The Molecular Clock Has Limited Usefulness for Estimating Divergence Times

question 41

Multiple Choice

The molecular clock has limited usefulness for estimating divergence times among species in part due to the saturation of DNA sequences. This occurs because

• A) DNA sequences are unable to revert back to previous allelic states.
• B) the variation in the substitution rate between closely related lineages prevents accurate estimation of divergence time.
• C) variation in population sizes among lineages changes the effect of genetic drift.
• D) in highly diverged lineages, substitutions will occur at sites that have been substituted previously.

---

Definitions:

Extrapyramidal Effects

Side effects caused by certain medications, affecting movement control, such as tremors or stiffness, not involving the pyramidal tracts.

Antipsychotic Medication

Drugs used to treat psychiatric conditions, primarily to manage psychosis, including schizophrenia and bipolar disorder.

Bradycardia

A condition characterized by a slower than normal heart rate, often leading to insufficient blood flow to the body's organs and tissues.

Advanced Directive

A legal document in which individuals specify what actions should be taken for their health if they are no longer able to make decisions due to illness or incapacity.