Temporal Niche choice

The majority of animals restrict their behavioural activity to defined times during the 24-hr day. This temporal niche is specified by an intricate interplay between the animal’s circadian clock and external factors like preferred temperature, light intensity, predators and food availability. Being active at the ‘wrong time’ can have severe impact on an organism’s fitness. But can animals actively choose their preferred temporal niche, and do individuals of the same species and population differ in their choice?

How does light synchronise the molecular clock works?

Most clock genes are expressed in a rhythmic fashion, meaning that like the biological processes they control, their expression reaches peak and trough values once during a 24-hr day (Stanewsky et al., 2003). In order to adjust these molecular oscillations to changing environmental conditions (for example the seasonal changes of day length), clock gene expression must somehow respond to changes in illumination.