Are there really enough differences between human speech and the vocal communication of other animals to say that language is a purely human ability?
Do animals have linguistic abilities comparable to those of humans? This is a question which has provoked a lot of contentious scientific debate, and the one which I am investigating for my thesis. It fascinates me, both from a purely scientific and physiological approach looking at the brain structures involved in spoken language to the philosophical debate on animal awareness. Painting pet portraits on commission I have seen many different attitudes of owners towards their pets; many of whom raise domestic animals in the same way as they would raise a child.
As a zoology student, however, I hope to avoid anthropomorphising and to look objectively at the studies so far carried out investigating vocal communication in animals – from those in the wild to controlled investigations with trained animals. Many questions have been answered and (as is often the case) many more raised. But as a general pattern in the literature, linguistic abilities traditionally thought to be uniquely human traits are being attributed more and more to other species.Alex the Parrot, trained in studies by Irene Pepperberg, is a key example, as well as Akaekamae the dolphin, Kanzi the bonobo and Washoe the chimpanzee. Many examples were found suggesting that these animals have a capability for the understanding of syntax, and could apply it in novel contexts. Often this occurred without prompting, an example being the final words of Alex to his trainer: “You be good. I love you.” The fact that many animals also use vocal communication for the same reasons as humans also suggests that it shares a common evolutionary origin. Many of the same brain regions are involved in vocal learning (The regions Broca and Wernicke being some of the most studied), and in fact certain types of sounds tend to have the same effect regardless of the species.
According to Owren and Rendall, abrupt noises with erratic frequencies directly affect certain neural pathways in the brain. The listener’s attention is immediately shifted from their current activity to the source of the sound, and they may become alert or alarmed (in both of these cases it increases activity). The alarm calls across species tend to be structurally very similar; and all designed to create an instant and urgent reaction in the listener. The opposite effect is seen from continuous sounds, gradually moving from a high to a lower pitch. These have an almost universally ‘calming’ effect across species, decreasing mental excitement and tending to reduce activity.
It is certainly the case that in many cases where animals and human interact, a certain level of mutual understanding can be reached. Those who interact with livestock make good use of different whistles and clicks to control and coordinate their charges. For children with learning difficulties, interaction with animals has been found to be of huge benefit (a good example of this being Riding for the Disabled). Even children who have difficulties in communicating by the use of human language share a common ability to relate to animals.
I would argue that language in general has a common evolutionary origin closely linked to social living, and that with a diverse range of different structures for sound production, animals make use of vocal signals for many of the same functions as humans. Another of these would be courtship, with the songs of birds as well as whales being key examples (among many other species). Song in many species also functions as territorial defense, analogous to the national anthems of humans. Birds sing to advertise their fitness and ability, if necessary, to fight off other males; national anthems not only define ‘territory’ but are equally sung before sports competitions where players compete to display their fitness and skill against rivals.
So despite a classical view that animal vocal communication can teach us very little about human language, I believe they share a lot more in common than might have been previously thought. The study of vocalizations in different species could bring to light key features in the evolutionary history of human speech.