This week, my guest feature is Dr Enrico Crema, a computational evolutionary archaeologist from the University of Cambridge! Enrico’s research covers a number of topics within archaeology, such as cultural evolution, Japanese prehistory and prehistoric demography. At the Department of Archaeology at Cambridge, he teaches the computational analyses of long-term human cultural and biological dynamics, and I took his ‘From Data to Interpretation’ statistics class during my MPhil last year! He has also developed a number of R packages, such as the rcarbon package which enables the calibration and analysis of radiocarbon dates for archaeological research.
What are your research interests and your particular area of expertise?
My (current) research themes are the study of cultural change as the result of an evolutionary process, its interplay with demography, and the application and the development of computational and statistical methods in archaeology and evolutionary anthropology.
What originally drew you towards human evolution studies?
I was very interested in palaeontology as a kid (yes dinosaurs!) and it was a hard choice to decide between an undergraduate degree in biology or in history/archaeology. I eventually chose the latter and initially thought I‘ve completely shut down any possibility to study biological evolution. A few years later during my masters at UCL, I sat on a module in Evolutionary Archaeology taught by Ethan Cochrane and Stephen Shennan. The realisation that I can be an archaeologist, but at the same time have an evolutionary perspective to study human behaviour and cultural change blew my mind, so during the first year of my PhD I sneaked into as many undergraduate and graduate courses in biology and biological anthropology to catch up.
What was your PhD topic? How did you choose this and who was your supervisor?
My PhD (at UCL Institute of Archaeology) looked into settlement dynamics among the Jomon hunter-gatherers in Japan. I was particularly interested in long-term fluctuations between nucleated and dispersed settlement patterns (after I spent a year in Japan as an exchange student during my undergraduate degree), so I developed a simulation model of group fission-fusion dynamics (extending some earlier ideas from human behavioural ecology), and came up with some new way of analysing settlement data, inspired by how chronological uncertainty is handled in crime science! I was very lucky to be supervised jointly by Andrew Bevan and Mark Lake on this – both were terrific mentors, and they profoundly shaped the way I approach research and teaching. I was also one of the last students joining the AHRC Centre for the Evolution of Cultural Diversity; there I met other students and post-docs that are now at the forefront of Cultural Evolutionary Studies around the world.
After your PhD, what positions have you held and where?
I was hired as a post-doc for Stephen Shennan’s EUROEVOL Project right after my viva (I did a Skype interview in the middle of the night while visiting the States for a talk). This was a great opportunity for me to dive into evolutionary archaeology with the support of an amazing team of colleagues. I particularly enjoyed weekly meetings with Stephen where he would suggest some obscure (to me) paper from another field, chatting about how some concepts can be adapted to study of cultural change. I then did an MSCA-IF at the Pompeu Fabra University in Spain with the CaSES research group led by Marco Madella (another great mentor!) and was involved in his ‘Simulpast’, a large collaborative project which focused on the theory and method of simulation studies in archaeology. I then came to Cambridge as a McDonald Fellow in 2016; I was supposed to work on a project on the emergence and evolution of cultural boundaries, but a few months later I accepted a lectureship that I am currently holding.
What current projects are you working on at the University of Cambridge?
I’m currently working on two projects. The first one is the Leverhulme-funded ‘Crops, pollinators and people: the long-term dynamics of a critical symbiosis (Buckbee)‘ project led by Prof. Martin Jones, with the collaboration with Prof. Richard Evershed (University of Bristol). We are looking at the origin and spread of insect-pollinated crops (buckwheat) using different approaches (e.g. DNA, organic residue analyses, etc.). I am working with my PhD Student, Marta Krzyzanska, who is doing some cool Bayesian analyses to model the ecological niches of Buckwheat.
The second project is an ERC-starter grant I’m directing called ‘Demography, Cultural change, and the Diffusion of Rice and Millet during the Jomon-Yayoi transition in prehistoric Japan (ENCOUNTER) ‘The project looks at the demic and cultural diffusion event that started about 3,000 years ago in the Japanese archipelago and brought a package of cultural and economic practices from mainland Asia. We are particularly focusing on how and why different regions reacted to this event, as we have evidence suggesting that some accepted the new practices immediately, while others resisted for several centuries, chose only specific cultural traits, or even reverted to previous practices after an initial uptake. We are also developing a series of bespoke methods for this project, and some are already giving us some new insights on prehistoric Japan. We just published a paper where we introduced a new approach for reconstructing prehistoric population dynamics and applied this to a case study from the Jomon period. The results showed that the timing of a major demographic event was 500 years earlier than we previously thought, questioning some of the climate-led hypothesis that suggested so far.
Why is your research important for understanding prehistoric human behaviour?
I think cultural evolutionary theory has still lots to offer in archaeological research. Many of the early works have focused macroevolution and there have been some attempts also to look at high-quality data from a microevolutionary perspective, reconstruing for example modes of transmission from frequency data (something I worked on a few years ago). But I think there has been less work between these two levels – in particular the study of horizontal transmission between populations. This is a tricky scale, but an exciting one that can help linking micro to macroevolution, and I hope the ENCOUNTER project can give us some new insights.
What project or publication are you most proud of?
That’s a tough question! I usually feel everything is a work in progress and start to see more and more flaws after papers get published! There is one paper I particularly enjoyed writing that was published few years ago on Human Biology though; it has an awful title (‘Cultural Incubators and Spread of Innovation’), but Mark Lake and I found some interesting dynamics on how adding uncertainty in payoff-biased transmission can be detrimental in larger interconnected groups.
What advice would you give to a student interested in your field of research?
When I was at high school, I hated math and computer science – now I teach both regularly, and enjoy coding. I think many fields are rapidly changing in this regard, and computing, quantitative skills, and open science are now becoming the norm. Ben Marwick wrote a great paper a few years ago where he argues for a shift from T-shaped researchers with an in-depth in knowledge in a particular domain to Pi-shaped researchers with in-depth knowledge in a particular domain and an in-depth knowledge in computing skills (see image below). So my advice is to be patient and learn those skills. Math and coding are like languages – you cannot enjoy learning one by just reading a book of grammar rules. But if you find the right content (mine was learning about spatial archaeology and cultural evolutionary theory) these skills will not be just useful but also enjoyable.