God said that it was "good" at Creation.....If something was struggling in some sort of primordial slime since the beginning, struggling in the "survival-of-the-fittest" conflict, then why would it be good? It wouldn't. It would be good if created in perfection as-is.
And he answered and said unto them, Have ye not read, that he which made them
at the beginning made them male and female,
Matthew 19:4
And God saw every thing that he had made, and, behold, it was very good.
Genesis 1:31