Why did the hedgehog NOT cross the road? Because it had adapted its behaviour in order to thrive in a threatening man-made environment
Blackbirds: Noisy town life has changed this bird's tune, literally. The frequency of the bird song increases with the background noise. The average maximum frequency of the inner-city bird, where background noise levels average 66 decibels, is 3165Hz, compared with 2657Hz in the surrounding rural area where noise levels average 37 decibels.