Open Research Europe presents an interview with Elisa Bandini and Alba Motes-Rodrigo, two of the co-authors of ‘Naïve, unenculturated chimpanzees fail to make and use flaked stone tools’ in this month’s Research Spotlight.
This article was nominated by Dr Claudio Ottoni, a Guest Advisor for the Evolutionary Biology Collection:
“I found the subject of the study particularly interesting because it explores one of the features that make us human – toolmaking. I appreciated the novelty in their strategy, which was specifically aimed at testing the spontaneous or naturally developing abilities of toolmaking (and use) in apes. The conclusions appear to be relevant regarding the novel conditions tested (unenculturated chimps) and the number of individuals analysed, representing a significant advance in these kinds of studies that are so far very limited.
Dr Claudio Ottoni
How would you summarize your Research Article?
Despite substantial research on the emergence of the first sharp stone tools (i.e., flakes) in the archaeological record, how early hominins – ancestors of modern humans and members of the Hominini taxonomic group, including Homo erectus, Homo habilis, and H neaderthalensis – developed the abilities to make and use flakes is still debated. To explore this open question, we used chimpanzees (Pan troglodytes) as living models to reconstruct how early hominins may have learnt stone toolmaking and using abilities.
We provided naïve chimpanzees (N = 11) living in two research centers (Kristiansand Zoo, Norway and Chimfunshi Wildlife Sanctuary, Zambia) with a baited puzzle box that could only be opened using a sharp tool, and the materials to make the required flakes (e.g., hammerstones and cores).
Individuals are considered naïve in a specific task if they haven’t had previous experience with that task or with the materials involved in the task before the experiment takes place. So, in our case, the chimpanzees were naïve because they had never been tested in stone-tool making experiments.
Given our focus on the chimpanzees’ spontaneous flaking abilities, we did not show them how to make or use these tools, and instead carried out a baseline condition. As the chimpanzees did not develop the behavior, even after extended exposure to the materials, we decided to give them pre-made flakes to see whether they would use these tools instead. Despite plenty of time and exposure to the task, none of the chimpanzees in our study made or used flakes.
Our findings are consistent with the hypothesis that flake making and use might have evolved in the hominin lineage after the split between Homo and Pan seven million years ago, a scenario further supported by the initial lack of flaked stone tools in the archaeological record after this split.
What inspired you to investigate this?
We were inspired to run this study in light of the debate about the conditions and necessary cognitive abilities associated with the flaking abilities in early hominins, and the possibility that this behavior was uniquely human.
Previous ape studies on this topic only tested bonobos and orangutans that had been given training and/or demonstrations on the behavior, therefore there was an important gap in the literature on the spontaneous abilities of our closest living relatives, chimpanzees, to learn how to make and use flakes.
What were the outcomes of your research?
Our findings suggest that the ability to make and use flakes is not easily learned by chimpanzees without human demonstrations and previous experience with the task. Therefore, it is possible that human interaction of various types is required for chimpanzees to develop these abilities (e.g., through training and demonstrations).
In addition, the possibility remains that flaking abilities only emerged in the human lineage after our split from the ape LCA (the last common ancestor between hominins and apes approximately six to seven million years ago) and are beyond the learning abilities of apes.
Why is open research important to you and your co-authors?
Our team has always been very passionate about running experiments that are freely accessible and reproducible to other interested scientists across fields. No single study will provide definitive answers to any scientific question. So, by making our data available and open, we hope that other researchers will extend our studies to ensure that we are adopting the fullest approach towards answering our shared research questions.
What motivated you to publish with Open Research Europe?
We were drawn to Open Research Europe due to its straightforward submission format, the fact that it was completely open access, and that the peer review process was transparent and public.
All the reviewers and their comments are published alongside the article, as well as the different versions of the manuscript. This meant that our manuscript was immediately made available online, without having to wait for the lengthy peer review process often associated with the traditional publishing model. Also, the open format of the peer review means that it attracts reviewers who are professional and constructive in their comments.
What are your next steps?
We have now extended the project to test other species of primates, such as orangutans, and humans. We are also working on publishing our findings on two follow-up studies with chimpanzees, assessing their abilities to socially learn how to make and use flakes after human demonstrations have been provided (Bandini & Tennie, in review; Motes-Rodrigo & Tennie, 2022).
Read the full Research Article on Open Research Europe to learn more about the study and findings.
