How can mutations and natural selection work to create the amazing complexity of life in our world? It doesn't add up. The first problem we find is that the variations we see in microevolution are always within limits set by the genetic code. Fifty years of genetic research on the fruit fly have convinced evolutionists that change is limited and confined to a defined population. Despite being bombarded with mutation agents for half a century, the mutant fruit flies continue to exist as fruit flies, leading geneticists to acknowledge that they will not evolve into something else. This confirms Gregor Mendel's findings in the 1800s that there are natural limits to genetic change. Genetics professor Francisco Ayala is quoted as saying, "I am now convinced from what the paleontologists say that small changes do not accumulate. Small changes aren't the only thing that doesn't add up. But more importantly, the amount of change isn't really the issue.
Mutations can only modify or eliminate existing structures, not create new ones. Within a particular type of creature, hair can vary from curly to straight, legs can vary from heavy to thin, beaks from long to short, wings from dark to light, etc. But the creatures still have hair, legs, beaks, and wings-nothing new has been added.
What interests me is that modern fruit flies must have had ancestors. The earliest known fossil flies (Diptera) come from the Middle Triassic (about 240 million years ago); since modern flowering plants didn't evolve until the Early Cretaceous (about 140 million years ago), the first fruit flies must have evolved in Cretaceous times or later. From this, it follows that the Jurassic and earlier ancestors of fruit flies were not themselves fruit flies, and the Palaeozoic ancestors of Diptera were not themselves Diptera.
Of course, you can argue that the non-dipteran Palaeozoic ancestors of Diptera were still insects, and that they had wings, legs, hair, eyes, mouth-parts,
etc., and that therefore nothing new has been added in the evolution of Diptera and fruit flies from earlier orders and families of insects. However, the same argument can be used for the evolution of birds from dinosaurs (which had four limbs, feathers, hearts, lungs, brains, eyes,
etc), and for the evolution of humans from earlier species of apes. At what point do you say that something new has been added, something that could not have been obtained by the modification of an existing structure?
