scispace - formally typeset
Search or ask a question
Author

Hélène Roche

Bio: Hélène Roche is an academic researcher from University of Paris. The author has contributed to research in topics: Oldowan & Acheulean. The author has an hindex of 18, co-authored 27 publications receiving 2248 citations. Previous affiliations of Hélène Roche include Centre national de la recherche scientifique.

Papers
More filters
Journal ArticleDOI
21 May 2015-Nature
TL;DR: The discovery of Lomekwi 3 is reported, a 3.3-million-year-old archaeological site where in situ stone artefacts occur in spatiotemporal association with Pliocene hominin fossils in a wooded palaeoenvironment and the name ‘Lomekwian’ is proposed, which predates the Oldowan by 700,000 years and marks a new beginning to the known archaeological record.
Abstract: Human evolutionary scholars have long supposed that the earliest stone tools were made by the genus Homo and that this technological development was directly linked to climate change and the spread of savannah grasslands. New fieldwork in West Turkana, Kenya, has identified evidence of much earlier hominin technological behaviour. We report the discovery of Lomekwi 3, a 3.3-million-year-old archaeological site where in situ stone artefacts occur in spatiotemporal association with Pliocene hominin fossils in a wooded palaeoenvironment. The Lomekwi 3 knappers, with a developing understanding of stone's fracture properties, combined core reduction with battering activities. Given the implications of the Lomekwi 3 assemblage for models aiming to converge environmental change, hominin evolution and technological origins, we propose for it the name 'Lomekwian', which predates the Oldowan by 700,000 years and marks a new beginning to the known archaeological record.

631 citations

Journal ArticleDOI
01 Sep 2011-Nature
TL;DR: Co-occurrence of Oldowan and Acheulian artefacts at the Kokiselei site complex indicates that the two technologies are not mutually exclusive time-successive components of an evolving cultural lineage, and suggests that multiple groups of hominins distinguished by separate stone-tool-making behaviours and dispersal strategies coexisted in Africa at 1.76 Myr ago.
Abstract: The Acheulian is one of the first defined prehistoric technocomplexes and is characterized by shaped bifacial stone tools. It probably originated in Africa, spreading to Europe and Asia perhaps as early as 1 million years (Myr) ago. The origin of the Acheulian is thought to have closely coincided with major changes in human brain evolution, allowing for further technological developments. Nonetheless, the emergence of the Acheulian remains unclear because well-dated sites older than 1.4Myr ago are scarce. Here we report on the lithic assemblage and geological context for the Kokiselei 4 archaeological site fromthe Nachukui formation(West Turkana,Kenya) that bears characteristic early Acheulian tools and pushes the first appearance datumfor this stone-age technology back to 1.76Myr ago. Moreover, co-occurrence of Oldowan and Acheulian artefacts at the Kokiselei site complex indicates that the two technologies are not mutually exclusive time-successive components of an evolving cultural lineage, and suggests that the Acheulian was either imported from another location yet to be identified or originated from Oldowan hominins at this vicinity. In either case, the Acheulian did not accompany the first human dispersal from Africa despite being available at the time. This may indicate that multiple groups of hominins distinguished by separate stone-tool-making behaviours and dispersal strategies coexisted in Africa at 1.76Myr ago.

373 citations

Journal ArticleDOI
06 May 1999-Nature
TL;DR: A technological analysis of the core reduction sequences is described, based on these refits, which allows unprecedented accuracy in the understanding of flake production processes and can demonstrate greater cognitive capacity and motor skill than previously assumed for early hominids.
Abstract: Well-documented Pliocene archaeological sites are exceptional. At present they are known only in East Africa, in the Hadar1,2 and Shungura3 formations of Ethiopia and in the Nachukui formation of Kenya. Intensive archeological survey and a series of test excavations conducted in the Nachukui formation since 1987 have led to the discovery of more than 25 archaeological sites whose ages range from 2.34 to 0.7 million years before present (Myr)4,5, and to the extensive excavation of two 2.34-Myr sites, Lokalalei 1 in 1991 (refs 6, 7) and Lokalalei 2C in 1997. Lokalalei 2C yielded nearly 3,000 archaeological finds from a context of such good preservation that it was possible to reconstitute more than 60 sets of complementary matching stone artefacts. These refits, predating the Koobi Fora refits by 500 Kyr (ref. 8), are the oldest ever studied. Here we describe a technological analysis of the core reduction sequences, based on these refits, which allows unprecedented accuracy in the understanding of flake production processes. We can thus demonstrate greater cognitive capacity and motor skill than previously assumed for early hominids, and highlight the diversity of Pliocene technical behaviour.

317 citations

Journal ArticleDOI
TL;DR: The data suggest that early hominids displayed distinct technical competencies and techno-economic patterns of behavior, thus pointing to an intrasite complexity and intersite diversity which are not accounted for by the existing chrono-cultural classifications.

297 citations

Journal ArticleDOI
TL;DR: Hominin fossil evidence in the Turkana Basin in Kenya from ca.
Abstract: Hominin fossil evidence in the Turkana Basin in Kenya from ca. 4.1 to 1.4 Ma samples two archaic early hominin genera and records some of the early evolutionary history of Paranthropus and Homo. Stable carbon isotopes in fossil tooth enamel are used to estimate the fraction of diet derived from C3 or C4 resources in these hominin taxa. The earliest hominin species in the Turkana Basin, Australopithecus anamensis, derived nearly all of its diet from C3 resources. Subsequently, by ca. 3.3 Ma, the later Kenyanthropus platyops had a very wide dietary range—from virtually a purely C3 resource-based diet to one dominated by C4 resources. By ca. 2 Ma, hominins in the Turkana Basin had split into two distinct groups: specimens attributable to the genus Homo provide evidence for a diet with a ca. 65/35 ratio of C3- to C4-based resources, whereas P. boisei had a higher fraction of C4-based diet (ca. 25/75 ratio). Homo sp. increased the fraction of C4-based resources in the diet through ca. 1.5 Ma, whereas P. boisei maintained its high dependency on C4-derived resources.

177 citations


Cited by
More filters
01 Jan 1980
TL;DR: In this article, the influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition and found that the variability of the relationship between the δ^(15)N values of animals and their diets is greater for different individuals raised on the same diet than for the same species raised on different diets.
Abstract: The influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition. The isotopic composition of the nitrogen in an animal reflects the nitrogen isotopic composition of its diet. The δ^(15)N values of the whole bodies of animals are usually more positive than those of their diets. Different individuals of a species raised on the same diet can have significantly different δ^(15)N values. The variability of the relationship between the δ^(15)N values of animals and their diets is greater for different species raised on the same diet than for the same species raised on different diets. Different tissues of mice are also enriched in ^(15)N relative to the diet, with the difference between the δ^(15)N values of a tissue and the diet depending on both the kind of tissue and the diet involved. The δ^(15)N values of collagen and chitin, biochemical components that are often preserved in fossil animal remains, are also related to the δ^(15)N value of the diet. The dependence of the δ^(15)N values of whole animals and their tissues and biochemical components on the δ^(15)N value of diet indicates that the isotopic composition of animal nitrogen can be used to obtain information about an animal's diet if its potential food sources had different δ^(15)N values. The nitrogen isotopic method of dietary analysis probably can be used to estimate the relative use of legumes vs non-legumes or of aquatic vs terrestrial organisms as food sources for extant and fossil animals. However, the method probably will not be applicable in those modern ecosystems in which the use of chemical fertilizers has influenced the distribution of nitrogen isotopes in food sources. The isotopic method of dietary analysis was used to reconstruct changes in the diet of the human population that occupied the Tehuacan Valley of Mexico over a 7000 yr span. Variations in the δ^(15)C and δ^(15)N values of bone collagen suggest that C_4 and/or CAM plants (presumably mostly corn) and legumes (presumably mostly beans) were introduced into the diet much earlier than suggested by conventional archaeological analysis.

5,548 citations

Journal Article
TL;DR: In this article, a categorization of weathering characteristics into six stages, recognizable on descriptive criteria, provides a basis for investigation of the weathering rates and processes of recent mammals in the Amboseli Basin.
Abstract: Bones of recent mammals in the Amboseli Basin, southern Kenya, exhibit distinctive weathering characteristics that can be related to the time since death and to the local conditions of temperature, humidity and soil chemistry. A categorization of weathering characteristics into six stages, recognizable on descriptive criteria, provides a basis for investigation of weathering rates and processes. The time necessary to achieve each successive weathering stage has been calibrated using known-age carcasses. Most bones decompose beyond recognition in 10 to 15 yr. Bones of animals under 100 kg and juveniles appear to weather more rapidly than bones of large animals or adults. Small-scale rather than widespread environmental factors seem to have greatest influence on weathering characteristics and rates. Bone weathering is potentially valuable as evidence for the period of time represented in recent or fossil bone assemblages, in- cluding those on archeological sites, and may also be an important tool in censusing populations of animals in modern ecosystems.

2,035 citations

Journal ArticleDOI
TL;DR: In this paper, the best dated and most complete African mammal fossil databases indicate African faunal assemblage and speciation changes during the Pliocene-Pleistocene interval (the last ca. 5.3 million years) were mediated by changes in African climate or shifts in climate variability.

1,127 citations

Journal ArticleDOI
02 Mar 2001-Science
TL;DR: This work has shown that stone tool technology, robust australopithecines, and the genus Homo appeared almost simultaneously 2.5 million years ago, and once this adaptive threshold was crossed, technological evolution was accompanied by increased brain size, population size, and geographical range.
Abstract: Human biological and cultural evolution are closely linked to technological innovations. Direct evidence for tool manufacture and use is absent before 2.5 million years ago (Ma), so reconstructions of australopithecine technology are based mainly on the behavior and anatomy of chimpanzees. Stone tool technology, robust australopithecines, and the genus Homo appeared almost simultaneously 2.5 Ma. Once this adaptive threshold was crossed, technological evolution was accompanied by increased brain size, population size, and geographical range. Aspects of behavior, economy, mental capacities, neurological functions, the origin of grammatical language, and social and symbolic systems have been inferred from the archaeological record of Paleolithic technology.

643 citations

Journal ArticleDOI
21 May 2015-Nature
TL;DR: The discovery of Lomekwi 3 is reported, a 3.3-million-year-old archaeological site where in situ stone artefacts occur in spatiotemporal association with Pliocene hominin fossils in a wooded palaeoenvironment and the name ‘Lomekwian’ is proposed, which predates the Oldowan by 700,000 years and marks a new beginning to the known archaeological record.
Abstract: Human evolutionary scholars have long supposed that the earliest stone tools were made by the genus Homo and that this technological development was directly linked to climate change and the spread of savannah grasslands. New fieldwork in West Turkana, Kenya, has identified evidence of much earlier hominin technological behaviour. We report the discovery of Lomekwi 3, a 3.3-million-year-old archaeological site where in situ stone artefacts occur in spatiotemporal association with Pliocene hominin fossils in a wooded palaeoenvironment. The Lomekwi 3 knappers, with a developing understanding of stone's fracture properties, combined core reduction with battering activities. Given the implications of the Lomekwi 3 assemblage for models aiming to converge environmental change, hominin evolution and technological origins, we propose for it the name 'Lomekwian', which predates the Oldowan by 700,000 years and marks a new beginning to the known archaeological record.

631 citations