Now you know
July 9, 2001
Contrary to Internet rumors, a duck's quack does echo - but it may not echo very well. Echoes occur when sound waves reflect off hard surfaces. Higher-frequency sounds reflect best, resulting in better echoes. Depending on the species of duck, its "quack" may lack high-frequency components - so the echo may be very faint.
(c) Copyright 2001. The Christian Science Monitor