Your dog and your two-year-old nephew seem very similar. They both look up at you with big, sweet eyes or, you know... throw a tantrum in public until you give them a peacekeeping cookie. The comparisons are endless: they have lots of energy, know how to make a mess, like sticking random objects in their mouths, etc. And now, one study tells us what we've always thought to be true. Dogs really are similar to toddlers.
In a January 2017 study, researchers from the University of Arizona studied similarities in cognition between two-year-old humans, dogs, and chimpanzees. The toddlers and dogs responded similarly in many of their verbal and nonverbal assessments, like when researchers hid treats or toys. They also reacted to certain social cues like researchers pointing, whereas the chimpanzees offered no response. Nada. As the study notes, "[dogs] perform more like human infants in cooperative communicative tasks." But if chimps are more closely related to humans, then why are dogs more similar?
While humans and chimps are more similar when it comes to nonsocial, cognitive tasks, toddlers surpass apes with their social cognitive skills and cooperative communication. Somewhere along the line, dogs stepped it up—they share a similar social intelligence to humans (or toddlers, anyway). The study's lead author, Evan MacLean, elaborates to Phys.Org: "One explanation for the similarities between dogs and humans is that the two species may have evolved under similar pressures that favored 'survival of the friendliest,' with benefits and rewards for more cooperative social behavior."
MacLean suggests that studying dogs and domestication could help us learn something about human evolution. These findings might also help researchers better understand certain human disabilities that involve deficits in social skills, such as autism. Dogs are man's best friend, after all—we've been domesticating them for centuries. But all of this is beside the point... puppies and toddlers are the all-time cutest combo.