Are babies born with an innate sense of fairness?

It's amazing how something as fun as playing with puppets can add to science.

In a new study of 19- and 21-month old children, researchers using two giraffe puppets have found that the little ones had "a general expectation of fairness," and could apply it properly to various scenarios, according to Stephanie Sloane, a graduate student at the University of Illinois.

In one of two experiments, children sitting on their moms' laps, watched two giraffes dancing next to each other on a stage, reports Time. A person appears through a window and says "I have toys!" Both giraffes exclaim "Yay, yay!"

Then, in some versions, the person gives one toy to each giraffe. In others, one giraffe gets both toys. And the two giraffes take a moment to look at their loot.

"Prior studies have shown that babies reliably pay attention longer to things that surprise them or violate their expectations," reports Time. "In the giraffe experiment, toddlers stared at the scene much longer after the pause when the second giraffe didn't get a share of the goodies."

Ms. Sloane describes the reaction as being due to a "skeleton of general expectations about fairness."

A second experiment featured adults who are told to put away the toys in exchange for stickers. Toddlers were surprised to see a slacker adult who did not put any toys away get rewarded.

Another recent study suggests that not only do kids develop a sense of fairness early, they'll support the punishment of those who don't respect it.

Again, this study used hand puppets to stage bad behaviour, then researchers asked babies as young as eight months to pick their favourite puppets or reward them; they routinely picked the puppets who were nice or who were vindictive toward the bad character.

"These findings suggest that, from as early as eight months, we are watching for people who might put us in danger and prefer to see antisocial behaviour regulated," said lead author and University of British Columbia psychologist Kiley Hamlin.

Would knowing just how young children are when they pick up on notions like fairness inspire you to be a little more, well, inspiring on that front?