In 1983, social scientist David Chambers published a landmark study on children’s drawings. During the late 1960s and the 1970s, teachers asked nearly 5,000 children to draw a scientist. A singular theme emerged: The scientists were men. Only 28 students drew female scientists.

In the past five years, David Miller and his Northwestern colleagues reviewed 78 such studies completed after Chamber’s report. After 1980, 3 in 10 students drew women as scientists. Younger children, young girls in particular, were the most likely to sketch female scientists, the report said. Pooling pictures by nearly 21,000 students, from kindergarten to grade 12, the authors also found a change in perception around age 8. Before middle school, most girls drew female scientists and most boys drew male scientists. But as students grew older, the proportion of male scientists in their drawings increased.

 

Alligator, crocodile have different bones

How do you tell an alligator from a crocodile? The most obvious way to discern the two reptiles is to stare down their sinister snouts. Alligators have U-shaped faces that are wide and short, while crocodiles have slender, almost V-shaped muzzles. When an alligator closes its mouth, you tend to see only its upper teeth. Crocodiles on the other hand flash a toothy grin with their top and bottom teeth interlacing.

Now, researchers from Japan have identified what they believe to be another feature that sets the reptiles apart: Alligators tend to have shorter humerus bones in their forelimbs and shorter femurs in their hind limbs than crocodiles, the team reported. “This information could help explain differences in their ecology and locomotion, including the strange fact that, while small crocodiles have been observed to bound and gallop, alligators have not,” said Julia Molnar an evolutionary biologist.

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