English Robins are forced to sing their song during the night. Not because they have figured out that music just sounds better in the dark, but because they can't compete with the noise we make during the day.
Research by Richard A. Fuller et al. has revealed that English Robins are active during the night in 18 out of 67 observed areas across Sheffield, England. In one area, an English Robin was only active during the night. As it turns out, there was significantly more (human caused) noise in those areas than in the 49 areas where the English Robin only sang during the day.
Where will this lead to? Maybe our 24/7 society will silence all English Robins and other birds during the day, forcing them to develop their nocturnal lives, which in turn will lead to sleepless nights for us, because we will be treated to midnight concerts every night.
Related post: Copypaste bird, Wild birds illegaly imigrating to city zoo, Flying penguins.