Canaries Genetics: Singing Trait Inheritance

What percentage of the offspring is likely to possess the singing trait when hybrid singing canaries are mated with nonsinging canaries?

1. Approximately 25%

2. Approximately 50%

3. Approximately 75%

4. Approximately 100%

Answer:

When hybrid singing canaries (Ss) are mated with nonsinging canaries (ss), approximately 50% of the offspring are likely to possess the singing trait.

In canaries, the gene for singing (S) is dominant over the gene for nonsinging (s). When hybrid singing canaries (Ss) are mated with nonsinging canaries (ss), the offspring inherit one allele from each parent. Since the singing gene (S) is dominant, individuals with either SS or Ss genotypes will possess the singing trait. Only individuals with the ss genotype will not possess the singing trait. Therefore, approximately 50% of the offspring are expected to inherit the S allele from the hybrid singing canary parent and exhibit the singing trait, while the other 50% will inherit the nonsinging allele from the nonsinging canary parent and lack the singing trait.