Complex sentence: In 1991 Russell G. Foster and colleagues including Ignacio Provencio discovered a non-rod, non-cone photoreceptor in the eyes of mice where it was shown to mediate circadian rhythms, i.e. the body's 24-hour biological clock.
Split into simpler sentences: In 1991 Russell G. Foster and colleagues, including Ignacio Provencio, discovered a non-rod, non-cone photoreceptor in the eyes of mice. It was shown to mediate circadian rhythms, i.e. the body's 24-hour biological clock.