Some Thoughts On The Uniqueness Of Mankind’s Evolution
Posted 02 March 2008 - 07:28 AM
Posted 08 March 2008 - 09:09 PM
Posted 23 March 2008 - 04:18 PM
There seems to be a general acceptance, among most people, of the "out of africa" hypothesis, that is that early man originated in africa and spread out from there about 50,000 years ago.
This is not a fact but from what evidence we have and from "educated assumptions" it seems, at least for now, to be a viable hypothesis
However it may not be as clear cut as that, it seems there "may" have been an earlier "out of africa" migration, perhaps some 50,000 years before the main one, and modern humans are thought to be more closley related to the second migration
it's likely that some populations native to Israel, Jordan, Lebanon, Syria, Australia, New Zealand and Indonesia retain genetic vestiges of the earlier migrants, according to the Michael Schillaci.
Schillaci, an assistant professor in the Department of Social Sciences at the University of Toronto, also found the earlier group of emigrants had some genetic similarity to Neanderthals, a hominid that left Africa much earlier, settling in Europe and parts of western and central Asia.
"This could be the byproduct of limited [interbreeding] with Neanderthals, or a shared more recent common ancestry with Neanderthals, Humans and Neanderthals share a common Homo ancestor in Africa at around 500,000 years ago. However, Neanderthals evolved in Europe, while modern humans evolved in Africa."
The earliest known individuals from the Near East, he found, were genetically similar to the earliest individuals from Australia, New Zealand and Indonesia. All modern-day humans are more similar to Europeans who lived between 40,000 and 10,000 years ago -- after the second wave from Africa
"The most likely explanation...is that the expansion out of Africa that was ancestral to the early Australasians occurred before the well-accepted expansion at around 50,000 years ago that led to the colonization of Europe," he said, adding that the first populations out of Africa were later "swamped genetically by the subsequent larger expansion."
Based on the findings, which have been accepted for publication in the Journal of Human Evolution, he concludes the first human group to have left Africa "may well have been a separate subspecies" of modern human.
Hopefully one day we will be able to shed the "Racism Fears" that block to our study of human evolution, in that i mean that there is a total abhorrance to any suggestion that different racial groups on our planet may have had different evolutionary paths and/or that different racial groups may have different origins which subsequent interbreeding has covered up
I am a staunch anti rascist but i do not think that being one forces me to have a certain view on human evolution, I have never been 100 % convinced that all races of modern mankind trace back directly to a single common source, it seems that at least some "experts" agree with my thoughts
More on the Neanderthal "Split"
Neanderhals and humans possibly shared a common ancestor, but we may have split from them as long as 400,000 to 350,000 years ago
Dr Springer from the Natural History Museum in London :
"Neanderthal features began to emerge from Homo heidelbergensis just before 500,000 years ago. "Heidelberg Man" was muscular and tall, had a relatively large brain, and usually grew to heights of 6 feet or more. Markings on bones suggest the burly hominid dined on enormous animals, such as mammoths, rhinos and elephants, some of which weighed over 1,500 pounds"
Stringer thinks that since Neanderthals and humans split relatively early, "we may need to designate the earlier part [on the human side] as 'Archaic sapiens.'" That would allow researchers to account for the different types of human fossils that fall between the divergence date and the appearance of more modern-looking people in Africa around 50,000 years ago.
Osbjorn Pearson, an associate professor of anthropology at the University of New Mexico, recently conducted similar research on Neanderthals and humans. He fully agrees with the new findings.
"From their, and other scientists' previous research, it has become clear that many of the physical differences between human skulls are due to random genetic changes that make populations diverge over time," Pearson said.
"It is gratifying -- and, for many anthropologists, perhaps unexpected -- that the bones and genes tell the same story."
"The results also reinforce the conclusion that it is unlikely that Neanderthals...contributed substantially to the modern human gene pool."
Posted 29 March 2008 - 02:31 PM
The researchers said the fossil found last year at Atapuerca in northern Spain, along with stone tools and animal bones, is up to 1.3 million years old. That would be 500,000 years older than remains from a 1997 find that prompted the naming of a new species: Homo antecessor, or Pioneer Man, possibly a common ancestor to Neanderthals and modern humans.
The earliest known human fossils found outside of Africa are from Dmanisi in the modern-day Republic of Georgia. Identified as either Homo erectus or Homo ergaster, the remains date to around 1.8 million years ago.
"The Republic of Georgia is at the gates of Europe," BermÃºdez de Castro said. "It's the crossroads between Africa and Eurasia from a geographical point of view."
But H. erectus fossils estimated to be 1.6 million years old have been located as far away as Java in Indonesia, he noted.
Because of that, "we think that in Europe we are going to find more hominin fossils probably older than those of Sima del Elefante," BermÃºdez de Castro said.
The Spanish-led team adds that the new fossil human likely marks the beginnings of a native European species represented by the younger finds at Atapuerca.
I find this all very interesting..look..I am of mixed race, my son is half spanish half..well.. english ( i am half indian half english romany gypsy), I have English, Indian, Irish, American, Canadian, German, French, South African, Dutch and Iraqi relatives...probably more. So we are a VERY mixed race family. Curiously my father is from the Punjab and my mothers' ancestors, being romany gypsy, originated from the north of India, though there has always been a strong belief that during their travels my mothers ancestors encountered travelling Jews and there was intermarrage. My mother is convinced that we have Jewish blood.
I marched ( and fought on the streets) with Anti Fascist groups in the 80's and was a signed up member of the ANC so I think it is fair to say that I am not racsist..well not in the conventional sense.
I strongly believe that though mankind may have an ancient common ancestor, probably from africa, i think that there have been numerous diversifications since then. Though eurpoeans, africans and asians may have a common distant ancestor i think our early history is even more "interesting" than it seems. Of course i do not deny that all mordern humans are of the same group, homo sapiens sapiens. I do beleive that our evolution is far from mapped out. Something remarkable happened in our early evolution, perhaps we will never find out what that was but I think it is worth having an open mind on the subject especially since, as i have pointed out before, it seems that each year brings new discoveries and previously held beliefs are shown to be just that..beliefs
Posted 30 April 2008 - 01:51 AM
Posted 13 June 2008 - 01:45 PM
Posted 30 June 2008 - 07:01 AM
"Something" incredibly amazing happened around 100-200 thousand years ago at this change over point and I find it interesting that the more we find out about Neanderthal the more we see them as sophisticated and relatively intelligent, for example
Britain's last Neanderthals were more sophisticated than we thought :
Bearing in mind my highly speculative theory that mordern man is the result of active "manipulation" by some "third party" I think the concept of an intelligent Neanderthal is very interesting
"That the sons of God saw the daughters of men that they were fair; and they took them wives of all which they chose" - Genesis 6:2
Of course I am completely wacko and the mainstream anthroplogists have everything worked out..or do they ? What about the "Hobbits" of Flores ?
The "standard" out of Africa view is :
As the gaps are filled, the story is likely to change, but in broad outline, today's scientists believe that from their beginnings in Africa, the modern humans went first to Asia between 80,000 and 60,000 years ago. By 45,000 years ago, or possibly earlier, they had settled Indonesia, Papua New Guinea and Australia. The moderns entered Europe around 40,000 years ago, probably via two routes: from Turkey along the Danube corridor into eastern Europe, and along the Mediterranean coast. By 35,000 years ago, they were firmly established in most of the Old World. The Neanderthals, forced into mountain strongholds in Croatia, the Iberian Peninsula, the Crimea and elsewhere, would become extinct 25,000 years ago. Finally, around 15,000 years ago, humans crossed from Asia to North America and from there to South America
From this we are to assume that it is just a coincidence that a totally seperate evolutionary path led to Neanderthals who :
Made tools, but they worked with chunky flakes struck from large stones. Modern humans' stone tools and weapons usually featured elongated, standardized, finely crafted blades. Both species hunted and killed the same large mammals, including deer, horses, bison and wild cattle. But moderns' sophisticated weaponry, such as throwing spears with a variety of carefully wrought stone, bone and antler tips, made them more successful. And the tools may have kept them relatively safe; fossil evidence shows Neanderthals suffered grievous injuries, such as gorings and bone breaks, probably from hunting at close quarters with short, stone-tipped pikes and stabbing spears. Both species had rituals—Neanderthals buried their dead—and both made ornaments and jewelry
Posted 10 November 2009 - 01:58 PM
Humans were living and thriving on open grassland in Africa as early as 2 million years ago, making stone tools and using them to butcher zebra and other animals. That's according to powerful evidence from artefacts found at Kanjera South, an archaeological site in south-west Kenya.
"There is no clear evidence of any hominin being associated with or foraging in open grassland prior to this 2-million-year-old site," says Thomas Plummer of Queens College at the City University of New York.
All of the other earlier hominins that have been found in the geological record – such as Ardipithecus ramidus and Australopithecus afarensis – known as Ardi and Lucy, respectively - lived either in dense forest or in a mosaic of woodland, shrub and grasses, says Plummer.
The Kanjera South site now offers a glimpse into the lives of our ancestors as they were starting to adapt to life on the plains. "The site occurs in a grassland setting, dominated by grass-eating animals, and is thus the first clear evidence that grasslands were indeed part of the diversity of environments inhabited by early human tool-makers," says team member Richard Potts of the Smithsonian Institution's National Museum of Natural History in Washington DC.
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So Ida's not the "missing link":
Remember the "fossil that will change everything"? When Darwinius masillae, nicknamed Ida, was revealed to the world back in May, an avalanche of PR hype claimed it as a "missing link" in human evolution. This lemur-like creature, the promotional campaign had it, was an ancestor of us all.
Plenty of doubts were raised about this at the time -- including here on this blog -- both about Ida's claim to a place on the human branch of the primate family tree, and the wisdom of producing popular films and books about scientific discoveries that have yet to be published and peer-reviewed. Today has brought a fresh twist.
A second new adapid named Afradapis longicristatus, closely related to Darwinius, is described in Nature by a team led by Erik Seiffert, of Stony Brook University in New York state. And analysis of the two fossils indicates strongly that neither is an anthropoid. Both Darwinius and Afradapis appear to be members of a group more closely related to lemurs and lorises than to monkeys, apes and people, which has left no known modern descendents. The scenario advanced to promote Ida as "the Link" appears to be wrong.
Did Modern man had sex with Neanderthals ? Or Could there have been genetic mixing of some kind ?
Modern man and Neanderthals had sex across the species barrier, according to leading geneticist Professor Svante Paabo
Professor Paabo, who is director of genetics at the renowned Max Planck Institution for Evolutionary Anthropology in Leipzig, made the claim at a conference in the Cold Springs Laboratory in New York.
But Prof Paabo said he was unclear if the couplings had led to children, of if they were capable of producing offspring.
"What I'm really interested in is, did we have children back then and did those children contribute to our variation today?" he said in an article in The Sunday Times.
"I'm sure that they had sex, but did it give offspring that contributed to us? We will be able to answer quite vigorously with the new [Neanderthal genome] sequence."
The phenomenon is already seen in modern animals such as horses and zebras, and lions and tigers, but resulting offspring have always been infertile.
In recent years, fossils with both Neanderthal and modern human features have been found suggesting the two species interbred but previous scans of Neanderthal genes reveal Neanderthal DNA to have a very different make-up to modern man's.
It is hoped the new claim will provide an answer to these conflicting discoveries.
Neanderthals were primitive beings that lived alongside modern man 30,000 years ago. The two species coexisted for 10,000- 12,000 years before Neanderthals eventually died out.
Prof Paabo is seeking to prove his theory by examining Neanderthal fossils for traces of modern man's DNA. But if Neanderthal DNA existed in modern man's genes, he believes it will have been diluted below detectable levels.
His findings will be published in his analysis of the Neanderthal genome shortly
Posted 13 January 2010 - 08:56 PM
Charles Darwin's On the Origin of Species, published 150 years ago Tuesday, opened the book on our evolutionary past, which has since been traced by scientists back to fossil apes.
But where is evolution taking us? Will our descendants hurtle through space as relatively unchanged as the humans on the starship Enterprise? Will they be muscle-bound cyborgs? Or will they chose to digitize their consciousnesses—becoming electronic immortals?
And as odd as the possibilities may seem, it's worth remembering that, 150 years ago, the ape-to-human scenario in On the Origin of Species struck many as nothing so much as monkey business
Posted 13 April 2010 - 03:37 AM
The new species of hominid, the evolutionary branch of primates that includes humans, is to be revealed when the two-million-year-old skeleton of a child is unveiled this week.
Scientists believe the almost-complete fossilised skeleton belonged to a previously-unknown type of early human ancestor that may have been a intermediate stage as ape-men evolved into the first species of advanced humans, Homo habilis
I should add a "MAY have been found" to that !!
Posted 13 April 2010 - 03:40 AM
Posted 24 April 2010 - 11:08 PM
An examination of the DNA of 1,983 people from around the globe suggests that extinct human species such as Homo neanderthalensis or Homo heidelbergensis interbred with our own ancestors during two separate periods, and their genes remain in our DNA today. The research was carried out by a group of genetic anthropologists from the University of New Mexico, and leader of the team, Jeffrey Long, said the findings mean Neanderthals did not completely disappear, but “there is a little bit of Neanderthal left over in almost all humans
Posted 21 June 2010 - 11:08 PM
ScienceDaily (June 6, 2010) — Scientists at the Genome Institute of Singapore (GIS), a biomedical research institute of the Agency for Science, Technology and Research (A*STAR), and their colleagues from the National University of Singapore, Nanyang Technological University, Duke-NUS Graduate Medical School and Princeton University have recently discovered that viruses that ‘invaded’ the human genome millions of years ago have changed the way genes get turned on and off in human embryonic stem (ES) cells.
Posted 27 June 2010 - 03:49 PM
An older guy has sauntered into Lucy’s life, and some researchers believe he stands ready to recast much of what scientists know about the celebrated early hominid and her species.
Excavations in Ethiopia’s Afar region have uncovered a 3.6-million-year-old partial male skeleton of the species Australopithecus afarensis. This is the first time since the excavation of Lucy in 1974 that paleoanthropologists have turned up more than isolated pieces of an adult from the species, which lived in East Africa from about 4 million to 3 million years ago.
Posted 27 June 2010 - 03:54 PM
A doctoral thesis conducted at the National Center for Research on Human Evolution (Centro Nacional de Investigación sobre la Evolución Humana) -associated with the University of Granada-, analysed the teeth of almost all species of hominids that have existed during the past 4 million years. Quantitative methods were employed and they managed to identify Neanderthal features in ancient European populations.
The main purpose of this research whose author is Aida Gómez Robles- was to reconstruct the history of evolution of Human species using the information provided by the teeth, which are the most numerous and best preserved remains of the fossil record. To this purpose, a large sample of dental fossils from different sites in Africa, Asia and Europe was analysed. The morphological differences of each dental class was assessed and the ability of each tooth to identify the species to which its owner belonged was analysed.
The researcher concluded that it is possible to correctly determine the species to which an isolated tooth belonged with a success rate ranging from 60% to 80%. Although these values are not very high, they increase as different dental classes from the same individual are added. That means that if several teeth from the same individual are analysed, the probability of correctly identifying the species can reach 100%.
Aida Gómez Robles explains that, from all the species of hominids currently known "none of them has a probability higher than 5% to be the common ancestor of Neardenthals and Homo sapiens. Therefore, the common ancestor of this lineage is likely to have not been discovered yet".
Posted 17 July 2010 - 10:07 PM
It indicates that apes and Old World monkeys diverged millions of years later than previously thought, say the scientists.
The discovery was made in Saudi Arabia by researchers from the University of Michigan.
They described the primate, Saadanius hijazensis, in the journal Nature.
Dr William Sanders from the University of Michigan, who led the research, said this was "an extraordinary find".
The skull of this previously unknown species had some features that are shared by Old World monkeys and apes, including humans, today
"Saadanius is close to a group that eventually led to us," said Dr Sanders.
Posted 15 August 2010 - 05:39 AM
That pushes back the earliest known tool use and meat-eating in such hominins by more than 800,000 years.
Bones found in Ethiopia show cuts from stone and indications that the bones were forcibly broken to remove marrow
Posted 15 August 2010 - 05:40 AM
ScienceDaily (Aug. 11, 2010) — By deciphering the genetics in humans and fish, scientists now believe that the neck -- that little body part between your head and shoulders -- gave humans so much freedom of movement that it played a surprising and major role in the evolution of the human brain, according to New York University and Cornell University neuroscientists in the online journal Nature Communications (July 27, 2010.)
Posted 21 August 2010 - 06:57 PM
Rice University researchers have conducted what they describe as the most "robust" statistical comparison of 10 human genetic models to confirm the age of the maternal ancestor of all living humans.
"Mitochondrial Eve," as she is called, lived about 200,000 years ago - probably somewhere in Africa, according to Marek Kimmel, professor of statistics at Rice and co-author of a study in the journal Theoretical Population Biology. The existence of a common maternal ancestor was first discovered in 1987.
"These are modern humans," Kimmel said in an interview with CBSNews.com. "They go back 200,000 years but physically, they are modern. Regarding their brains, the brain case is the same as ours and the superficial appearance of their brains, judging from the imprint on their skulls, is similar to ours."
The research was carried out using mitochondrial genomes to measure modern humans' genetic links back to "Mitochondrial Eve" because mitochondria are inherited only through females. This makes any examination of inheritance patterns much simpler - which is why it's commonly used. (The male counterpart would be the "Y" chromosome.)
Posted 01 November 2010 - 11:36 AM
An international team of researchers, including a physical anthropology professor at Washington University in St. Louis, has discovered well-dated human fossils in southern China that markedly change anthropologists perceptions of the emergence of modern humans in the eastern Old World
The discovery of early modern human fossil remains in the Zhirendong (Zhiren Cave) in south China that are at least 100,000 years old provides the earliest evidence for the emergence of modern humans in eastern Asia, at least 60,000 years older than the previously known modern humans in the region.
“These fossils are helping to redefine our perceptions of modern
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