You wouldn't expect babies to know much about food. After all, they tend to put almost everything in their mouths. Yet it turns out that infants as young as six months old have more knowledge about what's safe to eat than you might expect. Scientists have discovered that they tend to expect that plants are food sources, but only after an adult shows them that the food is safe to eat.
"Plants are often peripheral to modern life, but they were central to fundamental problems of determining what is food and what is fatal across evolutionary time," said Annie Wertz, one of the researchers, in a news release. "Humans relied on gathered plant resources for food, but many plants are toxic and potentially deadly."
In fact, children actually identified plants as being edible over human-made objects. After witnessing an adult put part of a plant and part of a human-made object in her mouth, infants at 6- and 18-months of age preferentially identified the plants as the food source.
"Young children's decisions about what to eat are, famously, not determined by simply copying adult behavior," said Wertz and Karen Wynn, one of the researchers, in a news release.
What's interesting is that children can determine that one "food" choice is preferable over another-despite an adult treating both in the same manner. Instead of imitating an adult's behavior outright, children instead tend to go for specific entities; in this case, they choose plants.
"Together, these experiments show that infants use social information from adults to rapidly and selectively identify plants as food sources," said Wertz in a news release. "More broadly, this suggests that humans, unlike some other non-human primates, don't simply consider anything that goes into the mouth to be food. Instead, they also take the type of object into consideration."
The findings are published in the journal Psychological Science.
