I came across this article from Conservation Magazine yesterday, albeit a couple years old, but it's very interesting. The article is about birds incorporating human noises into their vocal repertoire.
A male European blackbird was terrorizing the neighborhood. For
several months, he started singing at around 5 a.m. each day, but this
was no ordinary song. The bird imitated the sounds of ambulance sirens
and car alarms at a jarringly life-like volume. It even produced
cell-phone ring tones that went unanswered for hours.
The tale of the annoying blackbird in Somerset, U.K., was not unique.
Hans Slabbekoorn, an assistant professor of behavioral biology at
Leiden University in The Netherlands, had heard similar stories—but he
was skeptical that such bizarre reports could be true. So he started
asking people to send him recordings of the off-kilter blackbirds. Sure
enough, what he got back was pitch-perfect imitations of urban noises,
including not just sirens and car alarms but even the distinctive sound
of a golf cart backing up—mimicked by blackbirds living near a golf
While the sounds seemed artificial, the reason birds were making them was surprisingly natural....continued here.