This is the season of music and dance in South India, and we have a veritable choice of a great variety of them — good and not so good. It is at this time that a debate has arisen in scientific circles about which other animals can sing — and do so for their own pleasure.
Of all animals on earth, only two sing: us and the songbirds. Not all birds but the group called songbirds. Chickens and doves, for example, do no more than simple vocalization, and their ‘song' repertoire is very limited. But a parrot or a hummingbird learns new ‘songs' from listening to others, as anyone who has a pet parrot knows. Of the 9,000 species of birds, over half of them are songbirds — able to sing new and involved phrases that they make on their own.
Ms. Vanessa Schipani writes in the 7 January 2011 issue of The Scientist , that Dr. David Rothenberg of the New Jersey Institute of Technology goes to the Pittsburg Aviary, housing 600 different varieties of birds, and plays his clarinet there. One bird in particular, the white-crested laughing thrush, starts singing with him, note for note and phrase for phrase. He says that he can communicate with birds this way because they both share a similar appreciation for music and beauty.
Schipani quotes Charles Darwin in this context. He wrote in “The Descent of Man” thus: “why certain bright colours and certain sounds should excite pleasure, when in harmony, cannot, I presume, be explained any more than certain flavours and scents are agreeable; but assuredly the same colours and the same sounds are admired by us and by many of the lower animals”.
Why do birds sing (or vocalize) at all? Conventional scientific wisdom is that they attract their mates for sex. Simple vocalizations, termed calls, are used to maintain contacts with others and to alert them about food sources or potential danger. Songs are more complex and longer in duration, with involved phrases. These are used to identify individuals, establish territory boundaries and of course for sex.
It is becoming increasingly clear that learning is required to produce complex songs. It is here that one separates a chicken from a nightingale. No matter what you play to a chicken, or what all it hears from its own tribe, it has a set of sounds that does not seem to increase. Its ‘music' is limited, primitive and inscribed in its DNA.
“Vocal patterns are hardwired in animals like chicken and frogs because they do not have to hear to be able to vocalize” remarks Dr. Ofer Tcernichovski, a New York-based scientist who is appreciative of what the music teacher David Rothenberg is doing.
A nightingale, the Mozart or MS Subbulakshmi among the avians, on the other hand, has over 200 different songs in its repertoire. And it can improvise. First it might sing the note sequence ABCDEF and a while later it might sing BEDF.
And when they sing in duets or in chorus, the “Jugalbandi” or “Savaal-Jawab” can be quite complex. It is here that science is not clear. While it is believed that a female might prefer a male with a complex and longer lasting song pattern than a ‘duller' one, is it always for mating or is there more to it?
This much is clear. Songbirds, just as humans, learn from listening and the younger ones learn and create more music than the older ones. Analysis of the brain circuitry (neuro-anatomy) of some songbirds shows a remarkable similarity with those of we humans.
The human brain is bilateral in structure. While the left hemisphere has zones connected with language, analytical processing, time sequencing and so on, the right hemisphere has regions governing musical ability, humour, visuo-spatial skills and so forth. And there is increasing evidence that such bilateralism is shared by songbirds, whales and higher mammals.
And among birds, why some can sing while others cannot is explained in part by their vocal anatomy. The sub-organ called the syrinx, its position and complexity set the songbirds apart. While enough research on the whale brain and vocal apparatus is awaited, the apes (gorilla, gibbon, chimp) have similar brain structure as ours but not the vocal apparatus.
Thus, while they cannot produce complex sounds and spoken language, they certainly have a sense of rhythm. As the musicologists Carl Sachs and Francois-Bernard Mache note, a group of gorillas can get together and vocalize in unison — the “gorilla chants”. And chimps can play simple beats of rhythm on tree barks.
Indeed, Dr. Mache notes that songbirds have a keen sense of rhythm. Some of them can compose songs with varying rhythmic patterns (kala pramanam), including ‘silences' of set duration (“Khali” as in Tabla playing). Why do they do all this? Not just for mating but for their innate pleasure and in aesthetic pursuit?
And what about dancing birds like the peacock? Do they do an avian version of Kathak? There is much that science can analyze on the origin of aesthetics in songbirds, whales and other animals.
D. BALASUBRAMANIAN
dbala@lvpei.org
