Darwin shared his theory of evolution by natural selection with the scientific community. However, his ideas challenged the idea that God made all the animals and plants that live on Earth, contradicting the commonly held Christian views of his era.
Despite the fact that Darwin had made many scientific observations and had a lot of evidence to support his theory, people struggled to believe him due to their beliefs. Darwin did not publish his scientific work and ideas until 28 years after his voyage in HMS Beagle due to the lack of support he received for his theory.
Darwin continued to discuss his ideas with like-minded scientists, such as Wallace. He developed his knowledge of geology and fossils to find more evidence to support his theory. His theory became backed by many years of experimentation and evidence, as well as other scientists coming to the same conclusion as him independently. Eventually, the theory of natural selection by evolution started to become much more well-known and accepted.
Since Darwin's theory was proposed, scientists have collected more and more evidence to support the theory. Although most people do accept the theory, some people still don't.