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Earliest burial of a modern human in Africa

by M. Martinón Torres, Nature May 2021

The origin and evolution of hominin mortuary practices are topics of intense interest and debate. Human burials dated to the Middle Stone Age (MSA) are exceedingly rare in Africa and unknown in East Africa. Here we describe the partial skeleton of a roughly 2.5- to 3.0-year-old child dating to 78.3 ± 4.1 thousand years ago, which was recovered in the MSA layers of Panga ya Saidi (PYS), a cave site in the tropical upland coast of Kenya. Recent excavations have revealed a pit feature containing a child in a flexed position. Geochemical, granulometric and micromorphological analyses of the burial pit content and encasing archaeological layers indicate that the pit was deliberately excavated. Taphonomical evidence, such as the strict articulation or good anatomical association of the skeletal elements and histological evidence of putrefaction, support the in-place decomposition of the fresh body. The presence of little or no displacement of the unstable joints during decomposition points to an interment in a filled space (grave earth), making the PYS finding the oldest known human burial in Africa. The morphological assessment of the partial skeleton is consistent with its assignment to Homo sapiens, although the preservation of some primitive features in the dentition supports increasing evidence for non-gradual assembly of modern traits during the emergence of our species. The PYS burial sheds light on how MSA populations interacted with the dead.

New Hybrid Bone Reveals that Neanderthals and Denisovans Mated

The closest known extinct relatives of modern humans were the thick-browed Neanderthals and the mysterious Denisovans. Now, a bone fragment from a Siberian cave, perhaps from a teenage girl, has revealed the first known hybrid of these groups, a new study concludes. The finding confirms interbreeding that had been only hinted at in earlier genetic studies.

Archaeological excavations have revealed that Neanderthals and Denisovans coexisted in Eurasia, with Neanderthal bones ranging from 200,000 to 40,000 years old unearthed mostly in western Eurasia and Denisovans so far only known from fossils ranging from 200,000 to 30,000 years old found in eastern Eurasia. Prior work unearthed Neanderthal remains in Denisova Cave, raising questions on how closely they interacted.

The Denisovan father of the individual Denisova 11 had at least one Neanderthal ancestor, possibly as far back as 300 to 600 generations before his lifetime. In addition, the teenage girl’s Neanderthal mother was genetically more similar to the Neanderthals of Western Europe than to a different Neanderthal that lived earlier in Denisova Cave. This find suggests that Neanderthals migrated between western and eastern Eurasia for tens of thousands of years.

Viviane Slon, Fabrizio Mafessoni, … Svante Pääbo

Nature (2018) The genome of the offspring of a Neanderthal mother and a Denisovan father.

Homo erectus Were Technologically Conservative, Used Least-Effort Strategies

Archaeological excavations at the Acheulean site of Saffaqah near Dawadmi in central Saudi Arabia have found that Homo erectus, an extinct hominid species that lived between 1.9 million and 143,000 years ago, used ‘least-effort strategies’ for tool making and collecting resources.

C. Shipton et al. 2018. Acheulean technology and landscape use at Dawadmi, central Arabia. PLoS ONE 13 (7): e0200497; doi: 10.1371/journal.pone.0200497

13 million-year-old infant ape skull discovered in the Turkana Basin

The discovery in Kenya of a remarkably complete fossil ape skull reveals what the common ancestor of all living apes and humans may have looked like. The find, announced in the scientific journal Nature on August 10th, belongs to an infant that lived about 13 million years ago. The research was done by an international team led by Isaiah Nengo of the Turkana Basin Institute and De Anza College, USA.

300.000 years old modern humans at Jebel Irhoud

Nature 546, 289–292 (08 June 2017) doi:10.1038/nature22336

The idea that modern people evolved in a single “cradle of humanity” in East Africa some 200,000 years ago is no longer tenable, new research suggests. Fossils of five early humans have been found in North Africa that show Homo sapiens emerged at least 100,000 years earlier than previously recognised. 

Potential hominin affinities of Graecopithecus from the Late Miocene of Europe

  • Fuss J, Spassov N, Begun DR, Böhme M (2017) Potential hominin affinities of Graecopithecus from the Late Miocene of Europe. PLoS ONE 12(5): e0177127. doi:10.1371/journal.pone.0177127.

The split of our own clade from the Panini is undocumented in the fossil record. To fill this gap we investigated the dentognathic morphology of Graecopithecus freybergi from Pyrgos Vassilissis (Greece) and cf. Graecopithecus sp. from Azmaka (Bulgaria), using new μCT and 3D reconstructions of the two known specimens. Pyrgos Vassilissis and Azmaka are currently dated to the early Messinian at 7.175 Ma and 7.24 Ma. Mainly based on its external preservation and the previously vague dating, Graecopithecus is often referred to as nomen dubium. The examination of its previously unknown dental root and pulp canal morphology confirms the taxonomic distinction from the significantly older northern Greek hominine Ouranopithecus. Furthermore, it shows features that point to a possible phylogenetic affinity with hominins. G. freybergi uniquely shares p4 partial root fusion and a possible canine root reduction with this tribe and therefore, provides intriguing evidence of what could be the oldest known hominin.

Naledi fossils dated to 236-335 kya

Homo naledi lived sometime between 335 and 236 thousand years ago. A second chamber in the Rising Star cave system, which contained additional specimens includes a child and the partial skeleton of an adult male with a well-preserved skull that has been named “Neo” – a Sesotho word meaning “a gift”.

  • Homo naledi and Pleistocene hominin evolution in subequatorial Africa. Berger LR, Hawks J, Dirks PH, Elliott M, Roberts EM. Elife. 2017 May 9;6. pii: e24234. doi: 10.7554/eLife.24234.

New Middle Pleistocene hominin cranium from Gruta da Aroeira (Portugal)

The Middle Pleistocene is a crucial time period for studying human evolution in Europe, because it marks the appearance of both fossil hominins ancestral to the later Neandertals and the Acheulean technology. Nevertheless, European sites containing well-dated human remains associated with an Acheulean toolkit remain scarce. The earliest European hominin crania associated with Acheulean handaxes are at the sites of Arago, Atapuerca Sima de los Huesos (SH), and Swanscombe, dating to 400–500 ka (Marine Isotope Stage 11–12). The Atapuerca (SH) fossils and the Swanscombe cranium belong to the Neandertal clade, whereas the Arago hominins have been attributed to an incipient stage of Neandertal evolution, to Homo heidelbergensis, or to a subspecies of Homo erectus. A recently discovered cranium (Aroeira 3) from the Gruta da Aroeira (Almonda karst system, Portugal) dating to 390–436 ka provides important evidence on the earliest European Acheulean-bearing hominins. This cranium is represented by most of the right half of a calvarium (with the exception of the missing occipital bone) and a fragmentary right maxilla preserving part of the nasal floor and two fragmentary molars. The combination of traits in the Aroeira 3 cranium augments the previously documented diversity in the European Middle Pleistocene fossil record.

Daura J, et al (2017) PNAS Early Edition | 1 of 6  http://www.pnas.org/cgi/doi/10.1073/pnas.1619040114

The diet of the first Europeans from Atapuerca

The Homo antecessor, a hominin species that inhabited the Iberian Peninsula around 800,000 years ago, would have a mechanically more demanding diet than other hominin species in Europe and the African continent. This unique pattern, which would be characterized by the consumption of hard and abrasive foods, may be explained by the differences in food processing in a very demanding environment with fluctuations in climate and food resources, according to a study published in the journal Scientific Reports and led by a team from the Faculty of Biology of the University of Barcelona, the Catalan Institute of Human Paleoecology and Social Evolution (IPHES) and the University of Alicante.

This new research, which reveals for the first time the evidence on the diet of these hominines with the study of the microscopic traces left by food in the dental enamel, counts with the participation of the researchers Alejandro Pérez-Pérez and his team, formed by the doctors Laura Martínez, Ferrán Estebaranz, and Beatriz Pinilla (UB), Marina Lozano (Catalan Institute of Human Paleoecology and Social Evolution, IPHES), Alejandro Romero (University of Alicante), Jordi Galbany (George Washington University, United States) and the co-directors of Atapuerca, José María Bermúdez de Castro (National Research Centre on Human Evolution, CENIEH), Eudald Carbonell (IPHES) and Juan Luís Arsuaga (Universidad Complutense de Madrid).

Prior to this research, the diet of the hominines of the Lower Pleistocene of Atapuerca (Burgos, Spain), our most remote European ancestors, had been inferred from animal remains –a great variety of large mammals and even turtles– found in the same levels in which the human remains were found. Evidence of cannibalism has also been suggested in some of these fossils.

Foods that leave a mark on the dental enamel

The study is based on the analysis of the buccal microwear pattern of the fossils from Trinchera  Elefante and Gran Dolina in the Atapuerca site. The examined microwear features are small marks on the buccal teeth enamel surface , whose density and length depend on the types of chewed food. “The usefulness of this methodology has been proved by the study of the microwear patterns of present populations, both hunter-gatherer and agricultural, showing that different feeding patterns correlate with specific microwear patterns in the vestibular surface of the dental crown”, explains Professor Alejandro Pérez-Pérez, professor at the Zoology and Biological Anthropology Unit of theof the Department of Evolutionary Biology, Ecology and Environmental Sciences at the University of Barcelona.

In the new study, the Atapuerca fossils have been compared with samples from other Lower Pleistocene populations: with fossils of the African Homo ergaster, ancestors of all Europeans dated from 1.8 million years ago; and also with Homo heidelbergensis, which appeared more than 500,000 years ago in Europe and lasted until at least 200,000 years ago, and finally with Homo neanderthalensis, specimens from the Iberian Peninsula that lived between 200,000 and 40,000 years ago.

Higher striation densities in Homo antecessor

The results of the study show that the teeth of H. antecessor show higher striation densities than the rest of the analyzed species. “Our findings do not allow us to say exactly what foods they ate, since the abrasive materials that cause the marks on the teeth may have different origins, but they do allow us to point out that H. antecessor would have had a diet largely based on hard and abrasive foods, such as plants containing phytoliths (which are silica particles produced by plants that are as hard as enamel), tubers with traces of soil particles, collagen or connective tissue and bone or raw meat”, says the researcher.

The researchers suggest that differences in the Gran Dolina microwear patterns among the compared samples could reflect cultural differences in the way food was processed. “Hunting and gathering activities are consistent with the highly-abrasive wear pattern we have encountered, but it is very difficult to think that the available food in the Atapuerca area was very different from that available to other hunter-gatherer hominins. Therefore, it would be the different ways of processing the food that would give rise to these differences in the dental microwear patterns. That is to say, they obtained, processed and consumed the food in different ways”, explains Alejandro Pérez-Pérez, who leads a team that has also applied this methodology in the study of feeding behaviors of the hominins of the Pleistocene of East Africa, including the species Paranthropus boisei and Homo habilis.

A more primitive lithic industry

This pattern of great abrasiveness, observed on the enamel teeth surfaces in Gran Dolina contrasts with what has been observed in the compared species in the study. “Unlike H. neanderthalensis, which had a more advanced lithic industry (called Mode 3 or Mousterian), the tools that have been found related to Homo antecessor are primitive (Mode 1). These industries would not facilitate food processing, as also suggested by evidence that they used teeth to chew bones. In addition, the lack of evidence of the use of fire in Atapuerca suggests that they would surely eat everything raw, causing more dental wear, including plant foods, meat, tendons or skin.

For the researchers, a diet with a high meat consumption could have evolutionary implications. “Meat in the diet could have contributed to the necessary energy gain to sustain a large brain like that of H. antecessor, with a brain volume of approximately 1,000 cubic centimeters, compared to the 764 of H. ergaster, but it would also represent a significant source of food in a highly demanding environment where preferred foods, such as ripe fruits and tender vegetables, would vary seasonally”.

The research contributes significantly to the better understanding of the dietary adaptations of our ancestors and highlights the importance of the ecological and cultural factors that have conditioned our biological evolution.

Paper reference:

A. Pérez-Pérez, M. Lozano, A. Romero, L. M. Martínez, J. Galbany, B. Pinilla, F. Estebaranz-Sánchez, J. M. Bermúdez de Castro, E. Carbonell i J. L. Arsuaga. «The diet of the first Europeans from Atapuerca». Scientific Reports, February 2017.

The Diet of t 1.2 ma Sima del Elefante hominin revealed through analysis of dental calculus

Dental calculus from a hominin molar from the Sima del Elefante site (Atapuerca, Burgos) shows evidence for plant use at 1.2 ma, including starchy carbohydrates from a species of grass from the Triticeae or Bromideae tribe that was eaten raw. There is no evidence for processing of the starch granules which are intact and undamaged. Additional evidence includes fragments of non-edible wood found adjacent to an interproximal groove suggesting oral hygiene activities.

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