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TOPIC: Homo Sapiens
Blobrana


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Iberomaurusians
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The skeleton of a man belonging to an ancient prehistoric culture, found recently by a team of Moroccan and German archaeologists in a cave in the province of Nador, is being exhibited in an international exhibition in Bonn, Germany, from Aug.8-Dec.19, announced a press release from the Ministry of Culture.
The skeleton belonged to a population called 'Iberomaurusian', which occupied North Africa between 22,000 and 9,000 years ago. The skeleton is part of an exhibition entitled 'At the roots of humanity'. The Ministry's press release said that "it is the whole of the human, technical or scientific adventure of palaeontology and archaeology which will be presented to the public" in the Rheinisches Landes Museum of Bonn.
The skeleton was unearthed in the cave of Ifri n'Ammer, in the Commune of Afsou, Nador province, by an archaeological team jointly directed by the researchers Abdeslam Mikdad, of the National Institute of Archaeological and Heritage Sciences (INSAP), and Josef Eiwanger, of the German Archaeological Institut (KAAK, DAI).

"16,000 years ago, this strongly-built man (1.78m in height), aged between 21 and 25, was buried in a sitting position in a small trench. The incisors teeth of his upper jaw had been removed, following the Iberomaurusian custom, probably as a passage rite on reaching adulthood" - Ministry press release.

The Iberomaurusian culture was first recognised in Morocco in the Grotte des Pigeons, in the Beni Snassen area near Oujda. The cave, extensively excavated for many years, has yielded much important information concerning the lives of these early Moroccans.

Source Morocco Times

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Blobrana


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Posts: 131433
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Neanderthal DNA
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HE is 38,000 years old and nothing but a pile of bones, but one day we may be able to rebuild him. Scientists are planning to reconstruct the genetic code of Neanderthal man.

Anthropologists plan to apply the forensic techniques used to map the human genome to chart all 3 billion chemical “base-pairs” in the DNA of man’s close but long-dead relative.
The researchers believe the DNA of the two species is 99.96% the same, but will not attempt to recreate a living Neanderthal in the laboratory.
Once all the genes and their correct order are known, cloning would theoretically be possible in the future — just as scientists have talked of resurrecting the mammoth from extinction using DNA samples.
Scientists in Germany and America have already decoded 1m DNA base-pairs from the leg bone of a fossilised Neanderthal found in a cave in Croatia.
They believe that if they can crack his entire code it will help explain the differences between Neanderthals and humans and give clues how to prevent disease and illness.
The two-year project has been launched at the Max Planck Institute in Leipzig, Germany. Researchers led by Svante Paabo, a Swedish anthropologist who was the first to extract DNA from a Neanderthal fossil, will chip away the top layer of bone and use a dentist’s drill to collect samples.
Most Neanderthal remains are so old that the DNA has been contaminated by bacteria or the touch of archaeologists.
In some cases only 3% of the DNA in the remains is Neanderthal, but the fossil found in Croatia is largely uncontaminated.

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Blobrana


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Australia Footprints
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About 20,000 years ago, humans trekked along the margins of a shallow lake in Australia, leaving behind records of their passage in the soft, wet sand.

In 2003, an aboriginal woman who is likely a descendant of those early Australians stumbled across dozens of timeworn footprints in the same area. Excavations of the site have since uncovered hundreds more.

The discovery, detailed in a recent issue of the Journal of Human Evolution, represents the largest collection of Pleistocene human footprints in the world, and the only footprints from that era ever found in Australia. In total, 457 footprints have now been uncovered.

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Blobrana


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Migration
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The continent-hopping habits of early primates have long puzzled scientists, and several scenarios have been proposed to explain how the first true members of the group appeared virtually simultaneously on Asia, Europe and North America some 55 million years ago.

But new research using the latest evidence suggests a completely different migration path from those previously proposed and indicates that sudden, rapid global warming drove the dispersal.
Researchers from the University of Michigan, Johns Hopkins University School of Medicine and the Royal Belgian Institute of Natural Sciences present their findings in the July 25 issue of the Proceedings of the National Academy of Sciences.
Their work focuses on Teilhardina, an ancient genus that resembled the saucer-eyed, modern-day primates known as tarsiers. Like tarsiers, monkeys, apes and humans, Teilhardina was a true primate, or euprimate. In both Asia and Europe, the genus is the oldest known primate; in North America, it appears in the fossil record around the same time as another primate, Cantius. Previously, scientists had come up with four ways to explain the geographic distribution pattern.

The first is that primates originated in Africa and spread across Europe and Greenland to reach North America. Another possibility is that they originated in North America and travelled across a temporary land bridge connecting Siberia and Alaska. A third hypothesis is that primates had their origins in Africa or Asia and traveled through North America to reach western Europe. Finally, it has been suggested that the group originated in Asia and fanned out eastward to North America and westward to Europe.
In the new research, U-M paleontologist Philip Gingerich and coworkers re-evaluated the four hypotheses by comparing with unprecedented precision the times of first appearance of Teilhardina in Asia, Europe, and North America. To achieve such precision, they used a carbon isotope curve recently documented on all three continents. Carbon in the atmosphere, earth and living organisms differs in the proportion of carbon-12 and carbon-13 present. A flood of carbon-12 is associated with the onset of an event known as the Paleocene-Eocene thermal maximum (PETM), one of the most rapid and extreme global warming events recorded in geologic history. It was during the PETM that modern primates first appeared 55 million years ago. Teilhardina in Asia precedes the maximum flood of carbon-12, Teilhardina in Europe coincides with it, and Teilhardina in North America appears just after the maximum. Based on this evidence, the researchers concluded that none of previously proposed scenarios was likely. Instead, they propose that Teilhardina migrated from South Asia to Europe, crossing the Turgai Straits---an ancient seaway between Europe and Asia---and then spread to North America by way of Greenland.
The whole dispersal event happened within about 25,000 years.

"It is remarkable to be able to study evolutionary events so deep in the past with such precision. The speed of dispersal and the speed of evolutionary change during dispersal are near the maximum for such rates observed today, and the rapid change and dispersal were almost certainly driven by profound greenhouse warming at the Palaeocene-Eocene boundary" - Gingerich, who is the Ermine Cowles Case Collegiate Professor of Palaeontology and director of the U-M Museum of Palaeontology.

Source University of Michigan

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Blobrana


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Seeing the Serpent
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The ability to spot venomous snakes may have played a major role in the evolution of monkeys, apes and humans, according to a new hypothesis by Lynne Isbell, professor of anthropology at UC Davis. The work is published in the July issue of the Journal of Human Evolution.

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Blobrana


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RE: Homo Sapiens
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These three shell beads are between 90,000 and 100,000 years old, according to an international research team.



Two of the ancient beads come from Skhul Cave on the slopes of Mount Carmel in Israel. The other comes from the site of Oued Djebbana in Algeria. The marine shells from Skhul are held by the Natural History Museum in London, while the shell bead from Oued Djebbana is held by the Museum of Man in Paris.

The finds, which pre-date other ancient examples by 25,000 years, are described in the US journal Science.

http://www.ucl.ac.uk/media/library/seashellbeads

-- Edited by Blobrana at 19:59, 2006-06-23

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Blobrana


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Fresh analysis of beads made from seashells by a team led by a University College London researcher reveals that modern humans used jewellery at least 25,000 years earlier than previously thought.

Researchers from the UK, France and Israel report in the journal Science that they re-examined beads, originally excavated from a site in Israel and one in Algeria in the early half of the 20th Century, using elemental and chemical analysis. Results show the beads date from between 100,000 to 135,000 years ago – which is much earlier than a recent significant find of beads excavated in South Africa that date from 75,000 years ago.

Personal ornaments, along with art, are generally considered as archaeological proof of an aptitude for symbolic thinking and the findings have major implications for the debates about the origins of behaviourally modern humans.

"Symbolically mediated behaviour has emerged as one of the few unchallenged and universally accepted markers of modernity. A key characteristic of all symbols is that their meaning is assigned by arbitrary, socially constructed conventions and it permits the storage and display of information. The main challenge for paleoanthropology is establishing when in human evolution this ability developed. Archaeological evidence suggests that Anatomically Modern Humans (AMH) from Africa were also behaviourally modern before 40,000 but until now evidence has remained scant.
Given that the same shell species were unearthed at distinct geographical sites suggests that a symbolic tradition extended across the Eastern and Southern Mediterranean. It supports the hypothesis that a widespread tradition of beadwork existed in North Africa and the countries of Western Asia well before the arrival of AMH in Europe" - Dr Marian Vanhaeren, of the AHRC Centre for the Evolutionary Analysis of Cultural Behaviour, University College London Institute of Archaeology, and lead author of the study.

Human remains excavated from Ethiopia demonstrate that Homo sapiens in Africa were anatomically modern 160,000 years ago, but debate continues over when and where humans first became behaviourally modern.

In 2004 engraved ochre and Nassarius kraussianus seashell beads bearing human-made perforations and traces of use were discovered at the Blombos Cave, South Africa and were dated to 75,000 years ago. The finding suggests that humans became behaviourally modern much earlier than previously thought but it has been hotly contested because of a lack of corroborating evidence from other sites.

The seashell beads that have been re-examined were originally unearthed at a Middle Palaeolithic site at Es-Skhul, Mount Carmel, Israel and from the type-site of the Aterian industry, of Oued Djebbana, Bir-el-Ater, Algeria. The shells from Skhul are currently held in the Department of Palaeontology, Natural History Museum (NHM), London, and the specimen from Oued Djebbana in the Department of Prehistory, Musée de l'Homme, Paris.

Remoteness from seashore – up to 200 km in the case of Oued Djebban – and detailed comparison to natural shell assemblages indicates in both cases there was deliberate selection and transportation by humans of Nassarius gibbosulus seashells for symbolic use.

"Personal ornaments have many different – and often multiple – functions. They may be used to beautify the body, function as 'love letters' in courtship, or as amulets that express individual or group identity. The function of the oldest beads in Africa and Eurasia were probably different because in the first case we have only one bead type and in the second a rich variety of types.
We think that the African evidence may point to the beads being used in gift-giving systems which function to strengthen social and economic relationships. The European evidence suggests the beads were used as markers of ethnic, social and personal identity" - Dr Marian Vanhaeren.

Source University College London

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Blobrana


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Posts: 131433
Date:
Neanderthal DNA
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Scientists have recovered DNA from a Neanderthal that lived 100,000 years ago - the oldest human-type DNA so far.

It was extracted from the tooth of a Neanderthal child found in the Scladina cave in the Meuse Basin, Belgium.
The study, reported in Current Biology, suggests our distant cousins were more genetically diverse than once thought.

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Blobrana


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Date:
Neanderthal
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The first sequences of nuclear DNA to be taken from a Neanderthal have been reported at a US science conference at New York's Cold Spring Harbour Laboratory.

Geneticist Svante Paabo and his team say they have managed to sequence around a million base-pairs, which comprises 0.03% of the Neanderthal's entire DNA genome, from a 45,000-year-old male Neanderthal fossil found in Vindija Cave outside Zagreb, Croatia.

It is a significant advance on previous research that has extracted mitochondrial DNA (mtDNA) from Neanderthal (Homo neanderthalensis) specimens.

The work should reveal how closely related the Neanderthal species was to modern humans, Homo sapiens.
It is thought that Neanderthals diverged from the evolutionary line that led to modern humans about 315,000 years ago.

Preliminary analysis of the genome sequence shows the Neanderthals Y chromosome is very different from modern human and chimpanzee Y chromosomes; more so than for the other chromosomes in the genome.
This might suggest that little interbreeding occurred between our own species and the Neanderthals.

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Blobrana


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Date:
Australopithecus anamensis
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Fossils discovered in eastern Ethiopian desert are a missing link between our ape-man ancestors some 3.5 million years ago and more primitive hominids a million years older, according to a new study released on Wednesday.
The fossils are from the most primitive species of Australopithecus, known as Australopithecus anamensis, and date from about 4.1 million years ago, reported researchers from Ethiopia, Japan, France and the United States.
Australopithecus anamensis is intermediate between the two not only chronologically but also in terms of its anatomy.
The findings were published in an April 13 issue of the journal Nature.

More primitive hominids in the genus Ardipithecus date from between 4.4 million and 7 million years ago and were much more ape-like, though they walked on two legs.

"This new discovery closes the gap between the fully blown Australopithecines and earlier forms we call Ardipithecus. We now know where Australopithecus came from before 4 million years ago" - Tim White, lead author of the Nature paper and professor at the University of California, Berkley.

Professor Tim White of the University of California, Berkeley, and colleagues unearthed the cache of fossils in the Middle Awash region of Ethiopia.

Since the first Australopithecus skull was discovered in South Africa 82 years ago, fossils of this hominid have been found all over eastern Africa spanning a 3-million-year time period.
Seven separate species have been named, including the most primitive, Australopithecus anamensis, which dates from 4.2 million years ago, and Australopithecus africanus. The most specialised species, Australopithecus boisei, died out about 1.2 million years ago, long after the more human-like genus Homo had spread throughout the world.

On the other hand, Ardipithecus was discovered by White and his team in 1992. White and his team named the 4. 4 million-year-old fossils Ardipithecus ramidus. But the relationship between Australopithecus and Ardipithecus remained unclear, because of a million-year gap between these two genera.

"The fact anamensis is sandwiched between earlier and later hominids is what is really significant about this Ethiopian sequence" - Tim White.

The new fossil finds, jawbones and teeth from each of two localities, bridge that gap. With Ardipithecus in older rocks and Australopithecus afarensis in overlying rocks, the newly announced fossils are intermediate in time and anatomy.

The fossils represent at least eight individuals and include the largest hominid canine ever found, the earliest known Australopithecus thigh bone as well as hand and foot bones.
The excavation at Asa Issie also uncovered the remains of pigs, monkeys and big cats. The fauna suggest that anamensis was living in a closed, wooded habitat.
The teeth tell a story about the organism's diet. Australopithecus's large cheek teeth allowed it to subsist on a broader diet of tough, fibrous plants. The teeth of Ardipithecus were smaller, restricting it to a diet of softer, less abrasive food.

With its teeth, Australopithecus became a superior omnivore, able to eat tubers and roots with more fibre and grit, adapting it better to times of scarcity during periods of extended drought.

"They may have been small brained, but they stuck around a longtime, fully half of our zoological family's 6-million-year existence on the planet" - Tim White.

The researchers are cautious about claiming that the new fossils are closely related to the most recent member of the genus Ardipithecus, Ardipithecus ramidus, since the two are separated by only 300,000 years. But the fossils show clear descent from the genus Ardipithecus.

The fact that fossils of Ardipithecus ramidus, Australopithecus anamensis and Australopithecus afarensis have been found in successive sediment layers in the same area also indicates an evolutionary sequence.
Australopithecus afarensis was first recognised in the 1970s on the basis of the now famous "Lucy" skeleton from Hadar, Ethiopia, and footprints preserved in volcanic ash at Laetoli, Tanzania.

"It is fair to say that some species of Ardipithecus gave rise to Australopithecus" - Tim White.

One explanation is that one species simply evolved into the other - so-called phyletic evolution.
Another possibility is that Australopithecus first emerged as a side branch of Ardipithecus. Under this scheme the mother species would have lived alongside the daughter species for some period of time before the mother species died out.
But no overlap between any of the three species has been found in Ethiopia.

Tim White, Gen Suwa and Berhane Asfaw discovered the first Ardipithecus ramidus fossils in the 1990s.

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