Natural selection has the ability to make a population look different when it is coupled with

Options

A. Mutation
B. Migration
C. Reproductive success
D. Genetic equilibrium

Answer

To solve the question regarding what natural selection can couple with to make a population look different, we can analyze each option provided:

### Step-by-Step Solution:

1. **Understand Natural Selection**: Natural selection is a process where organisms better adapted to their environment tend to survive and produce more offspring. This can lead to changes in the traits of a population over time.

2. **Evaluate the Options**:
- **Option 1: Mutation**:
- Mutation refers to a sudden change in the genetic makeup of an organism. While mutations can introduce new traits into a population, they do not necessarily lead to a change in the population's appearance when coupled with natural selection. This is because not all mutations are beneficial or lead to increased survival.
- **Conclusion**: This option is incorrect.

- **Option 2: Migration**:
- Migration is the movement of individuals from one population to another. While migration can introduce new genetic material, it does not inherently lead to a change in the population's appearance when coupled with natural selection. It can maintain or reduce genetic diversity but does not necessarily enhance it.
- **Conclusion**: This option is incorrect.

- **Option 3: Reproductive Success**:
- Reproductive success refers to the ability of an organism to produce offspring that survive to reproductive age. This is a critical factor in natural selection, as those individuals with traits that enhance their survival and reproduction will pass those traits on to the next generation. Thus, when reproductive success is coupled with natural selection, it can lead to significant changes in the population's traits and appearance.
- **Conclusion**: This option is correct.

- **Option 4: Genetic Equilibrium**:
- Genetic equilibrium, or Hardy-Weinberg equilibrium, refers to a state where allele frequencies in a population remain constant from generation to generation. If a population is in genetic equilibrium, it means that there is no evolution occurring, and thus, natural selection cannot act to change the population's appearance.
- **Conclusion**: This option is incorrect.

3. **Final Answer**: The correct answer is **Option 3: Reproductive Success**. This is because reproductive success, when coupled with natural selection, leads to changes in the population's traits and can enhance its overall appearance.