22) Chambers, M.L., Hewitt, J.K., Schmitz, S., Corley, R.P., & Fulker, D.W. (2001). Height, Weight, and Body Mass Index. In R. Emde & J. Hewitt (Eds.), Infancy to Early Childhood: Genetic and Environmental Influences on Developmental Change (pp 292-306). Oxford University Press: New York, New York.

This study explored the contribution of genetic and environmental influences to height and weight. Twin pairs were measured and weighed at ages 14,20,24 and 36 months. Researchers found that genetic influence accounted for between 61% and 82% of variation in height, and between 78% and 87% of variation in weight. At certain age points environmental factors were more influential than at others. Researchers also looked at the results of other measures including those that assessed intelligence, shyness, mood and sociability to determine if there were any correlations between body type and other psychosocial variables. They found little to no evidence of correlations between body type and early childhood temperament, psychosocial, or cognitive development.