Development of colony phenotype in social insects controlled by frequency-dependent thresholds among workers

The frequency of workers adopting different behaviours often depends on thresholds. If too few workers are foraging, for example, then those workers with relatively low foraging thresholds begin to collect food. The regulation of colony phenotype is controlled by frequency-dependent feedback among worker threshold values. I show that, for a given average threshold value among workers, variability in thresholds influences the frequency of workers that adopt a particular behaviour. This conclusion applies whenever the tendency of a developmental unit to adopt a particular phenotype depends on the frequency of other units with that phenotype. Social insects are unusual, however, because the distribution of thresholds among developmental units (workers) depends on the number of times the queen has mated.