Humber Admissions Practice Test

What does microevolution refer to?

1. Change in the inherited traits in a population of organisms within a single species over time

2. Large-scale changes across multiple species

3. The process of creating new organisms in a lab

4. Random genetic drift in isolated environments

The correct answer is: Change in the inherited traits in a population of organisms within a single species over time

Microevolution refers to the small-scale changes in the inherited traits of a population of organisms within a single species over time. This concept is focused on the gradual changes that occur in a population's gene pool due to mechanisms like natural selection, mutation, genetic drift, and gene flow. These changes can lead to variations in characteristics within the species, enabling adaptation to environmental changes and influencing the overall diversity within the population. In contrast, the other choices describe concepts that do not align with the definition of microevolution. Large-scale changes across multiple species pertains to macroevolution, which addresses broader evolutionary changes that can lead to the emergence of new species. The process of creating new organisms in a lab involves biotechnology and artificial methods, which do not fall under the natural processes described by microevolution. Lastly, while random genetic drift can be a component of microevolution, it is just one mechanism amongst several others and does not capture the broader concept as effectively. Therefore, the definition focused on inherited trait changes within a single population is a precise characterization of microevolution.