Posted on this earlier, but its import was not
as clear. What is now strongly indicated
is that there has been a human primate linage going on for at least two million
years on a ‘global basis’. That would
obviously exclude the Americas but assures us that gene mixing was ongoing throughout
Eurasia and Africa.
We can presume hunting
skill simply using the ability to hurl stones accurately at your local water
hole. This could take down a lion and we
have evidence of this behavior in Africa.
I have seen a report of the Sasquatch doing just this and its brain case
is also small.
The actual advantage
provided by been upright and having an excellent throwing arm have been severely
underestimated. I will go one better
here. Many animals can be stalked by an
upright individual in plain sight by simply remaining still when the target is
looking at you. This is good enough to
approach a wood to chuck within fifty yards or less over clear ground. Add marginal cover and it gets easier.
My point is that a lot
of the potential game animals have terrible eyesight and can be easily stalked
with a modicum of skill.
Skull find in Georgia
provides new evidence about early human evolution
IVAN SEMENIUK - SCIENCE
REPORTER
The
Globe and Mail
Published Thursday,
Oct. 17 2013,
Globalization
has a new face – and it is a rather long one.
Researchers
working in the foothills of the Caucasus mountains in the Republic of Georgia
have unveiled a fossil they say could shift thinking on the earliest chapters
of the human story.
The
1.8-million-year-old adult skull is the best preserved example yet of a hominid
species that once roamed the forests and plains of western Asia – the first
members of the genus Homo, which includes modern humans, to wander out of
Africa.
But
with its small brain case, long face, large teeth and massive jaw, the
creature also presents scientists with a puzzle.[
this creature certainly did not use fire and relied on its jaws to process
plant material and likely meat. At this
point it could likely use a weapon - Arclein]
“This
is a strange combination of features that we didn’t know before in early Homo,”
said Marcia Ponce de León, a researcher at the Anthropological Institute and
Museum in Zurich, Switzerland, and co-author of the research published on
Friday in the journal Science.
Dr.
Ponce de León and her colleagues took nearly eight years to prepare and study
the skull, which was unearthed in 2005 at the Dmanisi excavation site, about 60
kilometres southwest of the capital, Tbilisi. Scientists were ecstatic when it
matched a lower jawbone found a short distance away five years earlier, a case
of “extreme fortune,” Dr. Ponce de León said.
The
skull’s bulky features mean that it was likely male. It has a healed fracture
on one cheek, perhaps the result of an injury sustained in conflict with
another individual, researchers say, or battling with predators over an animal
carcass, a key food source for hominids that lived in the region.
Because
it shares traits with at least two early species, Homo habilis and Homo
erectus, the find puts a new spin on the debate over whether the species
distinctions are as real as previously thought. The authors argue that both
species, along with a third, Homo rudolfensis, discovered in Kenya in 1972,
are part of a continuous population that once stretched from Africa to
Southeast Asia.
“We
have, now, one global human species,” Christoph Zollikofer, also with the
Zurich museum, said of present-day humans. “What we can infer from our studies
at Dmanisi is that, 1.8 million years ago, there was another single, global
species” that included all the early varieties of Homo.
The
authors base their case not just on the newly described skull but on the way it
relates to four less-complete ones from Dmanisi. Because the site was abruptly
buried in ash from a volcanic eruption, all the skulls are thought to be from
the same general time and location. That implies the differences in their
features are the result of individual variation rather than species differences.
The authors argue that the differences that distinguish what are now
considered separate species of early Homofound in other locations fall
within the range of variation seen among the individuals at Dmanisi.
Other
scientists have called the new find spectacular even if they do not agree with
the authors’ interpretation, noting that similar-looking species of hominids
could have exhibited significantly different behaviour.
“Seen
across a parking lot, a Mercedes and a Chrysler might look pretty similar, but
there’s a hell of a lot going on inside that suggest these are very different
motor cars,” said Bernard Wood, a paleoanthropologist at George Washington
University, who is skeptical of the one-species theory.
Yet
the new find adds to an increasingly nuanced picture of early Homo that
may have included “back-migration” from Asia as well as outward migration from
Africa. How this story connects to modern humans remains unclear. Gaps in the
fossil record mean that researchers are not sure whether Homo erectus,
including the Dmanisi hominids, was an ancestral species to Homo sapiens or
an offshoot that was later supplanted by a separate African line.
What
the Dmanisi finds do show is that early Homo “did not need a large brain or sophisticated stone tools to disperse out
of Africa,” said lead author David Lordkipanidze of the Georgian National
Museum in Tbilisi.
Susan
Antón, a professor of anthropology at New York University, who was not involved
with the find, agrees that the need to adapt to new environments and challenges
required by such a large-scale migration means that the hominids of that period
were not just evolving biologically, but exhibiting a behavioural
flexibility that would later become the precursor to culture.
“They’ve
pushed that part of being human back much, much earlier,” Prof. Antón said.
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