The theory of evolution by natural selection

The theory of evolution by natural selection explains how species change over time. It suggests that individuals within a species vary slightly in their traits, such as size or speed. Some traits help an organism survive and reproduce better in its environment. These advantageous traits are more likely to be passed on to the next generation. Over many generations, this process leads to gradual changes in the species, sometimes resulting in new species. Natural selection is like a filter that favors the most beneficial traits, shaping the diversity of life we see today.