A viable scientific theory should be able to predict what will happen in the:
1) Past.
2) Present.
3) Future.
I guess that blows probability and chaos theory out of the water then.
We may not be able to make specific predictions about what mutations will occur and what traits will survive, but this isn't where the predictive power of evolution lies -- though we can say with some certainty that any diseases will become resistant to any new widely used antibiotics.
These predictions do not have to be about things happening in the future. They can be "retrodictions" about things from the past that we have not found yet. Evolution allows innumerable predictions of this sort. For example:
Darwin predicted, based on homologies with African apes, that human ancestors arose in Africa. That prediction has been supported by fossil and genetic evidence.
Dawrin also predicted that a mechanism would be found which drives the changes in heritable traits over time; that mechanism is DNA.
Tiktaalik: A Case Study in Scientific Prediction (scroll down to p.7, though the rest of the info there is good too):
Using the principles of evolution, scientists have been able to predict what new fossils might be discovered. For example, scientists had found fossils of ancient fish tha lived in shallow waters in earlier times and fossils of four-limbed land dwellers that appeared in later time. What happened in between?
Evolutionary theory predicts that there would be one or more creatures with characteristics of both the ancient fish and the later land-dwellers. A team of scientists decided to look in sedimentary rock in northern Canada that was deposited about 375 million years ago, about the time these intermediate species were thought to have lives, based on other evidence from the fossil record.
In 2004, the team found what they had predicted: the fossil of a creature with features of fish (scales and find) and features of land-dwellers (simple lungs, flexible neck, and fins modified to support its weight). The bones in the limbs of this fossil, named Tiktaalik, resemble the bones in the limbs of land-dwelling animals today.
By understanding evolution, scientists were able to predict what type of creature existed and in what geologic layer it would be found. The discovery of Tiktaalik fills another gap in the fossil record.
In other words, we can make predictions about faunal succession and look for fossils which match those predictions. Here is a case where we've found one.
Tell me, can you think of any predictions that creationism makes?
