In a twin submission, Mehr, Krasnow, Bryant, and Hagen and Savage et al. offer two interesting yet very distinct accounts for the evolution of human music and musicality. Before we dive into the evaluation of these different proposals, it is worth to clarify what is music, that is, what needs to be explained. Human music is a unique communication system unmatched in nature. We can communicate the whole range of human emotions with music, we can signal our commitment, our attention, intentions, we can coordinate work with music. Music relates to animal “song” similar to human language relates to the “language of the bees.” Interestingly enough, the species that evolved this unique communication system also evolved another unique communication system: human language.
It is hard not to notice the similarities between ideas proposed to explain the origin of human language on the one hand and music on the other hand. All the functions discussed by the two groups were proposed to explain the origin of language, as well. Famously, the “by product” theory was proposed by Chomsky and colleagues (Hauser, Chomsky, & Fitch, Reference Hauser, Chomsky and Fitch2002), perhaps even more famously the “vocal grooming” theory was originally proposed by Dunbar (Reference Dunbar1993) in the context of language evolution, the signalling of mate quality was proposed by Miller (Reference Miller2011), bonding of female coalitions was proposed by Knight (Reference Knight1998), and finally bonding between mother and her child was proposed by Falk (Reference Falk2004) as a selective force to explain the evolution of human language (see Számadó & Szathmáry, Reference Számadó and Szathmáry2006 for a review).
The similarities do not end here. Both fields aim to explain the origin of a unique communication system found only in humans, both fields aim to recreate a series of events that happened hundreds of thousands if not million years ago and both fields have to cope with the lack of direct evidence (i.e., lack of direct fossil record on language or music). It is clear that because of the scarcity of relevant information there is no agreement how to evaluate these proposals. One group (Mehr et al.) argues in favour of music as a credible signal of cooperative intent, whereas the other group (Savage et al.) argues in favour of music as a general bonding device replacing “ancient,” presumably less efficient bonding mechanisms (such as physical grooming). Both proposals have its merit as both groups suggest a function that can be efficiently performed by music. Yet, this is a weakness of these proposals as well. Deacon (Reference Deacon1993) criticized such an approach in his response to Dunbar's (Reference Dunbar1993) original idea: “Language makes X more efficient, therefor selection for X explains the origin of language” (Deacon, Reference Deacon1993, p. 699). The problem is that both music and language are very good at making many aspects of our life more efficient, therefore this cannot be the sole criteria.
How to move forward? One way to cope with this problem is to set up a list of criteria that potential solutions have to fulfil. Such a list was proposed for human language: honesty, groundedness, power of generalization, and uniqueness (Számadó & Szathmáry, Reference Számadó and Szathmáry2006). Similar lists were proposed later on (Bickerton, Reference Bickerton2009; Hurford, Reference Hurford2011). Although I am not claiming that it solved the problem of language evolution, yet it could bring us closer to the solution by making it clear what needs to be solved in the first place. Another way is formal modelling of evolutionary trajectories (e.g., Zachar, Szilágyi, Számadó, & Szathmáry, Reference Zachar, Szilágyi, Számadó and Szathmáry2018 on the origin of mitochondria). Although it is admittedly difficult, and especially so in a situation in the lack of direct evidence, formal models can help us by formalizing the assumptions behind different narratives.
Is this a coincidence that in a lineage where human language evolved music evolved as well? I do not think so. Unfortunately, the groups offer very little discussion on the relation of language and music. Although the second group observes similarities in the proximate level they seem to argue that the two have different functions: “However, the fact that music and language are both found universally in all known societies […] suggests that both music and language independently fulfill more fundamental adaptive functions […].”
I think that the observation made by the second group is open to a different interpretation. Namely, I would like to suggest that language and music share the same roots, they evolved from a shared ancestral communication system, which was neither language nor music in its modern form, just as the shared ancestor of humans and chimps were neither human nor chimp. I propose, following Számadó (Reference Számadó2010), that this shared ancestral system was a pre-hunt communication (charade) that served to organize and coordinate hunting effort in early hominins.
Note that this proposal is different from the “what language/music is good for” type of proposals because in our current societies charade is not really good for anything. We play it for fun, it is not a death or life issue. We do not play charade to coordinate anything or to signal coalition strength or to create everlasting bonds. Although the bonding function could be debated, as charade is a favourite party game, but realistically any other collective game could fill the same function. Therefore, it is difficult to think that there would be anything special in charade and that there were times when we played it for real. However, I would like to suggest that not just that we played it for real, but at that time it was everything we had (see Számadó, Reference Számadó2010 for details).
All in all, I would like to urge scientists working on the problem of language and music evolution to join their efforts to identify the ancestral communication system to language and music. It may not be the charade as I described it; however, it is very unlikely that these communication systems evolved independently from each other. Accordingly, the isolated study of both systems may not be as fruitful as the joint study of the two systems.
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In a twin submission, Mehr, Krasnow, Bryant, and Hagen and Savage et al. offer two interesting yet very distinct accounts for the evolution of human music and musicality. Before we dive into the evaluation of these different proposals, it is worth to clarify what is music, that is, what needs to be explained. Human music is a unique communication system unmatched in nature. We can communicate the whole range of human emotions with music, we can signal our commitment, our attention, intentions, we can coordinate work with music. Music relates to animal “song” similar to human language relates to the “language of the bees.” Interestingly enough, the species that evolved this unique communication system also evolved another unique communication system: human language.
It is hard not to notice the similarities between ideas proposed to explain the origin of human language on the one hand and music on the other hand. All the functions discussed by the two groups were proposed to explain the origin of language, as well. Famously, the “by product” theory was proposed by Chomsky and colleagues (Hauser, Chomsky, & Fitch, Reference Hauser, Chomsky and Fitch2002), perhaps even more famously the “vocal grooming” theory was originally proposed by Dunbar (Reference Dunbar1993) in the context of language evolution, the signalling of mate quality was proposed by Miller (Reference Miller2011), bonding of female coalitions was proposed by Knight (Reference Knight1998), and finally bonding between mother and her child was proposed by Falk (Reference Falk2004) as a selective force to explain the evolution of human language (see Számadó & Szathmáry, Reference Számadó and Szathmáry2006 for a review).
The similarities do not end here. Both fields aim to explain the origin of a unique communication system found only in humans, both fields aim to recreate a series of events that happened hundreds of thousands if not million years ago and both fields have to cope with the lack of direct evidence (i.e., lack of direct fossil record on language or music). It is clear that because of the scarcity of relevant information there is no agreement how to evaluate these proposals. One group (Mehr et al.) argues in favour of music as a credible signal of cooperative intent, whereas the other group (Savage et al.) argues in favour of music as a general bonding device replacing “ancient,” presumably less efficient bonding mechanisms (such as physical grooming). Both proposals have its merit as both groups suggest a function that can be efficiently performed by music. Yet, this is a weakness of these proposals as well. Deacon (Reference Deacon1993) criticized such an approach in his response to Dunbar's (Reference Dunbar1993) original idea: “Language makes X more efficient, therefor selection for X explains the origin of language” (Deacon, Reference Deacon1993, p. 699). The problem is that both music and language are very good at making many aspects of our life more efficient, therefore this cannot be the sole criteria.
How to move forward? One way to cope with this problem is to set up a list of criteria that potential solutions have to fulfil. Such a list was proposed for human language: honesty, groundedness, power of generalization, and uniqueness (Számadó & Szathmáry, Reference Számadó and Szathmáry2006). Similar lists were proposed later on (Bickerton, Reference Bickerton2009; Hurford, Reference Hurford2011). Although I am not claiming that it solved the problem of language evolution, yet it could bring us closer to the solution by making it clear what needs to be solved in the first place. Another way is formal modelling of evolutionary trajectories (e.g., Zachar, Szilágyi, Számadó, & Szathmáry, Reference Zachar, Szilágyi, Számadó and Szathmáry2018 on the origin of mitochondria). Although it is admittedly difficult, and especially so in a situation in the lack of direct evidence, formal models can help us by formalizing the assumptions behind different narratives.
Is this a coincidence that in a lineage where human language evolved music evolved as well? I do not think so. Unfortunately, the groups offer very little discussion on the relation of language and music. Although the second group observes similarities in the proximate level they seem to argue that the two have different functions: “However, the fact that music and language are both found universally in all known societies […] suggests that both music and language independently fulfill more fundamental adaptive functions […].”
I think that the observation made by the second group is open to a different interpretation. Namely, I would like to suggest that language and music share the same roots, they evolved from a shared ancestral communication system, which was neither language nor music in its modern form, just as the shared ancestor of humans and chimps were neither human nor chimp. I propose, following Számadó (Reference Számadó2010), that this shared ancestral system was a pre-hunt communication (charade) that served to organize and coordinate hunting effort in early hominins.
Note that this proposal is different from the “what language/music is good for” type of proposals because in our current societies charade is not really good for anything. We play it for fun, it is not a death or life issue. We do not play charade to coordinate anything or to signal coalition strength or to create everlasting bonds. Although the bonding function could be debated, as charade is a favourite party game, but realistically any other collective game could fill the same function. Therefore, it is difficult to think that there would be anything special in charade and that there were times when we played it for real. However, I would like to suggest that not just that we played it for real, but at that time it was everything we had (see Számadó, Reference Számadó2010 for details).
All in all, I would like to urge scientists working on the problem of language and music evolution to join their efforts to identify the ancestral communication system to language and music. It may not be the charade as I described it; however, it is very unlikely that these communication systems evolved independently from each other. Accordingly, the isolated study of both systems may not be as fruitful as the joint study of the two systems.
Financial support
S.S. gratefully acknowledge support from the Hungarian National Research, Development and Innovation Office NKFIH (grant number K 132250). S.S. was supported by the European Structural Investment Funds (ESIF) in Hungary (GINOP) 2.3.2-15-2016-00057.
Conflict of interest
None.