Spandrel
Understanding Spandrels in Evolution
Language is an evolutionary adaptation. The cognitive mechanisms like memory, attention, categorisation, all have a clear evolutionary purpose. But once in a while we find a behaviour or attribute in an organism that lacks any clear evolutionary basis. This occurs when evolution propagates an adaptation for a particular reason and something else comes along for a ride: a spandrel. The term comes from architecture where a designer plans for a dome to be held up by four arches and you'll see space between the arches not because it was planned but because it is a by product of the design.
Many spandrels are put to such a good use that it makes knowing the fact that are they actually adaptations or not? Many artists used that space of spandrel make timeless beautiful art. Language is an adaptation music its spandrel.
Music as an Evolutionary Spandrel
Music is an auditory cheesecake. We didn't evolve a liking for cheesecake but we did evolve a liking for fats and sugars. We have a neural mechanism that rewards us when eating sugars and fats because in the small quantity available to our ancestors was beneficial for their well being. Activities like eating and mating are important for the survival of a specie. So they are also pleasurable to us because our brains rewards and encourages such behaviours. But we have learned to bypass the system to access those neural pathways for pleasure. We can eat foods that have no nutritional value, we can have sex without procreation, substances that exploit the normal pleasure receptors in the brain. None of these behaviours is adaptive but the pleasure centers don't know the difference. Eating cheesecake just happens to push pleasure buttons in our brains for fat and sugar. Music is simply a pleasure seeking behaviour that exploits one or more existing neural pathways that evolved to reinforce an adaptive behaviour - [linguistic communication]. Music pushes buttons for language ability, auditory cortex, and the motor control system that injects rhythm into the muscles while walking. Cosmologist John Barrow said that music has no role in survival of the specie and psychologist Dan Sperber called music an evolutionary parasite. Sperber believes we evolved a cognitive capacity to process complex sounds different in pitch and duration and this communication ability first arose in pre-linguistic humans. Music as per Sperber developed parasitically to exploit this capacity that had evolved for communication.