molecular clock

More likely, the assumptions behind molecular clocks do not hold exactly.

Molecular clock evidence suggests an earlier date for their origin.

The critics also began wondering just how reliable the molecular clock was.

Researchers often estimate the ages of groups using what are called molecular clocks, as was done in the new study.

Plants keep track of the time of the day with a molecular clock.

These dates were all calculated using a molecular clock.

Application of molecular clock allowed to estimate divergence times for these groups.

Finally, we applied these different estimators to five published data sets from a molecular clock study.

Branch lengths can be calculated with and without the molecular clock hypothesis.

A region which mutates at predictable rate is a candidate for use as a molecular clock.

However, hominins discovered more recently are somewhat older than the molecular clock would suggest.

The wide range of dates is due to the different records used to calibrate the molecular clock.

In particular, scientists who rely mainly on fossil studies question the reliability of such molecular clocks.

By knowing how many differences accumulate, for example, every million years, researchers have calibrated their molecular clock.

The "molecular clock hypothesis" seems to fit these facts.

Without any type of feedback repression, the molecular clock would have a period of just a few hours.

During the succeeding years, Zuckerkandl worked to refine the molecular clock.

Such mutations occur at a steady rate, forming the basis for the molecular clock.

Researchers such as Ayala have more fundamentally challenged the molecular clock hypothesis.

This molecular clock is based on the rate of changes in proteins shared by different groups of organisms.

The molecular clock runs into particular challenges at very short and very long timescales.

But researchers are still arguing over whether molecular clocks tick regularly enough to provide accurate ages.

It must be remarked that Ericson et al.'s study used an entirely unreliable molecular clock.

Thus the neutral theory of evolution provides a molecular clock, given that the assumptions are fulfilled which may not be the case in reality.

To achieve this, the molecular clock must first be calibrated against independent evidence about dates, such as the fossil record.