Vagaries of the molecular clock

Vagaries of the molecular clock.

The hypothesis of the molecular evolutionary clock asserts that informational macromolecules (i.e., proteins and nucleic acids) evolve at rates that are constant through time and for different lineages. The clock hypothesis has been extremely powerful for determining evolutionary events of the remote past for which the fossil and other evidence is lacking or insufficient. I review the evolution...

The vagaries of informed consent.

The Vagaries of Adipose Tissue Innervation

Adipose tissue does not seem to be innervated in any significant manner by the vagus nerve after all. As reported by Giordano et al. in this issue, retrograde tracing with pseudorabies virus from at least one fat pad in the Syrian hamster reveals only the occasional neuron in the vagal motor nucleus and nerve fibers in adipose tissue of mouse, rat, and hamster do not exhibit any of the markers ...

Vagaries of adipose tissue innervation.

ADIPOSE TISSUE DOES NOT SEEM to be innervated in any significant manner by the vagus nerve after all. As reported by Giordano et al. (9) in this issue, retrograde tracing with pseudorabies virus from at least one fat pad in the Siberian hamster reveals only the occasional neuron in the vagal motor nucleus and nerve fibers in adipose tissue of mouse, rat, and hamster do not exhibit any of the ma...

On the overdispersed molecular clock.

Rates of molecular evolution at some loci are more irregular than described by simple Poisson processes. Three situations under which molecular evolution would not follow simple Poisson processes are reevaluated from the viewpoint of the neutrality hypothesis: concomitant or multiple substitutions in a gene, fluctuating substitution rates in time caused by coupled effects of deleterious mutatio...