Darwin knew that nature had to produce variations before natural selection could act.

Even a slight change at the beginning of the Game produced drastic variation in the results.

Starting in the mid-1980s, many other companies produced their own dialects or variations on the product and language.

Several radio stations have produced provincial variations on the theme.

This method produced variations on a theme and were moderately successful.

It is possible to combine grinds or produce other variations.

They are able to produce random variations, which are new.

Skill using the wrist could produce slight variations of the wave.

Varying the tension of the tape produces variations in tones.

Because the new tools reduce the time and cost of designing products, some companies find they can afford to produce variations on existing designs.