When new evidence shatters a previous assertion, the old belief is dropped or modified. No such setbacks have hit the theory of evolution. After 140 years of research, virtually the entire scientific world now agrees that evolution is a fundamental aspect of nature. Complex animals and plants arose from earlier, simpler ones, over hundreds of millions of years. The fossil record shows it.
Geological strata show it.
Radioactive dating shows it. The incredible diversity of species, with variations in different locales, shows it. The uncanny similarity of organs, bones, fluids and nerves in many animals shows it. Evolution was proved when skimpy Indian maize was improved into today's nutritious corn. It was proved by the clear fossil record that today's horse grew from a tiny precursor.