An alternative, however, is that compound eyes evolved multiple times among the arthropods.

The unit evolved several times until 1921, after which the name was lost during one of many reorganisations.

He believed that the United States government had to evolve several times in order to change.

They have evolved several different times and affect a variety of insects.

Iced Earth's music has evolved and shifted several times during the band's history.

Scales are quite common and have evolved multiple times with varying structure and function.

One question that scientists try to answer through these studies is whether sleep evolved only once or multiple times.

Whether one considers the eye to have evolved once or multiple times depends somewhat on the definition of an eye.

These families are only distantly related, suggesting that this features has evolved several times independently.

Today it is thought that the reduction of the third claw evolved several times independently.