molecular clock

American  

noun

1. the changes in the amino acid sequences of proteins that take place during evolution and speciation, and from which the dates of branchings of taxonomic groups can be deduced.

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Example Sentences

Based on genetic data calibrated by fossils, the researchers performed "molecular clock analyses."

From Science Daily • Jan. 23, 2024

Using the estimated mutation rates of the bovine virus and OC43, they created a molecular clock and calculated that the two viruses shared a common ancestor somewhere around 1890.

From Science Magazine • Jan. 11, 2024

The leading theory is that these insects have an internal molecular clock synced to the seasonal flow of fluid, or xylem, that passes through a tree’s roots each spring, which cicadas sip on as food.

From National Geographic • Sep. 5, 2023

Explain how such a molecular clock could be refined to infer time for the evolution of prokaryotes.

From Textbooks • Jun. 9, 2022

That’s because mutations arise at a roughly regular pace, like a molecular clock.

From New York Times • Apr. 8, 2020