It has been a well accepted maxim of anthropology that humans stopped evolving about 50,000 years ago due to increasing adaptions through cultural change rater than physical. However, recent DNA research has shown that the rate of human evolution is actually increasing. Researchers theorize that this is due to a combination of the fact that cultural change adds to natural selective forces and that an drastically increasing human population provides a much larger pool in which positive mutations can develope. Mathematical modeling of evolution indicates that contrary to intuition it does not take much longer for an advantageous gene to spread throughout a much biger population. This work is covered in more detail in "The 10,000 year Explosion".

We may not survive 100,000 years because we will be replaced by the something like the docile four toed nebish of Scifi capable of living peacefully in massive megacities.

The thought that humans evolve to live in their culture is somewhat scary though given the nature of some cultures in the world.

I believe humanity will have descendents in 100,000 years but they may be very different than us. They could be vastly more intelligent cyborgs in an advanced technological society or significantly less intelligent hunter gatherers in a resource depleted world. They could appear very similar to us on the surface yet be far more capable of living peacefully and cooperatively in large groups. They might have phenomonal immune systems to deal with extremely crowded living conditions and adapted to the diets that currently cause heart disease and cancer.

We can't stop evolution although we may eventually exert some control over it. The best ways to make sure we have descendents far into the future is to develop sustainable forms of technology and government, as well as spread beyond Earth.

Regards,
Mark