Ramapithecus - 2 | Anthropology Optional for UPSC PDF Download

Homo Habilis

• The first H. habilis, described in 1964, came from Oluvial Gorge in Tanzania. The original material was fragmentary, sufficiently so to provoke some controversy over whether a species distinct from south African A. africanus was truly present; H. habilis was said to have had a larger brain and smaller cheek teeth. Since then, more material has been found at Olduvai, Omo and east Turkana where several relatively complete crania were found including ER 1470 from east Turkana. The age of ER 1470 was originally thought to be in excess of 2.6 million but it is now dated around 2 million years.
• Homo habilis consist of several reasonable crania, some jaws and teeth, and a few unassociated post-cranial. There are disagreements over the number of species being sampled. If it so only one there is a considerable range in rain volume, A small number of larger crania cluster around 500 cc. These group differ in tooth size, the former having larger teeth including canines and facial morphology differs markedly between the best preserved representative of each group, ER1470 and ER1813 both from east Turkana. If these are males and females the degree of brain, tooth and face size dimorphism is considerably greater than in any living species.
• We assume here that two species are probably being sampled, Homo habilis and smaller brained species superficially resembling A. africanus. Homo habilis specimens are known from a little before to little after 2 million year ago from east Turkana, Olduvai, probably Omo and possibly Sterkfontein. Body size is poorly known and degree of dimorphism is unclear but some individuals weighed 40-50 kg.
• Brain size ranged between 650-800 cc. and an endocast shows some frontal lobe features not seen in australopithecines and supposedly characteristics of Homo sapiens. It has been suggested that these imply speech capabilities. The brain case is rounded, and resembles an enlarged, allometrically scaled version of A. africanus.
• The face was large and deep, with big inceasers and canine and large cheek teeth . wear patterns on molar and pre molar broadly resemble those of Australopithecus. Post cranial are difficult to assign, but an innominate, femur, and tibia are probably habilis. The pelvic and leg bone differ from homologues of Australopithecus and resembles those of H. erectus, being similar to modern human bones, but more robust.
• They imply a positional repertoire, gait, and ranging pattern more similar to humans than to australopithecines.

General Characteristics

• The cranial capacity ranges between 650-800 cc. The cranial capacity was greater than that of australopithecines and approached that of H. erectus. The brain to body size ration also suggested evolutionary advancement.
• Unlike australopithecines the frontal lobes (seats of mental ability) of brain were well developed they almost approximated that of modern man. The cranial vault was rounded.
• Hominid dental structure : the premolars are particularly humanlike.
• The mandibles (lower jaw) are comparatively less massive than that of australopithecines. However the dental arcade was not parabolic.3
• The Hind limb morphology clearly approached the human foot.
• H. habilis was a tool maker. The tool kit is referred to as "Olduwan Industry." It included cutting tools, scraping tools and tools to make tools. Meat, plant and wood were worked upon. Bones, seeds and nuts were cracked open. There is an evidence of camp sites also.
• Larger brain involves gestation, larger new born and greater longevity. The brain enlargement was perhaps the cause and the effect of dietary shifts in H. habilis.

The distribution of H. habilis and P. boisei overlaps. Both are found in east Africa during 2-1 million year ago. Homo habilis originated from some gracile australopithecines and represents a massive increase in brain size in short span of time. Some scholars disagree to the view that these are true Homos. Their teeth are large relative to their body size and their limb proportion shows that they are closer to australopithecines than Homo. Some even suggests placing these fossils in separate genus.

Phylogenetic Implications

• There has always been a question haunting the student of paleo-anthropology, why homo habilis, not aethiopithecus habilis?
• One of the main criteria of for inclusion in the genus Homo was brain size. Different authorities had different threshold sizes, ranging from 700-800 cc. Most australopithecines were around 500 cc, while Homo erectus was above 1000 cc. What of H. habilis?
• For some authors the brain size was more than 600 cc would suffice for inclusion in homo, along with the other feature indicated by the fossils, such as upright posture and bipedal walking and the precision grip in the hand. The first Homo habilis specimen had a brain size estimated at 680 cc.
• With the discovery of Olduwan tool tradition, the discussion centered on tool making. Many authorities were unhappy about tools as admissible evidence in support of this new species. The history of hominid fossil discovery is littered with names coined in excitement of a new find. Many of these names have not stood the test of time.
• In the mid-1960s many people thought it probable that homo erectus had evolved from some type of australopithecine. Therefore it would be natural to find fossils representing transitional forms-the result of evolution in action. Rather than create a separate species, this new form should be placed either with its predecessors, the australopithecines or with its successors, Homo erectus. According to Le Gros Clark, Homo habilis can be easily accommodated within A. africanus.
• There were plenty of other opinions about where Homo habilis fitted into the hominid evolutionary tree. Leaky long held the view that our modern species, Homo sapiens was in fact very ancient and could be direct descendent of homo habilis. This would push Homo erectus out on to a limb, making it our cousin and not our ancestor.
• In 1972 Richard discovered a skull at Koobi For a which had a cranial capacity of 800 cc . A brain size of this surely meant the creature to be member of genus Homo ?
• Till today more than 20 Homo habilis individuals have been found. Besides having a bigger brain than australopithecines, Homo habilis also had a higher brain to body ratio compared to apes, the temporal lobes which deal with memory and other mental functions are more developed; so are the parietal lobes which analyse information coming in from senses and he speech processing area is also developed.
• The version of our evolutionary tree in which A. afarensis gave rise to H. habilis which evolved into Homo erectus, which in turn Homo sapiens has an appealingly neat straight line feel to it. But standing back from the main habilis time period about1.9 - 1.6 million years ago brings various complications.
• What about before the habilines? An alternative to the afarensis-habilis-erectus-sapiens view is that "early Homo" was already living more than 3 million years ago. Gradually the early homo became Homo sapiens. Whether it passed through the habilis stage on the way is an area lively debate.
• What about after the habilines ? by 1.6 million years ago, another human species had appeared the taller, long legged, bigger brained Homo erectus. If habilis did evolved into erectus, could such a great evolutionary change have taken place so quickly ? one possibility is punctuation- a rapid burst of change in the type of evolutionary process known as punctuated equilibrium. Another is that some relatively isolated habilian populations began to evolved into erectus at much earlier date, leaving the rest of their kind to continue unchanged, and eventually go extinct about 1.6 million year ago.
• The time between 2 and 1.5 million year ago has been called the crucial humanizing period. Recent fossils find from this time have widened the debate as to how many species of hominids lived in Africa then, and who evolved into what. More fossils may serve to clarify the picture of further to confuse it.

Homo erectus

• The study of fossil primates is the most essential requirement in order to study the emergence and development of man. At the beginning of 19th century, with the emergence of paleontology, comparative anatomy geology etc. the relations of man's antiquity were established by studying the fossil evidence.
• Fossils are relics or traces of a former living things or plants preserved in rocks that are unchanged in structure. In tracing the ancestry of man, physical anthropologists have concentrated their attention to fossil primates.
• The quaternary period, especially the Pleistocene epoch may be regarded as the age of fossil remains viz. ape like man, early man and Homo sapiens.
• Three major stages which have been recognized in relation with hominid evolution are as follows:
  • Australopithecines stage.
  • Homo erectus stage.
  • Neanderthalensis stage.
• Australopithecine fossils lasted from about 5.5 - 1.5 million years B.P. (before present). They shared bipedal locomotion with the Hominids. These fossils belonged to various parts of Africa. In South Africa, Australopithecus africanus group were discovered at a place called Taung and Paranthropus robustus at Kromdraai.
• In East Africa also Zinjanthropus boisei and Homo habilis were discovered at Olduvai Gorge. Australopithecus was again discovered from West Africa. Among these fossils, it is suggested that Homo habilis should be placed with the members of the later hominids.

Homo erectus

• The period between 2 to 1.5 million years B.P. (before present) provides reasonable points of transition from some of the Australopithecines to Homo. By about this time skull and jaws of Robust australopithecines were found indicating that this robust type continues to exist after the evolutionary appearance of Homo erectus. And the period between 1.5 to 125,000 years BP is regarded as the transition from Homo erectus to Homo sapiens. Under Homo erectus, different generic names such as Pithecanthropus erectus, Sinanthropus pekiinensis and Atlanthropus mauritanicus are placed.
• The specific name Homo erectus derived from Pithecanthropus erectus was given to the finds from Indonesia in the 19th century and when they were sufficiently distinct from human, they were given a separate generic name known as Homo erectus. The term Homo erectus means erect man.
• Homo erectus fossils have been discovered in many parts of the world, including Java, China and North, East and perhaps South Africa but rarely from Europe. In North Africa, three complete lower jaws and a piece of skull cap similar to that of the fossils found in China were discovered.
• In East Africa from Olduvai Gorge, Marry Leaky found a brain case that looks like Asian Homo erectus. In South Africa, a part of a skull and face were discovered at a site called Swartkrans. At this site, robust Australopithecines were accumulated at one time.
• Earliest fossil finds are molar tooth, a skull cap (1891) and a femur (1892) of Homo erectus were described by Eugine Dubois. The finds were discovered on Sole river in central java. Before this discovery Ernst Hackel, a German scientist had proposed that if and when a link between apes and man is found it should be named pithecanthropus (ape man) the finds were accordingly named Pithecanthropus erectus.
• Another juvenile skull (of a child, less than 2 years in age) that bore striking resemblance with the earliest found fossils, and discovered by H. R. Von Koenigswald in eastern Java was given the name of Homo modjokertensis.
• Soon after, two skull caps of the species were discovered at a near by site, Koenigswald believed that the fossils closely resembled those of the Pithecanthropus erectus. During world war II Japanese took over Java, Koenigswald was made a prisoner and fossils were confiscated. Meanwhile, in anticipation of all this he had already distributed the casts of the fossils to his friends. Fortunately, to his pleasant surprise Koenigswald was released after the war and all his belongings including the wealth of fossils were returned to him.
• But the fossil finds of china met different fate. The first fossil of the species, a few teeth, found at Zhou-kau-dein between 1921 to 1927 after thorough study by D. Black were assigned the namw of Sinanthropus pekintensis. Black had realized well that the species was different from our own. In 1929 W.C. Pei, for the first time, discovered the skull of Sinanthropus.
• By 1937 the site had yielded skulls, teeth and other fossil bones of about 45 hominid individuals, along with stone tools, bones of thousands of animals and evidence of fire.
• The area in 1941 was under Japanese control while the fossil expedition was being undertaken by Americans. Sensing a threat to survival of fossils, the fossils were packed and shipped to U.S.
• But as ill luck would have it the sip was captured, the fossils disappeared never to be seen again. Today whatever we know of Zhou-kau-dein fossils is based their casts prepared before this mis-happening. The Homo erectus name was given by Beuttner Janusch as late as 1960s to all fossils mentioned above. Till date H. erectus fossils have been found in Indonesia, China, Algeria, Morocco, Tanzania, Germany and Hungry.
• European fossils are however awaiting authenticity. The earliest fossils describes by Dubois is popularly known as Java-man. The man was an individual who stood tall at 5.8 inches. The skull cap is primitive with heavy brow-ridges and with a cranial capacity of 750-900 cc (between ape and man). Femur bone a well-developed linea aspera.
• Most information of Homo erectus we have today is however based on14 skulls 147 teeth and a few post cranial fragment of about 45 individuals made available from Zhou-kau-dein caves which H. erectus inhabited for a thousand years or so. The fossil finds of Java popularly known as java man have been given the name of H. erectus.
• While those of the China have been placed in a separate sub species of H. erectus pekiinensis. The two sub species of erectus differ only marginally. The skull vault of pekiinensis. Is slightly higher and brow ridges tend to curve more. In lateral view pekiinensis forehead rises at a steeper angle than in its erectus counterpart.
• Compared to Peking Man, Java Man has more massive jaws and teeth. Following information belongs to H. erectus as a species and not to any individual fossil.

Anatomical Features

• Optic lobes of brain are less developed than man,
• Parietal lobes comparatively well developed (power of articulation of Thoughts);
• Cranial capacity between 925 cc (in 8 or 9 year old child) ad 1225 cc (within human range);
• Jaws and teeth large with space between teeth,
• Dental arcade more parabolic than apes,
• Science of taurodontism (enlarged pulp cavities; also found in Neanderthal and some modern Man) upper inceasers showed shaped with sides seeming to curve inwards (mongolide traits),
• No diastema or chin, nose broad and low ridges;
• Man above five feet and women slightly less tall.
• In post cranial anatomy erectus resembled modern man.

Cultural Advancements

• Homo erectus was the first perennial tool makers. Tool bearing sites spread from north-west Europe to south east Asia are much more numerous than the sites yielding fossils. The stone tool culture of mid-Pleistocene origin have been generally ascribed to Chellean and Acheulian traditions. Choppers and chopping tools found mainly in China are restricted in distribution up to central Asia, while hand axe is the most common tool in other parts of the world.
• H. erectus, in the absence of any defence organ used these tools for hunting. Hand axe was a multipurpose tool that could be used for cutting, chopping, scrapping, boring etc. and throwing at the animals. So essential was the use of stone tools that at Zhou-Kou-Dien stones for making tool were brought from a distance of more than 3 kilometers.
• The earliest evidence of news of fire by erectus is seen in China some five lakh years ago and much later at Vertess-zollos in hungry Terra Amata in France. Fire could be used in a number of ways. It provide security, protection from predators, warmth at night and of course light. It provided for a group center and increase the working capacity in terms of working hours.
• It also helped in splitting stones from bigger rocks . only fire could sustain erectus in colder regions like in northern china. In caves sites where fire has been located presence of charred bones indicates that (at least occasionally) fire was used to cook food. Homo erectus was a hunter gatherer. At Torralba in Spain, Howell has discovered a mud hole that was used to trap big animals.
• Here the bony remains of more than 40 elephants bear testimony to the hunting skills of middle Pleistocene hunters. Similarly at Olorgesalie in Kenya remains of more than fifty giant baboons (as a troop) are found that must have been cornered by homo erectus. Nowhere has been found the evidence of deliberate burials and we feel handicapped in understanding the rituals, if any, of this early homo species.

How did erectus communicate? Had he developed language?

• These questions cannot be answered in yes or no. We do not have the brain of Man's ancestor available with us. The facts are however inferred through the study of available skulls, crania and skull caps. Traditionally man's large brain has been given the credit of development of speech.
• It is not true otherwise the whale and elephant too could have enjoyed this fantastic gift of nature. Even in brain body weight ratio, capuchin monkey possess one gram of brain for 17.5 grams of body the same ratio for man is 1:44. The brain body weight ratio too is not a good indicator in this regard. The development of brain therefore should be understood in terms of its use and not as a proportion to body weight or its overall size.
• Major areas in brain are present in man, apes and some other mammals alike but none other than man can communicate through a verbal language. Animals communicate through symbols and gestures. Australopithecus with the development of brain in the range of that of great apes does not seem to have had a language.
• It seems that development of brain for this purpose has been the result of group hunting and social life over millions of years. This could easily have resulted in the development of memory areas in the occipital lobe as also the areas of ideas in the frontal lobe. The development of language in some people followed by the selective advantage conferred on them must have resulted in the spread of lingual communication.
• The development of different motor areas through a regular practice of stone throwing and game play too must have contributed in their own way. The development of language is followed the progress in tool technology. The modern complex language is however attributed to the arrival of modern man.

Homo Erectus-Phylogenetic Position

• Bones of cranial vault - very thick
• Strongly developed supra orbital torus extending above, the orbits as an un interrupted bar of bone
• Receding frontal bone
• Well-developed occipital ridge that extended into the supramastoid region and produced an angular contour to the occipital bone.
• Small mastoid process
• Greatest width of cranial at the level of ear lobes
• Broad nasal bones
• Pronounced alveolar prognathism
• Massive body of mandible
• Frequent occurrence of multiple mental foramena.
• Larger upper inceasers.

He however exhibited several characters which place him closer to modern man compared to his predecessors these are:

• Cranial capacity overlaps the lower range of that in H. sapiens and the cranial vault is inflated.
• Increased flexion of face on the brain case (compared to Australopithecus) so that the anterior cranial fossa extends well over the orbits.
• Relative size of face reduced more than in Australopithecus
• Foramen magnum positioned more anteriorly than in Australopithecus
• Conformation of tempero-mandibular joint as in H. sapiens
• Dental arcade parabolic in shape
• Dental morphology more like H. Sapiens than Australopithecus
• Limb bones indistinguishable from those of H. sapiens in shape and size.

H. erectus is thus more advanced than even the most evolved australopithecines i.e. H. habilis but certainly less evolved than H. sapiens.

Heidelbergensis

• On October 21, 1907 was discovered a mandible that is now popularly known as Mauer jaw or Homo heidelbergensis. The discovery was reported by Otto Schoetensack, a professor of anatomy in Heidelberg University in 1908. The fossil was discovered was 65 feet below ground level. It was the first human fossil material recovered from middle Pleistocene of Europe.
• Ascending rami being extremely broad (60mm against an average of 37 mm in modern man) appear square. Upper surface of ramus (mandibular notch) is comparatively shallow. Coronoid process is present at a lower level than condyle and is blunt (similarity with gibbon).
• Horizontal rami are large with a maximum thickness (23 mm against 14 mm in modern man) at level of third molar the symphysis has a convex and receding curve externally (like apes unlike man) and is quite thick (17 mm).
• Fifth cusp, though small, is present in all the molars and there are large pulp cavities. With this combination of simian and human features, Schoetensack concluded that the fossil represented a stage between ape and man. Duckworth suggested the inclusion of Mauer jaw in genus pithecanthropus. While opposing Duckworth views Boule and Valloi consider it as an ancestor of Homo Neanderthalensis of western Europe.
• Presently, however the jaw is placed by some in homo erectus with a different sub species of heidelbergensis; while some others consider it as early Sapiens.
• The Mauer deposits have been dated to about three lakh sixty thousand years ago and this reflect the age of Mauer Jaw.

Transtion to Homo Sapiens

• Genus Homo evolved about 2 million years ago and erectus was probably the first Homo species. It however took erectus over one and half million years to evolve into the modern species of sapiens. The cave of Arago in Pyrenees Mountains of southern France have yielded a skull and several mandibles belonging to the ending phase of the middle Pleistocene, Riss glaciation, which belong to individuals more advanced than homo erectus but less so than the sapiens. In Java where the fossils of erectus and sapiens have been unearthed, recent discovery of some skulls at Sangiran clearly speaks of the continuity of erectus into sapiens. The fossils have been placed intermediate between the two species.
• The Swanscombe skull found near river Thames, England is less than half a million years old. The skull walls were thin than Beijing Man, the inion is is below the opisthocranion resulting in rounder contour of the skull. The maximum breadth of the skull lies not near the base but higher up on the parietals. The pattern of mid-mengeal vessels, is more complex, all these features put Swanscombe skull more close to homo sapiens.
• Another middle Pleistocene skull similar to the Swanscombe skull has been discovered in Steinhein, near Stuttgart, Germany. Popularly known as Steinhein Skull, it has walls further thin in the range of homo sapiens while the cranial capacity approx. 1185 cc is less than that of Swanscombe skull which is approx. 1300 cc.
• Other features in the two skulls are similar. The two skulls discovered at Fontechevade have features more advanced than the Swanscombe or the Sreinhein skull. These fossils belonging to upper Pleistocene with a cranial capacity of about 1450 cc and absence of thick brow ridges are further closer to the sapiens. All the above mentioned fossils belonged to the transitional phase of the Human evolution. The fossils are marked by greater cranial capacity, greater development of skull intermediate between H. sapiens and H. erectus, and nuchal lines below the opisthocranion. The fossils represent represents a form ancestral to homo sapiens. Obliviously, H. erectus during the later mid-Pleistocene and early upper Pleistocene was evolving into H. sapiens.

Neanderthal Man (Homo Neaderthalnsis) 

• Neanderthal Man derives his name from Neanderthal (Neander Valley) Dusseldorf, Germany, where his fossils were found and described first.
• The earliest fossils of Neanderthal Man comprising of a skull cap with upper margin of the orbits, parts of pelvis, two femurs, two humeri, two Ulnas, five ribs and one each of radius clavicle and scapula were found in Neanderthal, Dusseldorf, Germany. The individual, an adult had an estimated cranial capacity of 1230 cc . Post cranial parts so heavy musculature marks but structurally are exactly like the present - day bones. Today Neanderthal fossils are known from Spain, France, Italy, Germany, Slovakia, Hungry, England, Yugoslavia, Israel, Iraq, Libya, Lebanon, Morocco , Russia, Java, China and Pakistan.
• His cultural finds however are much more numerous and have been found in many other countries of the world. Most of the fossils finds belong to the last interglacial and last glacial. The individual is worthy to be placed in the evolutionary ladder between Homo erectus & Homo Sapiens.

Anatomical Features

• Increased brain size & large capacity.
• Dolichocephalic, skull wall and brow ridges thick
• Heavy chinless Jaw.
• Some facial prognathism forwardly projected upper jaw.
• Frontal part not fully developed.
• Comparatively broad nose
• No canine fossa (Unlike man) instead slight puffing out of the bone region.
• Heavily muscled thick neck.
• Barrel chested with powerful muscles of legs and arms
• Sylvan fissure (expression of language) in brain well developed but less developed pharynx.
• Stature 5 feet or more.

Cultural Advancement

• The first known species to have control of fire about 50000 years ago.
• The choppers and chopping tools were replaced by the use of hand axe in Europe and Africa.
• In Asia however OVATE cleavers become popular.
• In Africa there is continues evolution of tools from crude, heavy Chellean hand axe to better made Mousterian hand-axes.
• Flake tools become more and more common with time, most common techniques for getting flakes being prepared/core and Levalloisian.
• The most common flake tool was the "Point" probably used by hafting into the end of a spear.
• Scrapers were also commonly used. The blades, found in low frequency in the early stage become more common in the later period & probably continued into upper Palaeolithic of modern man.
• Probably had strong social organisations, otherwise La Chappelle man as also the handicapped one of the Shanidar could not have survived in old age.
• With Neanderthal we find the first direct evidence of prevalence of rituals as also the deliberate burials.
• In Tashik-Tash (erstwhile USSR) the burial of young Neanderthal was surrounded by wild goat skulls with horn pointed towards the burial.
• In Monte Cicero (Italy) the skull has been broken from the base to extract brain.
• Tools are most commonly found associated with the dead. At Shanidar too, the association of dead with arrangement of bear skulls as also the floral offerings indicates some form of primitive religious practices.