The differential distribution of wing length in Drosophila , with larger wings in northern areas and smaller wings in southern climates, provides evidence that:
A) wing length is not a heritable trait.
B) the fossil record is usually inaccurate.
C) the molecular clock cannot be applied to fruit fly traits.
D) chance is the most important agent in evolutionary change.
E) natural selection is the most important agent in evolutionary change.

Question

Quizplus · Accepted Answer

The variation in wing length among Drosophila populations in different climates suggests adaptation to environmental conditions, which is a result of natural selection. Larger wings in colder climates may help with heat retention or more efficient flight in less dense air, while smaller wings in warmer climates could reduce overheating or require less energy to maintain. This is evidence that natural selection, rather than chance or non-heritable factors, plays a key role in evolutionary changes.

The Differential Distribution of Wing Length in Drosophila , with Larger