Babies are individuals: Don’t fret the milestones

Nice post on Slate about how developmental milestones can be meaningless and create needless worry.

A little less than a century ago, Arnold Gesell, a developmental scientist at Yale, proposed that motor skills were related to the maturing of the brain. This led to the pronouncement that all infants would pass through the same steps of development – sitting, walking, talking – in the same order and at the same time.

Babies are remarkably adaptable

It turns out that the theory was just plain wrong. Not only were the developmental milestones inaccurate, but so was the fundamental assumption that muscular activity is strictly a function of how the brain matures.

Human beings have a remarkable ability to adapt to their environment. That’s what has allowed humans to thrive in climates from the tropics to the Arctic. Babies develop in response to the culture and environment in which they’re raised.

One study found that mothers of different cultural backgrounds, living in the same city at the same time, could accurately predict the development of motor skills in their infants, even though the milestones for each group differed by several months.

A total of 124 mothers from three cultural groups living in the same British city were asked to give the ages at which they expected their one-month-old infants to achieve three motor milestones. Jamaican mothers expected their infants to sit and walk much earlier than their English and Indian counterparts. The Indian mothers gave later estimates for crawling than those of the other two groups. The actual ages at which the abilities were attained closely reflected the cultural differences in expectations between the Jamaican and English mothers. Jamaican mothers were particularly accurate in predicting sitting age.

Here’s a trailer from the movie Babies, which follows four babies from four different cultures from birth to their first steps.

The young Einstein

Parents sometimes take heart from stories of the young Albert Einstein, who reputedly didn’t talk until he was four. Although Einstein’s developmental history may have been unusual, claims of his learning disabilities – not reading until he was nine, failing his college entrance exam, losing three teaching positions in two years – are exaggerated. The record is set straight in this discussion of the book Subtle is the Lord: The Science and the Life of Albert Einstein

Update:
Review of the documentary Babies in The Washington Post.

Sources:

Nicholas Day, Can Your Baby Wield a Machete? The developmental milestones parents obsess over are meaningless, Slate, May 3, 2010

Brian Hopkins, Tamme Westra, Maternal Expectations of Their Infants’ Development: Some Cultural Differences, Developmental Medicine & Child Neurology, Vol. 31 Issue 3, pp 384-390, November 12, 2008

Babies, website for the movie

Einstein’s Biographers Disprove Claim that He was Dyslexic, Audiblox

Abraham Pais, Subtle is the Lord: The Science and the Life of Albert Einstein