No. Speciation is not good enough. Mostly because it doesn't prove anything. If the evolutionary theory claims all life sprang from a single cell, but the only evidence is processes described in Genesis, then there really isn't any evidence for a single cell to produce every living being.
And since we "can't" observe that because the earth is "billions" of years old, then all we really have is speculation formed by opinions of scientists who don't want to accept the fact that God created the earth. Because the only way to prove He didn't would be to observe living beings well beyond our lifetime. And, conveniently, since they have posed the idea that the earth must be billions of years old, they won't ever have to really produce any evidence anyways.
Even though the idea of a billions old earth came from a misreading of geologic evidence left behind by the flood. Which caused pressure on the earth's surface that give current radiometric dating methods a skewed reading. Especially since a worldwide flood would have screwed with the atmosphere so much that the half-life of carbon would have been wildly different than we observe today, but we have no way of knowing what it used to be. So basing our assumptions about the age of the earth on misread dating "evidence" only gives a convenient excuse to never really have to provide real evidence of the evolutionary theory anyways.