Holly Root-Gutteridge at Aeon Magazine:
After hundreds of hours listening to thousands of wolves for my PhD, the difference between howls was obvious. The voice of a Russian wolf was nothing like that of a Canadian, and a jackal was so utterly different again that it was like listening to Farsi and French. I believed that there must be geographic and subspecies distinctions. Other researchers had made this proposition before, but no one had put together a large enough collection of howls to test it properly. A few years later, my degree finished, I told my Dracula story to the zoologist Arik Kershenbaum at the University of Cambridge. He promptly suggested we explore how attuned to wolves I really am. Are there differences between canid species and subspecies and, if so, could these reflect diverging cultures?
When animals call to each other, they are communicating in a single stream of information from caller to listener. Until modern recording technology was invented, any acoustic communication lasted only as long as the echo.
more here.