An international study, led by a researcher from Macquarie University, has found that goats can tell goat friends from goat strangers, by developing a mental image of how they sound and look.
The researchers say that goats could have evolved to use both sound and visual cues as a way to identify other familiar goats, much like we do with mental images of other familiar people, because they like to live in social groups. Dogs and horses also appear to have this ability.
"We observed that goats can differentiate between a call from their stablemate and a call from an unfamiliar goat, meaning that these animals are able to use sounds to help identify familiar goats," explained Dr Benjamin Pitcher, lead researcher on the study and research fellow at Macquarie University, who carried out the research at Queen Mary University of London.
"The results indicate that goats not only have an awareness of how other goats look, but also how they sound, meaning that they have a higher-level of cognitive ability in this aspect than previously thought," he added.
To test whether goats could identify the call of an individual goat, the researchers placed a "watcher" goat facing the pens of two "caller" goats – one pen containing a mate of the watcher-goat, and the other pen, a stranger goat.
"We played a recording of either the call of the familiar goat or the call of the unfamiliar goat at a space equally distant between the two caller-goats. We saw that the watcher-goat would turn and watch the goat who had made the original call, whether that be the stablemate or the unfamiliar goat, meaning that they could tell which goat should have made the call," Dr Pitcher said.
"When the watcher-goat was faced with two unfamiliar goats, however, it would show no preference to look towards one goat compared to the other."
The researchers say that goats could have evolved to use both sound and visual cues as a way to identify other familiar goats, much like we do with mental images of other familiar people, because they like to live in social groups.
"This higher-level of cognitive ability could be driven by their sociality, as there is growing evidence that social animals such as dogs and horses can also do this."
"By examining how different animals use sound and visual recognition, we can develop an understanding of how animals integrate information from multiple sensory sources, such as sight and hearing. This helps us to understand more about the complex world of animal communication,” Dr Pitcher concluded.[The Royal Society]