Which of the following statements about the use of molecular clocks in phylogenetic analyses is true?
A) A given gene usually evolves at the same rate in two different species regardless of differences in generation time of the species.
B) Because changes in DNA sequences occur very slowly, molecular clocks can be used only to date evolutionary divergences that occurred millions of years ago.
C) Molecular clocks must be calibrated with independent data, such as the fossil record.
D) Even in a group of closely related species, different genes have been found to evolve at different rates.
E) Both c and d

Question

Quizplus · Accepted Answer

Molecular clocks must be calibrated with independent data, such as the fossil record (choice C), but different genes have been found to evolve at different rates even in a group of closely related species (choice D). This means that different genes may be useful for dating divergences that occurred at different times. Additionally, while changes in DNA sequences do occur slowly, molecular clocks can still be used to date relatively recent evolutionary divergences, as long as the appropriate genes are used and a reliable calibration point is available.

Which of the Following Statements About the Use of Molecular