For years now the growing resistance of bacteria to antibiotics has been claimed as evolution in action. However recent now show that antibiotics resistance existed long before the antibiotics were invented.
After studying the DNA in bacteria found in permafrost that had been dated to 30,000 years the researchers found the same set of genes that are responsible for antibiotics resistance showing that the predated the antibiotics. This shows that antibiotics resistance did not evolve in response to antibiotics but was already present in the population.
The net result is that antibiotics resistance can no longer be claimed as evolution in action. It does represent an shift in the population but not new information added to the genome but long existing information come into dominance.