if a trait A exists in 10% of a population of an asexually reproducing species; and a trait B exists in 60% of the same community, which trait is likely to have arisen earlier?
Answer:
A new trait arises in a population due to a mutation in a gene. In the case of asexual reproduction, this gene transfers into the next generation. If the gene is useful to the organism or does not cause any harm, then the gene stays in the population.
If the mutated gene harms the organism, gene slowly eliminates from the community.
If the gene neither gives benefit nor do harm, it stays in the population and multiplies as usual.
For example, in humans, sickle celled RBC’s arose due to a recessive gene mutation. It causes anaemia in affected people, but it remains in the population as it saves people from malaria.
A gene mutation is always random and non-directional. We can only predict the time of traits that do not have either benefit or loss. In such cases, a gene with a higher percentage in the population indicates an earlier onset.
So, here we cannot say anything.
Here, if the question tells both trait originated at the same time, then we can say that nature favors trait B or is against A.
In genetic studies, if we see a large percentage of a gene in a population, it indicates a natural selection favoring the gene and vice-a-versa.
Next: How does the creation of variations in a species promote survival.
See also: Solution of Heredity and Evolution Chapter 9.
