Even though circadian clocks in bacteria, fungi, plants and animals have evolved largely independently and thus are composed of different sets of genes, these clocks show a common structure or underlying principle.
Different sets of experiments were performed.
Several age estimates for the whole U6 mtDNA clade have been calculated with different sets of complete sequences, varying mutation rates and different coalescence-based approaches; including, mean pairwise distances, maximum likelihood, and internally calibrated Bayesian relaxed clock phylogenetics.
Test cricket runs according to a different clock, with a different relation to time and a different set of values.
By contrast, a very different set of proteins forms the circadian timer in the simplest organisms to possess a clock, the cyanobacteria, e.g., S. elongatus.
Further, this study addresses a different set of fundamental biological questions related to the role of unproductive alternative splicing (UAS) in circadian clock regulation for the following reasons.
Despite the potential violation of the molecular clock, divergence of synonymous substitutions was used for dating estimation because it permitted us to use a different set of assumptions (rates of divergence, biogeographic milestones and models of nucleotide substitutions) than two relaxed molecular clock methods: penalized likelihood and Bayesian dating estimation.
