Is The Human Species Still Evolving?

Is there a Homo superius just around the next corner, waiting to take our place? Let's think about what it would take: If we were to give rise to a new species, something would have to happen to us to create a bottleneck or isolated place for a founder-person and her or his mate to show up and get separated from you and me and our offspring.
In the modern world, that is very unlikely. We have airplanes and ships and the Internet. When human populations are even a little bit separate, they start talking differently. Other bigger changes might happen with more profound separation. Perhaps this could happen somewhere beyond Earth, even, such as in a colony on Mars.