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Lithic landscapes: early human impact from stone tool production on the central Saharan environment.

Foley RA, Lahr MM - PLoS ONE (2015)

Bottom Line: The use of fire and over-exploitation of large mammals has also been recognized as having an effect on the world's ecology, going back perhaps 100,000 years or more.The Messak Settafet, a sandstone massif in the Central Sahara (Libya), is littered with Pleistocene stone tools on an unprecedented scale and is, in effect, a man-made landscape.The scale of debris also indicates the significance of stone as a critical resource for hominins and so provides insights into a novel evolutionary ecology.

View Article: PubMed Central - PubMed

Affiliation: Leverhulme Centre for Human Evolutionary Studies, Department of Archaeology and Anthropology, University of Cambridge, Cambridge, United Kingdom.

ABSTRACT
Humans have had a major impact on the environment. This has been particularly intense in the last millennium but has been noticeable since the development of food production and the associated higher population densities in the last 10,000 years. The use of fire and over-exploitation of large mammals has also been recognized as having an effect on the world's ecology, going back perhaps 100,000 years or more. Here we report on an earlier anthropogenic environmental change. The use of stone tools, which dates back over 2.5 million years, and the subsequent evolution of a technologically-dependent lineage required the exploitation of very large quantities of rock. However, measures of the impact of hominin stone exploitation are rare and inherently difficult. The Messak Settafet, a sandstone massif in the Central Sahara (Libya), is littered with Pleistocene stone tools on an unprecedented scale and is, in effect, a man-made landscape. Surveys showed that parts of the Messak Settafet have as much as 75 lithics per square metre and that this fractured debris is a dominant element of the environment. The type of stone tools--Acheulean and Middle Stone Age--indicates that extensive stone tool manufacture occurred over the last half million years or more. The lithic-strewn pavement created by this ancient stone tool manufacture possibly represents the earliest human environmental impact at a landscape scale and is an example of anthropogenic change. The nature of the lithics and inferred age may suggest that hominins other than modern humans were capable of unintentionally modifying their environment. The scale of debris also indicates the significance of stone as a critical resource for hominins and so provides insights into a novel evolutionary ecology.

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Frequency and distribution of lithics on the Messak as recorded in the OXY survey.a) Satellite image of the Messak, showing the seismic grid lines laid for the oil exploration. Each of these lines was walked by archaeologists from the Libyan Department of Antiquities, in both directions. Major archaeological localities were recorded on and between the lines, and the presence of lithics and rough density recorded in 2 x 2 m box every 100 m along the lines. b) Artefact density across the 2 x 2 boxes from the survey; white circles indicate presences of lithics, with the size reflecting low, medium and high density. c) Detail of a small 3 x 2 km area from within the survey area on the plateau’s surface, showing the presence and density of lithics. Sources: MESSAK SURVEY BACKGROUND MAP: satellite image donated by Occidental Plc. (WGS 1984 UTM Zone 33N, Extent: 2960788.37_291786.562_326263.362_2913482.77)
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pone.0116482.g003: Frequency and distribution of lithics on the Messak as recorded in the OXY survey.a) Satellite image of the Messak, showing the seismic grid lines laid for the oil exploration. Each of these lines was walked by archaeologists from the Libyan Department of Antiquities, in both directions. Major archaeological localities were recorded on and between the lines, and the presence of lithics and rough density recorded in 2 x 2 m box every 100 m along the lines. b) Artefact density across the 2 x 2 boxes from the survey; white circles indicate presences of lithics, with the size reflecting low, medium and high density. c) Detail of a small 3 x 2 km area from within the survey area on the plateau’s surface, showing the presence and density of lithics. Sources: MESSAK SURVEY BACKGROUND MAP: satellite image donated by Occidental Plc. (WGS 1984 UTM Zone 33N, Extent: 2960788.37_291786.562_326263.362_2913482.77)

Mentions: The very high density of stone tools can be measured at several levels (Fig. 3). Across the Messak as a whole, stone tools are extremely common, and any survey will encounter multiple scatters and isolated artefacts [50] [39–41,43,44,51], suggesting widespread use of the local sandstone as a source of raw material. At a more local level, stone tools are spread densely and extensively. In a very intensive survey carried out as part of a heritage assessment prior to oil exploration over >400 km2 in 2008 [52,53], 2 x 2 m plots were sampled every 100 m on transects running both east-west and north-south on ∼140 km2 of the Messak, with 300 m between transects (Fig. 3 and see Methods for details). The result was a lattice of plots every 100 x 100 m along the lines, with a density assessment at 8232 points, of which 6090 points were on the plateau surface of the Messak (i.e., excluding wadis). Of these 6090 sample points, lithics were identified in more than 60% including 17.6% with moderate to high density (Fig. 3). These data indicate a minimum density of quarter of a million lithics per km2.


Lithic landscapes: early human impact from stone tool production on the central Saharan environment.

Foley RA, Lahr MM - PLoS ONE (2015)

Frequency and distribution of lithics on the Messak as recorded in the OXY survey.a) Satellite image of the Messak, showing the seismic grid lines laid for the oil exploration. Each of these lines was walked by archaeologists from the Libyan Department of Antiquities, in both directions. Major archaeological localities were recorded on and between the lines, and the presence of lithics and rough density recorded in 2 x 2 m box every 100 m along the lines. b) Artefact density across the 2 x 2 boxes from the survey; white circles indicate presences of lithics, with the size reflecting low, medium and high density. c) Detail of a small 3 x 2 km area from within the survey area on the plateau’s surface, showing the presence and density of lithics. Sources: MESSAK SURVEY BACKGROUND MAP: satellite image donated by Occidental Plc. (WGS 1984 UTM Zone 33N, Extent: 2960788.37_291786.562_326263.362_2913482.77)
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4356577&req=5

pone.0116482.g003: Frequency and distribution of lithics on the Messak as recorded in the OXY survey.a) Satellite image of the Messak, showing the seismic grid lines laid for the oil exploration. Each of these lines was walked by archaeologists from the Libyan Department of Antiquities, in both directions. Major archaeological localities were recorded on and between the lines, and the presence of lithics and rough density recorded in 2 x 2 m box every 100 m along the lines. b) Artefact density across the 2 x 2 boxes from the survey; white circles indicate presences of lithics, with the size reflecting low, medium and high density. c) Detail of a small 3 x 2 km area from within the survey area on the plateau’s surface, showing the presence and density of lithics. Sources: MESSAK SURVEY BACKGROUND MAP: satellite image donated by Occidental Plc. (WGS 1984 UTM Zone 33N, Extent: 2960788.37_291786.562_326263.362_2913482.77)
Mentions: The very high density of stone tools can be measured at several levels (Fig. 3). Across the Messak as a whole, stone tools are extremely common, and any survey will encounter multiple scatters and isolated artefacts [50] [39–41,43,44,51], suggesting widespread use of the local sandstone as a source of raw material. At a more local level, stone tools are spread densely and extensively. In a very intensive survey carried out as part of a heritage assessment prior to oil exploration over >400 km2 in 2008 [52,53], 2 x 2 m plots were sampled every 100 m on transects running both east-west and north-south on ∼140 km2 of the Messak, with 300 m between transects (Fig. 3 and see Methods for details). The result was a lattice of plots every 100 x 100 m along the lines, with a density assessment at 8232 points, of which 6090 points were on the plateau surface of the Messak (i.e., excluding wadis). Of these 6090 sample points, lithics were identified in more than 60% including 17.6% with moderate to high density (Fig. 3). These data indicate a minimum density of quarter of a million lithics per km2.

Bottom Line: The use of fire and over-exploitation of large mammals has also been recognized as having an effect on the world's ecology, going back perhaps 100,000 years or more.The Messak Settafet, a sandstone massif in the Central Sahara (Libya), is littered with Pleistocene stone tools on an unprecedented scale and is, in effect, a man-made landscape.The scale of debris also indicates the significance of stone as a critical resource for hominins and so provides insights into a novel evolutionary ecology.

View Article: PubMed Central - PubMed

Affiliation: Leverhulme Centre for Human Evolutionary Studies, Department of Archaeology and Anthropology, University of Cambridge, Cambridge, United Kingdom.

ABSTRACT
Humans have had a major impact on the environment. This has been particularly intense in the last millennium but has been noticeable since the development of food production and the associated higher population densities in the last 10,000 years. The use of fire and over-exploitation of large mammals has also been recognized as having an effect on the world's ecology, going back perhaps 100,000 years or more. Here we report on an earlier anthropogenic environmental change. The use of stone tools, which dates back over 2.5 million years, and the subsequent evolution of a technologically-dependent lineage required the exploitation of very large quantities of rock. However, measures of the impact of hominin stone exploitation are rare and inherently difficult. The Messak Settafet, a sandstone massif in the Central Sahara (Libya), is littered with Pleistocene stone tools on an unprecedented scale and is, in effect, a man-made landscape. Surveys showed that parts of the Messak Settafet have as much as 75 lithics per square metre and that this fractured debris is a dominant element of the environment. The type of stone tools--Acheulean and Middle Stone Age--indicates that extensive stone tool manufacture occurred over the last half million years or more. The lithic-strewn pavement created by this ancient stone tool manufacture possibly represents the earliest human environmental impact at a landscape scale and is an example of anthropogenic change. The nature of the lithics and inferred age may suggest that hominins other than modern humans were capable of unintentionally modifying their environment. The scale of debris also indicates the significance of stone as a critical resource for hominins and so provides insights into a novel evolutionary ecology.

Show MeSH
Related in: MedlinePlus