Watching a toddler take his first steps, it's obvious he's learned through observation and encouragement. But are our brains specially wired to learn this important behavior so early on?
Scientists are beginning to think so, according to one article published in the journal Science.
By looking at the body's neural circuitry in rats, humans and other animals, researchers pieced together that the process of learning to move around looks similar across species, despite most mammals moving on four legs and Homo sapiens stepping with two. The finding indicates that humans' innate ability to walk has a lengthy evolutionary history.
Previously, neuroscience experts thought pathways in the nervous system changed dramatically during human development, allowing new pathways to replace the deeply -rooted connections shared with other mammals. Not so, says lead researcher Francesco Lacquaniti, according to one article in The Atlantic. He provided an analogy comparing learning to walk with learning to drive a stick shift car. New drivers first learn the basic gears, but then add more with time. Yet even the most advanced drivers still need the first gear to drive. The same principle applies to learning to walk, with humans and animals sharing a common circuitry and gradually building on it in different ways.
Instead, toddlers continue to use these primitive connections in muscles, adding to them as they become more skilled at walking. In the study, Lacquaniti and colleagues looked at the electrical activity in muscles in newborns, toddlers, preschoolers and adults. They found the same connections were at play among cats, guineafowl, non-human primates and rats as well.
Scientists estimate that this circuitry became more diversified in animals at least 100 million years ago, say the article's authors.
English, Marianne. 2011. "We Are Hardwired to Walk". Discovery News. Posted: November 18, 2011. Available online: http://news.discovery.com/human/humans-walking-evolution-111121.html