“许家窑人”埋藏地层与时代探讨

“许家窑人”化石发现于河北省阳原县泥河湾盆地西端的侯家窑遗址。该遗址20世纪70年代历经数次发掘,发现古人类化石20件、石制品数万件以及大量的哺乳动物化石。虽然已有大量关于遗址的研究成果发表,但人类化石和考古遗物的出土地层仍有些模糊,文化层时代也存在较大争议;年代数据在20 kaBP到500 kaBP的大范围间变化,影响学者们对“许家窑人”及其文化遗存演化位置的认识。鉴于此,河北省文物研究所（现河北省文物考古研究院）在2007~2012年对该遗址开展了持续的考古调查及发掘,重要目的之一在于廓清遗址埋藏的地貌部位和文化层的分布状况等基本信息。侯家窑遗址的地层包含上、下两个文化层;下文化层以下2~3 m（距地表约14.5 m）处确认了不整合接触面,其下为泥河湾层堆积,之上为河流阶地堆积。综合对20世纪70年代发掘的地层描述、新发掘地层以及人类化石保存状态的认识,“许家窑人”化石应出自遗址地层沉积序列的上文化层中,而非湖相的泥河湾层中。通过对目前遗址已有测年数据的重新梳理,我们认为,上文化层即“许家窑人”化石的时代为200~160 kaBP,主要对应深海氧同位素6阶段早期;下文化层的准确年代仍需验证,目前光释光年龄为198±15 kaBP, ²⁶Al/ ¹⁰Be埋藏年代为240±50 kaBP。     

What's in a beach? Soil micromorphology of sediments from the Lower Paleolithic site of 'Ubeidiya, Israel

A micromorphological study of archaeological sediments from the early Pleistocene site of 'Ubeidiya (Jordan Valley, Israel) was conducted to provide microenvironmental detail for the hominin occupation contexts and investigate site formation issues. Previous research shows that the hominin groups occupied the marshes and pebbly beaches at the shores of a lake during a regressive period, but given that some portions of the lithic and faunal assemblages are abraded and others fresh, there remains a question of whether the archaeological assemblages are in situ or reworked, and if reworked, by what mechanisms and from where. The rates of sedimentation within the regressive cycle, by which we can learn about the frequency and duration of exposed surfaces amenable for hominin occupation is also unknown. Finally, the artificial nature of some of the pebbly layers has been questioned. The micromorphological analysis yielded the identification of twelve microfacies; the majority of these represent fluvially derived floodplain soils or distal mudflow deposits, and a minor number are sediments of lacustrine origin: mudflats and shallow subaqueous sediments. These represent the natural habitats of the 'Ubeidiya hominins and might serve as a reference to similar contexts of other early hominin sites. The sedimentary model proposed here entails the rapid deposition of fluvially derived low-energy sediments at and around the shoreline, followed by prolonged periods of exposure, during which surfaces stabilized within a relatively wet, marshy environment. This interpretation suggests that the abraded portions of the archaeological assemblages are a result of prolonged surface exposure rather than high-energy transport from a distant source or to wave reworking at the shoreline, and supports the consideration of these assemblages as archaeological palimpsests, with locally reworked fresh and abraded elements. No micromorphological evidence supporting anthropogenic agency in the formation of the pebbly layers was found. The entire regressive cycle entailed unvarying climatic conditions with seasonal fluctuations and episodic lacustrine incursions, and with a trend towards arid conditions in the end.     

中国古人类活动遗址形成过程研究的进展与思考

中国境内分布着数千处古人类活动遗址,是早期人类演化与适应行为研究的重要区域.虽然以往的研究一直关注地学手段在解读遗址地貌和地层形成过程中的作用,然而,作为正确鉴别遗址完整性和早期人类生存行为研究的遗址形成过程(或遗址成因)分析,长期以来缺少系统性的研究和关键指标的选择.本文结合古人类活动遗址保存的地貌和主要沉积物类型,...     

Paleogeographic variations of pedogenic carbonate delta13C values from Koobi Fora, Kenya: implications for floral compositions of Plio-Pleistocene hominin environments

Plio-Pleistocene East African grassland expansion and faunal macroevolution, including that of our own lineage, are attributed to global climate change. To further understand environmental factors of early hominin evolution, we reconstruct the paleogeographic distribution of vegetation (C(3)-C(4) pathways) by stable carbon isotope (delta(13)C) analysis of pedogenic carbonates from the Plio-Pleistocene Koobi Fora region, northeast Lake Turkana Basin, Kenya. We analyzed 202 nodules (530 measurements) from ten paleontological/archaeological collecting areas spanning environments over a 50-km(2) area. We compared results across subregions in evolving fluviolacustrine depositional environments in the Koobi Fora Formation from 2.0-1.5 Ma, a stratigraphic interval that temporally brackets grassland ascendancy in East Africa. Significant differences in delta(13)C values between subregions are explained by paleogeographic controls on floral composition and distribution. Our results indicate grassland expansion between 2.0 and 1.75 Ma, coincident with major shifts in basin-wide sedimentation and hydrology. Hypotheses may be correct in linking Plio-Pleistocene hominin evolution to environmental changes from global climate; however, based on our results, we interpret complexity from proximate forces that mitigated basin evolution. An approximately 2.5 Ma tectonic event in southern Ethiopia and northern Kenya exerted strong effects on paleography in the Turkana Basin from 2.0-1.5 Ma, contributing to the shift from a closed, lacustrine basin to one dominated by open, fluvial conditions. We propose basin transformation decreased residence time for Omo River water and expanded subaerial floodplain landscapes, ultimately leading to reduced proportions of wooded floras and the establishment of habitats suitable for grassland communities.     

Carbonate horizons, paleosols, and lake flooding cycles: Beds I and II of Olduvai Gorge, Tanzania

This study documents the petrology and stable isotope geochemistry of carbonates from six horizons from Beds I and II of Olduvai Gorge, Tanzania. The studied succession, immediately below and above Tuff IF, consists of interbedded waxy and earthy claystones with discrete carbonate horizons and thin sandstones. The succession was deposited in response to repeated flooding and withdrawal of a saline-alkaline lake. The carbonates and their overlying disconformities are important because they help define the surfaces on which hominin activity took place and allow very high-resolution correlation of geographically separated levels of hominin exploitation.The range of different carbonates includes unambiguous land-surface and pedogenic features including calcified rootmat horizons, rhizocretions, and micritic nodules, together with less determinate sparry calcite nodules. Stellate nodules are interpreted as pseudomorphs after sulfate-roses. The carbonate nodules are synsedimentary features, truncated by fluvial and other erosional surfaces. The isotopic composition of the carbonates is variable with δ¹⁸O ranging from −7.0‰ to −4.3‰, and δ¹³C from −8.5‰ to −1.6‰. A covariant increase in δ¹³C and δ¹⁸O repeats in each carbonate horizon and in individual nodules (inner to outer layers): it reflects the evolution of synsedimentary groundwaters. At times of low lake level, the carbonates started to precipitate from meteoric waters with low isotopic values and continued to form as lake levels rose and the waters became increasingly saline. Some of the samples have a last-stage cement of strontium rich dolomite, which supports late-stage flooding by the saline-alkaline lake. Previous studies of carbonate horizons from Olduvai have interpreted carbon isotope values in terms of changes in C₃ and C₄ plants that colonized the land surface. This study demonstrates that in some instances the isotope values from carbonates deposited in these lake marginal settings reflect changes in hydrology rather than vegetation.     

泥河湾盆地板井子旧石器时代遗址的形成过程

板井子遗址是泥河湾盆地晚更新世早期的一处重要遗址,光释光年代为距今8～9万年.本文以2015年出土的考古材料为研究对象,从地层的沉积环境、考古材料本体的埋藏特点两个角度,对板井子遗址的形成过程进行分析.分析表明,主文化层第5层为近原地埋藏类型,水流作用对小尺寸标本的保存及标本的空间集聚特征影响较大,但石制品技术类型组合...     

Les nodules sphériques de basalte de l’unité archéologique US2 du site de « Bois-de-Riquet », France : origine et caractérisation d’une sélection

Sometimes represented in high percentages, manuports constitute an important component of the tools in Lower Pleistocene sites. As such, they greatly participate in the established models for the understanding of Plio-Pleistocene hominin behaviour and territorial organization in Africa and Europe. However, their role among this component remains hypothetical. The lithic assemblage of US2 at the Bois-de-Riquet site has yielded 100 nodules. Their abnormal presence in the context of the cavity questions the anthropic nature of their introduction and therefore of their possible use. The BDR industry is therefore participating in the open debate on the function of manuports. The main objective here is to demonstrate that these objects, although originating from local formation, are neither produced in the cavity, nor introduced naturally, but that they have been the object of an anthropic contribution among the lithic assemblage within the bone remains and probably related to them. The anthropic introduction of natural nodules from several local sources will be demonstrated here. For this, sampling was carried out in all local volcanic contexts where nodules are naturally present in a primary or secondary position. Each of these samples has been compared to the archaeological artefacts from US2. A local historical anthropic context, where these nodules were used for building a roman road, completes this comparison to serve as an anthropic reference. The results demonstrate the anthropic introduction of basalt balls into the US2 of Bois-de-Riquet site and also make possible the identification of raw material sources in which US2 lithic assemblage was selected.     

旧石器时代旷野遗址形成过程研究综述

遗址形成过程(或成因)研究是以地质考古学的研究手段为出发点,解读古人类遗址的形成和埋藏过程,其研究结果对正确解读遗址完整性和早期人类生存行为具有重要意义。该研究方向在中国尚未引起足够重视,这在一定程度上降低了我国古人类学和旧石器时代考古学学术研究的国际影响力。鉴于旷野遗址在保存早期人类化石及遗物方面的特殊地位,本文以地质考古学为出发点,系统分析有关旷野遗址形成过程研究所涉及的科学问题,对Glynn Isaac在东非创立的一套系统解读旷野遗址形成过程研究所涉及的指标进行梳理。此外,作者以古人类活动遗物的埋藏和空间分布特征为切入点,详细介绍目前从事旷野遗址成因研究所涉及的关键指标及学术意义,并对中国境内有关遗址成因研究以及旷野遗址形成过程研究的历史与现状进行讨论。     

The evolving landscape and climate of western Flores: an environmental context for the archaeological site of Liang Bua

The rapidly changing landscape of the eastern Indonesian archipelago has evolved at a pace dictated by its tropical climate and its geological and tectonic history. This has produced accelerated karstification, flights of alluvial terraces, and complex, multi-level cave systems. These cave systems sometimes contain a wealth of archaeological evidence, such as the almost complete skeleton of Homo floresiensis found at the site of Liang Bua in western Flores, but this information can only be understood in the context of the geomorphic history of the cave, and the more general geological, tectonic, and environmental histories of the river valley and region. Thus, a reconstruction of the landscape history of the Wae Racang valley using speleothems, geological structure, tectonic uplift, karst, cave, and terrace development, provides the necessary evidence to determine the formation, age, evolution, and influences on the site. This evidence suggests that Liang Bua was formed as two subterranean chambers ∼600 ka, but could not be occupied until ∼190 ka when the Wae Racang wandered to the southern side of the valley, exposing the chamber and depositing alluvial deposits containing artifacts. During the next ∼190 k.yr., the chambers coalesced and evolved into a multi-level and interconnected cave that was subjected to channel erosion and pooling events by the development of sinkholes. The domed morphology of the front chamber accumulated deep sediments containing well stratified archaeological and faunal remains, but ponded water in the chamber further prevented hominin use of the cave until ∼100 ka. These chambers were periodically influenced by river inundation and volcanic activity, whereas the area outside the cave was greatly influenced by glacial phases, which changed humid forest environments into grassland environments. This combined evidence has important implications for the archaeological interpretation of the site.     

蔚县盆地吉家庄旧石器遗址的形成过程

泥河湾盆地发育着我国北方第四纪典型的河湖相沉积体系,因其间富集众多早-中更新世旧石器时代遗址为学术界所关注。本文对泥河湾盆地蔚县吉家庄遗址（JJZ-B和JJZ-E地点）的遗址成因进行分析。地貌和沉积物特点表明,JJZ-B地点埋藏于湖滨相环境的湿地或沼泽环境,JJZ-E地点则属于湖滨相环境下的沙坝沉积体系。遗物的多项指标（遗物空间分布特点、石制品风化磨蚀状况、石制品技术组合与空间产状特征等）分析显示,JJZ-B地点属于近原地埋藏,形成过程中受到微弱的入湖片流改造,遗址完整性较高;JJZ-E地点的遗物连同砾石被湖滨片流搬运至遗址堆积区,后期受到了湖水的淘洗作用,显示异地埋藏的特点。研究表明,泥河湾古湖在中更新世仍保留有丰富的古人类活动信息,湖滨不同部位对遗址成因产生重要影响;该研究对正确解读古人类对吉家庄遗址不同地点的利用方式具有重要意义。     

Early Evidence of Acheulean Settlement in Northwestern Europe - La Noira Site,a 700 000 Year-Old Occupation in the Center of France

The human settlement of Europe during Pleistocene times was sporadic and several stages have been recognized, both from paleaoanthropological and archaeological records. If the first phase of hominin occupation (as early as 1.4 Ma) seems mainly restricted to the southern part of the continent, the second phase, characterized by specific lithic tools (handaxes), is linked to Acheulean settlements and to the emergence of Homo heidelbergensis, the ancestor of Neanderthals. This phase reached northwestern Europe and is documented in numerous sites in Germany, Great Britain and northern France, generally after 600 ka.At la Noira (Brinay, Central France), the Middle Pleistocene alluvial formation of the Cher River covers an archaeological level associated with a slope deposit (diamicton). The lithic assemblage from this level includes Large Cutting Tools (LCTs), flakes and cores, associated with numerous millstone slabs. The lithic series is classified as Acheulean on the basis of both technological and typological analyses. Cryoturbation features indicate that the slope deposits and associated archaeological level were strongly frozen and disturbed after hominin occupation and before fluvial deposition. Eight sediment samples were dated by the electron spin resonance (ESR) method and the weighted average age obtained for the fluvial sands overlying the slope deposits is 665±55 ka. This age is older than previous chronological data placing the first European Acheulean assemblages north of 45^th parallel north at around 500 ka and modifies our current vision of the initial peopling of northern Europe. Acheulean settlements are older than previously assumed and the oldest evidences are not only located in southern Europe. La Noira is the oldest evidence of Acheulean presence in north-western Europe and attests to the possibility of pioneering phases of Acheulean settlement which would have taken place on a Mode 1-type substratum as early as 700 ka. The lithic assemblage from la Noira thus provides behavioral and technological data on early Acheulean occupation in Europe and contributes to our understanding of the diffusion of this tradition.     

Earliest Archaeological Evidence of Persistent Hominin Carnivory

The emergence of lithic technology by ∼2.6 million years ago (Ma) is often interpreted as a correlate of increasingly recurrent hominin acquisition and consumption of animal remains. Associated faunal evidence, however, is poorly preserved prior to ∼1.8 Ma, limiting our understanding of early archaeological (Oldowan) hominin carnivory. Here, we detail three large well-preserved zooarchaeological assemblages from Kanjera South, Kenya. The assemblages date to ∼2.0 Ma, pre-dating all previously published archaeofaunas of appreciable size. At Kanjera, there is clear evidence that Oldowan hominins acquired and processed numerous, relatively complete, small ungulate carcasses. Moreover, they had at least occasional access to the fleshed remains of larger, wildebeest-sized animals. The overall record of hominin activities is consistent through the stratified sequence – spanning hundreds to thousands of years – and provides the earliest archaeological evidence of sustained hominin involvement with fleshed animal remains (i.e., persistent carnivory), a foraging adaptation central to many models of hominin evolution.     

Stabilization of carbon in mineral soils from mangroves of the Sinú river delta,Colombia

Mangrove forests of the Sinú river delta in Cispatá bay, Colombia, show large differences in soil carbon storage between fringe (oceanic) and basin (estuarine) mangroves. We were interested in testing whether these differences in soil carbon are associated with sediment transport processes or whether most of the carbon is produced in situ within the mangrove system. Given past sedimentation dynamics of the Sinú river, we hypothesized that a large portion of soil carbon in basin mangroves is due to sedimentation. We determined total organic carbon content (TOC) as 660.93 ± 259.18 MgC ha^?1 for basin soils up to a sampling depth of 1 m, and as 259 ± 42.61 MgC ha^?1 for fringe soils up to 80 cm depth (maximum soil depth for fringe soils). Using analyses of mineralogy (Al- and Fe-oxides, clay minerals) as well as isotopic analyses of carbon (δ¹³C), the origin of the sediments and their carbon was determined. We found that basin soils in Cispatá bay show similar mineralogical composition than those of fluvial sediments, but the carbon concentration of river sediments was close to zero. Given the large capacity of the Fe and Al oxides in clay minerals to store dissolved carbon, and that the isotopic composition of the carbon is mostly of plant origin, we concluded contrary to our initial hypothesis that the carbon stored in basin mangrove soils are produced in situ. The deposited fluvial sediments do play an important role for carbon storage, but mostly in providing binding surfaces for the stabilization of organic carbon.     

Reconstructing Mid-Pleistocene paleovegetation and paleoclimate in the Golan Heights using the δ(13)C values of modern vegetation and soil organic carbon of paleosols

The Golan Heights borders the Upper Jordan Valley on its eastern side and likely served as a prime foraging area for hominin groups that inhabited the Upper Jordan Valley during the Mid-Pleistocene. This study tests the hypothesis that Mid-Pleistocene climate in the Golan region was similar to that of the present day. Carbon isotope composition of present day plant communities and soil organic carbon from the Golan were compared to those of paleosols from Nahal Orvim to reconstruct Mid-Pleistocene paleoclimatic conditions. After correcting the paleosol values for recent changes in atmospheric carbon isotope values and potential biodegradation, the isotopic results show a strong similarity to those of present day local plants and soils. These results indicate that during the Mid-Pleistocene, the Golan was dominated by C₃ vegetation, shared similar climatic conditions with the present day, and displayed long-term environmental stability. The span of time of paleosol formation is unknown and might cover multiple climatic episodes; thus, although short climatic fluctuations may have occurred, their impact was not substantial enough to be detected in the Nahal Orvim paleosols. This study concludes that the Golan slopes provided hominins and large grazers with a reliable and highly nutritious foraging area that complemented the Jordan Valley riparian ecosystem.     

Stable isotopes of pedogenic carbonates as indicators of paleoecology in the Plio-Pleistocene (upper Bed I), western margin of the Olduvai Basin, Tanzania

Paleosol carbonates from trenches excavated as part of a landscape-scale project in Bed I of Olduvai Gorge, Tanzania, were analyzed for stable carbon and oxygen isotopic composition. The approximately 60,000-year interval ( approximately 1.845-1.785 Ma) above Tuff IB records evidence for lake and fluvial sequences, volcanic eruptions, eolian and pedogenic processes, and the development of a fluvial plain in the western margin of the basin. Significant temporal variation in the carbonate delta(18)O values records variation of local precipitation and supports the shifts in climatic conditions interpreted from the lithologic record. During this period, carbonate delta(13)C values varied between depositional facies indicating that the paleolandscape supported a local biomass of about 40-60% C(4) plants within a mosaic of grassy woodlands and wooded grasslands. The lithologic and stable isotope record in this small lake basin indicates the area was much wetter, with more woody C(3) plants, during this interval than is the semi-arid area today. The record also reflects the variation in climatic conditions (wet/dry) documented by other global climate proxies for this time.     

Long-distance carcass transport at Olduvai Gorge? A quantitative examination of Bed I skeletal element abundances

Relative abundances of skeletal elements at Plio-Pleistocene archaeological sites have long been interpreted to represent selective transport of portions of large prey. Models from optimal foraging theory suggest that the degree of carcass transport selectivity reflects transport constraints, particularly transport distance. A quantitative analysis of skeletal element abundances in five bone assemblages from Bed I, Olduvai Gorge, indicates that within the subset of elements most likely to resist attritional processes, there is no evidence for preferential transport of small or large mammals. The results suggest relatively low carcass transport costs and are most consistent with site formation models favoring short-distance carcass transport. The data are also consistent with the possibility that hominins were not responsible for transporting bones at some sites. Several Bed I assemblages, with the exception of FLK-Zinjanthropus, lack evidence of a functional relationship between flaked stone artifacts and the faunal remains, such as cut-marks or percussion-marks on bone. In conjunction with the skeletal part data, this suggests that hominin involvement with the bone assemblages was minimal at all sites but FLK-Zinjanthropus. The patterning at Bed I contrasts strongly with Middle Stone Age and Middle Paleolithic assemblages, which provide clear evidence for selective transport, suggesting higher transport costs and longer transport distances.     

沉积物特征与旧石器遗址的形成过程

考古遗址在自然因素下所经历的沉积、改造和再堆积过程,对于理解遗址完整历史至关重要,但迄今相关研究在中国旧石器遗址中开展得较为有限。本文在介绍遗址堆积与改造过程相关背景知识的基础上,对自然因素研究中涉及到的最为关键和核心的对象之一——沉积物及其常用分析指标(粒度、磁化率、地球化学元素、矿物组成和土壤微形态)进行阐述,并以许昌人遗址和伞顶盖遗址为例说明相关指标的应用情况。沉积物分析指标侧重从微观角度揭示旧石器遗址的堆积与改造过程,因此,我们还需结合宏观尺度下的遗址沉积地层、地貌发育和环境演变等特征,以及考古标本本身的一系列信息对遗址在自然因素影响下的形成过程进行综合分析和判断。     

Pedogenic carbonate stable isotopic evidence for wooded habitat preference of early Pleistocene tool makers in the Turkana Basin

The origin and evolution of early Pleistocene hominin lithic technologies in Africa occurred within the context of savanna grassland ecosystems. The Nachukui Formation of the Turkana Basin in northern Kenya, containing Oldowan and Acheulean tool assemblages and fossil evidence for early members of Homo and Paranthropus, provides an extensive spatial and temporal paleosol record of early Pleistocene savanna flora. Here we present new carbon isotopic (δ¹³C_VPDB) values of pedogenic carbonates (68 nodules, 193 analyses) from the Nachukui Formation in order to characterize past vegetation structure and change through time. We compared three members (Kalochoro, Kaitio, and Natoo) at five locations spanning 2.4–1.4 Ma and sampled in proximity to hominin archaeological and paleontological sites. Our results indicate diverse habitats showing a mosaic pattern of vegetation cover at each location yet demonstrate grassland expansion through time influenced by paleogeography. Kalochoro floodplains occurred adjacent to large river systems, and paleosols show evidence of C₃ woodlands averaging 46–50% woody cover. Kaitio habitats were located along smaller rivers and lake margins. Paleosols yielded evidence for reduced portions of woody vegetation averaging 34–37% woody cover. Natoo environments had the highest percentage of grasslands averaging 21% woody cover near a diminishing Lake Turkana precursor. We also compared paleosol δ¹³C_VPDB values of lithic archaeological sites with paleosol δ¹³C_VPDB values of all environments available to hominins at 2.4–1.4 Ma in the Nachukui and Koobi Fora Formations. Grassy environments became more widespread during this interval; woody canopy cover mean percentages steadily decreased by 12%. However, significantly more wooded savanna habitats were present in the vicinity of lithic archaeological sites and did not mirror the basin-wide trend of grassland spread. Hominin lithic archaeological sites consistently demonstrated woody cover circa 40% throughout our study interval and were 4–12% more woody than coeval basin environs. We propose that Turkana Basin early tool makers may have preferred a more wooded portion of the savanna ecosystem to reduce heat stress and to gain differential access to potable water, raw materials, animal carcasses, and edible plants.     

甘肃徐家城遗址石制品原料最小单元分析

徐家城遗址是甘肃省近年来发掘的一处旧石器时代晚期遗址,主要埋藏于陇西盆地水洛河二级阶地上覆的马兰黄土中,年代在距今约4.6~2.3万年间。本文使用原料最小单元分析这一目前国内尚未普及的方法对该遗址主文化层的石制品进行研究,涉及遗址形成过程、空间利用以及古人类的流动组织等方面。研究表明,古人类原地剥片行为是遗址主文化层石制品分布状态形成的主要原因,文化层交界位置所受扰动程度较大;石器工业面貌权宜性色彩较为浓厚,发掘区内并未呈现明显的功能分区,同一时期可能存在其他生活中心。本文对原料最小单元分析方法的适用性和潜力作了一定讨论。     

The carbon isotope ecology and diet of Australopithecus africanus at Sterkfontein,South Africa

The stable carbon isotope ratio of fossil tooth enamel carbonate is determined by the photosynthetic systems of plants at the base of the animal's foodweb. In subtropical Africa, grasses and many sedges have C(4)photosynthesis and transmit their characteristically enriched 13C/(12)C ratios (more positive delta13C values) along the foodchain to consumers. We report here a carbon isotope study of ten specimens of Australopithecus africanus from Member 4, Sterkfontein (ca. 2.5 to 2.0Ma), compared with other fossil mammals from the same deposit. This is the most extensive isotopic study of an early hominin species that has been achieved so far. The results show that this hominin was intensively engaged with the savanna foodweb and that the dietary variation between individuals was more pronounced than for any other early hominin or non-human primate species on record. Suggestions that more than one species have been incuded in this taxon are not supported by the isotopic evidence. We conclude that Australopithecus africanus was highly opportunistic and adaptable in its feeding habits.