What scientific knowledge do we have that proves Darwin's theory?

Answer 1

Every theory in science is provisional. We don't believe in theories, we merely accept them as the best explanations available, subject to refutation in light of overwhelming evidence to the contrary.

The evidence supporting Darwin's theory of evolution is enormous, and we have added substantially to the collection over the past 150 years since Darwin's publication of "On the Origin of Species." The fossil record details changes undergone by species since amphibians first crawled out of Devonian seas. These amphibians bore uncanny resemblance to sarcopterygian lungfish of the same era.

Archeopteryx is a Jurassic fossil of a creature very much like a dinosaur, with numerous features of dinosaurs, but one key diagnostic feature of birds--it had feathered wings. We now know of dinosaurs that possessed feathers, which eliminated feathers as the primary diagnostic feature of birds.

Taxonomy is another over arching principle highlighting evolutionary relationships between species. The fact we can create a nested hierarchy of life forms strongly suggests ancestral relationships between species. If we could NOT construct such a tree of life, this would be evidence species had been created independent of one another.

In our own species, we have a variety of earlier ancestors and extinct "cousins." Peering more closely into our genome, we see enormous evidence of relationships, including shared broken gene sequences and endogenous retroviral insertions. These things should only hold true if common ancestry was the correct explanation.