This article has been revised to reflect the following corrections and clarification:

CORRECTION: April 24, 2010

An earlier version of the Apr. 23 news article "A Ticking Biological Clock" stated that Shawn Low '11 created a model of the biological clock. In fact, he did not create a model of the biological clock, but used existing mathematical models of the clock developed by others to predict the effects of temperature changes on the in vitro clock.

The article also stated that the temperature compensation of period length results from a process of entrainment. In fact, Low proposed that the small number of temperature-sensitive rate constants may play an integral role in entraining the clock to diurnal temperature cycles in the environment.

CLARIFICATION: April 26, 2010

The article also stated that Low's research focuses on three proteins that comprise the biological clock. To clarify, he focuses on temperature compensation of the three-protein post-translational oscillator in the cyanobacterial biological clock.