ICMPC Day Two – Evolution

The evolution symposium was put together by Ani Patel, and included some of the most fascinating and cutting age papers from the field of “biomusicology”. In general biomusicologists are not interested in studying any particular style of music, but rather in the human capacity for music itself and in better understanding the biological basis that is shared among all musics.

1) First up was Professor Techumseh Fitch, one of my favourite speakers I have to admit. He started off with a really engaging introduction to the field which must have been brilliant for all the students for whom this may have been completely new territory. He talked about the development of biomusicology and his reasons for being interested in researching the musical capabilities of animals, whether they are our closest relatives or not. He stressed a need to look at evolution beyond the “Pleistocene era”, where our evolutionary lineage divided from that of the great apes. Instead insight can be gained from looking at far back into our ancestry. Second he suggested that a focus on adaption may be misleading – that we should not always be thinking about function as a reason for why something evolved. Rather we should also investigate trait development, mechanisms and phylogeny.

In looking at the cognitive skills that are shared among species we can notice two types of similarity. First HOMOLOGY; the traits we share with our closest genetic relative, namely the great apes. These are likely to have emerged through our common ancestor. Second CONVERGENCE; the traits we share with animals for whom our common lineage diverged many eras ago. These represent cases of parallel evolution and are more controversial (and therefore I suspect for Techumseh, more interesting!). They provide test cases for the question of WHY THINGS EVOLVED. He went on to discuss three examples of music evolution

i)                    Song – Apes have always demonstrated imitative skills, but never for song and speech, despite extensive training in some individual animals. Why? Tecumseh suggested that the key to this is certain cortico-vocal connections that are missing in apes. On the other hand a diverse and interesting group of animals have been shown to sing including, birds, whales, seals, bats, elephants and humans. One way to test the cortico-vocal theory is to determine if these animals all have this brain connection. So far we know that humans and a few species of song bird do….the rest of the tests are still to come.

ii)                   Drumming – This is apparently the only instrumental music demonstrated by nonhuman animals and it is only seen in our closest cousins, so African great apes (interesting not in Asian apes such as orang-utans). By studying drumming therefore we can build up a picture of our common ancestor.

iii)                 Dance – Capacity to extract the beat seems to be something we share only with parrots. Now there is some convergence for you! This area has fascinating insights to give about the nature of beat induction and why our two seemingly disparate species have evolved this ability. Ani Patel used to claim the answer for this was a vocal learning drive, but I suspect he has a new theory up his sleeve, as Techumseh doesn’t really talk about it here.

In conclusion, Techumseh suggested that the future of biomusicology is in studying the evolutionary roots of music in a productive and empirically rigid way.

2) The next paper was given in tandem by David Teie (composer) and Charles Snowden. They had a really fab idea for a study. They based their work on the finding a few years ago that Tamarin monkeys do not respond to human music. David and Charles made the logical argument that actually human music is composed by humans for humans, using tones from our vocal range and paced at our vocal tempo.  So maybe, Tamarins, who vocalisations are three times higher and faster than ours, need their own music composed for them. In other words, the research question was if you tailor music to the communicative features of the animal in question do you the get an affective response?

First they studied Tamarin vocalisations and came up with the characteristic features of high arousal calls and affiliative calming calls. David then composed music for his cello that contained features of these calls and that lay in the Tamarins frequency and tempo range for communication. They then pitted the two types of new ‘Tamarin music’ against human music that was either calming (classical pieces) or aggressive (bit of Matalica!). They measured a number of behavioural responses and found that, while the human music had little effect, the calming Tamarin music resulted in far more placid and relaxed behaviour than the aggressive music.

Based on their findings they argue that there are distinct music elements evident in Tamarin calls and these vary with context. When you create music with these structures you get a congruent affective response in Tamarins. Following this they speculate that Tamarin call structures might have evolved to communicate and induce emotional states, just as some argue is the case in humans (as in motherese spoken to babies)

3) There was a third talk in the symposium given by Hugo Merchent but I was a little tired from writing at this point to take down the finer details I am afraid, plus it was incredibly technical neuropsychology stuff showing monkeys ability to reproduce timing intervals. Sorry I don’t have more on that.

But the last talk was given by Ani Patel, and it was called the ‘social side of avian dance’.  This study was a much anticipated update in the studies of Snowball.  He is an example of the evolution of dance that Tecumseh alluded to earlier, and as expected Ani started by talking about the vocal learning hypothesis he developed based on his early work with Snowball and other parrots. He now appears to be developing this idea, as, on its own, it cannot explain the convergent evolution of dance in humans and parrots – why? Put simply, there are other vocal learners in the animal world that are not able to dance. So what else could be going on?

Ani speculated that maybe there is a social side to dance that plays an important role on evolution. Maybe species who communicate by moving in synchrony with a partner in a coordinated way as part of social bonding are the ones who have developed the abilities behind what we have labelled ‘dance’. So the hypothesis is that avian dance has an important social component – so Snowball should dance more when he is with his partner, his owner Irene Schultz.  And indeed a new study shows that to be true. Snowball dances about ~40% of the time to music when he is alone, ~65% of the time when he receives vocal encouragement but ~90% of the time when Irene dances with him. Striking numbers!!

They then tried a cool manipulation. Put Irene in headphones so some of the time she is hearing the same music as Snowball and some of the time she hears the same music but slowed down or speeded up 20%.  Who does Snowball dance with in the latter case? Ani showed two videos. The first, shot from the side, show Irene and Snowball happily dancing together. The second, shot from behind Snowball shows Irene wearing the headphones and dancing 20% slower than the music. To begin with Snowball dances with her, although in a muted way. Then, would you believe it, the little bugger turns round to face the camera and starts dancing to the beat! Everyone in the hall is laughing at this point. Then towards the end of the song he turns back round again and starts to dance with Irene’s beat while looking at her. This bird is a star. More studies need to be done but this is good evidence that there is an important social component to Snowball’s dancing, but he is not entirely immune to the beat when his partner is off it.

Again, a fascinating session. Biomusicology is a really small field right now, but a fascinating one. I would not mind a dabble in this area myself one day. I like the combination of background in depth scientific theorising, the development of clean testable hypotheses and use of inventive testing. We will see.