It's possible to tell whether someone's wealthy or not just by looking at their face, psychology researchers say.
A new paper out of the University of Toronto has found people can reliably tell if someone is richer or poorer than average by looking at a "neutral" face, without any expression.
People also use those impressions in biased ways, such as judging the rich faces more likely than the poor ones to be hired for a job.
"It indicates that something as subtle as the signals in your face about your social class can actually then perpetuate it," said study author and PhD candidate Thora Bjornsdottir.
"Those first impressions can become a sort of self-fulfilling prophesy. It's going to influence your interactions, and the opportunities you have."
Just as interestingly, the researchers found the ability to read a person's social class only applied to their neutral face and not when people are smiling or expressing emotions.
Published in the Journal of Personality and Social Psychology, the study grouped student volunteers into those with total family incomes under NZD$64,000 or above $107,000 and then had them pose for photos with neutral faces devoid of expression.
They then asked a separate group of participants to look at the photos and, using nothing but their gut instinct, decide which ones were "rich or poor" just by looking at the faces.
They were able to determine which student belonged to the rich or poor group with about 53 per cent accuracy, a level that exceeded random chance.
Their conclusion was that emotions masked life-long habits of expression that became etched on a person's face, even by their late teens or early adulthood, such as frequent happiness, which was stereotypically associated with being wealthy and satisfied.
"Over time, your face comes to permanently reflect and reveal your experiences," co-author Associate Professor Nicholas Rule said.
"Even when we think we're not expressing something, relics of those emotions are still there."
The science of 'bubble-phobia'
Some people experience intense aversion and anxiety when they see clusters of roughly circular shapes, such as the bubbles in a cup of coffee or the holes in a sponge.
Now UK psychologists have found that the condition, known as trypophobia, may be an exaggerated response linked to deep-seated anxiety about parasites and infectious disease.
Previous explanations for the condition include the suggestion that people are evolutionarily predisposed to respond to clusters of round shapes because these shapes are also found on poisonous animals, like some snakes and the blue-ringed octopus.
Now new research, led by Tom Kupfer of the University of Kent's School of Psychology, suggests that the condition may instead be related to an evolutionary history of infectious disease and parasitism that leads to an exaggerated sensitivity to round shapes.
The team noted that many infectious diseases result in clusters of round shapes on the skin, such as smallpox, measles, rubella, typhus and scarlet fever.
Similarly, many ectoparasites, like scabies, ticks and botfly also lead to clusters of round shapes on the skin.
The study saw over 300 people recruited to take part from trypophobia support groups, along with a comparison group of around 300 university students without trypophobia.
Both groups were invited to view sixteen cluster images, half showing diseased body parts the other half featuring less unpleasant scenes like drilled holes in a brick wall.
While all found the body part images repulsive, the control group wasn't bothered by the neutral images and the trypophobic group found them extremely unpleasant.
The finding supported the suggestion that individuals with trypophobia experience an overgeneralised response - to the extent that even an image of bubbles on a cup of coffee can trigger aversion in the same way as a cluster of ticks or lesions.
Our smallest star?
Astronomers at the University of Cambridge have discovered the smallest star yet measured, with a size just a sliver larger than that of Saturn.
The star is likely as small as stars can possibly become, as it has just enough mass to enable the fusion of hydrogen nuclei into helium.
If it were any smaller, the pressure at the centre of the star would no longer be sufficient to enable this process to take place.
Hydrogen fusion is also what powers the Sun, and scientists are attempting to replicate it as a powerful energy source here on Earth.
These very small and dim stars are also the best possible candidates for detecting Earth-sized planets which can have liquid water on their surfaces, such as TRAPPIST-1, an ultracool dwarf surrounded by seven temperate Earth-sized worlds.
The newly-measured star, called EBLM J0555-57Ab, is located about 600 light years away.
Part of a binary system, it was identified as it passed in front of its much larger companion, a method which is usually used to detect planets, not stars.
"Our discovery reveals how small stars can be," study lead author Alexander Boetticher said.
"Had this star formed with only a slightly lower mass, the fusion reaction of hydrogen in its core could not be sustained, and the star would instead have transformed into a brown dwarf."