Natural selection is based on all of the following except
A. Individuals who survive longer tend to have more offspring than those who die young
B. Genetic variation exists within populations
C. Individuals adapt to their environments and, thereby, evolve
D. Populations tend to produce more offspring than the environment can support the best adapted individuals tend to reproduce more
The Correct Answer and Explanation is:
Correct Answer: C. Individuals adapt to their environments and, thereby, evolve
Explanation:
Natural selection, a fundamental mechanism of evolution proposed by Charles Darwin, is based on several core principles:
- Variation: There is genetic variation within populations (Statement B). Different individuals possess different traits, some of which may offer a survival or reproductive advantage in a given environment.
- Overproduction of Offspring: Populations tend to produce more offspring than the environment can support (Part of Statement D). This creates competition for limited resources like food, space, and mates.
- Differential Survival and Reproduction: Individuals who survive longer are more likely to reproduce and pass on their advantageous traits to the next generation (Statement A). Over time, these traits become more common in the population.
- Adaptation Over Generations: While populations evolve over generations due to the accumulation of favorable traits, individuals do not evolve. This is where Statement C is incorrect. Individuals may survive or perish based on their traits, but they cannot adapt in the evolutionary sense during their lifetimes.
Statement C implies that individuals themselves evolve or adapt to environmental challenges, which is a misunderstanding of natural selection. Evolution by natural selection acts on the population level over generations, not on individual organisms. For instance, a polar bear does not develop thicker fur in response to a single cold winter; rather, polar bears with naturally thicker fur survive and reproduce more often, leading to a population with this trait over time.
Therefore, the best answer is C, because it misrepresents the mechanism of evolution by incorrectly attributing adaptive change to individuals rather than populations over time. The rest of the statements accurately reflect the principles of natural selection.