Angourakis et al.
CAA, session 34
Kraków, 25 April 2019
https://andros-spica.github.io/CAA-Angourakis-et-al-2019/

“Don't put all your eggs in one basket”

modelling cropping strategies and climate change in the Indus Civilisation

Andreas Angourakis, Jennifer Bates, Jean-Phillipe Baudouin,
Alena Giesche, Joanna Walker, M. Cemre Ustunkaya, Nathan Wright,
Ravindra N. Singh and Cameron A. Petrie

available at https://andros-spica.github.io/CAA-Angourakis-et-al-2019/
https://andros-spica.github.io/CAA-Angourakis-et-al-2019/index.html?print-pdf (printable version)

Logos

1. 'Thou shalt be ... diverse'

Image source (CC0 Public Domain), via Maxpixel.net
urban-dictionary
Source: https://www.urbandictionary.com/

"Diversity favours adaptation"

  • As finance motto: minimising risk
  • Fisher's fundamental theorem of natural selection (as genetic variance)
  • Applied at multiple levels:
    • Ecosystem: populations are more diverse → ecosystem adapts easier/faster
    • Population: individuals/groups are more diverse → population adapts easier/faster
    • Group: individuals are more diverse → group adapts easier/faster
    • Individual: practices are more diverse → the individual adapts easier/faster
  • A principle, not necessarilly a fact

Fitness landscapes

  • Used in eco-evo theory
  • fitness x multiple dimensions
  • Metaphoric/operational applications
  • Caveats, e.g., Do populations move through low fitness "valleys"?
  • "Seascapes": dynamic fitness landscapes

Scales of diversity

Local/momentum:
'hill climbing'
→ fitness maximiser

Regional/period:
'boat stabilising'
→ risk minimiser

Integration of multiple instances creates an average fitness landscape that buffers the diversity of conditions

2. Diversity in food production

See page for author [Public domain], via Wikimedia Commons

Diversity in food production

  • factor of food security
  • Increasing demand versus sustainability
  • International trade versus food sovereignty
  • Commercial crops, genetic engineering, landraces
  • Climate change, plagues

Multi-cropping

What impact does it have for resilience?
  • Two forms (Andrews and Kassam 1976, cited in Petrie & Bates 2017):
    • Sequential cropping
    • Intercropping
  • 'Traditional' practices (e.g., permeaculture)
  • Undermined by commercial crops but not lost

3. Case study: The Indus Civilisation

  • One of the great ‘Old World’ Bronze Age civilisations
  • First cities in South Asia ('Mature Harappan', c.2500-1900 BC)
  • Five (or four) known major urban centres

summer rain, winter rain

Giesche et al. 2019, Clim. Past Giesche et al. 2019, Fig. 1 “Predictable unpredictability”
J.-P. Baudouin (in preparation)
winter-rain summer-rain

Climate change

  • Urban phase
    (MH, 4.5 and 4.3 ka)
    → stronger winter precipitation

  • End of urban phase
    (MH-LH, 4.1 ka)
    → decrease in both the summer and winter precipitation

Food production

  • Main crops:
    • barley/wheat (winter)
    • millet/rice (summer)
  • Pulses
  • Other

Bates, Petrie & Singh 2018, Archaeol Anthropol Sci Bates, Petrie & Singh 2018, Fig. 8

Food production

  • Animal husbandry:
    zebu, water buffalo, sheep, goat, pigs (?)

  • Fishing, hunting

  • Role of herding?

4. Modelling cropping strategies

Goal

to explore human adaptation to the diverse landscapes of NW India and expose the sustainability of different types of food production regimes, mainly in terms of cropping strategies, in front of abrupt climate change

Rationale

  • rural settlement(s)
  • local scale
  • food production/consumption
  • Explore parameters/scenarios
  • Questions:
    • Does diversity favours adaptation?
    • Is it detrimental to generating surplus?
Goal model

Elements

  • Household: propinquity and co-residence, rather than kinship
  • Group: set of households, united by kinship or coexistence; may form a 'settlement'
  • Patches: 1 hectare, vary in soil, water balance, and land use
units infograph

Model design, insofar

Household economy

Household demography

Structure

Household structure

Household demography

Dynamics

  • Age/sex-specific submodels: mortality (Coale-Demeny, from demogR package), nuptiality and fertility (Peristeva & Kostaki 2007, 2015)
  • Open population
  • Couples: residence rule and kinship tabu
  • Sensitivity to population size
  • Local instabiliy, stability, and exponential growth

Household economy

From land use to diet

  • Food production at household-level
  • Diet and nutrition
  • Specific strategies applied to patches with specific (changing) conditions
  • Sharing/exchange to be realised at group-level

Household economy

Structure

multi-level conection between land use and diet

Household economy

Dynamics

economic cycle

Data input

Soils and crop conditions

FAO-soil-portal
Challenge: model animal husbandry

Foodstuff nutrition values

Challenge: raw or cooked?
Bates, Petrie & Singh 2018, Fig. 8

Conclusions I

  • The effects of diversity in food production can vary with the time and spatial scale
  • Case studies in archaeology can offer insight on the 'long durée'...
  • But modelling (particularly, ABM) can connect small/short with large/long scales

Conclusions II

  • Connections made with ABM can be built on meaningful mechanisms
  • Accounting for:
    • Variability of environmental conditions
    • Social dynamics of various complexity
    • Sets of assumptions that can be flexible and testable (alternative designs, scenarios)
  • Challenge: still lack a shared, coherent, reproducible framework for modelling food production across cultures and for many generations

'TwoRains' project

ERC, 2015-2020



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Acknowledgements

Thanks to the Land, Water and Settlement and TwoRains teams:

Aftab Alam, Alessandro Ceccarelli, Sagorika Chakraborty, Sudarshan Chakradhari, Arti Chowdhary, Yama Dixit, Charly French, Adam Green, Henry Green, Lily Green, David Hodell, Penny Jones, Carla Lancelotti, Emma Lightfoot, Frank Lynam, Sayantani Neogi, Hector Orengo, Arun Kumar Pandey, Danika Parikh, Vikas Pawar, Amit Ranjan, David Redhouse, Dheerendra Pratab Singh, & Akshyeta Suryanarayan.

Special thanks also to the Department of AIHC and Archaeology, BHU, the European Research Council (ERC), and the UK-India Education and Research Initiative (UKIERI) for support and funding, and to the Archaeological Survey of India for permission to carry out the work.

“Don't put all your eggs in one basket”

modelling cropping strategies and climate change in the Indus Civilisation

Andreas Angourakis, Jennifer Bates, Jean-Phillipe Baudouin,
Alena Giesche, Joanna Walker, M. Cemre Ustunkaya, Nathan Wright,
Ravindra N. Singh and Cameron A. Petrie

THANK YOU!

available at https://andros-spica.github.io/CAA-Angourakis-et-al-2019/
https://andros-spica.github.io/CAA-Angourakis-et-al-2019/index.html?print-pdf (printable version)

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