Brian Thomas at ICR reports that “100 Years of Fruit Fly Tests Show No Evolution”:
Fruit flies, with their short generation times and only four pairs of chromosomes, presented prime testing ground for evolution. In laboratories worldwide, they have been subjected to all manner of mutation-inducing phenomena, including hosts of chemicals and radiation treatments, to try and accelerate evolution-mimicking mutations. After all this, fruit flies should have certainly exemplified evolution by now. But they haven’t.
…. mutating (through substituting, deleting, or duplicating) developmental genes like HOX has only ever yielded a dead fly, a normal fly (if the mutation happened to have no noticeable effect), or a tiny monster. None of these results match the “positive improvement” expected of Darwinian evolution.