"Scientists seeing 'profound' evolutionary impact from human handouts."
Note that the article takes no stance as to whether it's good or bad to feed the fluffy friends. It merely remarks that the feeding that is done has had an observable effect in changing the bird populations - and the birds themselves - seen in particular places.
It suggests that "watchers" should be alert for similar changes in populations of visitors, even over fairly short spans of time.
Perhaps some of our own observers have seen suspicious evidences of "different" visitors over a time in their own places of observation and might have comments?