However other researchers have theorized that they may also do this for a source of pleasure.

Some researchers theorize that this is in part due to physiological differences between men and women.

Researchers now theorize that this something is a protein in muscle fiber.

Researchers had long theorized as much but until now had only indirect evidence.

Perhaps because of this disturbance, researchers theorize, many of the children do not begin to walk and talk when they should.

A smaller amount of the alcohol they drink would be diluted by the body's water, the researchers theorized.

But some researchers had theorized that the lights might cause nearsightedness in infants.

Some researchers have theorized that shoplifting is an unconscious attempt to make up for a past loss.

The researchers theorized that this was because of the special way in which the blind conceptualize their external environment.

Researchers theorized about the values shared by school officials, students and parents - but their explanations remained speculative.