Final answer:
The two central concepts of the modern theory of evolution are evolution itself—the change over time in organisms—and natural selection, the process where traits beneficial for survival become more common in populations.
Step-by-step explanation:
The two basic concepts that are central to the modern theory of evolution are:
- Evolution itself, which is the process by which organisms change over time due to changes in heritable physical or behavioral traits. Changes that allow an organism to better adapt to its environment will help it survive and produce more offspring.
- Natural selection, which is the process by which individuals with characteristics that are advantageous for survival in their environment are more likely to survive and reproduce. Over time, these advantageous traits become more common in the population.
These concepts form the backbone of our understanding of the biological diversity and the complexities of life forms on Earth. The framework laid out by evolution helps biologists make sense of the living world and guides them in predictions and experiments. For instance, the presence of a common ancestor explains why there are core characteristics conserved throughout different species. Through mutation and selection, the incredible diversity of life has evolved, each adapted to their unique niches and environments.