From livescience.com:

For the first time scientists have observed in real-time evolutionary changes in one species driven by competition for resources from another.

In a mere two decades, one of Charles Darwin’s finch species, Geospiza fortis, reduced its beak size to better equip itself to consume small sized seeds, scientists report in the July 14 issue of the journal Science.

The finch once had its own kingdom on the Galapagos Island of Daphne Major. It had its pick of seeds to eat. But the arrival of another species of finch about 20 years ago, and additional food competition from a drought on the island in 2003, changed everything.

Here are a few observations:

• This is not the first time that natural selection has been observed among the famous finches on the Galapagos Islands. Finch beak sizes have been observed to change from year to year with variations in rainfall. What is significant this time is the competition between species that was involved.
• This demonstrates microevolution, but doesn’t demonstrate macroevolution. I’m not even saying that there is no such thing as macroevolution, only that this does not prove in any way the concept that micro + micro + micro + micro… = macro.
• This will be, in my mind, a non-issue in the creation/evolution/ID debates. As far as I know, none of the young-earth creationist organizations would dispute that this type of natural selection and microevolution occur.

Grace and Peace