Birds singing different tunes in lockdown

The skies do sound different during the pandemic, as many have noticed, and indeed, birds are singing different tunes during lockdown, according to a scientific study by the University of Tennessee in Knoxville. By analysing the calls of sparrows recorded over decades, scientists confirmed a change in the birds' vocal repertoire when the city fell quiet, Science Alert reports. The birds upped the quality of their songs, as they called to defend their territory and entice a mate. The sparrows also sang more quietly.