Why is the use of a molecular clock controversial?Multiple choice question.It is only useful in some species.It assumes that rates of evolution are different for different genes.It assumes that DNA divergence rates are constant over time.It does not incorporate information from the fossil record about the timing of evolutionary events.
Question
Why is the use of a molecular clock controversial?Multiple choice question.It is only useful in some species.It assumes that rates of evolution are different for different genes.It assumes that DNA divergence rates are constant over time.It does not incorporate information from the fossil record about the timing of evolutionary events.
Solution
The use of a molecular clock is controversial for several reasons:
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It assumes that DNA divergence rates are constant over time: This is a major point of contention because it's known that mutation rates can vary greatly among different species and even among different genes within the same species. This assumption can lead to inaccurate estimations of divergence times.
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It does not incorporate information from the fossil record about the timing of evolutionary events: The molecular clock method relies solely on genetic data and does not take into account fossil evidence. This can be problematic because the fossil record can provide important context and validation for estimated divergence times.
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It assumes that rates of evolution are different for different genes: This is another assumption that can lead to inaccuracies. While it's true that some genes evolve at different rates than others, this is not always the case. This assumption can lead to over or underestimations of divergence times.
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It is only useful in some species: While the molecular clock method can be useful in some cases, it's not universally applicable. Some species may not have enough genetic variation to make accurate estimations, and in others, the rate of mutation may be too high to make meaningful comparisons.
So, all the options are correct.
Similar Questions
What is the main assumption behind the idea of a molecular clock?Multiple choice question.A constant rate of evolution of a moleculeA constant radioactivity rate in fossilsThe presence of a stable molecule that does not change over timeA constant rate of breakdown of an unstable molecule over time
Select all that applySelect all of the following that are true about molecular clocks.Multiple select question.They use the mutation rate of genes to determine the time of divergence from a common ancestor.They can be used to predict when new species are going to form in the future.They can be used to estimate when humans and chimps diverged from a common ancestor.They can be used in absolute dating of fossils.
Why is mtDNA referred to as a molecular clock?2018 Atomi QuestionA(Choice A)It replicates in synchrony with the cell cycleB(Choice B)We use it to estimate the age of individualsC(Choice C)Alterations in mtDNA occur irregularlyD(Choice D)We use it to estimate the date that different species diverged
A(n) clock uses differences in DNA to determine when organisms diverged from a common ancestor.
The Molecular Clock through evolution is determined by the rate of mutation and the degree of purifying selection. The Clock runs slower in what parts of the genome? Exons Polyadenylation sequences Introns 5' untranslated regions Long-repetitive sequences
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