Urban Birdsong vs. Traffic Noise

Cities are not silent for the animals adapting to live in them, and few adaptations are as measurable as the acoustic arms race between songbirds and traffic. This simulator renders a 3D city street where a bird perched in a curbside tree sings while a stream of cars sets a rising floor of low-frequency masking noise. Real sound-propagation physics — spherical spreading, frequency-dependent air absorption, and a traffic spectrum that fades toward high pitch — combine into a live active-space radius: the real distance the song can still be heard above the noise. Push the traffic slider up and watch that radius collapse; raise the song's pitch (or hit auto-adapt) and watch it partially recover, exactly the trade-off that drives real urban birds like great tits and robins to sing measurably higher near busy roads than their rural relatives.