PEOPLE 3000 - PalEOclimate and the PeopLing of the Earth

Some of the most pressing policy issues facing nations today include the increasing intensity and frequency of extreme climate events (e.g. hurricanes, floods, and heat waves). All of these issues result from longer-term changes in disturbance regimes. Disturbance regimes refer to periodic challenges faced by a system. 

One of the only sources of data on what makes some systems more resilient and adaptable to such changes in disturbance regimes comes from integrated archaeological and paleoecological records. PEOPLE 3000 aims to integrate paleo-population, paleo-ecological, and paleo-social records to investigate the co-evolutionary properties of socio-environmental systems (SES) that enhance or diminish resilience to disturbance regimes. We ask: What makes some SES more resilient to changes in disturbance regimes than others?

Our project pushes the boundaries of SES research by linking together the processes of ecological and cultural inheritance, drawn from niche construction theory, and robust control theory to study the resilience of past SES to changes in the operation of disturbance regimes. We propose that human niche construction encodes memories or ways of adapting to a given disturbance regime (e.g., variability in a climate system) into cultural and ecological structures. Decision makers inherit cultural rules, norms, and ecosystems tuned to a previous set of disturbances that can make an SES vulnerable to unknown disturbances outside the purview of the system’s memory.

Our working group draws upon the expertise of archaeologists, paleo-ecologists, and computational modelers to test the proposition that the cultural and ecological inheritance of flexible systems improve the general resilience of SESs to changes in disturbance regimes relative to systems that inherit more productive, but also more rigid, cultural and ecological environments. We integrate paleo-population, paleo-institution, paleo-climate, and paleo-environmental data to develop an empirical typology of coevolutionary trajectories that SES might follow. 

Planned timeline

Phase two of People 3000 will integrate archaeological radiocarbon and paleoecological data, as well as information on social institutions, to develop coevolutionary models that correlate carrying capacity, social integration, and paleoclimate/ecological records.  This work, beginning in 2021 with our concurrent in-country meetings over Zoom, will enable the expansion of current datasets and the development of innovative new methods to assess the distinct developmental trajectories of SES in response to paleo-ecological stress. We anticipate completing this second phase in 2024. Specifically, we will follow the following time-line.

November 2021: Final workshop of Phase 1. This workshop will transition from Phase 1 to Phase 2 of the project. We will: (1) Continue synthesizing the paleoecological and climatological data sets from our 17 core case studies. (2) Evaluate the quality of these data across cases. (3) Work on the R code for integrating these datasets, using the HOPE and CLaSS data as test cases, with the PEOPLE 3000 archaeological radiocarbon dataset.

May 2022: Open online seminar for PEOPLE 3000 members and the PAGES community. This seminar will present major results from working group members and beyond. The seminar will disseminate our ongoing publications to the wider research community.

September 2022: First workshop of Phase 2. Anticipated goals: (1) Conduct wavelet and regime change analysis on paleo-ecological data of suitable quality from our 17 core case studies. (2) Identify case studies for expansion. (3) Finalize R code and publication integrating the HOPE global pollen and PEOPLE 3000 global radiocarbon data to assess associations between changes in human carrying capacity and vegetation change.

May 2023: Open online seminar for PEOPLE 3000 members and the PAGES community. This seminar will present major results from working group members and beyond. The seminar will disseminate our ongoing publications to the wider research community.

September 2023: Second workshop of Phase 2. Anticipated goals: (1) Construct time-series of the presence/absence of communal architecture and the frequency of violence in our core case studies. (2) Further develop methods to quantitatively analyze the association between changes in paleo-population proxies, paleo-ecological proxies and paleo-social proxies for integration during periods of change in climate disturbance regimes. (3) Develop open access R and Python code for cleaning and running analysis on our datasets.

May 2024: Open online seminar for PEOPLE 3000 members and the PAGES community to discuss approaches to synthesis and the development of phase three. We will focus on comparing models for the integration of data.

September 2024: Final workshop of Phase 2. Anticipated goals: (1) Comparison of case studies responses to changes in climate disturbance regimes. (2) Identify gaps in our database, methods and theory. (3) Apply for phase three of the working group.

In addition to the above workshops and online seminars, PEOPLE 3000 also holds a bi-monthly meeting on the first Friday of every other month. These meetings will continue so that the steering group can communicate with all members of the working group and accurately reflect the needs and goals of the group.

Learn more and participate

This group is open to anyone who is interested, and early-career researchers are encouraged to be involved:

- Sign up to the PEOPLE 3000 mailing list

- Follow the group on Twitter: https://twitter.com/PEOPLE_3000

- Contact the Steering Group

Know a case study that fits with this project? Get in touch! 

Read more about the group on its external website.

Background

PEOPLE 3000 is a global network of scientists committed to understanding what makes some human societies better at coping with changes in climate driven disturbance regimes than others. This work is important for understanding the properties of coevolving living networks of social and ecological agents that may be useful for coping with today’s rapid changes in disturbance regimes and associated extreme climate events.

In Phase 1, we focused on building a global data infrastructure for comparing basic patterns of human population ecology.

Phase 2 will continue the momentum gained during our first phase, with our ability to conduct globally comparative studies on the long-term coevolution of human populations, ecosystems, and social integration in the context of climate driven changes in disturbance regimes. In phase one of our working group, we developed a global dataset of archaeological radiocarbon dates useful for documenting changes in human population throughout the Holocene (Bird et al. 2021). As noted in our product list below, as part of the process of compiling this database, we published comparative studies of human population growth, decline, stability, and synchrony (e.g., Freeman et al. 2021; Bird et al. 2020; Freeman et al. 2020; Freeman et al. 2018b).

We also published methodological papers that lay a firmer foundation for using archaeological radiocarbon and alternative proxies for estimating changes in human paleo-population (e.g., Robinson et al. 2021; 1; Price et al. 2021;  Miranda and Freeman 2020). Finally, we published case studies that begin to document the coevolution of paleo-population, paleoecological systems, and social integration in the context of changing climate disturbances (e.g., Solheim 2021; Finley et al. 2020; Lima et al., 2020; Gil et al. 2020; Gayo et al., 2019). In addition to publications, our working group developed synergies evident in the submission of four research proposals over the last year (three under review and one funded).

Past timeline

Year 1: August 2017-July 2018
Year 2: August 2018-July 2019
Year 3: August 2019-July 2021