There is a very interesting take in Slate on the reliance of Mouse Models in biomedical science. You can see the temptation in a fast growing animal that elicits limited sympathy from the general public. But the concern with missing key drugs is real -- especially when the diseases in mice operate differently than in humans.
But the real kicker was the discovery that control mice are overfed, under-stimulated and obese. This puts an entirely new spin on studies that restrict caloric intake. They may be saying that eating a normal diet is life enhancing and not caloric restriction. These sorts of blind alleys can have enormous consequences.
Go and read -- it is worth it.