CLOSE
Original image
ThinkStock

Proof: Babies Can Be Jerks

Original image
ThinkStock

By Lauren Hansen

It's human nature to want to hang out with people you have things in common with. ("You like chocolate-peanut-butter ice cream? So do I! Let's eat chocolate-peanut-butter ice cream together!") On the one hand, this trait is a positive one, since it helps people form social bonds. On the other, those shared interests can, at the very least, lead to the formation of cliques that exclude others for their differences. Worse yet, groups may reach the point at which they applaud when harm comes to outsiders — just think of the mean girls in high school who revel in others' pain. Researchers already knew, thanks to previous studies, that babies, like adults, had the propensity to like babies similar to them, gravitating toward those with the same taste in food or toys. But scientists wanted to examine whether the dark side of social identification was prevalent in babies as well. Do the roots of malevolent social biases take hold in infancy?

How it was tested

 
Researchers recruited 9- and- 14-month-old babies for two separate studies. First, the infants' preference for green beans or graham crackers was established. Then the babies watched a series of puppet shows that featured a graham cracker-liking puppet and a green bean-liking puppet alternately being helped and harmed by other puppets. Finally, the babies chose between the helper puppet or the harming puppet.

The outcome

 
With combined samples of more than 200 infant participants, researchers found that both age groups overwhelmingly preferred the character that helped the puppet similar to them, over the character that harmed the similar puppet. But, surprisingly, when it came to the puppets that were dissimilar to the infants, the majority of babies in both age groups opted for the character that harmed them. In fact, their preference for the harming character, in the dissimilar scenario, was just as strong as it was for the helping character in the similar scenario. When the study was conducted again, this time with the addition of a neutral puppet, researchers found that the older group responded even more robustly to the harmer puppet.

Why this might be

 
The fact that babies act this way even before they can speak suggests that social biases "are based in part on basic aspects of human social evaluation," rather than learned through interacting with others. In other words, our social biases might be more nature than nurture.

What the experts say

 
The results are disheartening, says Karen Wynn, senior author of the study and professor of psychology and cognitive science at Yale University. "I was surprised, and my liberal bleeding heart sunk like a stone when we found them actually choosing, really robustly, the puppet who punishes." Wynn says there's need for more research, however. For one, the reasons behind the babies' choices are still unknown. Also, the babies might react differently if a parent or loved one cares for the dissimilar puppet.

But in the meantime, we'll leave you with this disheartening thought: Babies are kind of evil.

More from The Week...

How Earthquakes Create Most of the World's Gold Deposits

*

The Long-Extinct Frog Being Brought Back from the Dead

*

Why Some Ancient Birds Had Four Wings

Original image
iStock
arrow
science
5 Takeaways From the Study That Found Second-Born Boys Get Into More Trouble
Original image
iStock

Researchers have tried to understand how siblings' birth order affects their competitiveness, intelligence, kindness and other personality traits for more than a century. Now, a new study [PDF] backs up what plenty of older siblings have long argued: their younger brothers are more prone to get in trouble. Here are five takeaways from the thought-provoking research.

1. SECOND-BORN SIBLINGS ARE MORE LIKELY TO GET IN SERIOUS TROUBLE.

The study focused mostly on older brother/young brother and older sister/younger brother sets of siblings. Among two brothers, the younger boys were found to be 20 to 40 percent more likely to be disciplined in school or get in trouble with the law compared to the older boys. As study co-author Joseph Doyle, an economist at MIT, told NPR, "I find the results to be remarkable that the second-born children, compared to their older siblings, are much more likely to end up in prison, much more likely to get suspended in school."

2. THE EFFECT WAS MORE PRONOUNCED FOR BOYS.

Doyle and his colleagues didn't find the same trend among second-born girls with older brothers or sisters. Boys and girls have different rates of delinquency; in this study, the average number of delinquent first-born girls in sister pairs was 54 to almost 100 percent lower than first-born boys in brother pairs. "The gaps in delinquency are smaller when we investigate the effect of being a second-born girl," they write.

3. THE RESULTS WERE SIMILAR IN DIFFERENT ENVIRONMENTS.

The researchers used birth registries in Denmark and in Florida that identified siblings so birth order could be determined. Then, they compared that data to school records, criminal databases, and medical or public health records. Despite differences in racial demographics, education levels, parental employment, and approaches to crime and punishment between the two locales, the researchers found that "second-born boys are substantially more likely to exhibit delinquency problems compared to older siblings" in both Denmark and Florida.

4. FAMILY DYNAMICS PROBABLY PLAY A PART.

Among the families studied, first-born and second-born siblings were equally healthy and achieved similar levels of education, so those factors did not play a large part in explaining the younger kids' propensity for trouble. Instead, the researchers suggest there is less maternal attention paid to second-born children. First-born children "experience their mothers' maternity leaves … both following their own births as well as following the births of the second-born." In other words, Jan Brady might have been right about her sister Marcia.

5. OTHER STUDIES HAVEN'T UNCOVERED THE SAME LINK.

Previous studies have found little connection between certain personality traits or intelligence and the order in which siblings were born. A 2013 paper suggested that "contrary to popular belief, the relationship between birth order and delinquency is spurious." When it comes to interpreting the effects of birth order, researchers are still—metaphorically, at least—fighting over the TV remote.

arrow
science
Scientists Study the Starling Invasion Unleashed on America by a Shakespeare Fan

On a warm spring day, the lawn outside the American Museum of Natural History in Manhattan gleams with European starlings. Their iridescent feathers reflect shades of green and indigo—colors that fade to dowdy brown in both sexes after the breeding season. Over the past year, high school students from different parts of the city came to this patch of grass for inspiration. "There are two trees at the corner I always tell them to look at," Julia Zichello, senior manager at the Sackler Educational Lab at the AMNH, recalls to Mental Floss. "There are holes in the trees where the starlings live, so I was always telling them to keep an eye out."

Zichello is one of several scientists leading the museum's Science Research Mentoring Program, or SRMP. After completing a year of after-school science classes at the AMNH, New York City high school students can apply to join ongoing research projects being conducted at the institution. In a recent session, Zichello collaborated with four upperclassmen from local schools to continue her work on the genetic diversity of starlings.

Before researching birds, Zichello earned her Ph.D. in primate genetics and evolution. The two subjects are more alike than they seem: Like humans, starlings in North America can be traced back to a small parent population that exploded in a relatively short amount of time. From a starting population of just 100 birds in New York City, starlings have grown into a 200-million strong flock found across North America.

Dr. Julia Zichello
Dr. Julia Zichello
©AMNH

The story of New York City's starlings began in March 1890. Central Park was just a few decades old, and the city was looking for ways to beautify it. Pharmaceutical manufacturer Eugene Schieffelin came up with the idea of filling the park with every bird mentioned in the works of William Shakespeare. This was long before naturalists coined the phrase "invasive species" to describe the plants and animals introduced to foreign ecosystems (usually by humans) where their presence often had disastrous consequences. Non-native species were viewed as a natural resource that could boost the aesthetic and cultural value of whatever new place they called home. There was even an entire organization called the American Acclimatization Society that was dedicated to shipping European flora and fauna to the New World. Schieffelin was an active member.

He chose the starling as the first bird to release in the city. It's easy to miss its literary appearance: The Bard referenced it exactly once in all his writings. In the first act of Henry IV: Part One, the King forbids his knight Hotspur from mentioning the name of Hotspur's imprisoned brother Mortimer to him. The knight schemes his way around this, saying, "I'll have a starling shall be taught to speak nothing but 'Mortimer,' and give it him to keep his anger still in motion."

Nearly three centuries after those words were first published, Schieffelin lugged 60 imported starlings to Central Park and freed them from their cages. The following year, he let loose a second of batch of 40 birds to support the fledgling population.

It wasn't immediately clear if the species would adapt to its new environment. Not every bird transplanted from Europe did: The skylark, the song thrush, and the bullfinch had all been subjects of American integration efforts that failed to take off. The Acclimatization Society had even attempted to foster a starling population in the States 15 years prior to Schieffelin's project with no luck.

Then, shortly after the second flock was released, the first sign of hope appeared. A nesting pair was spotted, not in the park the birds were meant to occupy, but across the street in the eaves of the American Museum of Natural History.

Schieffelin never got around to introducing more of Shakespeare's birds to Central Park, but the sole species in his experiment thrived. His legacy has since spread beyond Manhattan and into every corner of the continent.

The 200 million descendants of those first 100 starlings are what Zichello and her students made the focus of their research. Over the 2016-2017 school year, the group met for two hours twice a week at the same museum where that first nest was discovered. A quick stroll around the building reveals that many of Schieffelin's birds didn't travel far. But those that ventured off the island eventually spawned populations as far north as Alaska and as far south as Mexico. By sampling genetic data from starlings collected around the United States, the researchers hoped to identify how birds from various regions differed from their parent population in New York, if they differed at all.

Four student researchers at the American Museum of Natural History
Valerie Tam, KaiXin Chen, Angela Lobel and Jade Thompson (pictured left to right)
(©AMNH/R. Mickens)

There are two main reasons that North American starlings are appealing study subjects. The first has to do with the founder effect. This occurs when a small group of individual specimens breaks off from the greater population, resulting in a loss of genetic diversity. Because the group of imported American starlings ballooned to such great numbers in a short amount of time, it would make sense for the genetic variation to remain low. That's what Zichello's team set out to investigate. "In my mind, it feels like a little accidental evolutionary experiment," she says.

The second reason is their impact as an invasive species. Like many animals thrown into environments where they don't belong, starlings have become a nuisance. They compete with native birds for resources, tear through farmers' crops, and spread disease through droppings. What's most concerning is the threat they pose to aircraft. In 1960, a plane flying from Boston sucked a thick flock of starlings called a murmuration into three of its four engines. The resulting crash killed 62 people and remains the deadliest bird-related plane accident to date.

Today airports cull starlings on the premises to avoid similar tragedies. Most of the birds are disposed of, but some specimens are sent to institutions like AMNH. Whenever a delivery of dead birds arrived, it was the students' responsibility to prep them for DNA analysis. "Some of them were injured, and some of their skulls were damaged," Valerie Tam, a senior at NEST+m High School in Manhattan, tells Mental Floss. "Some were shot, so we had to sew their insides back in."

Before enrolling in SRMP, most of the students' experiences with science were limited to their high school classrooms. At the museum they had the chance to see the subject's dirty side. "It's really different from what I learned from textbooks. Usually books only show you the theory and the conclusion, but this project made me experience going through the process," says Kai Chen, also a senior at NEST+m.

After analyzing data from specimens in the lab, an online database, and the research of previous SRMP students, the group's hypothesis was proven correct: Starlings in North America do lack the genetic diversity of their European cousins. With so little time to adapt to their new surroundings, the variation between two starlings living on opposite coasts could be less than that between the two birds that shared a nest at the Natural History Museum 130 years ago.

Students label samples in the lab.
Valerie Tam, Jade Thompson, KaiXin Chen and Angela Lobel (pictured left to right) label samples with Dr. Julia Zichello.
©AMNH/C. Chesek

Seeing how one species responds to bottlenecking and rapid expansion can provide important insight into species facing similar conditions. "There are other populations that are the same way, so I think this data can help [scientists],” Art and Design High School senior Jade Thompson says. But the students didn't need to think too broadly to understand why the animal was worth studying. "They do affect cities when they're searching for shelter," Academy of American Studies junior Angela Lobel says. “They can dig into buildings and damage them, so they're relevant to our actual homes as well.”

The four students presented their findings at the museum's student research colloquium—an annual event where participants across SRMP are invited to share their work from the year. Following their graduation from the program, the four young women will either be returning to high school or attending college for the first time.

Zichello, meanwhile, will continue where she left off with a new batch of students in the fall. Next season she hopes to expand her scope by analyzing older specimens in the museum's collections and obtaining bird DNA samples from England, the country the New York City starlings came from. Though the direction of the research may shift, she wants the subject to remain the same. "I really want [students] to experience the whole organism—something that's living around them, not just DNA from a species in a far-away place." she says. "I want to give them the picture that evolution is happening all around us, even in urban environments that they may not expect."

SECTIONS

More from mental floss studios