About the question:
I failed to find the complete question. However, I will explain why this population is considered to be in Hardy-Weinberg equilibrium, and what the destiny of the alleles is.
Answer:
This population is in equilibrium because it accomplishes all the H-W assumptions for a population in equilibrium. Genetic nor allelic frequencies will change generation after generation. Alleles will remain equal.
Step-by-step explanation:
Available data:
- A single gene controls wing color
- Half of the moths have white-spotted wings
- half of the moths have plain brown wings
- W allele is dominant and expresses white wings
- w allele is recessive and expresses brown wings
- Individuals mate randomly
- No natural selection
We will know by theory if this population is or is not in equilibrium Hardy-Weinberg if the population is in concordance with the assumptions of the theory. So let us first analyze the Hardy-Weinberg assumptions for a population in equilibrium:
• Random matings: Any individual get crossed with any other individual
• No superposed generations: each individual can leave their gametes in the pool only once.
• No mutations: No mutations originate any new gametes.
• No migration: No incorporation of gametes from other populations.
• Infinite population size: the probabilities of randomly taking an A gamete from the pool are p, and the probability of taking a B gamete is q.
• No natural selection: Each individual has equal surviving and reproducing probabilities as any other, contributing proportionally to the gamete pool.
So, the exposed population
- is isolated, meaning that there is no gene flow from other populations. No new genes will be introduced.
- has no mutations, so no allele will change to express a new form
- individuals mate randomly
- there is no natural selection acting on this group as an evolutive force that might alter the equilibrium.
Genetic nor allelic frequencies will change generation after generation.
In a Hardy-Weinberg population, where allelic frequencies are p and q (assuming a diallelic gene), genotypic frequencies after one generation of random matings are p², 2pq and q². The allelic frequencies, as well as the genotypic frequencies, remain equal after successive generations. Alleles will remain in the population from many generations.