OK, show us a speciation event that you know God influenced?
I don't have to, since I have not made the "God did it" argument. I have simply pointed out that a "rational theist" such as yourself has no logical grounds for ruling out the possibility that God could do such a thing. And yet you have done so, apparently on a global basis -- which represents a very significant assumption on your part, about the way the world runs. Can you not simply acknowledge that assumption?
What I have done, is argue for the efficacy of intelligent design as a valid hypothesis. On that score, I can show you many instances of intelligent design: the dogs and cats in your neighborhood, the wheat in your bread, and various genetic manipulations being some that should be immediately familiar to you.
The true fact of this sort of intelligent design points out a weakness in the question you've posed. We know, because we've done it, that human intelligence explains significant characteristics of many familiar life forms. And yet I doubt that you could pose a scientific test to detect this human involvement, because the paradigm within which you're working is based on an assumption of natural processes, not processes guided by intelligent agents.
It would be folly to argue against the presence of natural processes in the development of life -- that would indeed be to blind myself to the evidence. However, the data before us demonstrate that, for at least as long as there have been humans, that natural processes are not the only factor at play in the development of life -- intelligent agents have had an influence as well.
So you're faced with a problem: you have a theory that does not explain -- indeed, assumes away -- something we know to be true: that intelligent agents can and have influenced the development of life on Earth. It's a weakness in your hypothesis. I'd go so far as to call it an unacknowledged bias.