A potential new proxy for tracking livestock densities and associated anthropogenic activity

Lead Research Organisation: University of Sussex
Department Name: Sch of Global Studies

Abstract

When the Spanish conquistadors arrived in Peru in the 1530s, the highly advanced Inca state was the largest empire to have existed in the Americas, stretching from the present day Colombian border to central Chile. The Inca owed much of their spectacular success to the practices and infrastructure of earlier societies (which they had freely-adopted), as well as to their innovative adaptation strategies in the face of climatic change. However, the details surrounding the expansion, success and ultimate collapse of all these so-called pre-Columbian cultures are still poorly understood, in part because they failed to develop any form of written language and so left no documentary evidence behind. Questions relating to population size, trading activities, land use and large-scale demographic change are therefore difficult to resolve from archaeological evidence alone. This problem (by no means unique to South America) also highlights the difficulty faced by contemporary interdisciplinary climate research, which is becoming increasingly interested in how societies have responded and adapted to past climatic pressures so that models for predicting future responses under global warming scenarios might be tested.

One way of addressing this problem is provided by the reliance of these early Andean agro-pastoral societies on their livestock, which was crucially important both as a valuable food, wool, fuel and fertiliser resource, but also as a means of facilitating trade between the coast, highlands and rainforest. Being able to estimate the changing densities of livestock on the landscape could provide a first order assessment of land-use, trading strength and population migration through time (especially if considered alongside other palaeoenvironmental evidence). Promising new data from Marcacocha, a well-studied 4200-year lake record from highland Peru, has suggested a link between the quantities of camelid (chiefly llama) dung deposited in pasture areas on trading routes and the abundance of soil-dwelling mites preserved in the sediments of those grazing areas. Mites are micro-arthropods, familiar in domestic settings for inhabiting carpets and mattresses. However, some species live exclusively in moist grasslands, where they break down organic matter to provide a rich food source. Pasture mite abundances are known to respond directly to nutrient fluxes via livestock dung and their remains are often well preserved in lake sediments (as at Marcacocha).

This project proposes to apply rigorous scientific procedures to the promising Marcacocha material to test the hypothesis that mite remains can track livestock density changes through time. We have three lines of approach. The first is to use detailed taxonomy to properly identify the species present and, using what we know of their modern habitat requirements, to derive an environmental history of the sequence. Certain mite taxa may even provide evidence for particular animal groups, e.g. camelids and/or introduced livestock (e.g. cattle, sheep). The second approach is to compare the mite data against a more established proxy for detecting large animals, namely the spores of dung-inhabiting fungi (e.g. Sporormiella). Whilst spore preservation can be problematic in some settings, we know that they are present at Marcacocha. By 'calibrating' the mite data against that derived from spores (never before attempted), we will be able to develop an alternative and potentially more sensitive means of detecting herbivore presence in situations when Sporormiella evidence is lacking. Finally, we will compare the new mite (and spore) data against the other proxy evidence for anthropogenic change at Marcacocha to build up a much more detailed interpretation of the history of the region.

Development of this novel technique has applications not only across the Andes, but also in other pastoral settings (e.g. Greenland Norse) and in the study of more ancient megafaunal extinctions.

Planned Impact

The main beneficiaries of the proposed research beyond the academic realm (see separate statement) fall into two categories:

1. Young people and interested members of the public will benefit via an increased understanding of the scientific approaches taken to understanding past climates, the key questions that drive archaeological science, the unresolved questions around the socio-economic development of past cultures and their response to climatic forcing, and our current knowledge of natural climate variability. The engagement of the research team with undergraduate students as part of their normal duties will contribute to the basic training of the next generation of young scientists and policy makers in the UK.

2. Environmentally-based NGOs working in South America and concerned with biodiversity conservation and sustainable land-use management practices in the Andes (e.g. the Asociación Ecosistemas Andinos, ECOAN). Today's Andean communities continue to face significant environmental pressures brought on by global warming, including reduced fresh water availability and land degradation. Organisations such as ECOAN will benefit from high-resolution datasets that document land-use changes over time in response to climatic variability and will help to inform ongoing policy decisions in conjunction with modelled climate change scenarios.

Our engagement activities will draw on our connection with the Natural History Museum (NHM) that will enable us to reach a very diverse audience indeed. Nature Live events are popular interactive sessions with visitors to the Museum and, furthermore, are made available via their website for subsequent video streaming. The proposed project web-pages in English and Spanish (also hosted by the NHM) will communicate the findings of the project to a variety of potential users, both academic and non-specialist alike. Furthermore, our media engagement will publicise the project locally, nationally and internationally; previous experiece will allow us to target Latin American (i.e. Spanish language) outlets in particular. More local engagement (via pro-active talks for organisations such as the Geologists' and Geographical Associations) will help to inform and inspire young scientists.

The direct societal or economic impact of this research is difficult to quantify, but through the generation of high-quality new data sets that have implications for understanding human responses to climatic change, this research programme will ensure that the UK remains an important centre for tackling key earth system science questions.

Publications

10 25 50
 
Description This project aimed to test the novel hypothesis that mite remains in lake sediments could be used to track livestock density changes across a landscape through time. We have used the environmental history of a relatively well-studied, small lake site in Andean Peru (Marcacocha) as a framework within which to compare our new datasets. In this project, we have:

(1) Identified species of mites present in the lake and surrounding pasture and established their broad habitat requirements (constituting new records for Peru). This was achieved by a combination of fossil analysis and modern field ecology. This enabled us (in conjunction with existing datasets) to develop an environmental history of the lake basin over the last 1200 years. The specimens provided new distribution data for the taxa involved, while some may represent species new to science: this is currently being verified by the co-PI at the Natural History Museum (London), so that they can be formally described and photographed and the species names properly published.

(2) Generated a new dataset of coprophilous (dung-inhabiting) fungal spores over the same 1200-year interval as the mite record for comparative purposes. Our original hypothesis was that first order changes in these two records would closely track each other, since we postulated that the two proxies were controlled primarily by the same environmental driver (i.e. livestock density in the pasture). Our results suggest that the relationship between the proxies is actually more complex than originally surmised and that, whilst a viable environmental history can be derived, neither proxy can wholly be relied upon in isolation. In particular, the poorly dispersed fungal spores appear to be more common during dry intervals (when livestock are able to get closer to the lake centre); meanwhile, the fossil mite populations appear to track historical events more closely, such as the disappearance of llama herds following the collapse of the Inca empire. These outcomes have opened up important further research questions (currently being pursued) concerning the exact response of the different proxies in settings such as this and whether the physical processes by which spores and mite remains become incorporated into the lake sediments can explain the disparity in the records. Building on the results of this project, further work should enable a protocol to be established for the application of this technique in a variety of other historical, livestock-dependent agro-pastoral settings.
Exploitation Route Academic audience: The main academic outcomes from the project relate to: (a) implications concerning the critical use of different proxies to determine animal presence on the landscape; and (b) new taxonomic / ecological data. Three publications deriving from the project are currently in preparation; several talks have already been delivered to academic audiences. A meeting at the INQUA Congress in Japan in 2015 was especially relevant and likely to have had genuine cross-disciplinary, international 'reach'. A session was convened with the express purpose of exploring contentious issues around the use of the long-established 'default' proxy of coprophilous fungal spores; the outcomes of our project were featured heavily in this discussion. The intention is to facilitate a more in-depth, multi-disciplinary research project that builds on our results. A paper is about to be submitted.
Non-academic audience. Several outreach-style talks and media engagements have already been undertaken (more are currently planned). One noteworthy activity was the invitation to present our results in Peru as part of a symposium addressing future climate change and food security issues, with a view to assessing likely impacts, resilience and adaptation strategies. Organised by the French Embassy and the Institute of Research for Development, the audience included the Peruvian Minister for the Environment and the Deputy Minister for Agricultural Policy, as well as agricultural and environmental policy makers and a variety of environmental NGOs. Our work was used to provide a historical context for future climate change and socio-economic scenarios and will help to inform future policy decisions. Participation in this high-level forum has also enabled us to increase our engagement with governmental and non-governmental organisations in Peru concerned specifically with biodiversity conservation and sustainable land-use management practices.
Sectors Agriculture, Food and Drink,Environment,Culture, Heritage, Museums and Collections

 
Description As we set out in our original proposal, the direct societal or economic impact of this research can be difficult to quantify. However, the generation of high-quality new datasets detailing the nature of, and human response to, climatic change has implications for a range of contemporary actors and stake-holders concerned with the sustainability of Andean livelihoods today. Highland communities continue to face significant environmental pressures brought on by global warming, including reduced fresh water availability, food security issues and land degradation, all of which have historical precedent. Organisations concerned with land-use management practices and biodiversity conservation in South America (such as the Asociación Ecosistemas Andinos, ECOAN, with whom we have strong links) use our data to help inform their policies for the introduction of economically and environmentally sustainable land-use practices for rural indigenous Peruvian populations. These organisations also directly influence the development of governmental policy with regard to these issues. Indeed, as detailed in our key findings and outputs submission, our data has also been presented at the highest levels of government to provide climatic and historical context to help inform the development of national climate change resilience and food security policies.
First Year Of Impact 2013
Sector Agriculture, Food and Drink,Environment,Culture, Heritage, Museums and Collections
Impact Types Societal

 
Title National Geoscience Data Centre submission 
Description Deposition of data resulting from the project with the National Geoscience Data Centre, maintained by the British Geological Survey. Data pertain specifically to that presented in the Journal of Archaeological Science paper. Data are publicly available via http://dx.doi.org/10.5285/58d434f7-81ab-4086-b6f2-d90a775ff439 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? Yes  
Impact None to date. 
URL https://www.bgs.ac.uk/services/ngdc/citedData/catalogue/58d434f7-81ab-4086-b6f2-d90a775ff439.html
 
Description BBC 4 documentary interview 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact On-camera interview for a two-part documentary filmed by the BBC that was broadcast on BBC4 in early 2015 about the societal response of the Inca to climate change in the Peruvian Andes.

The documentary will have international reach. However, given that it has only recently been broadcast, any potential impact is currently speculative. The only immediate outcome so far is consultation for another BBC documentary programme that will feature Andean ecology and climate change.
Year(s) Of Engagement Activity 2015
URL http://www.bbc.co.uk/programmes/b04xdpjy
 
Description Chair conference session (Nagoya, Japan) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Study participants or study members
Results and Impact International INQUA conference (July/August 2015), Nagoya, Japan. Convening and chairing a session, leading the post presentation discussion forum. Audience of around 70 people, including academics and postgraduates.
Year(s) Of Engagement Activity 2015
 
Description Conference presentation (Lima) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact Invited symposium presentation at Cambio climático y seguridad alimentaria en el Perú: impacto, adaptación, resiliencia (Climate Change and Food Security in Peru: impacts, adaptation, resilience) organized by the French Embassy in Peru, the International Potato Center (CIP) and the Institute of Research for Development (IRD). The Peruvian Environment Minister, the Deputy Minister for Agricultural Policy and the French Ambassador were in attendance. Audience included agricultural and environmental policy makers and a variety of environmental NGOs. Presentation (Lecciones de la adaptación por los Incas al último calentamiento global de la edad media - Lessons of Incan adaptation to global warming in the Middle Ages) was put together by the PDRA on the grant and co-presented with a colleague (G Thiele).

Notable discussion from audience members; requests for further information. Influence on food security issues under conditions of changing climate difficult to ascertain at this stage, but collectively the meeting occurred at governmental level for the purposes of informing national climate change policy and participation in international fora.
Year(s) Of Engagement Activity 2014
URL http://www.ambafrance-pe.org/simposio-cientifico
 
Description Conference presentation (Nagoya, Japan) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Study participants or study members
Results and Impact International INQUA conference (July/August 2015), Nagoya, Japan. Oral presentation to around 70 people, including academics and postgraduates. Participation in subsequent lively Q&A round-table discussion.
Year(s) Of Engagement Activity 2015
 
Description Interview for BBC World Service 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact Interview with BBC World Service programme Newsday.
Year(s) Of Engagement Activity 2019
URL https://www.bbc.co.uk/programmes/p06y64ml
 
Description Interview with Agricultural Biodiversity weblog 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact Interview with professional Agricultural Biodiversity weblog about the recently published article in Journal of Archaeological Science.
Year(s) Of Engagement Activity 2019
URL https://agro.biodiver.se/2019/01/tracing-environmental-history-through-llama-poo-fungi-and-mites/
 
Description Interview with Atlas Obscura weblog 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact Interview with Atlas Obscura weblog resulting from publication of Journal of Archeological Science article.
Year(s) Of Engagement Activity 2019
URL https://www.atlasobscura.com/articles/llama-poop-eating-mites-in-the-andes
 
Description Invited lecture to overseas visiting undergraduate biology students, Herstmonceaux (Queens University, Canada) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Undergraduate students
Results and Impact Invited lecture to around 35 visiting overseas undergraduate biology students from Queens University, Canada. Detailed Q&A and discussion session followed, both in a group setting and with individuals.
Year(s) Of Engagement Activity 2017
 
Description Invited presentation (Beijing) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Study participants or study members
Results and Impact Invited presentation at the Institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing, China (August 2015). Data presented (of which this study's outcomes formed a significant part) followed by a discussion seminar for students (UG and postgraduate). Audience of about 40 individuals. Discussion of possible future collaborations have resulted from this visit.
Year(s) Of Engagement Activity 2015
 
Description Invited seminar, Quaternary Discussion Group, University of Cambridge 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact Invited presentation to introduce the project to a mixed (largely academic) audience of around 30 people. Open to the general public. Detailed discussion with attendees followed.
Year(s) Of Engagement Activity 2016
 
Description News article for the website of the journal Science 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact Interview with Science (turned into a news piece) about the recently published paper in Journal of Archaeological Science resulting from the project. The piece was picked up by other news outlets (e.g. the Smithsonian magazine (https://www.smithsonianmag.com/smart-news/what-llama-poop-eating-mites-tell-us-about-rise-and-fall-inca-empire-180971206/).
Year(s) Of Engagement Activity 2019
URL http://www.sciencemag.org/news/2019/01/mites-feed-llama-poop-may-track-rise-and-fall-incan-empire
 
Description Presentation (TMS meeting) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Type Of Presentation paper presentation
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Oral symposium presentation to the Ostracod Group of the Micropalaeontological Society. Annual weekend meeting, held at the University of Sussex, Brighton UK on 6 October 2012. Audience of around 10 people, including primarily postgraduates and undergraduates.

Plan for future activity (publication, collaboration) made as a direct result of this presentation.
Year(s) Of Engagement Activity 2012
 
Description Press release from the Natural History Museum, London 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact Press release by the Natural History Museum following the publication of an article in Journal of Archaeological Science. One of the co-authors is affiliated to the NHM. The article was picked up by other web-based news outlets.
Year(s) Of Engagement Activity 2019
URL http://www.nhm.ac.uk/discover/news/2019/january/the-rise-and-fall-of-the-inca-empire-is-recorded-in-...
 
Description Public lecture, Geol Soc (Farnham) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Public lecture given to members of the Farnham Geological Society (9th November 2012). Around 25-30 audience members.

Request for additional information / copies of publications.
Year(s) Of Engagement Activity 2012
 
Description Public lecture, Geol Soc (West Worthing) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Public lecture given to members of the West Worthing Geological Society (17th January 2014). Audience around 35-40 people.

Request for further information / publications.
Year(s) Of Engagement Activity 2014
 
Description Seminar presentation (QMUL) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Invited seminar at the Dept of Geography, Queen Mary, University of London. Academic audience (faculty, UG and PG students) of around 15 people.

Academic enquiries and requests for publications resulted from this talk.
Year(s) Of Engagement Activity 2014
 
Description Workshop presentation (Kiel) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Type Of Presentation keynote/invited speaker
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Invited oral presentation given at a workshop held in Kiel, Germany (15-18th April, 2013) as part of the EU-funded 'Human Development in Landscapes' project. The workshop title was 'Socio-environmental dynamics over the last 12,000 years: the creation of landscapes'. The presentation was given in session 12: 'Social and environmental change in pre-Hispanic Latin America'. The talk was delivered by the named PDRA on the research grant. Audience consisted of academics, postgraduate and undergraduate students, policy makers, NGO representatives and media representatives.

Request for further information / publications. Planning of further collaborative work.
Year(s) Of Engagement Activity 2013