Human babies take a long time to start walking
The onset of walking for human babies is thought to represent a critical milestone in development of the nervous system, when neuronal systems mature enough to coordinate the complex movements of multiple limbs and prevent the animal from falling over.
How long it takes for human babies to start walking is one area that scientists originally thought that humans differ from other mammals.
A human baby only starts to walk on shaky legs around a year after birth, but a foal can get up almost immediately and rodents like mice only require a few hours to start moving around. In a new study published in PNAS, a group from Lund University in Sweden has found why this difference exists – and surprisingly, it’s not because humans are uniquely different.
Most mammals start walking around the same developmental time!
They showed that human babies actually start walking at the same brain developmental stage as most other mammals that walk. If you look at progression of brain development after conception, and not birth, humans start walking at the same relative point in time.
This shows that the neural mechanisms that underlie the ability to walk are very similar across animals and the neural building blocks of human brains come together in a similar manner as even lower mammals that diverged in evolution many millions of years ago.
Analyzing brain development data from other animals allowed them to predict quite accurately when humans would start to walk. Though humans may be different in many ways, motor development of the brain is not one of them.
These findings shed new light on how developmental paths in early life could have been conserved evolutionarily from lower organisms all the way up to humans, and they lead to better understanding of the developmental clock and what events occur at what stage of development, which may have relevance for treating developmental disorders in the future.
“Human babies” Photo by Photostock.
