's impossible to imagine the problem has been this bad over the long term."
Perhaps it has not. In 2012, Wells and his colleagues took a look at the prehistory of childbirth, and came to a surprising conclusion. For most of human evolution, childbirth might have been quite a lot easier.
The prehistory of childbirth is a difficult subject to study. The hominin pelvis is rarely preserved in the fossil record, and newborn skulls are even thinner on the ground. But from the meagre evidence available it seems that some earlier species of human, including
Homo erectus and even some Neanderthals,
had a relatively easy time of it when it came to giving birth.
A shift to farming may have led to developmental changes that made childbirth far more difficult
In fact, Wells and his colleagues suspect childbirth might even have been a relatively minor problem in our species – at least to begin with. There are very few newborn baby skeletons among the human remains from early hunter-gatherer groups, which might hint that death rates among newborns were relatively low.
If there was a rise in newborn death rates at the dawn of farming, there were almost certainly several factors involved.
But Wells and his colleagues suspect a shift to farming also led to developmental changes that made childbirth far more difficult. A rise in infant mortality at the dawn of farming might be due in part to a raised risk of death during childbirth.
Human childbirth suddenly became more difficult about 10,000 years ago
There is one striking feature archaeologists have noticed when comparing the skeletons of early farmers with their hunter-gatherer ancestors.
The farmers were noticeably shorter in stature, probably because their carbohydrate-rich diet was not particularly nutritious compared to the protein-rich hunter-gatherer diet.
On top of that, the carbohydrate-rich diets that became more common with farming can cause a developing foetus to grow
larger and fatter. That makes the baby harder to deliver.
Combine these two factors and human childbirth – which might have been relatively easy for millions of years – suddenly became more difficult about 10,000 years ago.
Something rather like this "farming revolution effect" replays whenever human diets become poorly nutritious – particularly if those diets also contain a lot of carbohydrates and sugars, which encourage foetal growth.
"We can make a simple prediction that the nutritional status of mothers should be associated with a local prevalence of maternal mortality and difficulties with giving birth," says Wells.
The statistics clearly follow such a pattern, suggesting that improving nutrition might be a fairly easy way to reduce maternal mortality.
Pregnant women have adapted to nourish their foetus for as long as they can
Both Dunsworth and Kurki think that Wells has identified something significant in his work – something that perhaps would only be evident to a researcher with the right background in nutrition and development.
"I'm so lucky that Jonathan is describing these complex issues from his perspective of human health," says Dunsworth. "At the same time I'm approaching the problem from my perspective of human evolution."
So we now have a new explanation for the difficulties of human childbirth. Pregnant women have adapted to nourish their foetus for as long as they can before it grows too large to feed internally. The female pelvis has adapted to be just the right size to allow this maximally-nourished foetus to travel through safely. And dietary changes in the last few thousand years have upset this fine balance, making childbirth risky – particularly for mothers who have a poor diet.
However, Dunsworth says that is probably not the end of the story.
Washburn's ideas made good intuitive sense for decades, until Dunsworth, Wells, Kurki and others began to pick them apart. "What if the EGG perspective is too good to be true?" asks Dunsworth. "We have to keep searching and keep collecting evidence."
This is exactly what other researchers are doing.
For instance, in 2015
Barbara Fischer of the Konrad Lorenz Institute for Evolution and Cognition Research in Klosterneuburg, Austria and
Philipp Mitteroecker of the University of Vienna, Austria took another look at the female pelvis.
A woman's pelvis takes on a shape more conducive to childbirth in her late teens – when she reaches peak fertility
It seemed to them that Dunsworth's EGG hypothesis – compelling though it is – could actually be seen as complementary to Washburn's ideas, rather than disproving them entirely. Dunsworth agrees: she thinks many factors are involved in the evolution of modern childbirth.
Fischer and Mitteroecker investigated whether there is any correlation between female head size and pelvis size. Head size is heritable, at least to some extent, so women would benefit during childbirth if those with larger heads also naturally had a wider pelvis.
The researchers' analysis of 99 skeletons suggested
such a link does indeed exist. They concluded that a woman's head size and her pelvic dimensions must somehow be linked at the genetic level.
"This does not mean that the [problem of childbirth] has been resolved," says Fischer. But the problem would be even worse if there was no link between head size and pelvis width.
And there is another complication: women's bodies change as they get older.
Many babies are now born by Caesarean section
Their data suggested that a woman's pelvis takes on a shape more conducive to childbirth in her late teens – when she reaches peak fertility. It then stays that way until around her 40th birthday, when it then gradually changes shape to become less suitable for childbirth, ready for the menopause.
The scientists suggest these changes make childbirth a little easier than it otherwise would be. They call this idea the "developmental obstetric dilemma" (DOD).
"The DOD hypothesis provides a developmental explanation for the variation in pelvic obstetric dimensions," says Ponce de León.
If all these evolutionary pressures are acting on childbirth, is the process still changing and evolving even now?
In December 2016, Fischer and Mitteroecker made headlines with a theoretical paper that addressed this question.
We all either did or didn't arrive in the world through a pelvis
"We all either did or didn't arrive in the world through a pelvis," says Wells. "If we did, that pelvis mattered. And if we didn't, that in itself is interesting."
Ever since live birth evolved, babies have been constrained to some degree by the size of the birth canal. But maybe, for some babies at least, that is no longer true.
With its 26 million people, Delhi has been described as a microcosm of India, with trappings from the country’s many cultures, religions and traditions. Centuries of global trade, conquest and colonisation have made the city one of the world’s most multicultural. And residents who adapt to this ever-changing culture are embraced as fellow ‘Dilliwalas’ – the term residents often call themselves, originating from the phase ‘Dillwalo ki Dilli’, the place where the people with big hearts live.
This diversity makes it easy to find your own niche. “Delhi's vibes are a lot like the aroma of a nice coffee shop,” said Nishchal Dua from New Delhi, a territory within larger Delhi and capital of India. “You can smell multiple things the moment you enter and it's entirely up you to pick the one you like.”
Delhi's vibes are a lot like the aroma of a nice coffee shop – you can smell multiple things the moment you enter and it's entirely up you to pick the one you like
The city is the country’s political and fashion capital, giving it a vibe that evokes a blend of New York City with Washington DC, according to Anjhula Mya Singh Bais who lived in New Delhi for six years. That does mean it can be a little harder to assimilate in than in other Indian cities though. “Delhi is more about who you are, where you come from, what you are wearing or driving, so it takes time to break in,” she said.
Despite its diversity, Delhiites young and old unite over one thing: the love of a good party. Weddings here last from five to 10 days and can have as many as 1,000 guests attending the events, parties and traditional ceremonies. While weddings around the country tend to be multi-day affairs, Delhi has gained a reputation for having as many as 60,000 weddings on a single auspicious date. And weddings have grown so extravagant that lawmakers have even
put forward bills to curb excessive spending. “It's not unusual to see the groom coming to the wedding in a helicopter on D-Day,” Dua said. “I’m not kidding, my father is a pilot.”
With more than a million weddings in the city every year, these extravagant and loud parties make up a huge part of residents’ social life, but a younger, more Western scene also exists in the many clubs and restaurants. The city has a longstanding foodie culture, with diverse flavours and new spots opening up all the time. Bais suggests
The Social in Hauz Khas Village, a collaborative workspace complete with cocktails; prohibition-style bar
Public Affair; or European-inspired Civil House restaurant in Khan Market.
Where do you want to live?Expats tend to congregate in the southern side of Delhi, especially in the neighbouring city of Gurgaon (30km south-west of New Delhi), where many of the multinational businesses are located.
South Delhi, a large district within Delhi, is also considered a higher end place to live. Vasant Vihar is home to many embassies, while Golf Links (next to the Delhi Golf Club) and nearby Lodhi Road are also all considered prestigious parts of the neighbourhood.
“If you’re not one of the lucky people with an office right next to where you want to spend your free time, decide whether you want to be stuck in traffic every day to get to the office, or in the evenings and weekends getting to social activities,” advised Linn Back, an
InterNations Ambassador originally from a small town in Sweden. “I choose the latter, which is why I live in Gurgaon about 15 to 40 minutes away from my office depending on traffic, but means I’ll be stuck in traffic for at least an hour to get to a Friday night party.”
Where can you travel?Delhi is so large it is well worth exploring on its own merits. Old Delhi in particular has retained much of its history, including 350-year-old Chandni Chowk market. “Walking to the oldest markets, mosque and temples, you experience how Delhi was 100 years back,” said Komal Darira, a Delhi native and local guide for
Intrepid Travel.
Walking to the oldest markets, mosque and temples, you experience how Delhi was 100 years back
While the Taj Mahal is 240km south of Delhi, the same architect’s work can be seen in Old Delhi’s
Red Fort, constructed in 1639 as the residence of the Mughal dynasty emperors. Delhi also has a number of green spaces and impressive temples, like the 90-acre Lodhi Gardens and the 100-acre
Akshardham complex, with a 42m-high
mandir (a Hindu temple) at its centre.
The state of Rajasthan is 300km to the south-west, for those looking to explore the ‘Pink City’ of Jaipur (named for its pastel-painted avenues) or Udaipur’s extravagant, lakeside palaces. The state of Himachal Pradesh, gateway to the Himalayas, is 300km to the north. The resort town of Manali is a popular jumping-off point for skiing, climbing and rafting.
Flights to other Indian cities are frequent and affordable. Mumbai, Delhi’s ‘rival’ city, is a two-hour flight to the south-west, and coastal Goa is just a bit further for those looking for nature and beaches.
The rest of Asia is also easily accessible. “Asia is quite a distance from Sweden, but all of a sudden Hong Kong, Dubai, Kuala Lumpur are places I can go over the weekend,” Back said.
Is it affordable?Recently ranked 124 of 133 cities in the Economist Intelligence Unit’s
Cost of Living index, Delhi is much more affordable than most major cities. Housing is about 80% cheaper than a similar place in New York City, according to price comparison site
Expatistan.com, while transportation and entertainment are also about 70% less expensive in Delhi.
That said, real estate can be much more expensive than other Indian cities, with rent in Delhi as much as 50% higher than a similar place in Hyderabad or Kolkata, according to
Expatistan. Expenses tend to vary by lifestyle, with expats often spending nearly twice as much per month as locals, which can include hiring drivers and other domestic help.
But it’s easy to save elsewhere. “Cooking at home is inexpensive, and eating out at local places is cheap too,” said Pravin Tamang, general manager of
Intrepid Travel in India and 16-year resident of the city, adding that the city offers food, fashion and lifestyle perks to keep up with every taste and need. “Delhi caters to everyone,” he said.