What is the theory of evolution by natural selection about?

The theory of evolution by natural selection is fundamentally about the process through which species adapt over time based on variations that enhance their chances of survival and reproduction. This mechanism occurs as individuals within a species exhibit differences in traits. For example, certain traits may provide advantages in finding food, evading predators, or thriving in specific environments.

Over generations, individuals carrying traits that favor survival tend to reproduce more successfully, passing these advantageous traits to their offspring. This process leads to a gradual shift in the overall characteristics of the population, ultimately resulting in the evolution of species.

This understanding is rooted in Charles Darwin's observations, where he noted that environmental pressures influence which individuals are more likely to survive and reproduce. By focusing on the variations that support survival in changing environments, the concept emphasizes adaptation as a key component of evolution.