How we come to acquire our sense of humor, however, has not been studied in depth, and infant-development researchers are only now beginning to shed light on how our funny bones come into being.
One thing's for certain: Our capacity for humor develops early.
And in a 2001 study, 87 percent of parents of 8-month-old infants said that their babies intentionally tried to make them laugh, such as by increasing the frequency of an action after noticing that it elicited laughter.
Want to see whether your own baby has developed a sense of humor?
Below, I've adapted a 2012 study from the journal Infant and Child Development so that you can perform the experiment on your own baby. It deals with when and how babies recognize certain things as humorous, and how parents can help their children learn what's funny.
Age range: 3 to 6 months
Research areas: Cognitive, behavioral, social, and emotional development
Engage in a 10-minute unstructured play session with your baby, during which you should do whatever you normally do to make your baby laugh or smile.
Speaking in "motherese," or smiling or laughing yourself, may elicit laughter from younger infants, around 3 to 4 months old, but is less likely to get a giggle out of older infants, around 5 to 6 months old.
On the other hand, clowning – defined as absurd nonverbal behavior, such as making odd facial expressions or sounds, or performing strange or absurd actions – will not only be more effective at making your baby laugh than any other strategy, but also, it will grow more effective the older your baby gets.
In a 2012 study of babies between 3 and 6 months old, parents were videotaped in their homes as they attempted to make their babies laugh.
The researchers found that motherese elicited laughter or smiles in 17 percent of 3-month-olds, but that declined over time to only 10 percent of 6-month-olds. A parent's smile or laughter was infectious in 22 percent of 3-month-olds, but it also declined to only 6 percent of 6-month-olds.
Clowning, on the other hand, got laughs or smiles out of 41 percent of 3-month-olds, and that percentage grew over time to 63 percent of 6-month-olds.
The researchers noted that with age, the babies exhibited more clowning behaviors themselves, and parents' amused reactions to those behaviors appear to reinforce them.
Why, though, do parents so frequently use clowning in an attempt to make young infants laugh? After all, at least initially, infants don't know what to make of this behavior.
The researchers in the 2012 study suggest an answer. At the very least, clowning behavior is distinctly different than normal caregiving behavior, and so it is more likely to capture an infant's attention. If infants then notice that such behaviors are frequently paired with smiles and laughter, they are likely to eventually pick up on the humorous nature of the actions.
In just the span of a few months, your baby is likely to develop marked sophistication in her sense of humor. It'll be a few years before she hits the standup circuit, but she's certainly starting to identify what things are funny, and she's testing them out on her favorite audience – you.
You can help her further develop her sense of humor by regularly spending time clowning around with her. Here are a few goofy activities mentioned in the study that are likely to get a chuckle out of her:
For more experiments like this one, as well as the latest news about infant research and other resources for new parents, visit ExperimentingWithBabies.com.
Freud, Sigmund. Jokes and Their Relation to the Unconscious. London: Penguin Books, 1916, 1991.
Mireault, Gina; Poutre, Merlin; Sargent-Hier, Mallory; Dias, Caitlyn; Perdue, Brittany; and Myrick, Allison. "Humour Perception and Creation Between Parents and 3- to 6-month-old Infants," Infant and Child Development, 21:4(338-347), July/August 2012.
Reddy, Vasudevi. "Infant clowns: The interpersonal creation of humor in infancy, Enfance, 53:3(247-256), 2001.