As any parent knows, babies aren't born with a fear of heights. In fact, infants can act frighteningly bold around the edge of a bed or a changing table.
But at around 9 months, babies become more wary of such drop-offs. New research suggests infants build an avoidance of heights once they get more experience crawling and navigating the world on their own.
In one of their experiments, a group of scientists from the University of California, Berkeley, and Doshisha University in Kyoto studied babies that had not yet begun to crawl. Over the course of 15 days, some of the infants were trained to use a motorized baby go-cart that they could control.
After this period, the researchers watched how the babies reacted when they were held over a glass-covered edge. The infants who had experience with the go-cart got skittish around this virtual cliff. Their heart rates sped up, while the heart rates of the babies without the driving lessons remained steady, the scientists found.
The researchers also tested how these babies reacted to a so-called moving room, an enclosure where the walls move backwards and make whoever is inside feel like he or she is moving forward. The babies who had learned how to use a go-cart were more upset by this illusion.
In another part of the experiment, the researchers tested babies who had already started to crawl. The ones who were most upset by the moving room were also more afraid to crawl over a glass-covered virtual edge, even as their mothers encouraged them from the other side, as video from the experiment shows.
This finding suggests that as infants gain locomotor experience (in this case, crawling or navigating a go-cart), they come to rely more on visual information to help them move though an environment. The results also indicate that a fear of heights is not likely a hard-wired developmental change, but rather a shift that depends on experience, the researchers say.
An avoidance of heights has an obvious advantage: It keeps infants from falling and getting injured. So why doesn't it kick in before babies start crawling?
"One major benefit of such a delay is that infants are more prone to explore their environment and the movement possibilities afforded by that environment when they are less concerned about the consequences of their actions," the researchers write in the journal Psychological Science.
This lack of fear helps them develop movement strategies and learn how to navigate different types of surfaces, the scientists say.
"Paradoxically, a tendency to explore risky situations may be one of the driving forces behind skill development," the researchers add.
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Their Baby Cuteness Doesn't Predict Adult Attractiveness
A study published in the journal <em>Infant Behavior & Development</em> revealed that the standard "<a href="http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCQQtwIwAA&url=http%3A%2F%2Fwww.youtube.com%2Fwatch?v%3DXTV8bOv3Jhs&ei=0uLBToKrMuPu0gHkmNH0BA&usg=AFQjCNFtutJJhlTFZJ2fm-cmsDo46XMpzw" target="_hplink">You Must Have Been a Beautiful Baby</a>" has little to do with reality. When 253 college students were asked to rank photos of the same individuals as infants and young adults (without being told who was who), there was <a href="http://bodyodd.msnbc.msn.com/_news/2011/08/31/7542626-must-have-been-a-beautiful-baby-maybe-not" target="_hplink">no relationship between how cute the students found the babies and how attractive they found the grown-ups</a>.
They're Good At Sharing
No, really, it's true. It doesn't matter how many times you've heard the shout "Mine!" -- research shows babies can sense fairness at 15 months. During one study at the <a href="http://www.washington.edu/news/articles/babies-show-sense-of-fairness-altruism-as-early-as-15-months-1" target="_hplink">University of Washington</a>, 47 babies observed videos of an experimenter distributing milk and crackers to two people. When one recipient received more food than the other, the babies paid more attention. That means they had expected a fair distribution. The researchers also found that babies who did notice unfairness were more likely to share their own toys.
They Read Minds
OK, so they're not exactly psychic. But a <a href="http://www.sciencedaily.com/releases/2011/11/111101130204.htm" target="_hplink">recent study</a> from the University of Missouri found that babies just 10 months old are starting to follow the thought processes of others. Yuyan Luo, an associate professor of developmental psychology who conducted the study, tells The Huffington Post, "Babies, like adults, when they see something for the first time -- when something is surprising -- they look for a long time. It shows [they recognize] something is inconsistent." It's called the "violation of expectation," she explained. When babies are surprised by something or notice something unexpected has happened, they tend to gaze at that thing longer. In Luo's research, babies watched actors consistently choose object A (such as a block or a cylinder) over object B. When an actor then switched to object B, the babies stared for about five to six seconds longer, meaning they recognized the change in preference.
They're A Little Bit Racist
Don't judge a book by its cover. Treat all people the same. We're all equals. These are sentiments parents strive to teach their kids from a very young age. And they should. Starting, like, immediately. Researchers at the University of Sheffield in the United Kingdom found that babies at three months <a href="http://www.world-science.net/exclusives/060212_racefrm2.htm" target="_hplink">begin showing a preference for the faces of people of their own race</a>. But not all hope for equality is lost. The same study showed that babies who are exposed to people of all different races are less likely to develop bias at such an early age.
The Rhythm Is Gonna Get Them
Researchers from Brigham Young University found that five-month-old babies can <a href=" http://news.byu.edu/archive08-oct-babymusic.aspx" target="_hplink">identify an upbeat song as being different from a series of sad, slow songs</a>. In other words, they are happy. They know it. They will clap their hands. Or stare longer, as the case may be. The experimenters showed babies an emotionless face while music played. When they played a new sad song, the babies looked away. When the music pepped up, the babies stared for three to four seconds longer.
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