Category: evolutionary psych

The Psychology of Sex Differences – 5 Revealing Insights From Our Primate Cousins

GettyImages-519106121.jpgBy Christian Jarrett

There are behavioural differences, on average, between the sexes – few would dispute that. Where the debate rages is over how much these differences are the result of social pressures versus being rooted in our biology (the answer often is that there is a complex interaction between the two).

For example, when differences are observed between girls and boys, such as in preferences for play, one possibility is that this is partly or wholly because of the contrasting ways that girls and boys are influenced by their peers, parents and other adults (because of the ideas they have about how the sexes ought to behave). Studying non-human primates allows us to identity sex differences in behavior that can’t be due to human culture and gender beliefs.

Learning more about the biological roots of behavioural sex differences should not be used as an excuse for harmful stereotyping or discrimination, but it can help us better understand our human nature and the part that evolved sex differences play in some of the most important issues that affect our lives, including around diversity, relationships, mental health, crime and education.

Earlier this year, as part of a special issue of the Journal of Neuroscience Research – titled “An Issue Whose Time Has Come: Sex/Gender Influences on Nervous System Function” – Elizabeth Lonsdorf at Franklin and Marshall College published a useful mini-review detailing some of the sex differences observed among monkey and ape infants and juveniles.

“Many sex differences in behavioral development exist in nonhuman primates,” she writes, “despite a comparative lack of sex-biased treatment by mothers and other social partners”. Here is a digested account of five of these behavioural sex differences:   

Continue reading “The Psychology of Sex Differences – 5 Revealing Insights From Our Primate Cousins”

Lazy bees and clean hyenas: Review finds that animals vary in trait conscientiousness

GettyImages-164307835.jpgBy Emma Young

Conscientiousness is a fundamental aspect of human personality, with higher levels associated with all kinds of benefits, from greater academic achievement and relationship stability to living for longer.  Yet it’s the only major human personality dimension not to have been widely identified in animals, which poses an evolutionary puzzle – if animals don’t show signs of conscientiousness, where did the human variety come from? But now a major review of hundreds of relevant papers, published in Psychological Bulletin, concludes that in fact, “there are many documented examples of conscientiousness behaviour in other animals”. The work also suggests that there are two main branches to conscientiousness, each associated with an evolutionary drive to solve different types of problems.

Continue reading “Lazy bees and clean hyenas: Review finds that animals vary in trait conscientiousness”

Why pink LEGO might be bad for girls (but we’re not convinced)

GettyImages-681325218.jpgBy Christian Jarrett

While the idea that the lack of women in science and tech is entirely about cultural obstacles is contentious (as demonstrated by the recent Google memo furore), few would argue that social and cultural factors aren’t important. And these social influences may begin early. For example there’s an argument that boys are encouraged to play with toys that are likely to promote skills that will help them in science and maths. Toys aimed at girls, in contrast, are more likely to promote stereotypically feminine skills, such as nurturing.

LEGO, say Megan Fulcher and Amy Hayes, the authors of a new paper in the journal Sex Roles, is a case in point: its marketing is skewed towards boys, especially since the increase in packaged sets, which tend to feature stereotypically masculine items like pirate ships and castles. The result, they argue, is that boys are more attracted to LEGO, girls deterred from it, and that boys get to practice their building skills while girls don’t.

LEGO has heard some of this criticism (and no doubt also seen a gap in the market) and they’ve released girl-friendly packaged sets and product lines, including Friends items with a focus on people and including pink bricks. But Fulcher and Hayes – who very much speak from the nurture perspective on these issues (they fail to cite a single study demonstrating a biological basis for sex differences in toy preference) – fear this could be counterproductive because girlie bricks and sets are likely to promote more stereotypically feminine LEGO play and remind girls of their gender. To find out if their concerns are justified the researchers tested the LEGO building skills and choices of 116 girls and boys (aged 5 to 10) depending on whether they were given boyish LEGO bricks and packages or girlie ones.

Continue reading “Why pink LEGO might be bad for girls (but we’re not convinced)”

Researchers are studying psychopathic chimps to better understand the human variety

GettyImages-584864828.jpgBy Emma Young

To understand the drivers of a psychopathic personality (marked by callousness, disinhibition and superficial charm), it’s worth looking at our closest relatives. Some chimps, like some people, score highly on scales designed to evaluate psychopathic tendencies. And new work in Frontiers in Neuroscience reveals a potentially important genetic contributor to psychopathic traits in chimps, which could lead to a better understanding of the traits in people.

Continue reading “Researchers are studying psychopathic chimps to better understand the human variety”

Scholars who believe nurture trumps nature also tend to doubt the scientific method

74896366_cb518860b6_z.jpgBy Christian Jarrett

How far has evolutionary thinking permeated through academia? A survey of more than 600 scholars from 22 disciplines, ranging from psychology and economics through to gender studies, sociology and the humanities, finds that there remain two distinct cultures in the academe, at least regarding views on the principal causes of human behaviour and human culture.

One group, made up of psychologists, economists, philosophers and political scientists believes more strongly in the genetic influences on behaviour, beliefs and culture. The other group, consisting sociologists, non-evolutionary anthropologists, women’s and gender studies scholars and all humanities scholars (except philosophy), believes in the primacy of environmental influences. What’s more, those scholars favouring environmental accounts also tend to be sceptical of the scientific method. The findings are published open-access in the newly launched journal Evolutionary Studies in Imaginative Culture.

Continue reading “Scholars who believe nurture trumps nature also tend to doubt the scientific method”

Attractive people have shorter relationships and are more interested in alternative partners

87th Annual Academy Awards - Arrivals
Scarlett Johansson announced her split from Romain Dauriac this January

By Christian Jarrett

You probably won’t be reaching for your violin too quickly but a series of new studies provide compelling evidence that beauty is a kind of “relationship liability”. While more physically attractive people have a clear advantage when it comes to finding partners, the results suggest that their relationships are more likely to breakdown, at least in part because they take greater interest in alternative partners, especially when dissatisfied in their current relationship.

The results add further nuance to our understanding of how physical beauty impacts people’s lives. While good-looking folk seem to enjoy many advantages in life, on average, such as higher pay, more happiness and others assuming they are friendly and intelligent, it seems there are complicating factors: jealousy is one, and this new research, published in Personal Relationships, suggests that less stability in their romantic relationships is another.

Continue reading “Attractive people have shorter relationships and are more interested in alternative partners”

Where do women look when sizing each other up?

Friends enjoying a party in nightclubBy Christian Jarrett

Studies show that when heterosexual women look at other women’s bodies, they, just like men, tend to spend a disproportionate amount of time looking at their waists, hips and breasts, as if estimating how much they will appeal to men. This is consistent with “mate selection theory” which argues, among other things, that women have evolved strategies to monitor potential love rivals. However, psychologists are interested in this topic, not only from an evolutionary perspective, but also because women who feel dissatisfied with their bodies, and who are vulnerable to developing eating disorders, may be especially pre-occupied with comparing their body against others, potentially exacerbating their anxieties.

Past research is mixed: some studies suggest women with body dissatisfaction and/or eating disorders pay disproportionate attention to the bodies of thin women, other studies suggest the opposite. A new exploratory paper in Psychological Research says hang on a minute, we don’t actually know much about how healthy, confident women behave when they look at other women, nor whether their attention is influenced by their feelings about their own bodies.

Continue reading “Where do women look when sizing each other up?”

Wardrobe malfunction – three failed attempts to replicate the finding that red increases attractiveness

By Christian Jarrett 

It’s one of the simplest, most evidence-backed pieces of advice you can give to someone who’s looking to attract a partner – wear red. Many studies, most of them involving men rating women’s appearance, have shown that wearing red clothing increases attractiveness and sex appeal. The reasons are thought to be traceable to our evolutionary past – red displays in the animal kingdom also often indicate sexual interest and availability – complemented by the cultural connotations of red with passion and sex.

But nothing, it seems, is straightforward in psychology any more. A team of Dutch and British researchers has just published three attempts to replicate the red effect in the open-access journal Evolutionary Psychology, including testing whether the effect is more pronounced in a short-term mating context, which would be consistent with the idea that red signals sexual availability. However, not only did the research not uncover an effect of mating context, all three experiments also failed to demonstrate any effect of red on attractiveness whatsoever.  Continue reading “Wardrobe malfunction – three failed attempts to replicate the finding that red increases attractiveness”

Psychologists said it’s disgusting to be reminded that you are an animal. It seems they were wrong

Woman with dog swimming underwater
By Christian Jarrett

Disgust has become a hot topic in psychology research over the last decade or so, not least because findings have shown that the way we respond to physically disgusting threats, like disease-infested blood and puss, is closely related to the way we think about moral violations and moral concepts like purity (hence people’s reluctance to don a shirt purportedly worn by Adolf Hitler).

One repeated claim in this area is that we have evolved to be disgusted by any reminder that we are animals. For instance, the leading disgust and morality researchers Jonathan Haidt, Paul Rozin and Clark McCauley have stated that disgust is “a defensive emotion that guards against the recognition of our animality” and that “anything that reminds us that we are animals elicits disgust”. It’s a compelling idea that feeds into other areas of psychology, for example related to how we react to and cope with reminders of our mortality, and the way we often instinctively dehumanise criminals, pariahs and outsiders. The trouble is, nobody has actually put the claim to a robust test. Until now.  Continue reading “Psychologists said it’s disgusting to be reminded that you are an animal. It seems they were wrong”

Even preschoolers like to gossip

Secret talk
Want a good reputation? Better impress those gossiping preschoolers

By Christian Jarrett

Gossiping is a serious business because it helps us keep track of who to trust and who to avoid. To count as proper gossip, you have to give or receive new information about a third-party. That’s effectively what’s happening when a friend begins a sentence: “You wouldn’t believe what [insert name] did the other day …” – their anecdote is giving you precious information about the reputations of the people involved. Just how early in life do we start gossiping? A new study in the British Journal of Developmental Psychology shows that in its simplest form – telling someone else who to trust – gossiping is well on its way at age three. Continue reading “Even preschoolers like to gossip”