Climates during the Spread of Farming in the Mediterranean

Thomas Huet

University of Oxford

Niccolò Mazzucco

Università di Pisa

with the collaboration of Andrea Manica

University of Cambridge

Introduction

Late Foragers and Early Farmers

Late Mesolithic (LM)¹

Early Neolithic (EN)²

LM * Residenciality increase * Circular mobility to access discontinuous resources in time and space (seasonality) * Low demography EN * Permanent settlements * Logistic mobility to access localized resources for farming economy * High demography Cold weather favors a greater mobility. A la fin du Dryas III, vers 9,600 BC: amélioration du climat, et diminution des grands herbivores clairement documentée au Moyen-Orient et dans le Nouveau Monde, force les HG à intensifier leur foraging Climates: Near East is temperate and wet, North Africa transitioned to arid conditions, Southern Europe experienced is warmer and wetter Fertile Crescent | cultigens. , soil fertility for agriculture (cereals) and climates for livestock. Climates: broadly warm and stable The different periods defines characteristic anthropological moments. Conventional division in 3 phases, both for the Mesolithic and Neolithic. Standardized and heuristic way to represent the evolution of a culture. We represent here, using large brushes

Framework

Data: radiocarbon dates and palaeoclimatic data.

Neonet project

• Meso/Neo
• Dataset
• Online app
• Functions
• Openness

Early Mesolithic (EM)
Middle Mesolithic (MM)
Late Mesolithic (LM)
Early Neolithic (EN)
Middle Neolithic (MN)
Late Neolithic (LN)

Baume de Montclus, stacked SPD

Franchthi cave, stacked SPD

http://shinyserver.cfs.unipi.it:3838/C14dev/

source("R/neo_spd.R")
source("R/neo_spdplot.R")

neo_spd(df.c14 = df.c14)

• Open Data, Open Source, Open Access
• Scalable, Incrementable, Reusable, Analyzable

Materials and Methods

Data: radiocarbon dates and palaeoclimatic data.

Radiocarbon data

• Sources
• Alignment
• Outliers
• ROI
• Worflow

https://github.com/ropensci/c14bazAAR

https://github.com/zoometh/neonet

https://github.com/ahb108/rcarbon

ref_table_per.xlsx

EM - Early Mesolithic

MM - Middle Mesolithic

LM - Late Mesolithic

EN - Early Neolithic

MN - Middle Neolithic

LN - Late Neolithic

• 8 different databases and datasets. Among which 2 are the Neonet datasets. We collect using the c14bazAAR and curated with NeoNet functions.
• mapping table with period and culture coming from different datasest to be mapped to the Neonet main classes (10 classes, among which 4 are undefined and period transition).
• Using

c14_aberrant_dates.tsv

• With R functions coming from the C14bazaar R package and curated with the NeoNet R series of functions, we are gathering some 10,000 radiocarbon dates coming from 8 different datasets and databases.
• We map these dates to the Neonet periods (here on the left class).
• Then we remove duplicated dates and discard outliers (currently in process).
• Some 4,000 dates are now available for the study.

Climates data

• Sources
• Methods

Mean annual temperature (ºC)

Annual precipitation (mm year ^-1)

Biome (pollen-based)

Beyer et al. 2020³

https://github.com/EvolEcolGroup/pastclim

B <- MAP < 10 * Pthresh
BW <- B & MAP < 5 * Pthresh
BWh <- BW & MAT >= 18
BWk <- BW & MAT < 18
BS <- B & MAP >= 5 * Pthresh
BSh <- BS & MAT >= 18
BSk <- BS & MAT < 18

A <- Thot >= 18 & !B
Af <- A & Pdry >= 60
Am <- A & !Af & Pdry >= 100 - MAP / 25
Aw <- A & !Af & Pdry < 100 - MAP / 25

• pastclim R package to recreate the Koppen Climate classification (KCC) for past periods, currently from 8,000 BC to 5,000 cal BC (expressed here in cal BP)
• KCC based on average temperature and precipitation patterns, dividing them into five main types: tropical, dry, temperate, continental, and polar. Each type is further subdivided based on seasonal precipitation and temperature patterns (30 classes).
• The pastclim KCC current resolution is 30” = 0.5 degrees = c. 50 km. It uses the Beyer et al. 2020 dataset.

Modelling

• Dates medians and KCC extraction
• Dates interpolation

Most recent LM and most ancient EN date weighted medians by site

• For a given site, we select either the most recent LM date (ex: Monte Frignone) or simetrically the most ancient EN date (ex: Le Baratin)
• Extract on the radiocarbon date weighted median from the Summed probability density (SPD)

• With R functions coming from the C14bazaar R package and curated with the NeoNet R series of functions, we are gathering some 10,000 radiocarbon dates coming from 8 different datasets and databases.
• We map these dates to the Neonet periods (here on the left class).
• Then we remove duplicated dates and discard outliers (currently in process).
• Some 4,000 dates are now available for the study.

• For a given site, we select either the most recent LM date (ex: Monte Frignone) or simetrically the most ancient EN date (ex: Le Baratin)
• Extract on the radiocarbon date weighted median from the Summed probability density (SPD)

Spread of Neolithic in the Mediterranean

Radiocarbon dates are still being revised, and many of them need to be verified. First modeling

Eastern Mediterranean (in BC)

• 9000
• 8400
• 7600
• 6800
• 6200

Case study 1: Balkans

• Climates
• Sites
• Assumptions

• Rapid expansion in the Southern Balkans (Csa).
• Northern Balkans expansion required adapting agriculture and stockbreeding systems to colder climates (Dfa, Dfb)
• Slowdown of Neolithic expansion. Early northern occupations, such as Porodin (idf 26).
• Confirms: Krauß et al. 2018⁴, Ivanova et al. 2018⁵.

Central Mediterranean (in BC)

• 6000
• 5800
• 5600

Case study 2: Italy

• Climates
• Sites
• Assumptions

• 5800-5600 BC: Rapid inland expansion Csa, for ex: La Marmotta (idf 94) and Rio Tana (idf 149), Central Italy
• 5600 BC: Slowdown linked to the transition to a climate with no dry season (Cfa, Cfb), northern Abruzzo.
• Confirms: Binder et al. 2022⁶, Mazzucco et al. 2023⁷.

Western Mediterranean (in BC)

• 5600
• 5300

End of the Mediterranean Neolithisation

Climates evolution

• Late foragers: Drop of the inhabited cold climates from 11k BP to 7k BP. In 9k BP newly occupied occupied Cold, dry summer, cold summer, possibly corresponding to the higher mountain range (Atlas, Alps, Pyrenees, etc.)
• Early Farmers: 11k and 10k 2 main climates, continuous area: Fertile Crescent. Arid climates increases in 9k: arid margins (oasis). 8k and 7k: neolithisation of cold and temperated areas (Bulgaria, Southern Germany, etc.)
• Comparison: LM occupied a larger diversity of ecozones. EF replace HG in cold climate over 4,000 years
  

Discussion

Rproductible methods. Enhancement of cultural and climatic data

Climates occupied by the Early Farmers

Thank you

https://github.com/zoometh/neonet

• Contribution: mapping table (archaeologists), interpolation methods (mathematician), aggregating data from other sources (aDNA, etc.), etc.

Footnotes

1. Late Foragers. Create an image in a portrait layout of: A Mediterranean coastal area, view from distance (bird eye), during the Late Mesolithic, with a temperate to cold and humid climate, showing an estuary river banks and a part of a marsh. The dominant colors in the image should be cool tones, such as blues and green, and the people should be dressed in furs suitable for cold to temperate climates (Koppen climate classes: Cfb and Dfa). Include only 5 characters: A women collecting sea shells and collecting fruits and wild seeds in cane baskets. A children collecting wild seeds in cane baskets. A man fishing with a vegetal net. A woman hunting ducks with a bow. A man skinning a fish. Include only these items: A vegetal net An arrow. Living wild animals should be distant from humans. The characters and animals in the image must be realistic. The faces of the people should be well-defined. The tools should be made of wood, flints and bones only. The image should have: No domestic animals. No ceramic potteries. No glass. No candle or wood fire. Do not include anything that I didn’t described

2. Early Farmers. The scene depicts a Mediterranean landscape set in a river valley of the inland Iberian Peninsula during the Neolithic period. The environment reflects the typical Mediterranean vegetation, including holm oaks, oak trees, and shrubs. The landscape shows a mosaic of forests and small cereal fields, with more emphasis on the dense forest. In the foreground, a group of five people is working in the fields, harvesting wheat using wooden and flint sickles. The group consists of three men and two women, all dressed in prehistoric brown wool and linen garments, appropriate for the period. In the background, there is a small flock of black goats and brown sheep, which are being watched over by an elderly woman and a child, both holding wooden staffs. The animals are enclosed within a small wooden pen located far from the cereal fields prompt@ChatGPT.

3. Beyer, R. M., Krapp, M., & Manica, A. (2020). High-resolution terrestrial climate, bioclimate and vegetation for the last 120,000 years. Scientific data, 7(1), 236.

4. Krauß, R., Marinova, E., De Brue, H., & Weninger, B. (2018). The rapid spread of early farming from the Aegean into the Balkans via the Sub-Mediterranean-Aegean Vegetation Zone. Quaternary International, 496, 24-41. https://doi.org/10.1016/j.quaint.2017.01.019

5. Ivanova, M., De Cupere, B., Ethier, J., & Marinova, E. (2018). Pioneer farming in southeast Europe during the early sixth millennium BC: Climate-related adaptations in the exploitation of plants and animals. PLoS One, 13(5), e0197225. https://doi.org/10.1371/journal.pone.0197225

6. Didier Binder, Lucia Angeli, Louise Gomart, Thomas Huet, Roberto Maggi, Claire Manen, …, (2022). Le complexe de la Céramique Imprimée en Méditerranée centrale et nord-occidentale : une synthèse chronoculturelle (VIIe et VIe millénaires AEC). In: Céramiques imprimées de Méditerranée occidentale (VIe millénaire AEC) : données, approches et enjeux nouveaux. Actes de la séance de la Société préhistorique française de Nice (mars 2019), D. Binder and C. Manen (eds), Paris, Société préhistorique française.

7. Mazzucco, N., Mineo, M., Gibaja, J.F. (2023). La Marmotta site in the framework of the Early Mediterranean Neolithic. In: The Submerged Site of La Marmotta. Oxbow Books, Rome, Italy. Oxford.

8. Ammerman, A. J., & Cavalli-Sforza, L. L. (1971)[^2]. Measuring the rate of spread of early farming in Europe. Man, 674-688.

9. Fort, J. (2022). The spread of agriculture: quantitative laws in prehistory?. In Simulating Transitions to Agriculture in Prehistory (pp. 17-28). Cham: Springer International Publishing.

10. Betti, L., Beyer, R. M., Jones, E. R., Eriksson, A., Tassi, F., Siska, V., … & Manica, A. (2020). Climate shaped how Neolithic farmers and European hunter-gatherers interacted after a major slowdown from 6,100 BCE to 4,500 BCE. Nature Human Behaviour, 4(10), 1004-1010.

11. Binder, D., Angeli, L., Gomart, L., Huet, T., Maggi, R., Manen, C., … & Tagliacozzo, A. (2019, March). L’Impresso-cardial du nord-ouest et ses rapports avec la «zone-source»: une synthèse chrono-culturelle. In Céramiques imprimées de Méditerranée occidentale. Matières premières, productions, usages.