A Mini Meta-Analysis Infers that the Proportion of Bats in the Lapita Diet was Greater in Vanuatu than Elsewhere in the Pacific

Loren Howell

This study aimed to test previous observations from reviewed literature that human predation on bats played a significant role in the colonisation of the Asia-Pacific islands. This was done by estimating the proportion of bats in the terrestrial diet of Lapita People during colonisation of Remote Oceania. Cross-site comparisons of archaeological assemblages are statistically challenging, though necessary to draw reliable inferences from the data with any precision. A meta-analysis was performed to evaluate zooarchaeological datasets from 16 sites throughout the Lapita geo-temporal range that reported NISP. Statistical analysis was performed using Jamovi 2.6.44, and the proportion of bats in Lapita middens was estimated with 95% confidence. Results from a regional moderator analysis indicated that bats only comprised a small proportion (<20%) of the Lapita terrestrial diet across the broader Pacific, with a 6% difference in effect sizes between Near and Remote Oceania. However, an island group moderator demonstrated that in Vanuatu bats were consumed to a moderate extent, comprising approximately 40% of the terrestrial diet, which was higher than in the Bismarcks or Fiji by 23-32%, respectively. These findings reject previous assertions that bats played a significant dietary role in the colonisation of the Pacific, although infer that bat predation may have contributed to success of early settlements in Vanuatu with grounds for further investigations into how the Lapita mixed-based economy was adapted to local ecologies.