The theory of evolution has never successfully predicted anything. Its success as a theory is attributable to its adaptability and its appeal to the wider public. That is why it has survived despite its failure as a predictive tool. Evolutionists will often argue that the theory has predictive value. They will come up with some predictions and 'hey presto!' our observations match those predictions. What they don't tell you is that the observations actually came first, then they thought up a way to explain those observations in evolutionary terms. Those explanations turned into predictions, but they can only predict the observations they were invented to explain.
There was of course one prediction made using the theory of evolution. It was predicted that the fossil record would show a smooth transition from species to species. The fossil record contradicted this prediction. The fossil record actually shows that species tend to remain the same for very long periods of geological time, then undergo a burst of rapid change (none of which is caught in the fossil record) then emerge as a completely different species. Being so adaptable, the theory of evolution was simply changed to match this observation. Thus, the current version of the theory of evolution can be successfully used to 'predict' trends in the fossil record.
The theory of evolution does not predict how well species should be adapted to their environment. Depending on how fast evolution occurs, how fast the environment changes, and how old the earth and life on it is, the theory could predict that all species will be perfectly adapted to their environment, or that our current lot of species are barely adapted at all and would go through tremendous, mind boggling transformations if only we could keep everything constant long enough for them to adapt. Or anything in between. Thus, no matter what we discover, the theory of evolution can be adapted to explain it.