What were the original working tasks that shaped the Australian Terrier's tendency towards vocalization?

Answer

Pest control and alerting owners to intruders on farms.

Their background required them to be useful in dispatching vermin and signaling danger or the successful hunting of rats, necessitating alertness and communication.

What were the original working tasks that shaped the Australian Terrier's tendency towards vocalization?
DogbarkAustralian Terrier