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The Evolution of Man
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To adapt to the cold, it may be that Neanderthals (both males and females) had a greater total body mass than modern humans do (or greater than humans back then). Not only that, but I would hypothesize that there seems to be a limiter to the amount of fat or muscle one can have in freezing weather: too much fat mass rids the body of muscular-generated heat and paralysis can occur, and too much muscle mass doesn't have that initial layer of protection that fat has. So, there has to be a very specific compromise between % of body-fat of % of muscle mass to live in these sort of climates. Perhaps this is the reason why polar bears are best adapted to freezing temperatures unlike most animals: they have that perfect or near perfect ratio of muscle mass/body-fat within their total mass. Neanderthals (and other humans in the same environment) might have followed this rule.
Some illustrations of ancient humans of all species:
Neanderthal  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author Homo Erectus  *This image is copyright of its original author Homo Antecessor  *This image is copyright of its original author *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author Hobbit Man  *This image is copyright of its original author
Skulls found in China were part modern human, part Neanderthal; possibly new species
By Ben Guarino March 3 Reconstructions of the skulls superimposed over the site where they were found. (Xiujie Wu)  *This image is copyright of its original author Modern humans outlasted the Neanderthals by about 40,000 years and counting. But don’t pat yourself on the back too firmly for outliving those troglodytes. Neanderthals crafted tools and tamed fire. They cared for their dead. Animal horns and blackened fire pits encircling the remains of a Neanderthal toddler suggest a 42,000-year-old funeral rite. If a Neanderthal indeed wore a talon necklace, as a collection of polished eagle claws indicate, they beat us to jewelry, too. Perhaps one of your ancient ancestors found the claw necklaces sexy: Some scientists theorize humans gave Neanderthals genital herpes and tapeworm parasites. Their proportions, however, remained distinctly Neanderthal. Neanderthal bodies were shorter and stockier, more Gimli son of Gloin than Gigi Hadid. Their skulls were built differently, too, with a few features — like heavy brow ridges — particularly unlike ours. Which makes a pair of newly described skulls something of a wonder. The partial skulls have features up to this time unseen in the hominid fossil record, sharing both human and Neanderthal characteristics. “It is a very exciting discovery,” as Katerina Harvati, an expert in Neanderthal evolution at the University of Tübingen in Germany, who was not involved with the research, told The Washington Post. “Especially because the human fossil record from East Asia has been not only fragmentary but also difficult to date.” Excavators dug up the skull cap fragments in 2007 and 2014, in Lingjing, located in China’s Henan province. The diggers discovered two partial skulls in a site thought to be inhabited 105,000 to 125,000 years ago, during an epoch called the Pleistocene. The owners of the skulls were good hunters, capable of fashioning stone blades from quartz. Ancient bones of horses and cattle, as well as extinct woolly rhinoceros and giant deer, were found strewn near the skull remains. Researchers from the Chinese Academy of Sciences in Beijing and at Washington University in St. Louis described the skulls as having a “mosaic” of features. Writing Thursday in the journal Science, they noted similarities with three groups: The brow ridges of the skulls were modest and the skull bone mass was reduced, like features of early modern humans living in the Old World. The skulls had a broad and flat brainpan, like other eastern Eurasian humans from the mid-Pleistocene epoch. Their semicircular ear canals and the enlarged section at the back of the skull, however, were like a Neanderthal’s. “Eastern Asian late archaic humans have been interpreted to resemble their Neanderthal contemporaries to some degree,” Xiujie Wu, an author of the study at the Chinese Academy of Sciences‘ Institute of Vertebrate Paleontology and Paleoanthropology, said in a statement. “Yet it is only with the discovery of two human crania,” she said, “that the nature of these eastern Eurasian early Late Pleistocene archaic humans is becoming clear.” The large brains of these archaic humans ruled out Homo erectus and other known hominid species, the scientists wrote. The researchers were vague about what they thought the species might be, describing them only as archaic humans. But Wu told Science Magazine that the fossils could represent “a kind of unknown or new archaic human that survived on in East Asia to 100,000 years ago.” Other experts speculated that these skull caps could represent a little-known human relative: the mysterious Denisovans, a species that currently exists only as sequenced DNA taken from finger bone and a tooth found in a Siberian cave. Thought to live some 100,000 to 50,000 years ago, the Denisovans shared genetic material with humans as well as Neanderthals. A 2015 analysis of the specimen scraps indicated that the Denisovans lived for some 60,000 years side-by-side with Neanderthals and humans in Asia. (That humans interbred with Neanderthals is, of course, old news. Many humans who have Eurasian ancestry carry bits of Neanderthal DNA, around 2 to 5 percent of it, within their genes. In the process of swapping DNA, Neanderthals lent us genes for bad skin while boosting our immune responses.) The cranial remains “show an intriguing combination of Neanderthal-like as well as archaic features,” Harvati said. “This would be the combination that one would expect based on the ancient DNA analysis of Denisovans, who were closely related to Neanderthals.” The paper did not mention Denisovans, the study authors said, because DNA extraction attempts failed to yield genetic material. But the lack of even a nod toward the Denisovans in the new report was a point that Philipp Gunz, an evolutionary anthropologist at the Max Planck Institute in Leipzig, found surprising. The fossils, which Gunz called “remarkable,” as he told The Post, “certainly look like what many paleoanthropologists (myself included) imagine the Denisovans to look like.” Time may tell — if scientists can pull off a successful laboratory analysis. “Unfortunately, however, it is not possible to infer skull morphology from ancient DNA directly,” Gunz said. “I therefore hope that future studies will be able to extract ancient DNA from these or similar specimens.”
Late Pliocene environmental change during the transition from Australopithecus to Homo Robinson, Rowan, Campisano, Wynn & Reed, 2017
Abstract: "It has long been hypothesized that the transition from Australopithecus to Homo in eastern Africa was linked to the spread of open and arid environments near the Plio−Pleistocene boundary, but data for the latest Pliocene are scarce. Here we present new stable carbon isotope data from the late Pliocene mammalian fauna from Ledi-Geraru, in the lower Awash Valley (LAV), Ethiopia, and mammalian community analyses from the LAV and Turkana Basin. These data, combined with pedogenic carbonate stable isotopes, indicate that the two regions were largely similar through the Plio−Pleistocene, but that important environmental differences existed during the emergence of Homo around 2.8 million years ago. The mid-Pliocene to late Pliocene interval in the LAV was characterized by increasingly C4-dominated, arid and seasonal environments. The early Homo mandible LD 350-1 has a carbon isotope value similar to that of earlier Australopithecus from the LAV, possibly indicating that the emergence of Homo from Australopithecus did not involve a dietary shift. Late Pliocene LAV environments contrast with contemporaneous environments in the Turkana Basin, which were more woody and mesic. These findings have important implications for the environmental conditions surrounding the emergence of Homo, as well as recent hypotheses regarding Plio−Pleistocene environmental change in eastern Africa." Other articles related: Grassy beginning for earliest Homo
Potential hominin affinities of Graecopithecus from the Late Miocene of Europe Fuss, Spassov, Begun & Bohme, 2017
 *This image is copyright of its original author Painting of Graecopithecus freybergi. Reconstruction credits: Velizar Simeonovski  *This image is copyright of its original author Fig 1. Studied specimens and virtual reconstructions of the holotype of Graecopithecus. a, Type mandible of G. freybergi from Pyrgos, Greece. b, RIM 438/387 –Left P4 of cf. Graecopithecus sp. from Azmaka, Bulgaria. From left to right: distal, mesial, lingual, buccal, occlusal and apical. c-i, μCT based 3D reconstructions of the type mandible showing the partially preserved roots and pulp canals from c-m3 and the crowns of right p4-m2. Further images with a magnification of the virtually isolated teeth and pulp canals are provided in S1 Fig. c, Occlusal view. d-e, Apical view. f, Buccal view of the left hemimandible. g, Buccal view of the right hemimandible. h, Lingual view of the left hemimandible. i, Lingual view of the right hemimandible. Scale bars, 10 mm. show less Abstract: "The split of our own clade from the Panini is undocumented in the fossil record. To fill this gap we investigated the dentognathic morphology of Graecopithecus freybergi from Pyrgos Vassilissis (Greece) and cf. Graecopithecus sp. from Azmaka (Bulgaria), using new μCT and 3D reconstructions of the two known specimens. Pyrgos Vassilissis and Azmaka are currently dated to the early Messinian at 7.175 Ma and 7.24 Ma. Mainly based on its external preservation and the previously vague dating, Graecopithecus is often referred to as nomen dubium. The examination of its previously unknown dental root and pulp canal morphology confirms the taxonomic distinction from the significantly older northern Greek hominine Ouranopithecus. Furthermore, it shows features that point to a possible phylogenetic affinity with hominins. G. freybergi uniquely shares p4 partial root fusion and a possible canine root reduction with this tribe and therefore, provides intriguing evidence of what could be the oldest known hominin." Other articles related: The Oldest Hominins Could Have Lived in Europe, Not Africa, Claims New Study 
Good job, Ngala. Very interesting.
Would you be able to do a post about the origin of man when you have time? A post in which you combine what is known, including the recent info from southern Africa? I'm interested in evolution, but often lack the time to read. My guess is I won't be the only one interested in a kind of overview on the evolution of man.  (05-24-2017, 12:11 AM)peter Wrote: Good job, Ngala. Very interesting. Maybe this European ape was the ancestral species of the later Australopithecus? BTW, I think the ultimate origin of the Homininae subfamily (Gorilla/Chimpanzee/Human) is indeed Africa, but some early ancestors of humans could have been migrated out of Africa, then later migrated back? Could be the Australopithecus descended from the back migration of the later Graecopithecus?
Interesting questions @GrizzlyClaws.
Graecopithecus, found in southern Greece, has been dated around 7.37–7.11 Ma, but before so far was been considered the oldest Hominini known Sahelantropus tchadensis (Djurab desert from Chad) that is dated around 7 Ma (7.2–6.8 Ma is proposed by Lebatard et al., 2008), but very close; Graecopithecus is not considered an ape, but a direct ancestor of the genus Homo and the last common ancestor between the Homo and Pan (human and chimpanzees), before their divergence. With this data and these information, i think that there are two possible theories about the evolution of these interesting early hominin: 1 – Sahelantropus and Graecopithecus is derived from a common ancestors (missing ring) that occupied the eastern mediterranean land like the Balkans, Greece peninsula, Middle East from the mediterranean sea and north east Africa; they have been divided by the progressive desertification of northern Africa, leading a two separeted species, with the Graecopithecus which evolved into a “not ape” hominid earlier to the Sahelantropus; 2 – Sahelantropus is a discendent of Graecopithecus (and much further on the evolutionary line of the Australopithecus, around 4-2 Ma); this last is developed into Balkans and Greece peninsula, he migred in north Africa and he settled in north eastern Africa. They have separeted from the progressive desertification, with a subsequently diverisfication. Another hominid was found in northern Greece and has been dated around 9.6–8.7 Ma, Ouranopithecus macedoniensis, the direct ancestor of Ouranopithecus turkae (8.7 – 7.4 Ma) from central Anatolia. This means that the migrations are frequently, and i think that we can not exclude that the ancestors of the genus Homo that has split from Pan genus was happened in the eastern mediterranean region, and subsequently he migrated to Africa.
Excellent theory, so the common ancestor of Homo and Pan was a branch of Homininae that proceeded a back migration loop between Africa and Europe.
Just like the common ancestor of the modern human and Neanderthal AKA Homo heidelbergensis was also a species that trespassed between Africa and Europe. The modern human Homo sapiens was born in Africa, but their direct ancestor Homo heidelbergensis was a species that initially moved from Africa to Europe, but it later moved back to Africa and gave the birth to the modern human, when dwelled in Europe, they also gave the birth to the Neanderthal.
The position of Homo heidelbergensis in the tree of human evolution is very discussed. There is suggestion that Homo antecessor is the last common ancestor between Homo sapiens and Homo neanderthalensis, and Homo heidelbergensis is consider only an archaic form of Homo sapiens, a transition hominid with characters of H. erectus and H. sapiens (reply #27 on this thread have info on the position of H. heidelbergensis).
This is another study on Graecopithecus: Messinian age and savannah environment of the possible hominin Graecopithecus from Europe Bohme et al., 2017 Abstract: "Dating fossil hominids and reconstructing their environments is critically important for understanding human evolution. Here we date the potentially oldest hominin, Graecopithecus freybergi from Europe and constrain the environmental conditions under which it thrived. For the Graecopithecus-bearing Pikermi Formation of Attica/Greece, a saline aeolian dust deposit of North African (Sahara) provenance, we obtain an age of 7.37–7.11 Ma, which is coeval with a dramatic cooling in the Mediterranean region at the Tortonian-Messinian transition. Palaeobotanic proxies demonstrate C4-grass dominated wooded grassland-to-woodland habitats of a savannah biome for the Pikermi Formation. Faunal turnover at the Tortonian-Messinian transition led to the spread of new mammalian taxa along with Graecopithecus into Europe. The type mandible of G. freybergi from Pyrgos (7.175 Ma) and the single tooth (7.24 Ma) from Azmaka (Bulgaria) represent the first hominids of Messinian age from continental Europe. Our results suggest that major splits in the hominid family occurred outside Africa."
From what I known is that Homo habilis is considered as the last common ancestor between Homo sapiens and Homo erectus.
Homo sapiens is not a direct descendant of Homo erectus from Asia, but from Homo ergaster instead; an African variant of Homo erectus. Homo antecessor evolved from Homo ergaster that migrated from Africa to the Southwest Europe, while Homo heidelbergensis evolved from a population of Homo antecessor in the Central Europe. Later on, Homo heidelbergensis split into two groups; the one that stayed in Europe evolved into Homo neanderthalensis, while the one that returned to Africa evolved into Homo sapiens. Here is the latest transitional form between Homo heidelbergensis and Homo sapiens: Homo rhodesiensis. https://en.wikipedia.org/wiki/Homo_rhodesiensis Homo rhodesiensis already closely resembled to the modern bush men in South Africa, and I do believe they should be considered as the most archaic form of the modern human.  *This image is copyright of its original author  *This image is copyright of its original author
Homo sapiens: Homo habilis (Africa) -> Homo ergaster (Africa) -> Homo antecessor (Europe) -> Homo heidelbergensis (Europe) -> Homo rhodesiensis (Africa) -> Homo sapiens (Africa)
Homo neanderthalensis: Homo habilis (Africa) -> Homo ergaster (Africa) -> Homo antecessor (Europe) -> Homo heidelbergensis (Europe) -> Homo neanderthalensis (Europe) Homo erectus: Homo habilis (Africa) -> Homo georgicus (West Asia) -> Homo erectus (East Asia) Hopefully this could be intuitive to demonstrate the evolutionary path of the human family.
Thank you @GrizzlyClaws for the many lineage.
Suggestions say that Homo heidelbergensis is not a real different taxa, but it's only an ancient form of Homo sapiens, and Homo rhodesiensis is an intermediate form; so we can consider both species Homo sapiens. Moreover, Homo antecessor would be the last common ancestor between us, Homo sapiens, and Homo neandethalensis, before the divergence. This theory would not be so impossible, since in fact, on H. heidelbergensis and H. rhodesiensis there are no such distinctive characters to speak of species but only a local difference, so we can talk an archaic form and transition form. This would be the scheme: Homo antecessor => Homo neanderthalensis (Extinct) =>H. heidelbergensis (archaic H. sapiens)=>H. rhodesiensis (transition between H. heidelbergensis and H. sapiens)=>Homo sapiens
So does this mean that H. heidelbergensis and H. neanderthalensis should be considered as the sister species to each other?
H. neanderthalensis was the one that stayed in Europe, while H. heidelbergensis migrated back to Africa and evolved into an intermediate form known as H. rhodesiensis. If Africa is the ultimate origin for H. sapiens, then Europe should be considered as the penultimate origin. Except Africa, the ancestor of the modern human had also explored Europe way before exploring any other continents. Africa -> Europe -> Asia -> Oceania -> America |
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