Rambling on 11 – what is sound good for?

Almost certainly unnecessary continuity note: held this piece until I’d written some more, but I haven’t. So posting now, and more follows on some other creatures that sing (“sing”?)

The last rambling posted here pointed toward what we can learn from the noises other creatures make that may resemble music. So let’s go into some biology a bit more. Hearing makes music possible. That highlights one of the special features of the senses that has developed in an astonishing way for this latecomer (evolutionarily speaking) to ways of gathering information about the world.

Any sense, I suppose, can be simply receptive – turning stimuli into signals. Most can also be used more actively. A creature with vision can scan for incoming photons. Some species also emit them: deep sea fish luring prey; fireflies seeking a mate. Chemical senses come to support a complex catalogue of signals. Cells make a huge array of chemicals all the time. Specialising to manufacture ones that can be released and pass a message to another organism is pretty common – in everything from insects to trees, not to mention pheromones in creatures more like us.

Sound, too, can be produced as well as detected. Bats, of course, navigate and track prey in flight by analysing echoes of ultrasonic frequencies that they emit themselves. And a host of other species make cries and calls that others can then hear. They, too, can be self-advertisement, threat, warning or…. Well, what?

Consider the primates, conventionally described as humans’ closest living relatives. They are a pretty vocal lot. Quite a few of them declaim freely, in their mostly high-pitched way. We all recognise the traditional imitation of a monkey, arms swung low, hooting gently?

The more elaborate forms of this get more interesting. Take gibbons. They have developed their vocal expression – a combination of panting and hooting – into something that researchers argue deserves to be called song. That is, they produce “a series of notes, generally of more than one type, uttered in succession and so related as to form a recognizable sequence or pattern in time.”

There’s more. Gibbons are monogamous, unusually for primates, and when coupled up they sing duets. They have slightly different male and female contributions, with bits of the “song” offered in turn. They are long and loud, says a review*, running for ten to thirty minutes (the author also reports hearing one male who got really into it, singing solo for 86 minutes!).

The calls apes and monkeys make are species specific, and appear largely inherited rather than learnt. The fascination about the duets some gibbons have developed so elaborately is the way they make communication by sound formation seem personal, even intimate. (Recorded examples of the gibbon duets seem hard to find, but if I track any down I’ll link to them later.)

 The review I’m looking at here is 20 years old, and there’s been a fair bit of work on which elements of music (or musicality) might be available to other species since, but the conclusion that the common ancestor of gibbons and humans made calls that formed the basis of what both do now seems reasonable. 

The author goes further: “It is tempting to assume that early hominid singing shared many characteristics with loud calls of modern Old World monkeys, and especially apes.” They might include being loud – the better to communicate over long distance – using pure tones, a small repertoire of phrases that are used repeatedly, changes in the speed of the calls, and what the scientists call “locomotor display” but regular folks recognise as dancing.

So, there’s a clue here that creatures a bit like us make sound that has some of the qualities of music to communicate. And so, probably, did their much older ancestors. 

And it seems unarguable that music now is being made to communicate. The question remains: what is it communicating, and how does that relate, if at all, to the more rudimentary communication that went on before? Is the gibbon duet a distant relative of the call and response that crops up in many musical contexts, for example? Maybe. And what other species offer musical precedents? More on that to come.

* Thomas Geissmann, Gibbon Songs and Human Music. In Wallin et al, The Origins of Music, MIT Press, 2000

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s