CLOCK and cancer: Naturally occurring ratiometric responses have been observed in ATP/ADP management (Atkinson, 1968), X versus autosomal chromosome levels (Madl & Herman, 1979), circadian clock determination (Li et al, 2016), cancer cell clinical resistance (Raisova et al, 2001), and sugar source utilization in yeast (Escalante‐Chong et al, 2015).