it also is sterile. Therefore, how could the macro evolutionary process advance?
The same way the "microevolutionary" process does.These changes are happening to the entire population as these very small changes add up you end up with new species.
You agree "microevoultion" happens correct?
These small mutations are too small to cause problems with reproduction and over time these small changes add up. Evolution doesn't happen in jumps. One population is cut off from the other and the entire new population evolves.