All of the historical sciences - evolution theory, anthropology, archeology, Egyptology - deal with a very spotty historical record. Moreover, they fit individual finds into a blueprint theory which is in effect more of a paradigm than a theory as compared to physics, etc.
If complete remains of every creature that ever lived were available to the investigators, sequenced serially, then the underlying paradigm could be subjected to rigorous tests on a confidence par with physics.
As it is, belief is required. For some, belief in the paradigm. For some, belief in God - with of course, a wide range of understanding of both Scripture and the paradigm. Some one, some the other, some both.
Or, one could investigate how self replication could arise via chemistry, as more and more researchers are doing. Anything written on the subject that is more than a couple of years old is not authoritative.