# Kava consumption and the rise of sociopolitical complexity in Oceania

## TL;DR

This study examines whether kava consumption helped build complex societies in Oceania but finds no strong evidence for a direct link.

## Contribution

The paper tests the 'drunk hypothesis' using kava and sociopolitical complexity in Oceanic societies.

## Key findings

- A positive but uncertain correlation was found between kava drinking and sociopolitical complexity.
- No evidence of coevolution between kava use and political or social traits was found after controlling for nonindependence.
- Ethnographic data suggest kava helped maintain, but not initiate, complex societies.

## Abstract

People’s attitude toward psychoactive substances is highly ambivalent, with an ongoing debate about their possible adaptive or maladaptive role in human evolution. Here, we present a cross-cultural study testing the hypothesis that consumption of the mind-altering beverage kava facilitated the emergence of complex, hierarchical societies in Oceania. Despite finding a positive, albeit uncertain, correlation between kava drinking and sociopolitical complexity, we found no evidence for the coevolution of these cultural traits. The results suggest that kava was not the primary factor explaining the rise of sociopolitical complexity in this region. However, ethnographic evidence shows that kava played a significant role in maintaining and strengthening existing political and social relationships.

Humans have been using psychoactive substances for millennia, despite their potential negative health and social consequences. According to some scholars, our craving for mind-altering drugs is an evolutionary mistake—a hijacking of our reward system. In contrast, the “drunk hypothesis” argues that intoxication has been adaptive and essential for the rise of large-scale societies because it promotes social bonding, increases cooperation, alleviates stress, and enhances human creativity. Here, we test this hypothesis using the example of kava, a traditional Pacific beverage with a range of psychoactive effects, made from the root of Piper methysticum. Our analysis of 83 Oceanic-speaking societies shows a positive relationship between traditional kava consumption and both political complexity and social stratification. However, the results are not robust to controls for nonindependence. Moreover, we found no evidence of coevolution between kava drinking and either of the two sociopolitical traits after controlling for spatial nonindependence. Despite the cultural significance of kava in many Pacific societies, our results suggest that its consumption was unlikely to have been a major driver of sociopolitical complexity, underscoring the importance of controlling for nonindependence in cross-cultural studies.