Which mechanism is primarily responsible for the differential reproductive success in a population?

Which mechanism is primarily responsible for the differential reproductive success in a population?

• A. Natural selection
• B. Gene flow
• C. Genetic drift
• D. Mutation

Answer: (A)

Natural selection is the mechanism primarily responsible for differential reproductive success in a population because it involves the process where individuals with certain phenotypic traits that are advantageous in a given environment are more likely to survive and reproduce than those without those traits. This leads to an increase in the frequency of those advantageous traits in the population over generations, ultimately shaping the evolution of the species. The concept of fitness in evolutionary biology is central to natural selection; it describes how well an organism is suited to its environment, effectively measuring its ability to survive and reproduce. For example, in a population of birds, individuals with beaks that can more effectively access food in their environment are more likely to thrive and pass on their genes. Over time, this leads to shifts in the population’s genetic makeup as advantageous traits become more common. While gene flow, genetic drift, and mutation play important roles in the evolution and genetic variability of populations, they do not have the same direct impact on reproductive success as natural selection does. Gene flow involves the movement of alleles between populations, genetic drift refers to random changes in allele frequencies, and mutation introduces new genetic variations, but none of these processes directly relate to the concept of fitness and adaptative success as clearly as natural selection does.

Natural selection is the mechanism primarily responsible for differential reproductive success in a population because it involves the process where individuals with certain phenotypic traits that are advantageous in a given environment are more likely to survive and reproduce than those without those traits. This leads to an increase in the frequency of those advantageous traits in the population over generations, ultimately shaping the evolution of the species.

The concept of fitness in evolutionary biology is central to natural selection; it describes how well an organism is suited to its environment, effectively measuring its ability to survive and reproduce. For example, in a population of birds, individuals with beaks that can more effectively access food in their environment are more likely to thrive and pass on their genes. Over time, this leads to shifts in the population’s genetic makeup as advantageous traits become more common.

While gene flow, genetic drift, and mutation play important roles in the evolution and genetic variability of populations, they do not have the same direct impact on reproductive success as natural selection does. Gene flow involves the movement of alleles between populations, genetic drift refers to random changes in allele frequencies, and mutation introduces new genetic variations, but none of these processes directly relate to the concept of fitness and adaptative success as clearly as natural selection does.