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Re: НАУЧНЫЕ факты и комментарии

Продолжение...
Интересные факты по эволюции гоминид,

установленные в последние годы (1997-2004)

Источники:


1. Br J Nutr. 1998 Jan;79(1):3-21.

Rift Valley lake fish and shellfish provided brain-specific nutrition for early Homo.

Broadhurst CL, Cunnane SC, Crawford MA.

An abundant, balanced dietary intake of long-chain polyunsaturated fatty acids is an absolute requirement for sustaining the very rapid expansion of the hominid cerebral cortex during the last one to two million years. The brain contains 600 g lipid/kg, with a long-chain polyunsaturated fatty acid profile containing approximately equal proportions of arachidonic acid and docosahexaenoic acid. Long-chain polyunsaturated fatty acid deficiency at any stage of fetal and/or infant development can result in irreversible failure to accomplish specific components of brain growth. For the past fifteen million years, the East African Rift Valley has been a unique geological environment which contains many enormous freshwater lakes. Paleoanthropological evidence clearly indicates that hominids evolved in East Africa, and that early Homo inhabited the Rift Valley lake shores. Although earlier hominid species migrated to Eurasia, modern Homo sapiens is believed to have originated in Africa between 100 and 200 thousand years ago, and subsequently migrated throughout the world. A shift in the hominid resource base towards more high-quality foods occurred approximately two million years ago; this was accompanied by an increase in relative brain size and a shift towards modern patterns of fetal and infant development. There is evidence for both meat and fish scavenging, although sophisticated tool industries and organized hunting had not yet developed. The earliest occurrences of modern H. sapiens and sophisticated tool technology are associated with aquatic resource bases. Tropical freshwater fish and shellfish have long-chain polyunsaturated lipid ratios more similar to that of the human brain than any other food source known. Consistent consumption of lacustrine foods could have provided a means of initiating and sustaining cerebral cortex growth without an attendant increase in body mass. A modest intake of fish and shellfish (6-12% total dietary energy intake) can provide more arachidonic acid and especially more docosahexaenoic acid than most diets contain today. Hence, 'brain-specific' nutrition had and still has significant potential to affect hominid brain evolution.

2. J Hum Evol. 2000 Apr;38(4):497-521.

Adults only. Reindeer hunting at the middle palaeolithic site salzgitter lebenstedt, northern Germany.

Gaudzinski S, Roebroeks W.

The Middle Palaeolithic site Salzgitter Lebenstedt (northern Germany), excavated in 1952, is well known because of its well-preserved faunal remains, dominated by adult reindeer (Rangifer tarandus). The archaeological assemblage accumulated in an arctic setting in an earlier part of the last (Weichsel) glacial (OIS5-3). The site is remarkable because of the presence of unique Middle Palaeolithic bone tools and the occurrence of the northernmost Neanderthal remains, but this paper focuses on an analysis of its reindeer assemblage. The results indicate autumn hunting of reindeer by Middle Palaeolithic hominids. After the hunt, carcasses were butchered and in subsequent marrow processing of the bones a selection against young and sub-adult animals occurred. Adults were clearly preferred, and from their bones, again, poorer marrow bones were neglected. This focus on primeness of resources has been documented in other domains of Neanderthal behaviour, but Salzgitter Lebenstedt is the best example yet known in terms of systematic and routinized processing of game. The Salzgitter Lebenstedt assemblage displays some remarkable similarities to the Late Glacial reindeer assemblages from the Ahrensburg tunnel valley sites. The subsequent review of the evidence on subsistence strategies from earlier periods of the European Palaeolithic shows that hunting of large mammals may have been a part of the behavioural repertoire of the Middle Pleistocene occupants of Europe from the earliest occupation onwards. At the same time, it is suggested that these early hunting strategies were incorporated in ways of moving through landscapes ("settlement systems") which were different from what we know from the middle parts of the Upper Palaeolithic onwards. Copyright 2000 Academic Press.

3. J Hum Evol. 1998 Aug;35(2):111-36.

A critique of the evidence for scavenging by Neanderthals and early modern humans: new data from Kobeh Cave (Zagros Mountains, Iran) and Die Kelders Cave 1 layer 10 (South Africa).

Marean CW.

The primary mode of faunal exploitation by Neandertals and early modern humans remains a debated topic. Binford (1981, 1984, 1985, 1988) has argued for an obligate scavenging mode, Stiner (1991a, 1991b, 1991c, 1993, 1994) for a more opportunistic scavenging mode, while other researchers (Chase, 1986, 1988, 1989; Klein, 1989, 1994, 1995; Klein & Cruz-Uribe, 1996) deny the importance of scavenging as a faunal exploitation tactic. The scavenging interpretations rely primarily on several patterns in the faunal remains: the presence of a skeletal element pattern dominated by heads or head and foot parts, the presence of carnivore tooth marks on bone fragments, and infrequent cut marks that typically are not located on shaft regions of long bones or on fleshy bones. Five sites have been used to argue for scavenging: Klasies River Mouth, Combe Grenal, Grotta Guattari, Grotta dei Moscerini, and Grotte Vaufrey. The former four of the five sites are biased samples in that long bone shafts and other difficult to identify fragments were discarded at excavation. The analysis of Grotte Vaufrey included only those shafts identifiable to species or genus, thus excluding the vast majority of shaft specimens. This bias systematically shapes the skeletal element and surface modification patterning in ways that make the assemblages appear to fit a model of scavenging, when in fact the main determinant of the pattern is the bias in the flawed samples. This problem is illustrated with two unbiased faunal assemblages (Kobeh Cave and Die Kelders Layer 10). Skeletal element abundance is calculated in a way that mimics the bias in the sites listed above by excluding the shafts. Using this procedure, both Kobeh and Die Kelders have a head and foot skeletal element pattern and thus appear scavenged. Both assemblages are then analyzed in their entirety and a new pattern, consistent with hunting, is revealed. Taphonomic data on bone survival and destruction provide an explanation for this result. Excluding shaft fragments from the analysis also biases the surface modification patterning in such a way as to produce a pattern more consistent with scavenging. The conclusion is that there is no reliable evidence for scavenging by Neandertals or early modern humans.

4. Published online before print June 13, 2000, 10.1073/pnas.120178997
Proc Natl Acad Sci U S A. 2000 June 20; 97 (13): 7663–7666
Anthropology

Neanderthal diet at Vindija and Neanderthal predation: The evidence from stable isotopes

5. J Hum Evol. 2002 Dec;43(6):831-72.

Male strategies and Plio-Pleistocene archaeology.

O'Connell JF, Hawkes K, Lupo KD, Blurton Jones NG.

Archaeological data are frequently cited in support of the idea that big game hunting drove the evolution of early Homo, mainly through its role in offspring provisioning. This argument has been disputed on two grounds: (1) ethnographic observations on modern foragers show that although hunting may contribute a large fraction of the overall diet, it is an unreliable day-to-day food source, pursued more for status than subsistence; (2) archaeological evidence from the Plio-Pleistocene, coincident with the emergence of Homo can be read to reflect low-yield scavenging, not hunting. Our review of the archaeology yields results consistent with these critiques: (1) early humans acquired large-bodied ungulates primarily by aggressive scavenging, not hunting; (2) meat was consumed at or near the point of acquisition, not at home bases, as the hunting hypothesis requires; (3) carcasses were taken at highly variable rates and in varying degrees of completeness, making meat from big game an even less reliable food source than it is among modern foragers. Collectively, Plio-Pleistocene site location and assemblage composition are consistent with the hypothesis that large carcasses were taken not for purposes of provisioning, but in the context of competitive male displays. Even if meat were acquired more reliably than the archaeology indicates, its consumption cannot account for the significant changes in life history now seen to distinguish early humans from ancestral australopiths. The coincidence between the earliest dates for Homo ergaster and an increase in the archaeological visibility of meat eating that many find so provocative instead reflects: (1) changes in the structure of the environment that concentrated scavenging opportunities in space, making evidence of their pursuit more obvious to archaeologists; (2) H. ergaster's larger body size (itself a consequence of other factors), which improved its ability at interference competition.

6. Proc Natl Acad Sci U S A. 2001 February 13; 98 (4): 1358–1363
Evidence of termite foraging by Swartkrans early hominids
Lucinda R. Backwell and Francesco d'Errico

Previous studies have suggested that modified bones from the Lower Paleolithic sites of Swartkrans and Sterkfontein in South Africa represent the oldest known bone tools and that they were used by Australopithecus robustus to dig up tubers. Macroscopic and microscopic analysis of the wear patterns on the purported bone tools, pseudo bone tools produced naturally by known taphonomic processes, and experimentally used bone tools confirm the anthropic origin of the modifications. However, our analysis suggests that these tools were used to dig into termite mounds, rather than to dig for tubers. This result indicates that early hominids from southern Africa maintained a behavioral pattern involving a bone tool material culture that may have persisted for a long period and strongly supports the role of insectivory in the early hominid diet.

7. Homo. 2003;54(1):1-28.
Early hominin speciation at the Plio/Pleistocene transition.
Cameron DW.

Over the last half-decade or so, there has been an explosion in the recognition of hominin genera and species. We now have the late Miocene genera Orrorin and Sahelanthropus, the mid Pliocene genus Kenyanthropus, three new Pliocene species of Australopithecus (A. anamensis, A. garhi and A. bahrelghazali) and a sub species of Ardipithecus (Ar. r. kadabba) to contend with. Excepting also the more traditional species allocated to Paranthropus, Australopithecus and early Homo we are approaching around 15 species over 5 million years (excluding hominin evolution over the last one million years). Can such a large number of hominin species be justified? An examination of extant hominid (Gorilla gorilla, Pan troglodytes, and Pan paniscus) anatomical variability indicates that the range of fossil hominin variability supports the recognition of this large number of fossil species. It is also shown that not all hominins are directly related to the emergence of early Homo and as such have become extinct. Indeed the traditional australopithecine species 'A'. anamensis, 'A'. afarensis and 'A'. garhi are considered here to belong to a distinct genus Praeanthropus. They are also argued not be hominins, but rather an as yet undefined hominid group from which the more derived hominins evolved. The first hominin is represented by A. africanus or a hominin very much like it. The Paranthropus clade is defined by a derived heterochronic condition of peramorphosis, associated with sequential progenesis (contraction of successive growth stages) in brain and dental development, but a mixture of peramorphic and paedomorphic features in its craniofacial anatomy. Conversely, Kenyanthropus and Homo both share a pattern of peramorphosis, associated with sequential hypermorphosis (prolongation of successive growth stages) in brain development, and paedomorphosis processes in cranial, facial and dental development. This suggests, that these two clades share an important synapomorphy not recognised in the parsimony analyses, suggesting that they may form a sister group relationship to the exclusion of Paranthropus. This highlights the need to re-interpret phylogenetic results in terms of function and development. The rapid speciation and extinction as argued here is in keeping with other fossil groups in Africa at the Plio/Pleistocene transition. This emphasises that we must approach the pre-australopithecines and hominins as part of the endemic African fauna, and not in isolation to the evolutionary and climatic processes that were operating all around them.

8. Первоописание Ardipithecus kadabba.

Nature. 2001 Jul 12;412(6843):178-81.
Late Miocene hominids from the Middle Awash, Ethiopia.
Haile-Selassie Y.

Molecular studies suggest that the lineages leading to humans and chimpanzees diverged approximately 6.5-5.5 million years (Myr) ago, in the Late Miocene. Hominid fossils from this interval, however, are fragmentary and of uncertain phylogenetic status, age, or both. Here I report new hominid specimens from the Middle Awash area of Ethiopia that date to 5.2-5.8 Myr and are associated with a wooded palaeoenvironment. These Late Miocene fossils are assigned to the hominid genus Ardipithecus and represent the earliest definitive evidence of the hominid clade. Derived dental characters are shared exclusively with all younger hominids. This indicates that the fossils probably represent a hominid taxon that postdated the divergence of lineages leading to modern chimpanzees and humans. However, the persistence of primitive dental and postcranial characters in these new fossils indicates that Ardipithecus was phylogenetically close to the common ancestor of chimpanzees and humans. These new findings raise additional questions about the claimed hominid status of Orrorin tugenensis, recently described from Kenya and dated to approximately 6 Myr.

9. Science. 2004 Mar 5;303(5663):1503-5.
Late Miocene teeth from Middle Awash, Ethiopia, and early hominid dental evolution.
Haile-Selassie Y, Suwa G, White TD.

Late Miocene fossil hominid teeth recovered from Ethiopia's Middle Awash are assigned to Ardipithecus kadabba. Their primitive morphology and wear pattern demonstrate that A. kadabba is distinct from Ardipithecus ramidus. These fossils suggest that the last common ancestor of apes and humans had a functionally honing canine-third premolar complex. Comparison with teeth of Sahelanthropus and Orrorin, the two other named late Miocene hominid genera, implies that these putative taxa are very similar to A. kadabba. It is therefore premature to posit extensive late Miocene hominid diversity on the basis of currently available samples.

10. Nature. 1997 Feb 27;385(6619):807-10.
Lower Palaeolithic hunting spears from Germany.
Thieme H.

Little is known about the organic component of Lower and Middle Palaeolithic technologies, particular with respect to wooden tools. Here I describe some wooden throwing spears about 400,000 years old that were discovered in 1995 at the Pleistocene site at Schöningen, Germany. They are thought to be the oldest complete hunting weapons so far discovered to have been used by humans. Found in association with stone tools and the butchered remains of more than ten horses, the spears strongly suggest that systematic hunting, involving foresight, planning and the use of appropriate technology, was part of the behavioural repertoire of pre-modern hominids. The use of sophisticated spears as early as the Middle Pleistocene may mean that many current theories on early human behaviour and culture must be revised.
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