flock

Indian shepherds escort their flock of goats on a street in Kolkata, India, Friday, Jan. 31, 2014. Kolkata is the capital of the western Indian state of West Bengal located on the banks of the Hooghly River.

Bikas Das/AP

Herders escort their goats through a street in Kolkata, India

A murmuration of starlings fly close to power lines at sunset near Gretna on the Scottish borders.

Owen Humphreys/PA

A murmuration of starlings fly close to power lines at sunset near Gretna, Scotland.