Language is something unique to humans; but look hard enough and you can find some of the core components present in animal communication. The "language gap" between us and the rest of the animal kingdom isn't as big as it first appears.
This week was a jaw-fully good one for human evolution; but our ape relatives have gotten a boon of their own. Two recently published studies have further closed that language gap, revealing an orangutan that makes some rather human-like noises 1 and chimps that communicate quantities 2.
Counting chimps
Chimps are actually pretty good at maths (at least, basic maths), matching human performance 3; and sometimes even beating us. And if you've ever been to the zoo you'll know chimps can make an awful racket. But have these two chimp abilities ever combined? That's something primatologists have debated for a while.
There have been some cases of captive chimps apparently communicating quantity; but researchers wanted to see if it was present in wild chimps. So they went out into the jungle and documented chimps for a combined 750 hours, discovering that - as my introduction revealed - yes they do. Wild chimps give a call when they find food; but change the call based on what kind of food it is and how much is present, with lower noises indicating higher amounts of food 2.
The fact they have "names" for different foods and communicate quantity confirms that chimp language is more complex than we thought. But more than that it means chimps have specific conversations about specific objects. That's an under-rated but key component of any language.
Roll up, roll up. See the great talking orangutan
I hate to lead you on dear reader; but contrary to what the subheading suggests this isn't the story of a talking orangutan. Rather, this is the story of Tilda the orangutan who spent most of her life in human captivity. During this period she learnt many human-like behaviours, including whistling, clapping and waving 1.
She also makes a series of rhythmic calls when she wants the attention of humans (typically during feeding time, to ask for more food). This might not seem like the most impressive of Tilda's tricks, but it is still interesting. These calls have the same rhythm and speed as human speech; and involve many of the same muscle movements. Moving the mouth at that speed and with that much control is unusual for apes, and outright unknown in orangutans 1.
Could this be Tilda trying to mimic human speech? Maybe, but that's not what makes this story interesting. Rather, it's the fact no "extra" evolution was needed for this to be possible. Tilda is still a regular orangutan. This implies that a good portion of speech could develop before any evolution for speech occurred. Ape vocal cords are good enough to get the ball rolling.
It might also shed some light on what that early speech was like. Perhaps, like Tilda, rhythm, speed and pitch were the important components. Could early speech have been almost musical in nature? It's hard to draw conclusions from one example, but I can almost hear the cavemen singing.
References
- Lameira AR, Hardus ME, Bartlett AM, Shumaker RW, Wich SA, et al. (2015) Speech-Like Rhythm in a Voiced and Voiceless Orangutan Call. PLoS ONE 10(1): e116136. doi:10.1371/journal.pone.0116136
- Kalan, A. K., Mundry, R., & Boesch, C. (2015). Wild chimpanzees modify food call structure with respect to tree size for a particular fruit species. Animal Behaviour, 101, 1-9.
- Cantlon JF, Brannon EM (2007) Basic Math in Monkeys and College Students. PLoS Biol 5(12): e328. doi:10.1371/journal.pbio.0050328
