Geoffrey Lean, the hard-pressed environmental correspondent of the Telegraph, has come
in for some stick again.  He published

Rubbish saves birds, a major study finds

And this was typical of the replies.

Gosh! Incredible scientific insight. Animals thrive better where food is readily
available.
Deserves a Nobel Prize for the bleedin' obvious.

But in science, methinks, the obvious does not always follow.  Here, from the website of Ohio State University, is part of the news item (in full here):

COLUMBUS, Ohio – While birds living in urban areas face more predators than do those in rural areas, that doesn’t mean urban birds face more danger from nest robbers.

A six-year study conducted in 19 central Ohio forests from 2004 to 2009 found that, as expected, rural areas that had higher numbers of nest predators such as raccoons, domestic cats, and crows, also showed lower rates of nest survival.

But there was no relation between the number of predators and nest survival in more urbanized areas.

Researchers believe that’s because nest predators in urban areas have access to more human-provided food, making them less likely to prey on nests.

Here’s the abstract of the article, rather technically worded.

Now as for meine eigenen Gedanken, however much food is available, there will come a saturation point where the population will not increase.  If not predation in the nest, what is keeping the bird numbers down?

So two questions.  (1) What do you all think of this study?  But more important (2):

Can you think of other examples of where the natural world (or science in general)
doesn’t follow common sense, or the obvious?