This is a nice observation. Hopefully this will serve as an eye-opener to people who refuse to accept the fact of evolution.
Yeah, this observation is actually pretty old, and it hasn't made a splash for the reasons Indi gives. The important thing that scientists are looking for is evidence of complete reproductive isolation. Theoretically, the formation of species goes like this:
1) Two populations of a species get split somehow
2) That split causes them to stop mating with one another for whatever reason (in the example given, flies feeding on different fruits mate at different times, so flies born on apples never get to have sex with flies born on hawthorn berries)
3) Microevolutionary mutations accumulate, either randomly or due to different selective environments
4) Enough mutations accumulate that the separated populations can no longer mate, even if they are suddenly able to start mating again (the apple flies start meeting hawthorn flies in bars again but cant mate successfully or have dead or infertile offspring)
5) Now the permanently isolated populations are free to diverge as much as they 'want' and its easier to understand how 'macroevolutionary' changes could happen.
At point 4), the populations become permanently reproductively isolated, and speciation (under some defiinitions) is said to occur. The underlying mechanisms behind this process are complicated, and theory is currently under revision. We don't understand how long it takes to go from step 3) to step 4), but it could require thousands or millions of generations.
Therefore, we haven't directly observed speciation events ('macroevolution') in outcrossing animals (but we HAVE in plants, where it can be faster and more cut-and-dry for several reasons). The significant thing will be to see if, when, and how the apple maggots and hawthorn maggots get permanently isolated.
Good old flies. Showing the way for the rest of us and evolving like crazy. Go flies!
I dont think I have enough reasons to believe in evolution
I find evolution absolutely fascinating. Whether small or large changes, it still is very exciting to be part of it. But can also understand that for biologists who have worked with this for most of their lives, this must be slightly boring. Just sad that some of the species such as chimps are "endangered" and I sometimes wonder whether that should be a sign for us to look out for human species? Our immune systems aren't as strong as they used to be, our environment is not as robust as it used to be and cannot survive all the hammering of contamination. I can imagine we will be seeing even more of the "small changes" to evolution, as a response to adapt to the contamination of the environment it is trying to survive in. Perhaps salmon will find a way to make changes with regard to all the poisons it has to absorb in the ocean? Either that, or it may die as well.
