Question

A student claims that dominant tracks are always the most common traits is this true why or why not a no dominant traits only show up if they are inherited how common they are is not influenced by this fee no dominant traits and general tend to be less common in the population and continue to persist only because they are dominant over more common recessive Ellies say yes dominatrates are called dominant because they are the most common D yes Dominic traits become more common over time as they are passed down from generation to generation excessive aliens continue to become less common over time

Answer 1

The student's claim that dominant traits are always the most common traits is not true. Here’s why:

1. Dominance Does Not Equal Commonality: A trait being dominant means that only one copy of the allele is needed for the trait to be expressed, but it does not inherently make that trait common in the population. For example, the allele for free earlobes is dominant, while attached earlobes are recessive. In some populations, attached earlobes (the recessive trait) may be more prevalent despite being recessive.

2. Inheritance Patterns: Dominant traits can be less common if the allele responsible for the trait is rare in the gene pool. Just because a trait is dominant, it doesn’t guarantee that it will be found in the majority of individuals.

3. Frequencies Can Change: Over time, due to selective pressures or changes in the environment, the frequencies of alleles can fluctuate. Dominant traits can become rare, and recessive traits can persist in the population despite their recessive nature, often carried by heterozygous individuals.

4. Misleading Terminology: The term "dominant" is about the expression of the trait (i.e., whether it shows up in the phenotype when present), not about how frequently it occurs in the population.

Therefore, the correct understanding is that being dominant does not guarantee that a trait will be commonly observed in a population. A more scientifically accurate perspective would be to recognize that both dominant and recessive traits can vary in prevalence, depending on various factors including genetics, environment, and population dynamics.