In these ancestral environments, laughter-like sounds served a crucial role in social bonding, helping to build trust and establish hierarchies within groups. These vocalizations signaled that play was non-threatening, a vital communication tool in complex social structures. While not as cognitively or emotionally nuanced as human laughter, this form of communication laid the groundwork for the evolution of more complex vocal expressions in the human lineage.
References
Davila Ross, M., Owren, M. J., & Zimmermann, E. (2009). Reconstructing the evolution of laughter in great apes and humans. Current Biology, 19(13), 1106-1111.
This study investigates the acoustic characteristics of laughter in great apes and humans, suggesting that laughter-like vocalizations likely originated in a common ancestor of modern great apes and humans around 10 to 16 million years ago. The research supports the idea that these vocalizations were used in social contexts, particularly during play.
Panksepp, J., & Burgdorf, J. (2003). “Laughing” rats and the evolutionary antecedents of human joy? Physiology & Behavior, 79(3), 533-547.
Although this paper focuses on laughter-like behavior in rats, it draws parallels to the evolutionary origins of laughter in primates. The authors suggest that the roots of laughter can be traced back to early primates, possibly emerging as a social play behavior between 10 and 20 million years ago.
Preuschoft, S., & Van Hooff, J. A. R. A. M. (1997). The social function of “smile” and “laughter”: Variations across primate species and societies. In Nonverbal Communication: Where Nature Meets Culture (pp. 171-189). Lawrence Erlbaum Associates.
This chapter discusses the social functions of smile and laughter-like expressions in primates, tracing their evolutionary origins. The authors suggest that these behaviors likely emerged in a common ancestor of today’s great apes and lesser apes, around 10 to 15 million years ago, as part of social communication during play.
De Waal, F. B. M. (1996). Good Natured: The Origins of Right and Wrong in Humans and Other Animals. Harvard University Press.
In this book, Frans de Waal discusses the evolutionary basis for moral and social behaviors in primates, including laughter-like vocalizations. De Waal posits that these behaviors likely evolved during the middle Miocene, around 10 to 15 million years ago, as primates developed more complex social structures and communication methods.
King, B. J., & Shanker, S. G. (2003). The emergence of self: A comparative approach. In The Self in Context: A Tribute to Larry P. Nucci (pp. 19-40). Psychology Press.
This work explores the emergence of self-awareness and related social behaviors in primates, including laughter-like vocalizations. The authors suggest that these behaviors emerged around 10 to 15 million years ago, coinciding with the evolution of greater social complexity in primate groups.
