Problem is, in the question of how did the biodiversity we see around us come to be, there really isn’t a competing theory to evolution. There are hypothesis (like the laughably termed “Intelligent Design”), but no other real theory.  There is just simply too much evidence for evolution. It really is overwhelming.  There is a lot more to debate about in how life started on this planet. Was it a primordial soup of molecules that just happened to be at the right place, at the right time? Did life arrive on this planet via some simple biological molecules buried inside a meteor? Was life as we know it created by a previous life that lived on this planet? Was life as we know it created by an extra-terrestrial intelligence of some kind or another? But why we have such biodiversity, on how life is the way it is around us, the evidence is so overwhelming for evolution, that if it is not true, the truth cannot be significantly different.

The problem with that is that creationism isn’t actually a theory at all. A theory is an idea that explains a fact. We call the “theory of evolution” a theory because it’s the information we use to help explain how the fact of evolution works. Religious beliefs aren’t theories OR hypothesis by any measure of the scientific theory, they’re completely subjective opinions based on entirely non measurable criteria.