A population may get deviation from Hardy- Weinberg equilibrium. if it:

Options

A. (I) Shows random mating
B. (2) Doesn’t show gene migration
C. (3) Shows natural selection
D. (4) Doesn’t show gene recombination

Answer

To determine when a population may deviate from Hardy-Weinberg equilibrium, we need to analyze the conditions that must be met for this equilibrium to hold true.

### Step-by-Step Solution:

1. **Understand Hardy-Weinberg Equilibrium**:
The Hardy-Weinberg principle states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of evolutionary influences.

2. **Identify the Assumptions of Hardy-Weinberg Equilibrium**:
For a population to be in Hardy-Weinberg equilibrium, the following assumptions must be met:
- **Random Mating**: Individuals must pair by chance, not according to their genotypes or phenotypes.
- **No Mutations**: There should be no new alleles introduced into the gene pool.
- **No Gene Migration**: There should be no movement of individuals into or out of the population.
- **No Natural Selection**: All individuals must have equal chances of survival and reproduction.
- **Large Population Size**: The population must be sufficiently large to prevent genetic drift.

3. **Analyze the Options Given**:
- **Random Mating**: If random mating occurs, there is no deviation from Hardy-Weinberg equilibrium.
- **Doesn't Show Gene Migration**: If there is no gene migration, the population can still maintain Hardy-Weinberg equilibrium.
- **Show Natural Selection**: If natural selection is present, this leads to differential survival and reproduction, causing a deviation from Hardy-Weinberg equilibrium.
- **Doesn't Show Gene Recombination**: If there is no gene recombination, it does not necessarily lead to a deviation from Hardy-Weinberg equilibrium.

4. **Conclusion**:
The correct answer is that a population may deviate from Hardy-Weinberg equilibrium if it **shows natural selection**. This is because natural selection disrupts the equal chances of survival and reproduction that are necessary for the equilibrium to hold.

### Final Answer:
A population may get deviation from Hardy-Weinberg equilibrium if it **shows natural selection**.