Kiss and tell: study says saliva sharing a signal for babies learning about relationships
When two people share a kiss or one offers the other a bite of a bagel (during non-pandemic times) there’s likely not too much thought given to the fact that they’re swapping saliva.
After all, smooching and snack sharing are everyday, intimate behaviours that occur in nuclear families and close relationships.
However, new research shows that for babies and toddlers, interactions specifically involving saliva exchange serve as a cue about social attachments and who they can count on.
Young children expect people who share saliva to have close, distinctive relationships and “to respond to one another in distress,” according to a study published Thursday in the journal Science.
The findings suggest that babies can use these cues to try to figure out early in life who around them is most likely to offer help, and which relationships are close, the researchers said in a news release.
“People have hypothesized that infants may be able to do something like this for a really long time,” said first author Ashley J. Thomas, a postdoctoral fellow at the Massachusetts Institute of Technology (MIT) in the brain and cognitive sciences department.
“How babies possibly learn about something as complex as the social world is a really old question that anthropologists have actually been asking,” Johnson said in a phone interview with CTV News, as she discussed the findings, which are novel in the field of developmental psychology.
The researchers studied the reactions of more than 150 young children, mostly in the United States, who took part in several experiments to see “if they do infer that two individuals who share saliva are likely to be in a thick relationship."
“‘Thick,’ in this case refers to a relationship that features high levels of attachment, for example, the types of intimate connections that lead to people kissing, sharing food and utensils, and, as a result, saliva.
EXPERIMENTAL PUPPET THEATRE
To answer their questions, the researchers observed toddlers and babies as they watched human actors and furry puppets interact via video chat.
In one set of experiments, the small children watched one puppet eat from the same orange slice as one actor, and play ball with a second actor.
Then, the puppet sat between the two people and showed signs of distress.
Based on earlier studies involving monkeys, the researchers theorized the babies would first look at the person whom they expected would help the distressed puppet, because in the monkey study, when the baby monkey cried, other members of the troop looked to the baby’s mother as if expecting her to respond.
Sure enough, the team from MIT found the toddlers and infants “looked first and longer” at the actor who had shared food with the puppet, expecting her to help with its distress, rather than looking at the actor who had shared a toy with the puppet.
Another set of experiments focused more specifically on saliva and involved an actor placing a finger into her mouth and then into the mouth of a puppet, or placing her finger on her forehead and then on the forehead of the puppet.
When the actor, this time standing between two puppets expressed distress, the children were again more likely to look toward the puppet that had engaged in saliva sharing.
The researchers suggest “young humans” may make use of the saliva-swapping behaviours they observe to help them understand the concept of a family structure.
But Thomas doesn’t want anyone to conclude that someone who has a “thin” relationship with a child, such as a daycare educator, is any less capable of taking care of them.
“My child’s daycare teachers are amazing. So I wouldn't expect that those daycare teachers would want to swap saliva with my daughter, but I also wouldn't expect them to have a long and enduring attachment with her,” Thomas explained.
“The idea is that basically both of those types of relationships, the ones that are friendly and cooperative, that don't involve these long and enduring attachments, and the ones that do, are both really important for humans,” she said.
However, if you can distinguish one from the other, she summed up, then you know what to expect.
CTVNews.ca Top Stories
More than 115 cases of eye damage reported in Ontario after solar eclipse
More than 115 people who viewed the solar eclipse in Ontario earlier this month experienced eye damage after the event, according to eye doctors in the province.
Toxic testing standoff: Family leaves house over air quality
A Sherwood Park family says their new house is uninhabitable. The McNaughton's say they were forced to leave the house after living there for only a week because contaminants inside made it difficult to breathe.
Decoy bear used to catch man who illegally killed a grizzly, B.C. conservation officers say
A man has been handed a lengthy hunting ban and fined thousands of dollars for illegally killing a grizzly bear, B.C. conservation officers say.
B.C. seeks ban on public drug use, dialing back decriminalization
The B.C. NDP has asked the federal government to recriminalize public drug use, marking a major shift in the province's approach to addressing the deadly overdose crisis.
OPP responds to apparent video of officer supporting anti-Trudeau government protestors
The Ontario Provincial Police (OPP) says it's investigating an interaction between a uniformed officer and anti-Trudeau government protestors after a video circulated on social media.
An emergency slide falls off a Delta Air Lines plane, forcing pilots to return to JFK in New York
An emergency slide fell off a Delta Air Lines jetliner shortly after takeoff Friday from New York, and pilots who felt a vibration in the plane circled back to land safely at JFK Airport.
Sophie Gregoire Trudeau on navigating post-political life, co-parenting and freedom
Sophie Gregoire Trudeau says there is 'still so much love' between her and Prime Minister Justin Trudeau, as they navigate their post-separation relationship co-parenting their three children.
Last letters of pioneering climber who died on Everest reveal dark side of mountaineering
George Mallory is renowned for being one of the first British mountaineers to attempt to scale the dizzying heights of Mount Everest during the 1920s. Nearly a century later, newly digitized letters shed light on Mallory’s hopes and fears about ascending Everest.
Loud boom in Hamilton caused by propane tank, police say
A loud explosion was heard across Hamilton on Friday after a propane tank was accidentally destroyed and detonated at a local scrap metal yard, police say.