Today’s Solutions: February 01, 2026

A curious research team from MIT recently dived into this intriguing question. If you think about it, we only share saliva with our nearest and dearest. From kissing, to sharing forks, or eating the same ice cream cones, it signifies a close bond. This could be between parents, siblings, extended family, or friends.

The study suggests as small children are always watching and absorbing, they manage to figure out social dynamics through observing this phenomenon. The way in which the team came to this conclusion was by using puppets.

In the experiment, the babies were shown a display of puppets and adults sharing saliva, followed by a video of a puppet ‘crying’. Starting at an age of eight months old, the subjects were more likely to look at an adult that had swapped saliva with this puppet than one who hadn’t.

The result, published in Science, describes how the team used other experiments similar to these. Displaying saliva sharing through orange slices and utensils, the results came to the same conclusion. Of course, scientists can’t know exactly what is going through the babies’ brains. Although, tracking their eye line is a great clue.

The study only focussed on children in the United States. Therefore, across different cultures, where different hygiene and eating practices are carried out, this cue may not be there. Although, it is still an interesting experiment to show how small children can pick up on social interactions. Other behaviors, such as hugging, are likely to also play a role in perceived intimacy, an exciting future avenue for research to go down.

Understanding how the human mind is evolutionarily programmed is a puzzle that scientists have been tackling for centuries. From the psychology of consumerist behaviors used in marketing strategies, to understanding our addictive tendencies to treat diseases such as alcoholism, we are very complex beings psychologically.

Source study: ScienceKids attend to saliva sharing to infer social relationships

Solutions News Source Print this article
More of Today's Solutions

Spray-on powder developed in South Korea stops severe bleeding in just one se...

BY THE OPTIMIST DAILY EDITORIAL TEAM Stopping life-threatening bleeding often comes down to a matter of seconds. Now, scientists in South Korea may have ...

Read More

Only have 10 minutes? This quick burst of exercise may cut your cancer risk

BY THE OPTIMIST DAILY EDITORIAL TEAM We already know working out is good for your heart, your waistline, and your mental state. But it ...

Read More

Study confirms you slow degenerative aging by picking up the pace

It’s no surprise that maintaining an active lifestyle is linked to staving off age-related diseases such as heart damage, memory loss, and cognitive decline. ...

Read More

Inclusive learning through play: Lego introduces braille bricks for vision-im...

Here at The Optimist Daily, we often tout the many wonderful initiatives spearheaded by well-known Danish toymaker Lego. From its commitment to sustainable practices, its ...

Read More