Colin Stephenson Pittendrigh (October 13, 1918 – March 19, 1996)[1] was a British-born biologist who spent most of his adult life in the United States.
Pittendrigh is regarded as the "father of the biological clock," and founded the modern field of chronobiology alongside Jürgen Aschoff and Erwin Bünning.
He studied the epidemiology of malaria transmitted by mosquitoes breeding in epiphytic bromeliad ("tanks" formed by overlapping leaves) in the forest canopy.
Soon after, they moved to Trinidad and lived in the rain forest, where Pittendrigh worked on malaria control as part of the war effort.
[1] Pittendrigh was an avid fly fisherman and outdoorsman, and he and his wife retired to Bozeman, Montana because of their love of the Rocky Mountains.
[5] When he finished at Columbia in 1947, he joined the faculty at Princeton,[1] as an assistant professor of biology where he began his work concerning circadian rhythms.
[6] In 1969 Pittendrigh left Princeton to join the faculty of Stanford where he helped found the program in Human Biology and later became the director of the Hopkins Marine Station.
Despite opposing views, Aschoff and Pittendrigh remained close friends, and they had a lifelong intense exchange of notes and ideas.Their research was described by Serge Daan as "always in harmony, never in synchrony.
Spraying a copper sulfate (CuSO4) solution (non-toxic to humans) on the bromeliads killed them and destroyed the mosquitoes' breeding environment.
In addition to his malaria research, Pittendrigh's studies of the daily activity rhythms of mosquitoes sparked his interest in biological clocks, a subject which he came to wholly pursue later at Princeton.
This is reflected through the expression: Δφ(φ)= τ - T.[8] While the PRC has been invaluable towards understanding entrainment, there are several notable problems with the model.
[13] Pittendrigh and Daan published a set of five papers reporting their findings on the properties of nocturnal rodents' circadian pacemakers.
Its implication on real life is that most diurnal organisms, including humans, have periods longer than 24 hours; they therefore tend to have a larger advance zone in their PRC.
The model quantitatively accommodates τ and α summarized in Aschoff's rule, and Aftereffects on free-running period are predicted from prior light-dark history.
[19] This work was crucial in developing the Photo-Periodic Response Curve (PPRC), a phase-response-curve that factors in seasonal daylength changes when describing entrainment.
Pittendrigh also collaborated with Knopka on the study of drosophila per mutants (which genetically have longer or shorter intrinsic periods due to mutation in the per gene) and their different entrainment responses to temperature and light stimuli.