LONDON, Aug. 19 (Xinhua) -- A four-year-old child's ability to draw could be an indicator of intelligence at age 14, according to a study published on Tuesday in the British journal Psychological Science. The researchers from King's College London (KCL) studied 7,752 pairs of identical and non-identical twins, and found that the link between drawing and later intelligence was influenced by genes. At the age of 4, children were asked by their parents to complete a 'Draw-a-Child' test. Their drawings were rated from 0 to 12, based on the presence and correct number of body-parts, like arms, legs, head, eyes and nose. The children were also given verbal and non-verbal intelligence tests at ages 4 and 14. According to researchers, the test was devised in the 1920's to assess children's intelligence, so it's not surprising that the test correlated with intelligence at age 4.However, they found that higher scores on the test were also moderately associated with higher scores of intelligence at 14. The researchers also measured the heritability of figure drawing. Identical twins share all their genes, whereas non-identical twins only share about 50 percent. Overall, at age 4, drawings from identical twin pairs were more similar to one another than drawings from non-identical twin pairs. Therefore, the researchers concluded that differences in children's drawings have an important genetic link. They also found that drawing at age 4 and intelligence at age 14 had a strong genetic link. "Drawing is an ancient behaviour, dating back beyond 15,000 years ago," Dr. Rosalind Arden, lead author of the paper from KCL, said that: "This capacity to reproduce figures is a uniquely human ability and a sign of cognitive ability, in a similar way to writing, which transformed the human species' ability to store information, and build a civilisation." What do we know about the twins from the passage?
Those who could draw better at 4 tend to be more intelligent at 14. Twins who look similar to each other draw better pictures. They were chosen to take the drawing test by the researchers. They were tested on how smart they were once.