Fossil Cousins didn't make it
- Page 1 - Last update 5/14/2013
Fossil Cousins is for information about other primates living at the time but are not thought to be in the Homo line of descent.
-- 55 myr: New Fossils Push Primate Evolution Back Millions of Years - 6/07/13
-- 12 myr: Genetic Study Suggests Chimps & Humans Split Earlier Than Thought - 6/17/14
-- 12 myr: New Hominid 12 Million Years Old - 6/02/09 - 12 Myr
-- 11 myr: Scientists have discovered a new eleven-million-year-old primate - 11 Myr
-- 7.0 myr: Sahelanthropus tchadensis - 6-7 myr
-- 4.4 myr: Ardi, a 4.4 Million-Year-Old Fossil is Oldest Human Ancestor - 4.4 Myr
-- 3.6 myr: Australopithecus bahrelghazali
-- 3.3 myr: Australopithecus afarensis baby - 3.3 Myr
-- 3.2 myr: Australopithecus afarensis - Lucy - 3.2 myr
-- 2.5 myr: Paranthropus robustus - 1 Myr - 2.5 Myr (Also called Australopithicus Robustus)
Fossils Push Primate Evolution Back Millions of Years
BEIJING, CHINA—Palaeontologists Christopher Beard of Pittsburgh’s Carnegie Museum of Natural History and Xijun Ni of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing spent ten years studying the well-preserved fossils of a tiny creature named Archicebus achilles, thought to be an early ancestor of tarsiers, small tree-dwelling primates. The fossils are at least 55 million years old, suggesting that tarsiers had split from anthropoid primates, which gave rise to monkeys, apes, and humans, at least that long ago. Archicebus achilles has a skull, teeth, and limb bones that resemble those of tarsiers, but its heel and feet bones resemble those of anthropoids. “This mosaic of features hasn’t been seen before in any living or fossil primate,” Beard said.
Tuesday, June 17, 2014
OXFORD, ENGLAND—A new study of the rate of gene mutations in three generations of western chimpanzees agrees with recent findings that the human mutation rate is half as fast as had been previously thought. This new understanding pushes back the most recent common ancestor of humans and chimps to at least 12 million years ago. “Our results add substance to the idea that the human-chimpanzee split was considerably older than has been recently thought,” geneticist Gil McVean of the Wellcome Trust Center for Human Genetics told Live Science.
This should mean that from human ancestry to today we have worked our way thru 12 million years and about two dozen previous hominid species to get here. Scientist speak of animals such as the triceratops that decided it needed huge horns and a rotating ball joint for its skull so it built one. Another animal decided it needed a better weapon to defend against good’ol Rex, decided to grow a huge spiked ball on the end of it tail. Others decided to be quicker and so forth.
If science is right then why didn’t the chimp or the gorilla learn to speak, and develop bipedal upright walking so they could develop like our ancestors? They can’t even properly handle a simple club.
Sometimes I think many of these scientists are just
full of themselves.]
For all who believe in the literal reading of the Christian Bible, the
passage "one day is with the Lord as a thousand years, and a thousand years
as one day" 2 Peter 3:8), is my basis to believe that even though God made
all living things on earth (In 7 days per the text) there is no fixed human
time for 7 of God's days,
since God is eternity, the passage might just as well have read "a million years or even a billion". Therefore, the Bible provides reason why both the Bible and the geologist are correct.
As an example, for 400 years (1604-1611) we were taught; in the truest sincerity, the story of Moses parting the "RED SEA" - it turns out that this was translated from the Greek which was translated from Hebrew, but a re-translation of the original Hebrew gives a corrected translation of "REED SEA". The Reed Sea is/was a tidal marsh near the Mouth of the Nile, and when the tide is out it can be walked across. Pharaoh's forces were probably crossing when the tide came in and Moses no doubt knew this all along, setting a trap for Pharaoh's troops. There is no description of Moses - no one knows his actual likeness.
On the other hand, there is much controversy concerning the translation of Yum Suph (even the word Yum is also spelled Yam). In any case there is no consensus on the translation and there is also much controversy on the location of the nearby cities, so that tracing the exodus route has been and will probably remain an unknown. It is possible that in the final analysis it will be Red Sea. It is the curse of science to render the physical understandable to our inadequate human minds. Even scientist tend to render themselves inadequate when pride and ego is involved.
- This place will fill your brain.
http://www.revealingthelink.com/who-is-ida/from-ida-to-us - If that is not enough try here. List from (Darwinius Masillae) Ida to us. The oldest known primate ever found it is 45 million years old, found in Germany, even the imprint of the skin was preserved.
Hominid 12 Million Years Old Found In Spain, With 'Modern' Facial Features
Date:June 2, 2009
Source:Barcelona, Universitat Autònoma de
Researchers have discovered a fossilized face and jaw from a previously unknown hominoid primate genus in Spain dating to the Middle Miocene era, roughly 12 million years ago. Nicknamed "Lluc," the male bears a strikingly "modern" facial appearance with a flat face, rather than a protruding one. The finding sheds important new light on the evolutionary development of hominids, including orangutans, chimpanzees, bonobos, gorillas and humans.
In a study appearing in the Proceedings of the National Academy of Sciences, Salvador Moyà-Solà, director of the Institut Català de Paleontologia (ICP) at the Universitat Autònoma de Barcelona, and colleagues present evidence for the new genus and species, dubbed Anoiapithecus brevirostris. The scientific name is derived from the region where the fossil was found (l’Anoia) and also from its "modern" facial morphology, characterized by a very short face.
The research team at the ICP also includes collaborator David M. Alba, predoctoral researcher Sergio Almécija, postdoctoral researcher Isaac Casanovas, researcher Meike Köhler, postdoctoral researcher Soledad De Esteban, collaborator Josep M. Robles, curator Jordi Galindo, and predoctoral researcher Josep Fortuny.
Their findings are based on a partial cranium that preserves most of the face and the associated mandible. The cranium was unearthed in 2004 in the fossil-rich area of Abocador de Can Mata (els Hostalets de Pierola, l’Anoia, Barcelona), where remains of other fossilized hominid species have been found. Preparing the fossil for study was a complicated process, due to the fragility of the remains. But once the material was available for analysis, the results were surprising: The specimen (IPS43000) combined a set of features that, until now, had never been found in the fossil record.
Anoiapithecus displays a very modern facial morphology, with a muzzle prognathism (i.e., protrusion of the jaw) so reduced that, within the family Hominidae, scientists can only find comparable values within the genus Homo, whereas the remaining great apes are notoriously more prognathic (i.e., having jaws that project forward markedly). The extraordinary resemblance does not indicate that Anoiapithecus has any relationship with Homo, the researchers note. However, the similarity might be a case of evolutionary convergence, where two species evolving separately share common features.
Lluc's discovery may also hold an important clue to the geographical origin of the hominid family. Some scientists have suspected that a group of primitive hominoids known as kenyapithecines (recorded from the Middle Miocene of Africa and Eurasia) might have been the ancestral group that all hominids came from. The detailed morphological study of the cranial remains of Lluc showed that, together with the modern anatomical features of hominids (e.g., nasal aperture wide at the base, high zygomatic rood, deep palate), it displays a set of primitive features, such as thick dental enamel, teeth with globulous cusps, very robust mandible and very procumbent premaxilla. These features characterize a group of primitive hominoids from the African Middle Miocene, known as afropithecids.
Interestingly, in addition to having a mixture of hominid and primitive afropithecid features, Lluc displays other characteristics, such as a very anterior position of the zygomatic, a very strong mandibular torus and, especially, a very reduced maxillary sinus. These are features shared with kenyapithecines believed to have dispersed outside the African continent and colonized the Mediterranean region, by about 15 million years ago.
In other words, the researchers speculate, hominids might have originally radiated in Eurasia from kenyapithecine ancestors of African origin. Later on, the ancestors of African great apes and humans would have dispersed again into Africa -- the so-called "into Africa" theory, which remains controversial. However, the authors do not completely rule out the possibility that pongines (orangutans and related forms) and hominines (African apes and humans) separately evolved in Eurasia and Africa, respectively, from different kenyapithecine ancestors.
The project at els Hostalets de Pierola is continuing and, the researchers anticipate, more fossil remains will be found in the future that will provide key information to test their hypotheses.
From the evidence gathered by palaeontologists and archaeologists, it
appears that the Australopithecus genus evolved in eastern Africa around
4 million years ago before
spreading throughout the continent. Years ago, during
this time period a number of australopith species emerged, including
Australopithecus afarensis, A. africanus, A. anamensis, A. bahrelghazali,
A. garhi and A. sediba.
There is still some debate amongst academics whether certain African hominid species of this time, such as A. robustus and A. boisei, constitute members of the same genus; if so, they would be considered to be robust australopiths while the others would be considered gracile australopiths.
However, if the Robustus species do indeed constitute their own genus, then they may be given the new name of Paranthropus.
Paranthropus robustus lived in the Cradle of mankind from about 2.5-million to 1-million years ago. It had huge jaws for chewing tough vegetation like roots and tubers. It was not a direct ancestor of mankind, but an ancient cousin.
Fossils of the same Paranthropus genus, but of several species other than robustus, have been
discovered in East Africa since Broom’s groundbreaking find. Paranthropus aethiopicus, discovered and named by Camille Arambourg and Yves Coppens in 1967, lived in the Omo Valley of Ethiopia 2.5-million years ago. The first specimen of another species, Paranthropus boisei, was found by Mary Leakey in 1959 at Olduvai Gorge in Tanzania. Additional Paranthropus boisei fossils have been found in Peninj, Tanzania, and at Chesowanja and Lake Turkana in Kenya. Paranthropus was well adapted to a specialized, mainly vegetarian, diet. As environmental conditions changed it therefore may have been unable to adapt to changes in the available food.
It is widely held by archaeologists and palaeontologists that the australopiths played a significant part in human evolution, and it was one of the australopith species that eventually evolved into the Homo genus in Africa around 2 million years ago, which contained within it species like Homo habilis, H. ergaster and eventually the modern human species, H. sapiens sapiens.
Described as the skull of an Australopithecus afarensis baby, this measures
about 12 cm (5 inches) from the bottom of the chin to the top of the head
(Courtesy Zeresenay Alemseged; © Authority for Research and Conservation of Cultural Heritages).
Pologist Zeresenay Alemseged, who led the scientific team credited with the discovery.
The find revived memories of “Lucy,” believed to be a female in her mid-20s and hailed, when discovered, as the most
complete known skeleton of a pre-human hominid. A hominid is a species on the human branch of the evolutionary tree.
The new specimen, dubbed “Lucy’s baby” by some—though it’s actually thought to have lived a bit earlier than Lucy—is likewise causing a stir over its splendid condition.
That, scientists say, makes it a treasure trove of additional clues to human origins.
Years ago, Lucy, in many researchers’ view, overturned a widespread assumption: that our ancestors evolved intelligence first and upright walking later. She was seen to refute that because her bones suggested at least some upright-walking ability, yet a small, ape-like brain.
This helped revive a notion proposed by Charles Darwin: that upright movement spurred brain evolution by freeing hands for tool use. Henceforth, success in the battle for survival would depend on ever-better tool use, and the brains to enable it.
Like Lucy, the newfound child shows the marks of a species able to walk upright, researchers said; it also offers more clues to the evolution of that skill, and of the brain and speech. It’s a “mine of information about a crucial stage in human evolutionary history,” wrote paleobiologist Bernard Wood of George Washington University in Washington, D.C., in a commentary in the Sept. 21 issue of the research journal Nature.
The scientists credited with the find described it in another paper in the same issue. They estimated that the infant died at age three, possibly in a flood that also buried it in pebbles and sand, helping preserve it.
Artist's conception of a mother and child Australopithecus afarensis. Adult females of the species were some 3½ feet tall, judging from the "Lucy" specimen.
Lucy and the baby, which date to slightly more than three million years ago, are far from the oldest known members of the human family.
That distinction belongs to the chimp-sized Sahelanthropus tchadensis or “Toumai Man,” estimated as seven million years old and found in Central Africa four years ago.
But Lucy and the tot—said to represent a later species, Australopithecus afarensis—would be part of a burst of hominid diversity noted in the fossil record from four to two million years ago.
This is thought to reflect some of the rich evolutionary experimentation that nature tossed up on the way to producing our species, Homo sapiens. Hominids of that period are collectively called Australopiths. Which lineage led to us is unknown, though.
The newfound bundle of bones, found like Lucy in the Ethiopian desert, was also a female, and lived about 3.3 million years ago, its discoverers said. Lucy is thought to have lived 3.2 million years ago.
“The most impressive difference between them is that this baby has a face,” said team leader Zeresenay (Ethiopians’ first names are their formal names.) This face gave away the species, added Zeresenay, of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Also unlike Lucy—nicknamed after a Beatles song—the baby has fingers, a foot and a torso. Tooth structures clued researchers in to its rough age and its sex, they said, while the sediments that had trapped it revealed its time period.
Australopiths in Eastern Africa fight off hyenas over a chunk of meat in an image by paleo-artist Stefano Ricci (Courtesy S. Ricci and Archaeological Museum of Camaiore).
The tot helps explain how A. afarensis blurred ape-human boundaries, Zeresenay said: her shoulder blades resemble a young gorilla’s, suggesting she could climb trees, but her thigh bone is angled like humans’, implying good upright walking ability.
Members of the species seem to have been foraging, upright walkers, capable of “climbing trees when necessary, especially when they were little,” he said.
Zeresenay first led a band of fossil hunters into Ethiopia’s Dikika region in 1999, researchers recounted. Punishing heat, flash floods, malaria, wild beasts and occasional shootouts between rival ethnic groups plague the zone.
On a shadeless December day the next year, the scientists recalled, they hunted under a pounding sun for the prize that had eluded them—our ape-like forebears. Team member Tilahun Gebreselassie then spotted the tot’s face, no bigger than a monkey’s, peering out from a dusty slope.
Tucked beneath it in hard sandstone were more bones, the whole bundle of them no bigger than a canteloupe, one finger still curled in a tiny grasp, researchers said. Zeresenay found a rare example of a hyoid bone, a throat structure later crucial to human speech, he said. This offers a glimpse of the evolution of the voice box, which under some theories is interwoven with that of speech.
Zeresenay spent the next five years scratching away rock from the skeleton with a dentist’s drill, according to members of his team.
What killed the baby is unclear. But it seems the ancient Awash River rapidly buried the body in a flood, the scientists said, preserving rare details such as a full set of both milk teeth and unerupted adult teeth. The brain cast will help reveal “whether our earliest ancestors grew their brains in the uniquely human way,” said a member of the research group, Fred Spoor of University College London.
One of her humanlike knees was complete with a kneecap no bigger than a dried pea, researchers said. But her upper body, like Lucy’s, had many apelike features: small brain, nose flat like a chimp’s, face projecting forward. Her two complete shoulder blades are the first found from an Australopith, Zeresenay said; analyzing their function “will be among the exciting challenges that we will face.”
"Lucy's Baby" a Born Climber, Hinting Human Ancestors Lingered in Trees
Australopithecus afarensis' shoulders pointed upward, new fossil study suggests.
Published October 26, 2012 James Owen for National Geographic News
What made us human? Part of the answer may rest on the shoulders of a 3.3-million-year-old toddler.
Like "Lucy," the fossil child was a member of the species Australopithecus afarensis, pioneers of upright walking. Yet her apelike shoulder blades hint that our forebears may have taken longer than we thought to fully come down to earth, a new study says.
Figuring out when the tree-to-ground transition took place is immensely important to understanding how we became who we are. Bipedalism, after all, gave prehumans a literal head's-up on approaching predators and freed up hands for stone tools, which in turn gave access to more types of food, including brain-boosting animal proteins—among other advantages.
The tiny fossils—including the only known complete A. afarensis scapula, or shoulder blade—add to evidence that that giant stride was more a series of faltering steps.
"What we're showing is that bipedalism wasn't this sudden change that took shape in an early common ancestor," said study co-author David Green, an anatomy professor at Midwestern University in Downers Grove, Illinois.
"As bipedalism was developing, there were other forms of locomotion that were still important."
Clinging to the Branches of the Human Family Tree?
"Selam," or "Lucy's baby," or "Dikika baby"—as the A. afarensis three-year-old has been variously nicknamed—spent millions of years encased in rock in Ethiopia's Dikika region, where the shady forests she knew have long since given way to desert.
After discovering Selam in 2000, Zeresenay Alemseged spent 11 years flecking away sandstone to free what remained of her bones. For the new study, the California Academy of Sciences anthropologist and colleagues compared her fossils with those of living apes, humans, and other early human species.
The team found that the sockets of Selam's shoulder joints point upward, as they do in apes. Likewise, the bony ridge that runs along her shoulder blades is set at a similar angle as in chimpanzees.
These apelike shoulders, along with previously recognized climbing-friendly features, would have allowed Australopithecus species to do a number of things better than humans: raising their arms above their heads, hanging from branches, plucking fruit, and hoisting their bodies into trees.
"The fact that they still maintained the gorilla-like scapula, the long and curved fingers, the short clavicles [collarbones], and a torso which would probably have been funnel shaped, is testament to the presence of an arboreal lifestyle in addition to being fully bipedal," said Alemseged, a National Geographic Society emerging explorer. (National Geographic News is part of the Society.)
In other words—whereas humans can climb trees, if we put our minds to it—A. afarensis was likely truly at ease in the trees and on the ground, according to the study, published Friday in the journal Science.
Case closed? Not quite.
A Puzzle Piece, but What's the Big Picture?
According to University of Missouri paleoanthropologist Carol Ward, the study "provides more evidence of the primitive nature of these animals, so that's really exciting, and it's a key piece of the puzzle."
Ward agreed that the shoulder development of the growing A. afarensis "doesn't seem particularly humanlike." But, she added, "it's hard to know exactly what that means."
Some of the shoulder measurements of adult australopithecines in the study, she said, seem similar to those for human species, especially Neanderthals. And "Neanderthals are very clearly not climbing trees."
Study co-author Green conceded that one adult Australopithecus specimen from Ethiopia has a shoulder blade ridge with an apparently more horizontal, humanlike angle. But, he countered, two Australopithecus shoulder bones from South Africa "are even more apelike than afarensis'."
"Great Fossil" but No Smoking Gun
Scott Simpson, a paleoanthropologist at Case Western Reserve University in Cleveland, said Selam is "a great fossil."
"But," he added, "I don't think it's the smoking piece of information that says these guys were climbing trees."
The "transition to bipedality caused a complete reorganization of the body," altering the pelvis, various knee and ankle bones, the spine, and the foot, he said. But this new analysis "hinges on a very narrow part of the musculoskeletal system."
If the study had taken in the whole skeleton, he said, "I think we would learn a lot more about what's going on."
Green, the study co-author, responded that shoulder blades "have been shown in primates and in mammals to be a very reliable indicator of an animal's locomotor and behavioral habits."
"As far as looking at the whole body," he added, "it's something we're planning."
A. Afarensis No Match for a Chimp
Despite their differences, the researchers agree on the basics: A. afarensis was an upright walking creature that also climbed trees.
Case Western's Simpson thinks they probably climbed like modern humans, "as opposed to exhibiting any special adaptations to arboreality."
The University of Missouri's Ward agreed, arguing that, if climbing were part of A. afarensis' lifestyle, evolution would have left the species with "the really key bits of climbing anatomy, like the grasping foot."
Another thing they can all agree on: A. afarensis would have been no match for a chimp or gorilla in negotiating the forest canopy, as study co-author Alemseged pointed out.
But Alemseged maintains that the species was nevertheless a natural climber. In the trees, its apelike shoulders, long fingers, and other adaptations, he argues, would have allowed it to overcome the handicap of a bipedal body.
Good thing, too. "A species of small stature with almost no technology, which feeds on leaves and fruits and lives in a very dangerous world, needs to nest, evade predators, and to feed itself," he said.
"For those reasons"—in addition to the fossil evidence—"I think an arboreal lifestyle was an important and key element of Australopithecus afarensis."
Lucy (also given a second
(Amharic) name: dinqineš, or Dinkenesh, meaning "you are amazing" is the
common name of AL 288-1, several hundred pieces of bone representing about
40% of the skeleton of an individual
The specimen was discovered in 1974 at Hadar in the Awash Valley of Ethiopia's Afar Depression. Lucy is estimated to have lived 3.2 million years ago. The discovery of this hominid was significant as the skeleton shows evidence of small skull capacity akin to that of apes and of bipedal upright walk akin to that of humans, providing further evidence supporting the view that bipedalism preceded increase in brain size in human evolution, though other findings have been interpreted as suggesting that Australopithecus afarensis was not directly ancestral to humans. http://en.wikipedia.org/wiki/Lucy_(Australopithecus)
anthropologist are certain she was a biped, but without foot bones, they use
the leg bone to hip bone connection, as well as the spinal connection at the
skull. Upright walkers spines are directly below the skull while apes
and chimps spines enter the skull at an angle. This Lucy
skeleton reconstruction is by the Cleveland Natural History Museum and shows
her with human feet, check the big toe.
The species A. afarensis is one of the better known australopithecines, merely with regard to the number of samples attributed to the species. The species was named by D. Johanson and T. White in 1978. This lead to a heated debate over the validity of the species (seen in a 1980 issue of Science), with the species eventually being accepted by most researchers as a new species of australopithecine and a likely candidate for a human ancestor.
|Early Human Ancestors Had Tool-Using Hands KENT, ENGLAND—Matthew Skinner and Tracy Kivell of the University of Kent, and their colleagues from University College London, the Max Planck Institute for Evolutionary Anthropology, and the Vienna University of Technology, have found skeletal evidence that supports the archaeological evidence for tool use by Australopithecus africanus, an early human ancestor. The team members examined the internal spongey bone structure, called trabeculae, of modern human hands, and the trabecular bone structure in the hands of chimpanzees, and they found clear differences between the two. Chimpanzees are not capable of a forceful precision grip with their hands, which is necessary when turning a key, nor are they able to perform squeeze gripping, as when using a hammer. The team members also examined the hand bones of Australopithecus africanus, and found a human-like trabecular bone pattern in the thumb and palm, suggesting that these early human ancestors would have been capable of such tool-using hand postures between two and three million years ago. Neanderthals also have modern human-like trabecular bone structures. To read about Australopithecus africanus' teeth, go to "Toothsome Evidence."|
bahrelghazali is a fossil hominin that was first discovered in 1995 by
the paleontologist Michel Brunet in the Bahr el Ghazal valley near Koro
Toro, in Chad, that Brunet named Abel. It was dated using beryllium-based
radiometric dating as living circa 3.6 million years ago.
The find consists of a mandibular fragment, a lower second incisor, both lower canines, and all four of its premolars, still affixed within the dental alveoli. The specimen's proper name is KT-12/H1; "Abel" is the informal name, a dedication to Brunet's deceased colleague Abel Brillanceau. The specimen located roughly 2,500 kilometers west from the East African Great Rift Valley.
The mandible KT-12/H1 discovered has similar features to the dentition of Australopithecus afarensis; this has brought researchers like William Kimbel to argue that Abel is not an exemplar of a separate species, but "falls within the range of variation" of the Australopithecus afarensis. By 1996, Brunet and his team classified KT-12/H1 as the holotype specimen for Australopithecus bahrelghazali. This claim is difficult to substantiate, as the describers have kept KT-12/H1 locked away from the general paleoanthropological community, contrary to the International Code of Zoological Nomenclature 1999. This species is a mystery to some as it is the only australopithecine fossil found in Central Africa. It is also of great importance as it was the first fossil to show that geographically there is "a third window" of early hominid evolution.
But there is one other essential piece to this puzzle that leaves no trace in the fossil record. When certain primate females are ready to mate they send strong signals to the other males (a baboon shows a bright red bottom). It is possible that our female hominid ancestors did not know when she was fertile. Therefore, selecting a single male partner became the most viable human characteristic, ovulation that not only goes unannounced to the males of the group, but is concealed even from the female herself. In this scenario regular meals took precedence over being part of a harem. The Female's choice of male partners became the most brave and stealthy who could both kill game and scavenge well. This trait may have resulted in corporation by the males to stay alive, which may also have generated the need for language.
So you thought women began manipulating men in just your life time didn't you, no, no, females figured it out looooooooooong ago - its in their DNA guys. And you know that if you have ever crossed a willowy little fire-tongue.
"This may be the most important specimen in the history of evolutionary biology," said C. Owen Lovejoy, an anthropologist at Kent State University in Ohio, in an interview with ABCNews.com.
Lovejoy was one of more than 40 researchers from around the world who analyzed the Ardi fossils.
Ardipithecus is not the long-sought "missing link" -- the ancestor that scientists say humans and apes have in common -- but comes close. And it helps show that both human beings and apes have evolved from something, about six million years ago, that did not look much like either.
"Six months ago, we would have said our common ancestor looked something like a chimp," said Tim White of the University of California at Berkeley, a senior researcher on the project. "Now all that has changed.
"What we found in Ethiopia at 4.4 million years ago is the closest we've ever come to that ancestor along our own line," White said.
The most complete skeleton, out of more than 30 found, was female, about four feet tall. They discerned the sex from the shape of the pelvis, which was wide enough for her to have borne a baby in her womb.
J.H. Matternes/Science/ABC News Photo Illustration
Artist's conception of what Ardipithecus ramidus would have looked like 4.4 million years ago.
There are older specimens from other locations, but they are not complete enough for the analysis that has now been applied to Ardipithecus.
Walked Upright, but Feet Like a Chimp
The scientists said the fossils show that Ardipithecus walked upright, and that her teeth resemble modern human teeth more closely than they do those of a chimpanzee.
Curiously, though, her feet were capable of grasping, something chimps need in order to climb in trees. She would have been able to climb trees, but she probably did not swing from branches the way modern chimps do.
The back of her skull is small, indicating she had a small brain.
The Ardipithecus bone fragments came from a layer of rock beneath the Afar region of Ethiopia. Afar is now desert, but the scientists said it was woodland 4 million years ago. They found fossilized wood and seeds around the Afar bones.
The fossil hunters, from Ethiopia and the United States, sent the bone fragments they found to a team in Japan. There, 3-D computer models were made of each piece, and the pieces were digitally reassembled, a bit like a jigsaw puzzle.
'Missing Link'? African Fossil Brings Paleontologists Closer
The first fragments were found in 1992, and more in later years. It took this long, said Lovejoy, to put the pieces together so that a detailed description could be published. The results are online in this week's edition of the journal Science.
Ardipithecus is 1.2 million years older than Lucy (Australopithecus afarensis), the famous pre-human fossil found in Africa in 1974. Lucy, like Ardi, walked upright and had a small brain, but was clearly closer to modern human beings -- probably not capable, for instance, of climbing routinely in trees.
So what would life have been like for a primitive being more than four million years ago? Scientists say they can deduce a fair amount from Ardi's skull, jaw, hands, legs and pelvis.
The teeth, for instance, suggest that Ardipithecus was probably an omnivore -- eating anything, plant or animal, that it could find. It did not have the pointed teeth found in modern chimpanzees, useful for eating fruit.
Darwin Would Be Pleased, the shape of the large canine teeth in the front of the jaw is important. Male teeth were not larger than females'. It provides clues about social structure, suggesting that the males of the species did not fight each other for the females' attention.
Instead, said Lovejoy, "It is likely that the males went looking for food and brought it back to the females, possibly in return for sex, though that's another story." He added, "This was probably a species for which male aggressiveness was not something that led to evolutionary success." Scientists have believed since Charles Darwin's time that apes and human beings have common origins. But they have been hampered by the lack of fossils to trace the evolutionary path. White and Lovejoy said that is why Ardipithecus is so important.
"This," said Lovejoy, "fills a huge gap."
This from the Archaeology.org Jan 2014
PHOENIX, ARIZONA—Paleoanthropologist William Kimbel of Arizona State University and his colleagues have examined the base of a partial cranium of Ardipithecus ramidus, the 4.4 million-year-old primate known for its ape-like tiny brain and grasping big toe for climbing, and more human-like small teeth and and upper pelvis capable of bipedal locomotion. Kimbel’s results are in line with earlier studies that show the base of Ardi’s cranium links it to 3.4 million-year-old Australopithecus skulls and those of modern humans. “Given the very tiny size of the Ardi skull, the similarity of its cranial base to a human’s is astonishing,” he said.
Hominid Traits Suggested for A. ramidus Skull
KNOXVILLE, TENNESSEE—The skull base of 4.4 million-year-old Ardipithecus ramidus was short and broad, with a forward-placed opening for the spinal cord, according to a reconstruction of a partial skull base by William Kimbel of Arizona State University. Such features are exclusive to hominids and modern humans. This skull was discovered in 1994, before Ardi, the partial skeleton of an adult female, was first described in 2009. A new analysis of Ardi’s pelvis, which has a mix of monkey, ape, and hominid characteristics, further suggests that Ardipithecus ramidus probably had a slow, two-legged gait on the ground, in addition to tree-climbing abilities.
Sahelanthropus tchadensis was described in 2002 by French paleontologist Michel Brunet and his team. It was discovered in Chad from deposits that have been dated by biostratigraphy to between 6 and 7 million years in age. Central Africa is an unusual place to find hominid fossils, and the conditions under which these paleontological teams work are arduous. Their efforts are invaluable for documenting the geographic spread of hominids across the African continent. Many fossils of other animals were recovered at the same site as Sahelanthropus, suggesting that the habitat, a dry desert today, was then a lush lakeshore with extensive forests around it.
The fossil specimen that was found by Brunet’s team was a badly crushed and distorted cranium. This piece when reconstructed was nicknamed Toumai, which means ‘hope of life’ in the local Goran language. The cranium housed a small brain, estimated to be around 360 cc in volume. This is approximately the same size as a contemporary African ape. It is not surprising that a creature that lived so close to the divergence time of the human and chimpanzee lineages (according to molecular data) should show primitive characteristics. It is currently placed tentatively on the hominin lineage because of its relatively small canine tooth, which is worn down at the tip. In contrast, ape canines are large, projecting, and remain pointed throughout life.
Bipedality (walking on two legs) is one of the most diagnostic characteristics of humans and their ancestors. How can we tell if extinct hominids were bipedal? The position of the foramen magnum (Latin for ‘great hole’) right under the brain is a trait that indicates walking on two legs. The spinal cord exits the skull through this large opening, and so the position of the foramen magnum far forward on the base of the skull demonstrates the upright posture seen in all hominids. In the Toumai skull, the foramen magnum seems to be positioned fairly far forward on the base of the skull. Brunet has interpreted this as indicating bipedal locomotion in Sahelanthropus, though other paleoanthropologists have questioned this conclusion. Unfortunately, without any fossil bones from the postcranial skeleton , its locomotion cannot be unequivocally determined.
The very large brow ridges of Toumai are unexpected. This feature does not appear in human ancestors until Homo erectus, some 5 to 6 million years later. The relative flatness of the facial features is also unexpected. Both apes and later hominins such as australopithecines are characterized by projecting faces. With its mixture of primitive, unusual, and advanced traits, Toumai gives us a glimpse into the early history of the human lineage. However, whether it belongs on our branch or that of the apes cannot be definitively established until more fossils are found.
Credits: Becoming human org
11-million-year-old primate discovered.
April 23, 2010
Scientists have discovered an eleven-million-year-old new primate in a garbage dump in Catalonia, Spain.
Named Pliopithecus canmatensis, after the site (Can Mata in the Valles-Penedes basin), the primate belonged to an extinct family of Old World monkeys, Catarrhini, which dispersed from Africa to Eurasia.
Scientists were able to ID the monkey from fragments of its jaw and molars.
The new species, according to the scientists, sheds light on the evolution of the superfamily Pliopithecoidea, primates that include animals that diverged before the separation of the two current superfamilies: the cercopithecoids (Old World monkeys) and the hominids (anthromorphs and humans). It thrived in Eurasia during the Early and Late Miocene, or between 23.5 and 5.3 million years ago.
“Based on the anatomical, palaeobiographical and biostratigraphic information available, the most probable evolutionary scenario for this group is that the Pliopithecoidea were the first Catarrhini to disperse from Africa to Eurasia, where they experienced an evolutionary radiation in a continent initially deserted of other anthropoids (apes),” David Alba, the project leader and a researcher at the Catalan Institute for Palaeontology at the Autonomous University of Barcelona (UAB), aid.
According to the new study, the subfamily to which this particular species belonged originated from an ancestor called the dionsisopithecine in Asia. This ancestor led to animals that later moved into Europe around 15 million years ago.
Fifteen to eleven million years is somewhat a drop in the time bucket for primate evolution, however. One of the world’s oldest primate-like animals was Plesiadapis, which lived 58 to 55 million years ago. So primate history, our history, goes back a very long time.
The study has been published in the American Journal of Physical Anthropology.
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