What evolves during natural selection
• the proportion of different traits in a population
• entire species
• the phenotypes of individual organisms
All of the above - the proportion of different traits in a population, entire species, and the phenotypes of individual organisms - can evolve during natural selection.
Natural selection is a process in which certain traits become more or less common in a population over time as a result of their effect on survival and reproduction. The proportion of different traits in a population can change as individuals with advantageous traits are more likely to survive and pass on those traits to the next generation, while individuals with less advantageous traits are less likely to do so.
Over long periods of time, natural selection can also result in the evolution of entire species. This occurs when divergent selection pressures act upon different populations of the same species, leading to the accumulation of genetic and phenotypic differences that eventually result in the formation of distinct species.
Additionally, natural selection acts on the phenotypes (physical, behavioral, or physiological traits) of individual organisms within a population. As certain phenotypic traits confer advantages in terms of survival and reproduction, those individuals with these traits will have higher fitness and are more likely to pass on their genes to the next generation. This results in the evolution of the phenotypes of future generations of organisms.