The fact that the events themselves happened in the past is irrelevant. You can still make predictions and test them by finding fossils, studying the earth, etc. The theory allows you to predict the results of expirements regarding where fossils are found, what ages they are, etc. Even though the events that laid out the fossils are in the past, the experiments are in the future.
Also, when scientist talk about evolution, they usually refer about the process of life changing. On the other hand you are referring to the specific example of evolution as it hapened on Earth. The reason I'm making this point is that when someone says that they don't believe in evolution, a scientist will interpret that as them being opposed to the whole theory, where they really sometimes just mean that they don't believe life on Earth evolved.
The difference is that, while specific events of evolution such as the descent of man are in the past and cannot be reproduced in the present, evolution in general (like the evolution of microbial resistances) is observed in the present all the time. Even many of the evolutionary events observed today may not be reproducable are ordinary events, they are reproducable as a catergory.