You're begging the question...
Where is the observation or evidence of random spontaneous mutagenic speciation?
That was before science existed. 95% of all scientists who ever lived are still alive today, science is that young. Science is nothing more than a methodology. It does not champion truth, only data and predictions made therefrom..
One time it was considered truth that the world was flat since science could not prove otherwise.Contrary to popular impression, Aristotle and later Hellenistic scientists believed that the earth was spherical. The battle over whether the earth was flat was waged at the time of Socrates, and the flat earthers lost out. In the middle ages, in the depth of the dark ages, some thinkers tried to revive a flat earth theory, but certainly over the past couple of thousand years its been the dominant view that the earth is spherical.