A young researcher has combined cutting-edge data analysis and ancient artefacts to gain fresh insights into our country's pre-European history.
The igneous rock obsidian has long been a useful reference for archaeologists to piece together the past, given Maori used it for a range of tools and activities.
University of Auckland researcher Caleb Gemmell took a new approach to studying them with what's called social network analysis - a set of tools and data models used to redefine the structure of social groups.
Building off a larger study supported by the Marsden Fund and research supervisors Dion O'Neale and Thegn Ladefoged, his Science Scholars project sought to investigate how pre-European Maori interacted and travelled throughout New Zealand.
"By using social network analysis, we modelled the flow of material throughout regions of the North Island."
This offered Gemmell an idea about how groups were trading the obsidian and travelling to sources of it, and yielded new information about the structure of the pre-European Maori societal groups and how they interacted.
"My work was programming based, and the data was the result of others' field and laboratory work that had originally been published in journals."
The obsidian artefacts had been obtained from archaeological excavations at specific sites, and then sourced using chemical analysis to determine where the material came from.
"I had access to a dataset of existing archaeological information and from there had to sort and organise the data and conduct social network analysis.
"I extracted further information from the network using programming tools in the hope of discovering new traits or patterns that were not found in the original data."
But the study wasn't simply a straightforward case of number-crunching.
"The nature of the research was 'exploratory', in that I had all this information but not necessarily a clear intention of what I was trying to find.
"This meant that a few of my methods led to dead ends and I had to go back to the drawing board to think of different approaches of analysing the data that could reveal something new, which was a constant challenge.
"There isn't exactly a single solution to overcoming this issue, but eventually we would find approaches that started to give us results and which we could improve upon."
Eventually, the data showed him how distinct communities were using distinct regions of obsidian sources.
"There was some interesting patterning in that the archaeological sites in West Auckland were very different from the archaeological sites in East Auckland and the Coromandel, even though both regions were geographically close.
"This suggests that simple economic explanations for obtaining obsidian based on the distance of an archaeological site to an obsidian source were not valid, and more interesting social factors were coming into play."
Gemmell believed the work would not only shed more light on pre-European Maori history, but also help establish the validity of using social network analysis in New Zealand archaeology.
"This work can be seen as a proof of concept, paving the way for more work to be done by the Marsden funded project in the future," he said.
"Thus hopefully more data can be collected and added to the dataset, growing the social network, allowing for more discoveries to be found."