Before one can decide that the theory of evolution is the best explanation of the present-day range of living material, one should examine all the implications that such a theory may hold. Too often the theory is applied to, say, the development of the horse, and then, because it is held to be applicable there, it is extended to the rest of the animal kingdom with little or no further evidence. There are, however, seven basic assumptions that are often not mentioned during discussions of evolution.
Many evolutionists ignore the first six assumptions and consider only the seventh.
The first assumption is nonliving things gave rise to living material, i.e. that spontaneous generation occurred. The second assumption is that spontaneous generation occurred only once. The third assumption is that viruses, bacteria, plants, and animals are all interrelated. The fourth assumption is that the protozoa gave rise to the metazoa. The fifth assumption is that the various invertebrate phyla are interrelated.