Children raised near greener areas have higher IQs, study finds

Spending time in green spaces seems to yield many health benefits, most of which researchers are only beginning to understand.

crowd of people in a park
  • The longitudinal study examined the development of pairs of twins growing up in various parts of Belgium.
  • The results revealed a positive relationship between growing up near greener spaces and having a higher IQ.
  • The differences were especially significant on the lower end of the intelligence spectrum, suggesting that policy changes could make a significant difference in intellectual development.

The United Nations projects that 68 percent of the world's population will live in cities by 2050. That has some researchers worried. After all, studies show that urbanites are more likely to have psychiatric disorders, lower happiness, sleep problems, and cardiovascular and respiratory problems due to pollution, to name a few issues.

One key factor that distinguishes urban from suburban and rural environments is green space. Studies show that spending time outdoors in green spaces can decrease conditions like stress, anxiety, and depression, and also boost performance on tests related to cognitive performance and attention span.

A new study suggests that growing up in environments with more green space — even urban environments with parks — may boost intelligence and lower problematic behavior.

Intelligence is shown in association with green space in a 3,000-m radius around the current residence in twins living in an urban (n = 232), suburban (n = 126), and a rural area (n = 254)

Bijnens et al.

In the study, published in PLoS Medicine, researchers examined the development of 310 pairs of twins between the ages 10 and 15 living in Belgium. Using satellite imagery, the researchers measured the amount of green spaces near the homes of the twins, which were located in rural, suburban, or urban environments. The researchers then compared the proximity to green spaces with intelligence, and also adjusted for factors like sex, age, and neighborhood household income.

The results revealed a significant positive correlation: An increase of 3.6 percent in green space was associated with an IQ boost of 2.6 points, and a decrease of 2 points on the Achenbach Child Behavior Checklist, which measures behavioral problems.

What's more, children raised in low-green environments were more likely to have an IQ below 80. Similarly, while 11.9 percent of kids raised in a green environment had an IQ in the superior range, only 4.2 percent of kids raised in low-green environments tested in this range.

It's not completely clear what explains these findings, but the study notes that previous research has revealed:

  • Relationships between noise and air pollution and diminished cognitive development
  • Green spaces can promote physical activity and stress reduction
  • City parks may also promote social connection
two people sitting on rock overlooking


To be sure, the study only established a statistically significant correlation—it didn't conclude that a lack of green space causes lowered intelligence in children. Still, the researchers said their findings contribute to the growing body of research on the health risks of city living, and how green spaces factor into the mix.

"There is more and more evidence that green surroundings are associated with our cognitive function, such as memory skills and attention," Tim Nawrot, a professor of environmental epidemiology at Hasselt University in Belgium, told The Guardian.

"What this study adds with IQ is a harder, well-established clinical measure. I think city builders or urban planners should prioritise investment in green spaces because it is really of value to create an optimal environment for children to develop their full potential."

Massive 'Darth Vader' isopod found lurking in the Indian Ocean

The father of all giant sea bugs was recently discovered off the coast of Java.

A close up of Bathynomus raksasa

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  • A new species of isopod with a resemblance to a certain Sith lord was just discovered.
  • It is the first known giant isopod from the Indian Ocean.
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Astronomers find more than 100,000 "stellar nurseries"

Every star we can see, including our sun, was born in one of these violent clouds.

Credit: NASA / ESA via Getty Images
Surprising Science

This article was originally published on our sister site, Freethink.

An international team of astronomers has conducted the biggest survey of stellar nurseries to date, charting more than 100,000 star-birthing regions across our corner of the universe.

Stellar nurseries: Outer space is filled with clouds of dust and gas called nebulae. In some of these nebulae, gravity will pull the dust and gas into clumps that eventually get so big, they collapse on themselves — and a star is born.

These star-birthing nebulae are known as stellar nurseries.

The challenge: Stars are a key part of the universe — they lead to the formation of planets and produce the elements needed to create life as we know it. A better understanding of stars, then, means a better understanding of the universe — but there's still a lot we don't know about star formation.

This is partly because it's hard to see what's going on in stellar nurseries — the clouds of dust obscure optical telescopes' view — and also because there are just so many of them that it's hard to know what the average nursery is like.

The survey: The astronomers conducted their survey of stellar nurseries using the massive ALMA telescope array in Chile. Because ALMA is a radio telescope, it captures the radio waves emanating from celestial objects, rather than the light.

"The new thing ... is that we can use ALMA to take pictures of many galaxies, and these pictures are as sharp and detailed as those taken by optical telescopes," Jiayi Sun, an Ohio State University (OSU) researcher, said in a press release.

"This just hasn't been possible before."

Over the course of the five-year survey, the group was able to chart more than 100,000 stellar nurseries across more than 90 nearby galaxies, expanding the amount of available data on the celestial objects tenfold, according to OSU researcher Adam Leroy.

New insights: The survey is already yielding new insights into stellar nurseries, including the fact that they appear to be more diverse than previously thought.

"For a long time, conventional wisdom among astronomers was that all stellar nurseries looked more or less the same," Sun said. "But with this survey we can see that this is really not the case."

"While there are some similarities, the nature and appearance of these nurseries change within and among galaxies," he continued, "just like cities or trees may vary in important ways as you go from place to place across the world."

Astronomers have also learned from the survey that stellar nurseries aren't particularly efficient at producing stars and tend to live for only 10 to 30 million years, which isn't very long on a universal scale.

Looking ahead: Data from the survey is now publicly available, so expect to see other researchers using it to make their own observations about stellar nurseries in the future.

"We have an incredible dataset here that will continue to be useful," Leroy said. "This is really a new view of galaxies and we expect to be learning from it for years to come."

Protecting space stations from deadly space debris

Tiny specks of space debris can move faster than bullets and cause way more damage. Cleaning it up is imperative.

  • NASA estimates that more than 500,000 pieces of space trash larger than a marble are currently in orbit. Estimates exceed 128 million pieces when factoring in smaller pieces from collisions. At 17,500 MPH, even a paint chip can cause serious damage.
  • To prevent this untrackable space debris from taking out satellites and putting astronauts in danger, scientists have been working on ways to retrieve large objects before they collide and create more problems.
  • The team at Clearspace, in collaboration with the European Space Agency, is on a mission to capture one such object using an autonomous spacecraft with claw-like arms. It's an expensive and very tricky mission, but one that could have a major impact on the future of space exploration.

This is the first episode of Just Might Work, an original series by Freethink, focused on surprising solutions to our biggest problems.

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