Probing question: What is a molecular clock?

It doesn't tick, it doesn't have hands, and it doesn't tell you what time of day it is. But a molecular clock does tell time -- on an epoch scale. The molecular clock, explained S. Blair Hedges, is a tool used to calculate the timing of evolutionary events.

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<p><a href="http://www.physorg.com/news146418967.html">Probing question: What is a molecular clock?</a></p> <p>It doesn't tick, it doesn't have hands, and it doesn't tell you what time of day it is. But a molecular clock does tell time -- on an epoch scale. The molecular clock, explained S. Blair Hedges, is a tool used to calculate the timing of evolutionary events.</p>