Synchrony, the phenomenon where components of a system experience events in unison, seems to be very common in biological systems. Temporal Clustering or Phase Synchrony, a phenomenon related to synchrony, is where sub-groups (or cohorts) of components synchronize among themselves, but are out of phase with other cohorts.
In bioreactor experiments on yeast metabolic oscillations we discovered a case where a culture of yeast exhibits temporal clustering in which two groups progress through their cell cycles in anti-phase. In these experiments the cell cycle clusters and oscillations in the metabolism are seen to be tightly coupled.
The discovery raises a number of mathematical questions such as: `What accounts for the difference between a system that synchronizes and one that forms clusters?', `What determines the number of clusters that appear?', and `How do individual cells distribute themselves among clusters?'. In this talk we will discuss how questions such as these can be studied mathematically using biologically motivated non-linear models and in many cases answers can be found.
Biologically, the mechanism for the coupling between cell cycle and metabolism is puzzling. We propose a possible mechanism that relies on the fact that in the experiments the bioreactor is operating near carrying capacity.