Anna Maria Mercuri

Lakeside Cemeteries in the Sahara: 5000 Years of Holocene Population and Environmental Change

Background Approximately two hundred human burials were discovered on the edge of a paleolake in Niger that provide a uniquely preserved record of human occupation in the Sahara during the Holocene (∼8000 B.C.E. to the present). Called Gobero, this suite of closely spaced sites chronicles the rapid pace of biosocial change in the southern Sahara in response to severe climatic fluctuation. Methodology/Principal Findings Two main occupational phases are identified that correspond with humid intervals in the early and mid-Holocene, based on 78 direct AMS radiocarbon dates on human remains, fauna and artifacts, as well as 9 OSL dates on paleodune sand. The older occupants have craniofacial dimensions that demonstrate similarities with mid-Holocene occupants of the southern Sahara and Late Pleistocene to early Holocene inhabitants of the Maghreb. Their hyperflexed burials compose the earliest cemetery in the Sahara dating to ∼7500 B.C.E. These early occupants abandon the area under arid conditions and, when humid conditions return ∼4600 B.C.E., are replaced by a more gracile people with elaborated grave goods including animal bone and ivory ornaments. Conclusions/Significance The principal significance of Gobero lies in its extraordinary human, faunal, and archaeological record, from which we conclude the following: The early Holocene occupants at Gobero (7700–6200 B.C.E.) were largely sedentary hunter-fisher-gatherers with lakeside funerary sites that include the earliest recorded cemetery in the Sahara. Principal components analysis of craniometric variables closely allies the early Holocene occupants at Gobero with a skeletally robust, trans-Saharan assemblage of Late Pleistocene to mid-Holocene human populations from the Maghreb and southern Sahara. Gobero was abandoned during a period of severe aridification possibly as long as one millennium (6200–5200 B.C.E). More gracile humans arrived in the mid-Holocene (5200–2500 B.C.E.) employing a diversified subsistence economy based on clams, fish, and savanna vertebrates as well as some cattle husbandry. Population replacement after a harsh arid hiatus is the most likely explanation for the occupational sequence at Gobero. We are just beginning to understand the anatomical and cultural diversity that existed within the Sahara during the Holocene.

A high resolution late Holocene palaeo environmental record from the central Adriatic Sea

A multi-proxy study of a Holocene sediment core (RF 93-30) from the western flank of the central Adriatic, in 77 m of water, reveals a sequence of changes in terrestrial vegetation, terrigenous sediment input and benthic fauna, as well as evidence for variations in sea surface temperature spanning most of the last 7000 yr. The chronology of sedimentation is based on several lines of evidence, including AMS 14C dates of foraminifera extracted from the core, palaeomagnetic secular variation, pollen indicators and dated tephra. The temporal resolution increases towards the surface and, for some of the properties measured, is sub-decadal for the last few centuries. The main changes recorded in vegetation, sedimentation and benthic foraminiferal assemblages appear to be directly related to human activity in the sediment source area, which includes the Po valley and the eastern flanks of the central and northern Appenines. The most striking episodes of deforestation and expanding human impact begin around 3600 BP (Late Bronze Age) and 700 BP (Medieval) and each leads to an acceleration in mass sedimentation and an increase in the proportion of terrigenous material, reflecting the response of surface processes to widespread forest clearance and cultivation. Although human impact appears to be the proximal cause of these changes, climatic effects may also have been important. During these periods, signs of stress are detectable in the benthic foram morphotype assemblages. Between these two periods of increased terrigeneous sedimentation there is smaller peak in sedimentation rate around 2400BP which is not associated with evidence for deforestation, shifts in the balance between terrigenous and authigenic sedimentation, or changes in benthic foraminifera. The mineral magnetic record provides a sensitive indicator of changing sediment sources: during forested periods of reduced terrigenous input it is dominated by authigenic bacterial magnetite, whereas during periods of increased erosion, anti-ferromagetic minerals (haematite and/or goethite) become more important, as well as both paramagnetic minerals and super-paramagnetic magnetite. Analysis of the alkenone, U37k′, record provides an indication of possible changes in sea surface temperature during the period, but it is premature to place too much reliance on these inferred changes until the indirect effects of past changes in the depth of the halocline and in circulation have been more fully evaluated. The combination of methods used and the results obtained illustrate the potential value of such high resolution near-shore marine sedimentary sequences for recording wide-scale human impact, documenting the effects of this on marine sedimentation and fauna and, potentially, disentangling evidence for human activities from that for past changes in climate.

Mediterranean and north-African cultural adaptations to mid-Holocene environmental and climatic changes

In Mediterranean and north-African regions, cultural trajectories have shown trends sometimes coincident with climatic changes. The mid Holocene was a period of intense changes in climate, and in environmental and cultural systems. This paper reports pollen and charcoal studies from these areas aiming at presenting how impressive cultural changes frequently coincided with critical climate oscillations. Three of the main dry events of key relevance for climatic—cultural changes were selected to discuss this topic: c. 8200 cal. yr BP, c. 6000 cal. yr BP, and c. 4200 cal. yr BP. Five examples from on-site case studies were reported: (1) Wadi Teshuinat area (Fezzan, Libya, Central Sahara); (2) Benzù cave (Ceuta mountains, Spain, NW Africa); (3) La Vaquera Cave (Central System, Spain); (4) Terramara di Montale (Po Plain, Northern Italy); (5) Arslantepe (Eastern Anatolia, Turkey). Their archaeobotanical record helps to recognise and date human presence and activity in different territories. In these examples, anthropogenic signals and comparisons with other sites could be useful to distinguish climate signal from human impact in pollen records. Charcoals are evidence of human activity in cases which are not shown by pollen. Overexploitation of thinned plant resources, including overgrazing, accelerated the evolution towards xeric conditions during drying climatic phases. Humans enforced the aridity crisis and enhanced its signal in palaeoclimatic records. Sometimes, changing exploitation strategies and movements led to the onset of new cultures. Nevertheless, the onset and decline of a culture are very different critical phases, and different agents must have been involved in their occurrence. The Bronze Age marked the environment more than the Neolithic, probably because there is a relation between improvements in knowledge, cultural changes and the evolution of complex forms of land exploitation.

Reconstructing past cultural landscape and human impact using pollen and plant macroremains

Abstract Three examples of plant landscape shaping, carried out by Iron Age populations living in different geographical areas, are presented. The examples differ in population type (Garamantes, Etruscans, and Romans), archaeological context (settlement, necropolis, furnace, port), and area of plant exploitation (respectively, Fezzan – Libyan Sahara and Tuscany, Latium – central Italy). The leitmotiv of the three parallel investigations highlighted that humans induced clear changes in plant cover modifying the quantitative ratio among native elements and spreading the plants of economic interest even outside of their natural habitats. Micro- and macroremain analyses once more enhanced that landscape reconstruction depends on both wild and cultivated plants, and that the cultural plant landscape is composed of a complex mixture of indigenous and exotic elements. Archaeobotany results in great help in reviewing ancient prejudices, rewriting history in a modern ecological view, also discovering a different role in the landscape evolution of past civilizations. In this light, the Garamantes deeply transformed the oases in agrarian producer sites, and the Etruscans, in the area of the Gulf of Follonica, modified the previous forest vegetation, probably enhancing the xeric features. The Romans, believed as the main creators of the environmental changes in the Mediterranean basin, surprisingly did not produce consistent plant changes in the area of the Tiber delta, in the surroundings of the imperial port of Rome, during the first century AD.

The European Modern Pollen Database (EMPD) project

Modern pollen samples provide an invaluable research tool for helping to interpret the quaternary fossil pollen record, allowing investigation of the relationship between pollen as the proxy and the environmental parameters such as vegetation, land-use, and climate that the pollen proxy represents. The European Modern Pollen Database (EMPD) is a new initiative within the European Pollen Database (EPD) to establish a publicly accessible repository of modern (surface sample) pollen data. This new database will complement the EPD, which at present holds only fossil sedimentary pollen data. The EMPD is freely available online to the scientific community and currently has information on almost 5,000 pollen samples from throughout the Euro-Siberian and Mediterranean regions, contributed by over 40 individuals and research groups. Here we describe how the EMPD was constructed, the various tables and their fields, problems and errors, quality controls, and continuing efforts to improve the available data.

Editorial: Archaeobotany for cultural landscape and human impact reconstructions

Editorial: Archaeobotany for cultural landscape and human impact reconstructions Anna Maria Mercuri a , Laura Sadori b & Carlo Blasi b a Laboratorio di Palinologia e Paleobotanica, Dipartimento di Biologia, Universita di Modena e Reggio Emilia, v.le Caduti in Guerra 127, 41121, Modena, Italy b Dipartimento di Biologia Ambientale, Universita di Roma “La Sapienza”, piazzale A. Moro 5, 00185, Roma, Italy

Inside the “African Cattle Complex”: Animal Burials in the Holocene Central Sahara

Cattle pastoralism is an important trait of African cultures. Ethnographic studies describe the central role played by domestic cattle within many societies, highlighting its social and ideological value well beyond its mere function as ‘walking larder’. Historical depth of this African legacy has been repeatedly assessed in an archaeological perspective, mostly emphasizing a continental vision. Nevertheless, in-depth site-specific studies, with a few exceptions, are lacking. Despite the long tradition of a multi-disciplinary approach to the analysis of pastoral systems in Africa, rarely do early and middle Holocene archaeological contexts feature in the same area the combination of settlement, ceremonial and rock art features so as to be multi-dimensionally explored: the Messak plateau in the Libyan central Sahara represents an outstanding exception. Known for its rich Pleistocene occupation and abundant Holocene rock art, the region, through our research, has also shown to preserve the material evidence of a complex ritual dated to the Middle Pastoral (6080–5120 BP or 5200–3800 BC). This was centred on the frequent deposition in stone monuments of disarticulated animal remains, mostly cattle. Animal burials are known also from other African contexts, but regional extent of the phenomenon, state of preservation of monuments, and associated rock art make the Messak case unique. GIS analysis, excavation data, radiocarbon dating, zooarchaeological and isotopic (Sr, C, O) analyses of animal remains, and botanical information are used to explore this highly formalized ritual and the lifeways of a pastoral community in the Holocene Sahara.

Pollen from archaeological layers and cultural landscape reconstruction: Case studies from the Bradano valley (Basilicata, southern Italy)

Abstract The article aims at presenting some aspects of environmental reconstruction through pollen analysis from archaeological contexts. The anthropogenic pollen transport into archaeological sites is regarded as an interesting tool to improve knowledge on flora and vegetation in the area of influence of sites. The zoophilous plants can be found more easily than in the regional airborne pollen rain where anemophilous pollen is generally overrepresented. Moreover, pollen from archaeological contexts is mainly a result of the cultural landscape shaped by human activities. Two case studies from the Bradano Valley (Basilicata, southern Italy), rich in archaeological sites dating altogether from the Middle Bronze Age to the Medieval age, are reported. Difesa San Biagio and its surroundings is one of the biggest settlements of the area, settled in early times by Enotrians. Altojanni is an extended area mainly frequented in Hellenistic, Roman late Imperial and Medieval times. A very open landscape, and clear signs of plant exploitation and cultivation, breeding and settlements were present in the two sites. Though samples are disturbed and preservation problems are sometimes observed, the main characters of pollen spectra are recurrent. High percentages of Poaceae and Cichorioideae, together with coprophilous fungal spores, strongly suggest a long tradition of pastoral activities. These case study examples suggest that human activities would have produced a fairly xeric environment.

Archaeobotany for cultural landscape and human impact reconstructions

Editorial: Archaeobotany for cultural landscape and human impact reconstructions Anna Maria Mercuri a , Laura Sadori b & Carlo Blasi b a Laboratorio di Palinologia e Paleobotanica, Dipartimento di Biologia, Universita di Modena e Reggio Emilia, v.le Caduti in Guerra 127, 41121, Modena, Italy b Dipartimento di Biologia Ambientale, Universita di Roma “La Sapienza”, piazzale A. Moro 5, 00185, Roma, Italy

Honey bees and their products as indicators of environmental radioactive pollution

Samples of honey, pollen and honey bees have been collected in some regions of Italy after the Chernobyl accident, and subjected to gamma spectrometry in order to assess their possible use as markers of the radioactive environmental contamination. Pollen has resulted in the best indicator, since it reflects exactly the air contamination and therefore it is suitable for obtaining a map of fallout. Also bees can be used for the purpose, even if their collection is more difficult, whereas honey gives only an indication.