Which statement best contrasts microevolution and macroevolution?

Which statement best contrasts microevolution and macroevolution?

• A. Microevolution involves changes in allele frequencies within populations over generations.
• B. Microevolution refers to changes in allele frequencies within populations over generations; macroevolution refers to large-scale patterns above species level, such as speciation.
• C. Macroevolution is simply slower microevolution.
• D. Macroevolution only occurs in plants.

Answer: (B)

The main idea here is the difference in scope between microevolution and macroevolution. Microevolution describes changes in allele frequencies within a population over generations—the small-scale genetic shifts you can observe within a species. Macroevolution, on the other hand, looks at large-scale patterns that occur above the species level over longer timescales, such as the origin of new species (speciation), major morphological changes, and broad evolutionary trends across groups of organisms. That’s why the statement that microevolution involves allele-frequency changes within populations over generations while macroevolution refers to large-scale patterns above the species level, such as speciation, best captures the contrast. It emphasizes the different levels of biological organization and timescales. Other options aren’t as accurate for this contrast: one just repeats microevolution without addressing macroevolution, another incorrectly limits macroevolution to plants, and the idea that macroevolution is simply slower microevolution misstates the relationship by implying the same process operates at different speeds rather than different scales and patterns.

The main idea here is the difference in scope between microevolution and macroevolution. Microevolution describes changes in allele frequencies within a population over generations—the small-scale genetic shifts you can observe within a species. Macroevolution, on the other hand, looks at large-scale patterns that occur above the species level over longer timescales, such as the origin of new species (speciation), major morphological changes, and broad evolutionary trends across groups of organisms.

That’s why the statement that microevolution involves allele-frequency changes within populations over generations while macroevolution refers to large-scale patterns above the species level, such as speciation, best captures the contrast. It emphasizes the different levels of biological organization and timescales.

Other options aren’t as accurate for this contrast: one just repeats microevolution without addressing macroevolution, another incorrectly limits macroevolution to plants, and the idea that macroevolution is simply slower microevolution misstates the relationship by implying the same process operates at different speeds rather than different scales and patterns.