flies

When I bought my new LCD computer screen,
a strange thing happened.

It was summer, windows opened,
and many flies would seat on top of it,
filling it up with their dirt.
For a moment I thought I had a burned pixel,
but no, it was fly's dirt.

Anyway, the strange thing is
that I never had such a problem,
with my old tube screen.
And I look at my small tube tv,
and flies don't even go close to it.

What's the matter?
I can only assume that flies
can detect the radiation of the tubes,
and therefore they avoid those screens.

Conclusion:
flies are smarter than humans