Saturday, December 01, 2012

CHAD FOSSILS (3.5 MILLION YEARS OLD) FOUND BUT FARTHER WEST THAN ANY OTHER ANCIIENT BONES SO CALLED A NEW SPECIES

In 1993, researchers in Chad unearthed a 3.5-million-year-old hominid lower jaw
fragment and a few attached teeth. Based on the fossils' age, many anthropologists think the bones belonged to Australopithecus afarensis. But the specimen was found more than 2,400 kilometers farther west than any other afarensis bones, and subtle differences in the size and shape of the fossils led the discoverers to conclude they had found a new species. They named it Australopithecus bahrelghazali after the Bahr el Ghazal valley where the bones were recovered. Since then, researchers haven't found any other bahrelghazali fossils, and its species' status remains controversial.

With just a jaw and teeth, there's not too much scientists can say about what Australopithecus bahrelghazali looked like or how it lived its life, but
analyzing the teeth's chemistry is one way to assess what the species ate.

Julia Lee-Thorp of Oxford University and colleagues have revealed that Australopithecus bahrelghazali mainly ate plants - probably grasses and sedges -and like modern baboons that live on savannahs, probably different parts of these plants, including underground tubers and bulbs. Based on the other types of animals found near the hominid, the researchers say bahrelghazali made its home in an open grassland, with few trees, near a lake.

The results mean that by 3.5 million years ago hominids were probably already capable of eating a variety of foods depending on what was locally available. Being a food generalist may have allowed Australopithecus bahrelghazali to explore new environments and leave behind the forests in which earlier hominids and their ancestors had resided.

Edited from ScienceNews (12 November 2012), Smithsonian.com (14 November 2012)
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STONE TIPPED SPEARS DATED TO 1/ 2MILLLION YEARS AGO -- 200,000 EARLIER THAN PREVIOUSLY THOUGHT

Our ancestors were hunting with stone-tipped spears around 200,000 years earlier than previously thought - meaning the technology must have been developed by Homo heidelbergensis,(sometimes called archaic homo sapiens.

The use of spears for hunting has been dated back to at least 600,000 years ago from sites in Germany, but the oldest spears are nothing more than sharpened sticks. The evidence for stone-tipped spears until now has been no more than 300,000 years old, from triangular stone tips found all over Africa, Europe and western Asia. "They're associated in Europe and Asia with Neanderthals and in Africa with humans and our nearest ancestors," said Jayne Wilkins, an archaeologist at the University of Toronto who took part in the latest research.

To find out if any stone tips were being used on spears any earlier than that, Wilkins examined sharp stones found at a site called Kathu Pan, in the Northern Cape region of South Africa. The sediments in which these tips had been found had been previously dated to 500,000 years old.

Wilkins put the stones under a microscope to look for the tell-tale damage caused when they are used on spears. "We know from experimental studies that when a point is used as a spear tip, the concentration of damage is greater at the tip of the point than along the edges," she said. "That's the same pattern we saw in the Kathu Pan point."

Edited from EurekAlert, and The Guardian (15 November 2012)
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ICE AGE SETTLERS OF SICILY USED A LAND BRIDGE

Early settlers migrated to Sicily during the last Ice Age.

The analysis of human skeletal remains found in the Grotta d'Oriente Cave on the
island of Favignana (Italy), show that modern humans first settled in Sicily
from mainland Italy during the last Ice Age, and that, although they were island
dwellers, consumed little seafood, subsisting mostly on terrestrial food
sources.
The study, led by Marcello Mannino of the Max Planck Institute for
Evolutionary Anthropology, revealed results from a combination of tests and
analyses using mitochondrial DNA data, AMS radiocarbon dating, and isotopic
analysis on skeletal finds and associated remains of human skeletons,
particularly that of skeletal specimen 'Oriente B', unearthed in the cave during
archaeological campaigns in 1972 and 2005.
The analysis revealed the time when humans reached the islands of Favignana
and Levanzo near western Sicily. These islands were connected to mainland Sicily
until the first few millennia of the Holocene Epoch, a geological epoch which
began around 12,000 radiocarbon years ago, when sea levels were low as a result
of the Glacial Maxima of the last Ice Age.
Said Mannino, "The definitive peopling of Sicily by modern humans only
occurred at the peak of the last Ice Age, around 19,000 -26,500 years ago, when
sea levels were low enough to expose a land bridge between the island and the
Italian peninsula". Dating and morphological examination of the skeletal remains
confirmed that the early settlers were modern humans.
The study results also showed that these settlers were not fishermen,
despite their island environment. They subsisted on terrestrial animals rather
than marine sources for meat. Moreover, according to their analysis, this
hunter-gatherer lifestyle likely persisted even as sea levels rose during the
time of their occupation of the island environment.

Edited from Popular Archaeology (27 November 2012), ScienceDaily (28 November
2012)
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