(01) H. floresiensis | The Smithsonian Institution's Human ... · The genus name Homo is the Latin...

(01) H. floresiensis | The Smithsonian Institution's Human Origins Program

Remains of one of the most recently discovered early human species, Homo oresiensis(nicknamed ‘Hobbit’), have so far only been found on the Island of Flores, Indonesia. Thefossils of H. oresiensis date to between about 100,000 and 60,000 years ago, and stonetools made by this species date to between about 190,000 and 50,000 years old. H.floresiensis individuals stood approximately 3 feet 6 inches tall, had tiny brains, large teethfor their small size, shrugged-forward shoulders, no chins, receding foreheads,and relatively large feet due to their short legs. Despite their small body and brain size, H.floresiensis made and used stone tools, hunted small elephants and large rodents, copedwith predators such as giant Komodo dragons, and may have used fire.

The diminutive stature and small brain of H. oresiensis may have resulted from islanddwar sm—an evolutionary process that results from long-term isolation on a small islandwith limited food resources and a lack of predators. Pygmy elephants on Flores, nowextinct, showed the same adaptation. The smallest known specieso f Homo and Stegodon elephant are both found on the island of Flores, Indonesia. However, some scientists are now considering the possibility that the ancestors of H.floresiensis may have been small when they first reached Flores.

One of our own scientists, Dr. Matt Tocheri , does research on this enigmatic early humanspecies; read more about this work, and watch a video about it on this page.

History of Discovery: History of Discovery:

A joint Indonesian-Australian research team found LB-1—a nearly complete femaleskeleton of a tiny human that lived about 80,000 years ago—in Liang Bua cave on theisland of Flores, Indonesia. The skeleton’s unique traits such as its small body and brain sizeled scientists to assign the skeleton to a new species, Homo oresiensis, named after theisland on which it was discovered.

Homo floresiensis | The Smithsonian Institution's Human Origins Program

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http://humanorigins.si.edu/evidence/human-fossils/species/homo-floresiensis

(01) H. floresiensis | The Smithsonian Institution's Human Origins Program

Since the initial nd, bones and teeth representing as many as 12 H. oresiensis individualshave been recovered at Liang Bua—the only site where H. oresiensis has been found sofar. The bulk of the nds related to H. floresiensis date between 100,000 and 60,000 yearsago, with stone tools made by this species dating between 190,00 and 50,000 years ago.

We don’t know everything about our early ancestors—but we keep learning more!Paleoanthropologists are constantly in the field, excavating new areas with groundbreakingtechnology, and continually filling in some of the gaps about our understanding of humanevolution.

Below are some of the still unanswered questions about Homo oresiensis that may beanswered with future discoveries:

1. Which hominin species made the 1 million year old stone tools found on Flores?2. How did these early humans manage to get to the island of Flores?3. D i d H. oresiensis have language, make art, and have other forms of cultural

expression?4. Did H. oresiensis and our species, H. sapiens, ever come into contact with one

another?5. Was a volcanic eruption on Flores the reason H. floresiensis went extinct?6. How similar is the DNA of H. oresiensis to the DNA of other human species? So

far, no DNA has been retrieved from the bones of a H. floresiensis individual.

Homo floresiensis | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/evidence/human-fossils/species/homo-floresiensis

https://australianmuseum.net.au/image/Front-view-of-Homo-floresiensis-skull/

(02) Homo floresiensis - Australian Museum

One of the most controversial and surprising hominin finds in a century.

Front view of Homo floresiensis skull Photographer: Carl Bento © Australian Museum

Homo floresiensis - Australian Museum

https://australianmuseum.net.au/homo-floresiensis


Con icting interpretations and debates surround the remains of these tiny humans fromIndonesia. H. oresiensis are not our ancestors but their unusual features and recentsurvival suggests our human family tree is more complex than once thought.

Background of discoveriesAge

The human remains date from about 100,000 to 60,000 years old, but archaeologicalevidence (mostly associated stone tools) suggests H. oresiensis lived at Liang Bua from atleast 190,000 to 50,000 years ago (recent dates published in Nature, March 2016). Thesedates make it one of the latest-surviving humans along with Neanderthals, Denisovans andour own species H. sapiens.

Their disappearance coincides with that of other local fauna such as the Stegodon, the giantmarabou stork and various vulture species. The loss was originally attributed to a volcaniceruption that occurred on Flores approximately 12,000 years ago but the recentlypublished dates nullify this suggestion. Instead, it is now considered possible that the arrivalof modern humans played a role. Although there is no evidence of modern humans inLiang Bua cave until 11,000 years ago, our species was moving through the region about50,000 years ago.

Important discoveries

A joint Australian-Indonesian team, looking for evidence of the early migration of Homosapiens from Asia to Australia, stumbled on the remains of a small human in the cave ofLiang Bua, Flores, in 2003. The discoverers (Peter Brown, Michael Morwood andcolleagues) argued that a variety of primitive and derived features identi ed the remains asthat of a new species. Descriptions of some of the remains and the new species designationwere published in October 2004.

The remains include a largely complete skeleton with skull (LB1) and parts of at leasteleven other individuals. These remains come from di erent levels and range in date from100,000




to 60,000 years old. An arm bone, from a deeper level and dating to about 74,000 yearsold, is provisionally assigned to H. oresiensis. A more accurate designation is di cult tomake as LB1 lacks an arm bone to make comparisons with.

Stone tools have been recovered from a number of levels and range in dates from 190,000to 50,000 years old.

As the remains are relatively young and unfossilised, researchers hoped to ndmitochondrial DNA. Initial efforts were unsuccessful, but the research continues.

Excavations from 2007 to 2014 used new dating techniques to understand the complexcave stratigraphy. The publication of the revised dates (in Nature, March 2016) led to areassessment of the causes of the species' extinction.

Key specimens

LB1 – type specimen discovered in September 2003. It is unfossilised. The remainsconsist of a fairly complete skull and partial skeleton including leg bones, parts of thepelvis, hands and feet, and some other fragments. It is assumed to belong to a femaleaged about 30 years old. She stood about 1 metre tall, had a brain volume of about380-420cc and weighed about 25 kilograms. The body was not deliberately buriedbut covered soon after death by fine sediments, when still partially fleshed. LB6 – a partial skeleton belonging to a shorter individual than LB1. It has a more V-shaped jaw and is assumed to be a child, possibly only 5 years old.

What the name means

The genus name Homo is the Latin word for ‘human’ or ‘man’. The species namefloresiensis recognises the island of Flores in Indonesia where the remains were found.

They are commonly referred to as the ‘hobbits’, after the Lord of the Rings characters, inreference to their small size and large feet.




Distribution

All remains come from the cave of Liang Bua on the island of Flores in Indonesia. Floreslies towards the eastern end of the Indonesian island chain.

Flores has always been separated from mainland Asia - even at low sea levels the water-crossing was at least 24 kilometres. It is known that other animals reached Flores byswimming or oating on debris. How or when H. oresiensis reached the island isunknown.

Relationships with other speciesAncestry

When rst discovered, it was suggested that H. oresiensis was possibly descended fromJavanese H. erectus. However, more detailed analysis of skeletal remains has uncoveredtraits more archaic than Asian H. erectus and more similar to australopithecines, H. habilisor the hominins from Dmanisi in Georgia (classi ed as Homo ergaster o r Homogeorgicus). Most scientists that accept H. oresiensis as a legitimate species now think itsancestor may have come from an early African dispersal by a primitive Homospecies similar in appearance to H. habilis or the Dmanisi hominins. This means that itshared a common ancestor with Asian H. erectus but was not descended from it. Cladisticanalysis supports the lack of a close relationship with H. erectus.

Unfortunately, no transitional forms, or the actual remains of H. erectus itself, have beenfound in Flores. However, stone tools that may have been made by H. erectus (or a similarspecies) were discovered on Flores. These date to 840,000 years ago, so indicate that ahominin species was probably living on the island at that time.

Whatever the origins of the ancestral population, it is accepted that thepopulation underwent long term isolation on the island and some insular dwar ng(although they were probably small to start with) which resulted in an endemic 'dwarf'species H. oresiensis. This is a common phenomenon seen in other mammals in similarenvironments.




Contemporaries

Modern humans arrived in Indonesia between 55,000 and 35,000 years ago, and mayhave interacted with H. floresiensis, although there is no evidence of this at Liang Bua.

Interestingly, local legends exist in Flores of the Ebu Gogo – small, hairy, cave dwellerssimilar in size to H. oresiensis. It is suggested that perhaps the hobbits survived longer inother parts of Flores to become the source of these stories.

A new species or a small Homo sapiens?

Doubts that the remains should be classi ed as a new species are voiced by a number ofscientists, some vehemently. They claim that the remains come from a modern humanwith some sort of physical disorder. The alternate suggestions include:

the remains are from a very small human that su ered from some type of disease thatcauses microcephaly, a developmental disorder of the brain that causes it to be muchsmaller than normal the remains are from a human with Laron syndrome, a disorder that results inpituitary dwarfism (published in 2007 by a team from Tel Aviv University, Israel) the remains are those of dwarfed Homo sapiens similar to the small-bodied humansthat inhabited the Micronesian island of Palau between 1400 and 3000 years ago.These people shared some features with the H. oresiensis specimens, but not all.Detailed analysis of the Palau specimens is unlikely to settle arguments over the statusof H. floresiensis but they do suggest that some of its unusual features could be due toenvironment rather than ancestry.

Many of those rejecting the new species status focus only on the remains of LB1, andignore the other remains that show many of the same characteristic features. In contrast, anumber of recent analyses of the skull, face, foot and wrist have con rmed the manyunusual




primitive features of H. oresiensis remains and stated that they are more similar toaustralopithecines. For instance:

a cladistic analysis done in 2009 supported H. oresiensis as a separate species(Journal of Human Evolution Online as of 4 August 2009) a study using 3D-morphometrics showed that the skull of LB1 di ers signi cantlyfrom all H. sapiens skulls, including those of small-bodied individuals andmicrocephalics, and is more similar to the skull of Asian Homo erectus (Baab &McNulty, Journal of Human Evolution, 2008) a team of experts created detailed maps of imprints left on LB1’s braincase andconcluded that the remains belonged to a new species. Comparisons of di erent partsof the brain showed it was nothing like a microcephalic's and is also di erent frommodern humans. The endocasts also revealed that parts of the frontal lobe and otherfeatures were consistent with higher cognitive processes. (Falk et al, PNAS, January29, 2007,) H. floresiensis wrist is almost indistinguishable from an African ape or early homininwrist and is nothing like those of modern humans or Neandertals. The distinctiveshapes of wrist bones form during pregnancy and as most pathologies and growthdisorders a ect the skeleton well after that, this demonstrates that the remains comefrom a new Homo species. (Matt Tocheri et al, Science 21 September 2007) studies on brain-size reduction in dwarf hippos from Madagascar revealed that brainsshrank to volumes well below predicted sizes. This refutes a key argument used bysceptics who claim the brains are too small for dwar ng alone to be the cause (hencethey cite microcephaly or similar disorders), (Weston & Lister, Nature, 7 May 2009)

Key physical featuresBody size and shape

very small stature of about 1 metre (the remains of 5 individuals were used for thisaverage), which is less than the average for short populations of humans such aspygmies (who average about 1.4-1.5 m tall)

the wide pelvis and hunched shoulders give it a di erent body shape compared withH. sapiens




Brain

combination of features not seen in other hominin species has features that are not found in H. sapiens, particularly in the temporal and frontallobes small brains averaging 380cc, about the size of a chimpanzee. This suggests there wasactive selection for a small brain size, possibly related to the reduced energyrequirements of small brains. enlarged Broadmann area 10, an area of the brain that appears to help with complexcognitive activities

Skull

cranial shape is long and low and closer to that of H. erectus than H. sapiens receding and small forehead thick bones within the range of H. erectus and H. sapiens flat face brow ridges over each eye that do not form a continuous brow ridge as in IndonesianH. erectus narrow nose

Jaws and teeth

lacks the bony point on the chin found in modern humans relatively large jaw and teeth that resemble H. erectus but with more primitivefeatures premolar roots different from H. sapiens small post-canine and canine teeth parabolic or V-shaped dental arcade typical of Homo bony shelf at the front of the lower jaw which is a primitive feature not seen in H.erectus

Limbs and pelvis

bones and joints of the arm, shoulder and the lower limbs suggest that H. oresiensiswas more similar to early humans than modern humans




characteristic bipedal foot that includes a big toe aligned with other toes and a lockingmechanism on the middle of the foot to help stiffen the arch after heel lift occurs several primitive features include a relatively long foot for its body size (70% as long asthe thigh bone, compared with 55% for modern humans), a at arch lacking thespring-like mechanism used to store and release energy during running, and a shortbig toe. These features are similar to ancient hominins such as H. habilis (OH8) andaustralopithecines and suggest the gait was di erent from and less e cient thanmodern humans. unusual low twist in the upper arm bone wide leg bones compared to the length relatively short and curved clavicle shape of the shoulder blade resulted in the shoulder being moved forwards slightly asif hunched wrist bones di er signi cantly from the those of modern humans and are moresimilar to African apes or australopithecines. They lack features that evolved with theancestors of modern humans at least about 800,000 years ago. In particular, thetrapezoid bone is pyramidal in form, whereas modern humans have a boot-shapedtrapezoid. primitive ared ilium blades in the pelvis, similar to australopithecines, and femaleshave wider pelvises than H. sapiens females relatively long arms

LifestyleCultureTools

Stone tools were found in a number of di erent layers dating from 190,000 to 50,000years ago. Tools include simple akes, points, perforators, blades and microblades whichwere possibly hafted as barbs. Some were found with the remains of LB1, but most camefrom the same location as the remains of the extinct pygmy elephant Stegodon. Thissuggests that




H. oresiensis was hunting these small elephants. Stone tools produced by heavierpercussion were also recovered from layers not associated with H. oresiensis occupation.These tools date to about 102,000 years ago. The makers are unidentified.

There has been some speculation that the stone tools associated with H. oresiensis wereactually made by H. sapiens. The basis for this is purely the belief that humans with suchsmall brains couldn’t make such sophisticated stone tools – there is no other evidence insupport of this. However, those studying the tools claim they are not as sophisticated asthey appear and regard them as ‘simple’.

Analysis of the residues and polish on some of the tools revealed they were used forworking wood and brous materials, perhaps to make spear shafts or items such as traps.Cut marks on the Stegodon bones also suggest some of the tools were used to process meat.

Precursors to this tool kit may come from earlier sites on Flores. Tools excavated fromMata Menge (about 50km from Liang Bua) in 2004-5 are at least 700,000 years old, andthose from the Soa Basin date to about 880,000 years old. Tool kits from both sites showsome similarities and technological continuity with those found in Liang Bua cave. Theidentity of the makers is unknown, but they could possibly be ancestral to H. floresiensis.

Fire

There is evidence of the use of re in Liang Bua cave. The remains of numerous juvenileStegodon have charred bones, possibly indicating that H. oresiensis was able to controlfire for cooking.

Other

There are no traces of pigments, ornaments or deliberate burials in the layers associatedwith H. oresiensis – all of which characterise the modern human levels from the upperparts of the cave.




Environment and diet

Flores is a heavily forested tropical island with mountain peaks reaching over 2000 metres.The environment during H. floresiensis' time would have been similar. The nature of theirenvironment and the limited food sources typical of such islands provides strong clues tothe evolution of H. oresiensis. When a small population becomes separated, changes canoccur very quickly. This particular environment favours reduced energy requirementswith dwar ng a response to this. Several dwarf species, including Stegodon, have beenrecovered on Flores and other small islands.

This species shared the island with pygmy elephants Stegodon, giant rats and large lizardslike Komodo dragons. Evidence of cut marks on the Stegodon bones from Liang Bua caveshow that H. floresiensis was at least hunting and eating this animal.

Fran Dorey , Exhibition Project Coordinator Last Updated: 31 March 2016


https://australianmuseum.net.au/staff/fran-dorey


(03) Homo floresiensis essay | Becoming Human

Homo floresiensis

Homo oresiensis is a small-bodied hominin species that is dated to between 95,000 and17,000 years ago. Known from a single cave on the island of Flores in eastern Indonesia,H. oresiensis displays a surprising combination of cranial features that resemble those ofHomo erectus and Homo sapiens, postcranial features (features of the limb and trunk) thatmost closely resemble those of species in the genus Australopithecus, and a stone tooltechnology linked to those often associated with H. sapiens. If the fossils assigned thisspecies do not represent a population of pathological H. sapiens, as some researchers haveargued, they represent a new hominin species and suggest H. sapiens shared the planetwith another species much more recently than previously believed.

The cranial material of H. oresiensis comprise teeth and mandibles (lower jaws) frommultiple individuals and a single, nearly complete skull. The skull and teeth share somederived features (features not found in the common ancestor) shared with H. erectus andH. sapiens. The face is small, speci cally in facial height (a measurement between thebrow and the upper teeth) and exhibits reduced prognathism (how far the upper and lowerjaws project out from the face) compared to australopith species. The H. floresiensismolars (the teeth at the back of the jaw) and canines are also relatively small, similar to thecondition found in H. erectus and H. sapiens.. These Indonesian fossils also possessesmany primitive features similar to earlier hominins. For example, the brain is very small(380 to 420 cubic centimeters) and is more similar to apes and species in the genusAustralopithecus. The mandibles and premolars (bicuspid teeth), which represent at least8 partial individuals, share distinctive primitive traits with both Australopithecus andHomo habilis. The premolars are asymmetrical and elongated with complex tooth roots. The mandibles are relatively robust and large in size; yet lack a chin (central part of thelower jaw that protrudes out from the face, found only in H. sapiens mandibles).

Homo floresiensis essay | Becoming Human

http://www.becominghuman.org/node/homo-floresiensis-essay


In contrast to the cranium, where only one complete skull was found, postcranial remainsfrom multiple individuals have been recovered. The shoulder joint is cranially oriented(toward the skull) and the clavicle (collar bone) is short and very curved, suggesting theshoulder was high on the torso, as seen in apes and species in the genus Australopithecus. Other aspects of the postcranial skeleton of these Flores nds that are shared withAustralopiths include relatively long arms, ared pelves (plural of “pelvis”; pelvic bladesthat extend beyond the hip joint) and relatively short legs. Moreover, the hand and wristo f H. oresiensis seem to be more primitive than even the earliest representatives of thegenus Homo (H. habilis) and closely resemble the shape found in Australopiths. Theprimitive morphology (size and shape) of the H. floresiensis hand and wrist suggests thisspecies lacked the ability to precisely manipulate items with their hands. Interestingly, thefoot of this species is similar to H. sapiens in some respects: the big toe is aligned with theother toes and the bones are thick and robust. Nevertheless, the overall foot morphologyexhibits a generally primitive pattern. For instance, the foot is approximately 20centimeters in length, much longer than any H. sapiens foot from an individual ofcomparable height to the short statured Homo floresiensis individuals, resembling moreclosely the length of chimpanzee and australopith foot. The toes exhibit primitive featuressuch as long and curved lateral toes (the four toes to the outside of the feet; all but thehallux or big toe) and the hallux is quite short in comparison to that possessed by H.sapiens . The H. oresiemsis foot also seems to lack the longitudinal arch that ischaracteristic of H. erectus and H. sapiens.

Some researchers argue the Flores remains are those of a diseased individual of our ownspecies and have suggested a number of pathologies that could explain the mosaic offeatures exhibited by these remains. Pathologies that have been suggested include variousforms of microcephaly (a class of genetic disorders in which the head and brain areabnormally small) and growth disorders, such as hypothyroidism (a condition in which thethyroid gland does not produce enough hormones that regulate the body’smetabolism) and Laron’s Syndrome (a genetic disorder in which the body does not processgrowth hormones normally). Detailed comparisons of the H. oresiensis material,however,




seem to provide little support for these hypotheses because measurements of the remainsfall outside of modern H. sapiens ranges of variation, even when compared to those withthe aforementioned pathological conditions. Moreover, no pathological syndrome seemsto adequately explain the suite of features exhibited by H. floresiensis. The fact that all ofthe individuals found at the cave site exhibit similar cranial and postcranial morphologycasts further doubt on the hypothesis that the H. oresiensis remains are those ofpathological H. sapiens, as it is unlikely multiple individuals would show signs of relativelyrare diseases.

Considerable attention has also been paid to the evolutionary history of Homofloresiensis—e.g., how did it get to Indonesia and of which previously known homininspecies is it a descendant? Some researchers have suggested H . floresiensis represents adwarfed descendent of Asian H. erectus populations. However, there is no evidence forlarger-bodied (non-dwarfed) ancestors of H. oresiensis on the island, making thishypothesis di cult to test. This fact and H. oresiensis’ primitive anatomy (brain size,limbs, pelvis, hands and wrist) has led some anthropologists to postulate the remains areevidence of a pre-Homo erectus migration of an earlier species in the genus Homo or aspecies in the genus Australopithecis. Another hypothesis is that H. oresiensis descendedfrom an earlier, more primitive type of H. erectus (such as that represented by H. erectusremains from the site of Dmanisi in the Republic of Georgia; see essay on H. erectus). Most researchers agree the current anatomical evidence shows that H. oresiensis is inmany ways more similar to early Homo species (e.g., Homo habilis) than to later Homospecies. This observation supports the idea that the ancestors of H. oresiensis left theAfrican continent before the evolution of H. erectus, but the precise origins of this speciesremain unknown.

The stone artifact assemblages found in association with the skeletal remains of H.oresiensis are dense and demonstrate continuity in production method and tool type

throughout the cave deposits. There are a large number of bifacial (struck on both sides)and radial (struck from the outer edge towards the center) cores (rocks from which pieces[ akes] are chipped to produce tools), similar to the Oldowan stone artifact assemblages inEast Africa. More complex tools—e.g., points (sharpened, pointed tools), perforators (tools




designed to make holes or incisions), blades ( ake that is at least twice as long as it is wide)and microblades (blades less than 10 mm, often components of composite tooltechnology)— have also been recovered. The combination of primitive, Oldowan-likecore technology with more advanced tool assemblages is quite uncommon in thearchaeological record and make interpretations of the stone tool assemblages found inassociation with H. oresiensis di cult. Some researchers have questioned whether H.floresiensis had the cognitive capacity to make the more complex tools, citing its smallbrain size. However, no skeletal remains of H. sapiens have been found at sites bearingHomo oresiensis skeletal material and artifacts commonly associated with the symbolicbehaviors of Homo sapiens (e.g., personal ornaments, pigments, and formal disposal of thedead) are also absent, suggesting that H. floresiensis was the manufacturer of all of the toolsfound at this site.

Researchers have recently recovered stone tools from a site close to the cave on FloresIsland. This site dates to roughly 1.02 million years ago and therefore provides a newminimum age for hominin inhabitation of the island. The artifacts found at this site aresimilar to those found at the original site; they are small akes and both bifacially andradially struck cores. However, the absence of skeletal remains at this second site disallowsthe establishment of a direct link between H. oresiensis (or any other hominin species)and this stone tool assemblage.

The reconstructed paleoenvironment for H. oresiensis spans three cycles of glacial (cold,dry periods) to interglacial (warm episodes between glacial intervals) changeovers. Theearlier cave sediments suggest a wet, rich surrounding environment with dense forests. However, a shift is indicated after 39,000 years ago and Flores begins a transition to morearid conditions. There is a reduction in rainfall and forest cover, as well as thedevelopment of widespread grasslands. The environment changed yet again 17,000 yearsago and became gradually more wet. The appearance of parrots in the assemblage suggeststhat the local ora was changing into a more closed canopy forest, similar to present dayenvironments.



(01) H. neanderthalensis | The Smithsonian Institution's Human Origins

Homo neanderthalensis

Nickname: Nickname: Neanderthal

Where Lived: Where Lived: Europe and southwestern tocentral Asia

When Lived: When Lived: About 400,000 - 40,000 years ago

Neanderthals (the ‘th’ pronounced as ‘t’) are our closest extinct human relative. Somede ning features of their skulls include the large middle part of the face, angled cheekbones, and a huge nose for humidifying and warming cold, dry air. Their bodies wereshorter and stockier than ours, another adaptation to living in cold environments. Buttheir brains were just as large as ours and often larger - proportional to their brawnierbodies.

Neanderthals made and used a diverse set of sophisticated tools, controlled re, lived inshelters, made and wore clothing, were skilled hunters of large animals and also ate plantfoods, and occasionally made symbolic or ornamental objects. There is evidence thatNeanderthals deliberately buried their dead and occasionally even marked their graves witho erings, such as owers. No other primates, and no earlier human species, had everpracticed this sophisticated and symbolic behavior.

DNA has been recovered from more than a dozen Neanderthal fossils, all from Europe;the Neanderthal Genome Project is one of the exciting new areas of human originsresearch.

Year of Discovery: Year of Discovery: 1829

Homo neanderthalensis | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/evidence/human-fossils/species/homo-neanderthalensis


History of Discovery: History of Discovery:

Neanderthal 1 was the rst specimen to be recognized as an early human fossil. When itwas discovered in 1856 in Germany, scientists had never seen a specimen like it: the ovalshaped skull with a low, receding forehead and distinct browridges, the thick, strong bones.In 1864, it became the rst fossil hominin species to be named. Geologist William Kingsuggested the name Homo neanderthalensis (Johanson and Edgar, 2006), after these fossilsfound in the Feldhofer Cave of the Neander Valley in Germany ( tal—a modern form ofthal—means “valley” in German). Several years after Neanderthal 1 was discovered,scientists realized that prior fossil discoveries—in 1829 at Engis, Belgium, and in 1848 atForbes Quarry, Gibraltar—were also Neanderthals. Even though they weren’t recognizedat the time, these two earlier discoveries were actually the rst early human fossils everfound.

Height: Height: Males: average 5 ft 5 in (164 cm); Females: average 5 ft 1 in (155 cm)

Weight: Weight: Males: average 143 lbs (65 kg); Females: average 119 lbs (54 kg)

We don’t know everything about our early ancestors. But scientists are constantly in theeld and the laboratory, excavating new areas and conducting analyses with

groundbreaking technology, continually lling in some of the gaps about ourunderstanding of human evolution.

Below are some of the still unanswered questions about H. neanderthalensis that may bebetter answered with future discoveries:

Will more studies of Neanderthal DNA help us identify what is unique about themodern human genome compared with our closest extinct relatives, the Neanderthals?

Is there a close correlation between climate change and the extinction of theNeanderthals, or was competition with modern humans the most important factor?

What was the relative contribution of animal and plant sources to the averageNeanderthal's diet?




Were Neanderthals routinely symbolic (e.g. making ornamental or decorative objects,burying the dead), or did this just occur in specific populations? If the latter is the case, whydid those populations exhibit these behaviors?

What was the relationship between Neanderthals and the "Denisovans", a population ofearly humans known mainly from DNA, which overlapped with Neanderthals in timeand space in Asia?

First paper:

King, W., 1864. The reputed fossil man of the Neanderthal. Quarterly Review of Science1, 88-97.

Other recommended readings:

Trinkhaus, E., 1985. Pathology and the posture of the La Chappelle-aux-SaintsNeanderthal. American Journal of Physical Anthropology 67, 19-41.

Trinkaus, E., Shipman, P., 1993. The Neanderthals: Changing the Image of Mankind.Knopf: New York.

Berger, T., Trinkaus, E., 1995. Patterns of trauma among the Neandertals. Journal ofArchaeological Science 22, 841-852.

Schmitt, D., Churchill, S., 2003. Experimental evidence concerning spear use inNeandertals and early modern humans. Journal of Archaeological Science 30, 103-114.

Delson, E., Harvati, K., 2006. Return of the last Neanderthal. Nature 443, 762-763.

Lalueza-Fox, C., Römpler, H., Caramelli, D., Stäubert, C., Catalano, G., Hughes, D.,Rohland, N., Pilli, E., Longo, L., Condemi, S., de la Rasilla, M., Fortea, J., Rosas, A.,Stoneking, M., Schöneberg, T., Bertranpetit, J., Hofreiter, M., 2007. A Melanocortin 1Receptor Allele Suggests Varying Pigmentation Among Neanderthals. Science 318, 1453-1455.



Homo neanderthalensis | The SmithsonianInstitution's Human Origins Program

Stringer, C.B., Finlayson, J.C., Barton, R.N.E, Fernández-Jalvo, Y., Cáceres, I., Sabin,R.C., Rhodes, E.J., Currant, A.P., Rodríguez-Vidal, J., Giles-Pacheco, F., Riquelme-Cantal, J.A., 2008. Neanderthal exploitation of marine mammals in Gibraltar.Proceedings of the National Academy of Sciences USA 105, 14319–14324.

Shipman, P., 2008. Separating "us" from "them": Neanderthal and modern humanbehavior. Proceedings of the National Academy of Sciences USA 105, 14241-14242.

How They Survived: How They Survived:

Compared to early humans living in tropical Africa, with more abundant edible plantfoods available year-round, the number of plant foods Neanderthals could eat would havedropped signi cantly during the winter of colder climates, forcing Neanderthals to exploitother food options like meat more heavily. There is evidence that Neanderthals werespecialized seasonal hunters, eating animals were available at the time (i.e. reindeer in thewinter and red deer in the summer). Scientists have clear evidence of Neanderthal huntingfrom uncovering sharp wooden spears and large numbers of big game animal remainswere hunted and butchered by Neanderthals. There is also evidence from Gibraltar thatwhen they lived in coastal areas, they exploited marine resources such as mollusks, seals,dolphins and sh. Isotopic chemical analyses of Neanderthal bones also tell scientists theaverage Neanderthal’s diet consisted of a lot of meat. Scientists have also found plaque onthe remains of molar teeth containing starch grains—concrete evidence that Neanderthalsate plants. The Mousterian stone tool industry of Neanderthals is characterized bysophisticated ake tools that were detached from a prepared stone core. This innovativetechnique allowed akes of predetermined shape to be removed and fashioned into toolsfrom a single suitable stone. This technology di ers from earlier ‘core tool’ traditions, suchas the Acheulean tradition of Homo erectus. Acheulean tools worked from a suitable stonethat was chipped down to tool form by the removal of akes o the surface. Neanderthalsused tools for activities like hunting and sewing. Left-right arm asymmetry indicates thatthey hunted with thrusting (rather than throwing) spears that allowed them to kill largeanimals from a safe distance. Neanderthal bones have a high frequency of fractures, which(along with their distribution) are similar to injuries among professional rodeo riders who




regularly interact with large, dangerous animals. Scientists have also recovered scrapers andawls (larger stone or bone versions of the sewing needle that modern humans use today)associated with animal bones at Neanderthal sites. A Neanderthal would probably haveused a scraper to rst clean the animal hide, and then used an awl to poke holes in it, andfinally use strips of animal tissue to lace together a loose-fitting garment

Neanderthals were the rst early humans to wear clothing, but it is only with modernhumans that scientists nd evidence of the manufacture and use of bone sewing needles tosew together tighter fitting clothing. Neanderthals also controlled fire, lived in shelters, andoccasionally made symbolic or ornamental objects. There is evidence that Neanderthalsdeliberately buried their dead and occasionally even marked their graves with o erings,such as owers. No other primates, and no earlier human species, had ever practiced thissophisticated and symbolic behavior. This may be one of the reasons that the Neanderthalfossil record is so rich compared to some earlier human species; being buried greatlyincreases the chance of becoming a fossil!

Evolutionary Tree Information: Evolutionary Tree Information:

Both fossil and genetic evidence indicate that Neanderthals and modern humans (Homosapiens) evolved from a common ancestor between 500,000 and 200,000 years ago.Neanderthals and modern humans belong to the same genus (Homo) and inhabited thesame geographic areas in Asia for 30,000–50,000 years; genetic evidence indicate whilethey may have interbred with non-African modern humans, they are separate branches ofthe human family tree (separate species).




In fact, Neanderthals and modern humans may have had little direct interaction for tens ofthousands of years until during one very cold period, modern humans spread acrossEurope. Their presence may have prevented Neanderthals from expanding back into areasthey once favored and served as a catalyst for the Neanderthal’s impending extinction.Over just a few thousand years after modern humans moved into Europe, Neanderthalnumbers dwindled to the point of extinction. All traces of Neanderthals disappeared byabout 40,000 years ago. The most recently dated Neanderthal fossils come from westernEurope, which was likely where the last population of this early human species existed.

Neanderthals have contributed approximately 1-4% of the genomes of non-Africanmodern humans, although a modern human who lived about 40,000 years ago has beenfound to have between 6-9% Neanderthal DNA (Fu et al 2015). The evidence we have ofNeanderthal-modern human interbreeding sheds light on the expansion of modernhumans out of Africa. These new discoveries refute many previous hypotheses in whichanatomically modern humans replaced archaic hominins, like Neanderthals, without anyinterbreeding. However, even with some interbreeding between modern humans andnow-extinct hominins, most of our genome still derives from Africa. Neanderthals couldnot have contributed to modern African peoples’ genomes because Neanderthals evolvedand lived exclusively in Eurasia and therefore could not have bred with the humans livingin Africa at that time.

For many years, the only evidence of human-Neanderthal hybridization existed withinmodern human genes. However, in 2016 researchers published a new set of NeanderthalDNA sequences from Altai Cave in Siberia, as well as from Spain and Croatia, that showevidence of human-Neanderthal interbreeding as far back as 100,000 years ago -- fartherback than many previous estimates of humans’ migration out of Africa (Kuhlwilm et al2016). Their ndings are the rst to show human gene ow into the Neanderthal genomeas opposed to Neanderthal DNA into the human genome. This data tells us that not onlywere human-Neanderthal interbreeding events more frequent than previously thought,but also that an early migration of humans did in fact leave Africa before the populationthat survived and gave rise to all contemporary non-African modern humans.



Ancient DNA and Neanderthals | The SmithsonianInstitution's Human Origins Program

We previously mentioned the lack of genetic contributions by Neanderthals into themodern human mtDNA gene pool. As we have shown that Neanderthal-humaninterbreeding did occur, why wouldn’t we nd their DNA in our mtDNA as well as ournuclear DNA? There are several potential explanations for this. It is possible that therewere at one point modern humans who possessed the Neanderthal mtDNA, but that theirlineages died out. It is also highly possible that Neanderthals did not contribute tothe mtDNA genome by virtue of the nature of human-Neanderthal admixture. Whilewe know that humans and Neanderthals bred, we have no way of knowing what thepossible social or cultural contexts for such breeding would have been.

Because mtDNA is passed down exclusively from mother to o spring, if Neanderthalmales were the only ones contributing to the human genome, their contributions wouldnot be present in the mtDNA line. It is also possible that while interbreeding betweenNeanderthal males and human females could have produced fertile o spring,interbreeding between Neanderthal females and modern human males might not haveproduced fertile o spring, which would mean that the Neanderthal mtDNA could not bepassed down. Finally, it is possible that modern humans do carry at least one mtDNAlineage that Neanderthals contributed to our genome, but that we have not yet sequencedthat lineage in either modern humans or in Neanderthals. Any of these explanations couldunderlie the lack of Neanderthal mtDNA in modern human populations.

Fast Facts:Neanderthals have contributed between 1-4% of the DNA of humans of Eurasian descent

Neanderthals have not contributed to the genome of African modern human populationsbecause they never lived there and could not have interbred with the ancestors of thosepopulations

While we don’t have evidence of Neanderthal mtDNA in the modern human gene pool,there are several possible explanations for this

Ancient DNA and Neanderthals | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/evidence/genetics/ancient-dna-and-neanderthals/interbreeding

https://australianmuseum.net.au/image/Gibraltar-Skull-Homo-neanderthalensis-front/

(02) Homo neanderthalensis – The Neanderthals

Neanderthals co-existed with modern humans for long periods of time before eventuallybecoming extinct about 28,000 years ago.

Gibraltar Skull Homo neanderthalensis front Photographer: Carl Bento © Australian Museum

Homo neanderthalensis – The Neanderthals

https://australianmuseum.net.au/homo-neanderthalensis


The unfortunate stereotype of these people as dim-witted and brutish cavemen still lingersin popular ideology but detailed scienti c research has revealed a more accurate picture.Neanderthals were advanced humans, capable of intelligent thought processes and wereable to adapt to and survive in some of the harshest environments known to humans.

Background on discoveryAge

This species lived between 28,000 and 300,000 years ago

early Homo neanderthalensis from about 300,000 years ago classic Homo neanderthalensis from about 130,000 years ago late Homo neanderthalensis from about 45,000 years ago.

Important fossil discoveries

The rst Neanderthal fossil was found in 1829, but it was not recognised as a possiblehuman ancestor until more fossils were discovered during the second half of the 19thcentury. Since then, thousands of fossils representing the remains of many hundreds ofNeanderthal individuals have been recovered from sites across Europe and the Middle East.These include babies, children and adults up to about 40 years of age. As a result, more isknown about this human ancestor than about any other.

Key specimens:

Le Moustier – a 45,000-year-old skull discovered in Le Moustier, France. Thedistinctive features of Neanderthals are already apparent in this adolescent individual.This shows that these characteristics were genetic and not developed during anindividual’s lifetime. Shanidar 1 – upper jaw with teeth. The front teeth of Neanderthals often show heavywear, a characteristic that is even found in young Neanderthals. It is probable thatthey used their teeth as a kind of vice to help them hold animal skins or other objectsas they worked.




La Ferrassie 1 – a 50,000-year-old skull discovered in 1909 in La Ferrassie, France.This skull of an elderly male has the features associated with ‘classic’ EuropeanNeanderthals. Amud 1 – a 45,000-year-old skull discovered in1961 by Hisashi Suzuki in Amud,Israel. This individual was more than 180 centimetres tall and had the largest brain ofany fossil human (1740 cubic centimetres). Neanderthals probably migrated to theMiddle East during times of harsh European winters. These individuals had lessrobust features than their European counterparts. Maba – a partial skull classifed as Hom o sp. (species uncertain) and discoveredin Maba, China. This partial skull, dated to about 120,000 – 140,000 years old,shows remarkable similarities to European Neanderthals and its discovery in southernChina suggests the possibility that Neanderthals travelled further east than oncethought. More fossil evidence from Asia is needed to understand the signi cance ofthis specimen. La Chapelle-aux-Saints – a 50,000-year-old skull discovered in 1908 in La Chapelle-aux-Saints, France. This male individual had lost most of his teeth and his skeletonshowed evidence of major injuries and disease including a healed broken hip, andarthritis of the lower neck, back, hip and shoulders. He survived for quite some timewith these complaints, which indicates that these people cared for the sick and elderly. Neanderthal 1 – a 45,000-year-old skullcap discovered in 1856 in Feldhofer Grotto,Neander Valley, Germany. This is the ‘type specimen’ or o cial representative of thisspecies.

Kebara 2 – 60,000-year-old partial skeleton discovered in 1983 in Kebara cave, Israel.This relatively complete skeleton belonged to an adult male. It was deliberatelyburied but as no grave goods were found it is di cult to infer any ritualisticbehaviour.




Lagar Velho – a 24,000-year-old skeleton of a Homo sapiens boy discovered in 1998in Abrigo do Lagar Velho, central western Portugal. This specimen has beendescribed by its discoverers (and particularly Eric Trinkhaus) as a Neanderthal-Hom osapiens hybrid. This interpretation was based on knee and leg proportions but as thehead, pelvis and forearms are decidedly human it is more likely that the robustness is aclimatic adaptation (see Tattersal and Schwartz). Comparisons to other humans ofthis period are di cult due to lack of knowledge on variations within childpopulations.

What the name means

Homo, is a Latin word meaning ‘human’ or ‘man’. The word neanderthalensis is based onthe location where the rst major specimen was discovered in 1856 – the Neander Valleyin Germany. The German word for valley is ‘Tal’ although in the 1800s it was spelt ‘Thal’.Homo neanderthalensis therefore means ‘Human from the Neander Valley’.

Some people refer to this species as the Neandertals (with no 'h') to re ect the modernGerman spelling rather than the original spelling, Neanderthal, used to define the species.

Distribution

Remains of this species have been found scattered across Europe and the Middle East. Theeastern-most occurrence of a Neanderthal may be represented by a fossil skull from Chinaknown as ‘Maba’.

A study published in 2009 con rms the presence of three separate sub-groups ofNeanderthals, between which slight di erences could be observed, and suggests theexistence of a fourth group in western Asia. The study analysed the genetic variability, andmodelled di erent scenarios, based on the genetic structure of the maternally transmittedmitochondrial DNA (mtDNA). The study was possible thanks to the publication, since1997, of 15 mtDNA sequences from 12 Neanderthals. According to the study, the size ofthe Neanderthal population was not constant over time and a certain amount of migrationoccurred among the sub-groups.




Relationships with other speciesWhile we are closely related to the Neanderthals, they are not our direct ancestors.Evidence from the fossil record and genetic data shows they are a distinct species thatdeveloped as a side branch in our family tree. Some European Homo heidelbergensis fossilswere showing early Neanderthal-like features by about 300,000 years ago and it is likelythat Neanderthals evolved in Europe from this species.

The name Homo sapiens neanderthalensis was once common when Neanderthals wereconsidered to be members of our own species, Homo sapiens. This view and name are no-longer favoured.

Interbreeding with modern humans?

Groundbreaking analysis of the Neanderthal genome (nuclear DNA and genes) publishedin 2010 shows that modern humans and Neanderthals did interbreed, although on a verylimited scale. Researchers compared the genomes of ve modern humans with theNeanderthal, discovering that Europeans and Asians share about 1-4% of their DNA withNeanderthals and Africans none. This suggests that modern humans bred withNeanderthals after moderns left Africa but before they spread to Asia and Europe. Themost likely location is the Levant, where both species co-existed for thousands of years atvarious times between 50-90,000 years ago. Interestingly, the data doesn't support wide-scale interbreeding between the species in Europe, where it would have been most likelygiven their close proximity. Researchers are now questioning why interbreeding occurredon such a low scale, given that it was biologically possible. The answer may lie in culturaldifferences.

Sharing Europe with the Denisovians?

Did the Neanderthals also live alongside another human species in Europe? An interestingcase making headlines in 2010 was the discovery of a nger bone and tooth from Denisovacave in Russia. The bones were found in 2008 and date to about 30,000-50,000 years old.Mitochondrial DNA (mtDNA) was extracted from the remains, and then sequenced. Theresult was that the mtDNA did not match either modern human or Neanderthal mtDNA.




Little else could be gleaned from these studies so scientists started work on extractingnuclear DNA. This produced far more information. The 'Denisovians', as they have beennicknamed, were more closely related to Neanderthals than modern humans. This suggeststhe Neanderthals and 'Denisovans' shared a common ancestor after modern humans andNeanderthals split. Perhaps this ancestor left Africa half a million years ago with theNeanderthals spreading west to the Near East and Europe while the Denisovans headedeast. However, this does not necessarily mean they are a 'new' species as they may bealready known from fossils that have no DNA record to compare, such as Homoheidelbergensis or H. antecessor. (See Nature, December 2010)

Key physical featuresNeanderthals are recognisably human but have distinctive facial features and a stocky buildthat were evolutionary adaptations to cold, dry environments.

Body size and shape

Neanderthals were generally shorter and had more robust skeletons and muscularbodies than modern humans males averaged about 168 centimetres in height while females were slightly shorter at156 centimetres.

Brain

brain size was larger than the average modern human brain and averaged 1500 cubiccentimetres. This is expected, as Neanderthals were generally heavier and more muscularthan modern humans. People that live in cold climates also tend to have larger brains thanthose living in warm climates.

Skull

distinctive skull shape that was long and low, with a rounded brain case back of the skull had a bulge called the occipital bun and a depression (the suprainiacfossa) for the attachment of strong neck muscles




thick but rounded brow ridge lay under a relatively flat and receding forehead mid-face region showed a characteristic forward projection (this resulted in a face thatlooked like it had been ‘pulled’ forward by the nose) orbits (eye sockets) were large and rounded nose was broad and very large

Jaws and teeth

jaws were larger and more robust than those of modern humans and had a gap calledthe retromolar space, behind the third molars (wisdom teeth) at the back of the jaw. jaw lacked the projecting bony chin that is found in Homo sapiens. teeth were larger than those of modern humans.

Limbs and pelvis

limb bones were thick and had large joints which indicates they had strongly muscledarms and legs shin bones and forearms tended to be shorter than those of modern humans. Theseproportions are typical for people living in cold climates. pelvis was wider from side to side than in modern humans and this may have slightlyaffected their posture

DNA and biomolecular studies

Neanderthals are our only ancestors to have had studies performed on their DNAand other biomolecules. Although numerous studies have been undertaken since the

rst was published in 1997 (on mitochondrial DNA), the most signi cant is thepublication in 2009 of the rough draft of the Neanderthal genome. Other key findings on from a variety of studies include the discovery of: a gene for redhair and fair skin (2007): the FOXP2 gene, related to language ability, that was thesame as modern humans; type O blood in two males from Spain (2008)




LifestyleCulture

Evidence shows that Neanderthals had a complex culture although they did not behave inthe same ways as the early modern humans who lived at the same time. Scholars debate thedegree of symbolic behaviour shown by Neanderthals as nds of art and adornment arerare, particularly when compared to their modern human contemporaries who werecreating signi cant amounts of cave paintings, portable art and jewellery. Some researchersbelieve they lacked the cognitive skills to create art and symbols and, in fact, copied from ortraded with modern humans rather than create their own artefacts. However, otherssuggest the scarcity may have been due to social and demographic factors.

Tools

The Neanderthals had a reasonably advanced tool kit classi ed as Mode 3 technology thatwas also used by early members of our own species, Homo sapiens. This was also knownas the Mousterian, named after the site of Le Moustier. At the end of their long history inEurope, they began manufacturing a more re ned toolkit (known as theChatelperronian), similar to the blade tools of Homo sapiens. This occurred at about thesame time as modern humans entered Europe. Many archaeologists think that theNeanderthals were attempting to copy the types of tools that they observed modernhumans making. Alternatively, they may have obtained these tools by trading with themodern humans.

Fire, shelter and clothing

The Neanderthals built hearths and were able to control re for warmth, cooking andprotection. They were known to wear animal hides, especially in cooler areas. However,there is no physical evidence that Neanderthal clothing was sewed together, and it mayhave simply been wrapped around the body and tied.

Caves were often used as shelters but open air shelters were also constructed.




Art and decoration

Neanderthals left behind no known symbolic art and only limited evidence for bodydecoration. One of few decorative items found at a Neanderthal site is a pendant fromArcy-sur-Cure in France, found amongst bone tools and other artefacts that wereattributed to a culture known as Chatelperronian (which most researchers considerNeanderthal). However, redating of the site's layers in 2010 suggest contaminationoccurred between layers and that the artefact may have been made by modern humans, asthey also occupied this site in later times. There is only one other undisputedChatelperronian site that has yielded personal ornaments, and even these may have beenobtained by trade with modern humans ( Homo sapiens), or been made in imitation ofartefacts made by modern humans.

In 2010 researchers uncovered artefacts at two sites in Spain - Anton rock shelter andAviones cave - that provide indirect evidence of symbolic art. The former held naturally-perforated scallop shells painted with orange pigments and the latter a cockleshell that mayhave been used as a paint container as it had residue of red and black pigments. The Avione

nds date to between 45-50,000 years ago, which is before modern humans arrived inEurope so could not have been copied from them.

Burials

The dead were often buried, although there is no conclusive evidence for any ritualisticbehaviour. However, at some sites, objects have been uncovered that may represent gravegoods.

Environment and diet

This species occupied a range of environments across Europe and the Middle East and livedthrough a period of changing climatic conditions. Ice Ages in Europe were interspersedwith warmer periods but by 110,000 years ago average temperatures were on the declineand full glacial conditions had appeared by 40,000 years ago.




There is evidence that the Neanderthals hunted big game and chemical analysis of theirfossils shows that they ate signi cant amounts of meat supplemented with vegetation.Despite this mixed diet, nearly half of the Neanderthal skeletons studied show the e ects ofa diet deficient in nutrients.

Researchers have long debated whether Neanderthals also included human meat in theirdiets. It is not always easy to determine if cut marks on human bones are dueto cannabilism, some other practice or even animal teeth, but in recent years new evidencehas emerged that suggests some Neanderthals may indeed have been cannibals onoccasions.

At the site of Krapina Cave in Croatia, over 800 Neanderthal bones show evidence ofcut marks and hammerstone fragments. The marrow-rich bones are missing and themarrow-poor bones are all in tact. Some argue that the evidence is inconclusive as thefragmentation of bones may have been caused by cave-ins and the bone cuts aredi erent to the marks seen on reindeer bones. They claim the cut marks could befrom secondary burial practises. Bones from Abri Moula in France show cut marks typical of butchery rather thansimple ritual de eshing. The marks were also like those on the bones of roe deer,assumed to be food, found in the same shelter. The cave of El Sidron in Spain yielded hundreds of Neanderthal bones with cutmarks, deliberate breaks for marrow extraction, and other signs that the bodies hadbeen butchered for flesh in the same way as animals.

What happened to the Neanderthals?Neanderthals persisted for hundreds of thousands of years in extremely harsh conditions.They shared Europe for 10,000 years with Homo sapiens. Today they no longer exist.Beyond these facts the fate of Neanderthals has generated much debate.




Two main theories

Theory 1: Theory 1: They interbred with Homo sapiens sapiens on a relatively large scale. Followersof this theory believe that although Neanderthals as organisms no longer exist their geneswere present in early modern Europeans and may still exist today. Interbreeding dilutedNeanderthal DNA because there were signi cantly more Homo sapiens sapiens.Neanderthals were a sub-species of Homo sapiens rather than a separate species and hencetheir scientific name is Homo sapiens neanderthalensis.

Proponents of this theory cite the following as evidence:

there are features of Neanderthals in some Cro-Magnon (Homo sapiens)populations. For instance the discoverers of the 24,000-year-old skeleton of a modernhuman boy from Lagar Velho in Portugal, argue that although the pelvis and facialmorphology are sapien-like, the robusticity and limb proportions are moreNeanderthal-like. As the age of the skeleton is later than the time of the last knownNeanderthal, these features must represent significant interbreeding and transmissionof DNA between modern humans and Neanderthals. Cro-magnon remains fromVogelherd in Germany and Mladec in the Czech Republic also exhibit aNeanderthal-like projection of the occipital bun at the back of the skull, more so thanin later Homo sapiens. there are modern features in later Neanderthal populations. The VindijaNeanderthals look more modern than do other Neanderthals, which suggests thatthey may have interbred with incoming Homo sapiens. there are features of Neanderthals in modern Europeans. Some Europeans livingtoday have a similar shaped mandibular foramen (nerve canal in lower jaw) to theNeanderthals and the distinct retromolar gap (typical of Neanderthals) appears inisolated modern European populations.

Theory 2:Theory 2: They were essentially replaced by Homo sapiens. In this case, Neanderthals area separate species from Homo sapiens. This model does allow for peripheral interbreedingbut no significant genetic input from Neanderthals to modern Europeans.




Proponents of this theory cite the following as evidence:

studies of Neanderthal mitochondrial DNA ( rst extracted in 1997) show that it liesoutside the range of modern human mtDNA. Neanderthal mtDNA is four timesolder than that of Homo sapiens, hence scientists postulate a Neanderthal split fromthe line leading to modern humans about 500-600,000 years ago. The studies alsoreveal that Neanderthal mtDNA is no closer to modern European mtDNA thanmoderns from any other part of the world. analysis of the draft Neanderthal genome (the nuclear DNA and genes), released in2010, shows that modern human and Neanderthal lineages began to diverge about600,000 years ago. It also indicates that there was small-scale interbreeding as non-Africans derive about 1-4% of their DNA from Neanderthals. These results challengethe simplest version of 'Out of Africa' (which claims no interbreeding in its model formodern human origins) but do support the view that the vast majority of genes ofnon-Africans came with the spread of modern humans that originated in Africa. studies of the facial growth patterns of young Neanderthals show they developed indistinct ways to Homo sapiens. The di erences are therefore deeply genetic,contradicting the evidence of the Lagar Velho boy. The distinctive features includebrow ridges, chins, forehead and facial protrusion.

Why did they become extinct?

Various reasons have been proposed for the ‘replacement’ of Neanderthals by modernhumans. Today, most theories accept that Neanderthals displayed advanced behavioursand adaptive strategies and were not sluggish brutes that stood no chance against the vastlysuperior Homo sapiens. However,the incoming Homo sapiens were doing something thatwas di erent enough, and just that little bit more superior, to give them an edge under thecircumstances. Exactly what was 'a little bit more superior' is debated. Of particular interestare a number of new studies that focus on the role of climate change and the subtledifferences that behaviour and biology play in these conditions.

Perhaps their extinction was a combination of two or more of the following factors:




Biological

Neanderthal reproductive success and survival rates appear poor compared to Homosapiens. Most Neanderthal remains are of individuals rarely over 30 years old andover half are children. Slightly better rates of reproductive success and childhoodsurvival over 10,000 years could be all it took for Homo sapiens to replaceNeanderthals. Neanderthal metabolic rates appeared to be much higher than modern humans sowould have required more food to survive. In situations of plenty this would makelittle di erence, but in severe winters or unstable climatic conditions (see below), thedwindling resources would put pressure on populations that needed large amounts ofenergy from food. Claims that Neanderthals could not run as well as modern humans over longdistances is supported by evidence from Neanderthal ankles. Their heal bones arelonger than modern humans', resulting in a longer Achilles tendon. Shorter Achilles,as in modern humans, store more energy so are more e cient for running.Neanderthals generally didn't need to be good long-distance runners as they huntedin cooler regions using ambush tactics, but when conditions changed this could provea huge disadvantage. Evidence suggests this happened 50,000 years ago as much ofnorthern Europe changed from forest to tundra due to advancing ice sheets.Neanderthals were forced into isolated forest refuges in southern areas while modernhumans adapted to hunting on the increasingly widespread tundra.

Social and behavioural

Neanderthal culture lacks the depth of symbolic and progressive thought displayed bymodern humans and this may have made competing di cult. Neanderthal cultureremained relatively static whereas the contemporary Homo sapiens were steadilyevolving a complex culture. By the time Homo sapiens arrived in Europe 40,000years ago they had a highly developed cultural system. This is despite the fact that100,000 years ago there is relatively no cultural di erence between either species inthe archaeological record.




Neanderthals may have had limited speech and language capabilities compared toHomo sapiens and the extent of the di erences may have played a role in theirextinction. For instance, studies of the base of the skull suggest limited Neanderthalrepertoire and the position of the tongue in the mouth and larynx is also di erentfrom Homo sapiens. (This is a highly contentious theory with scientists on both sidesstrongly arguing for or against). Neanderthals may have lacked the adaptive nature of modern humans who hadcomplex social networks across wide areas. Smaller populations of Neanderthals thattended to stay in limited areas may have made them vulnerable to local extinctions. The survival techniques of Neanderthals were not as developed as Homo sapiens. Forinstance, studies on stress and build-up of tissue in Neanderthal bones indicatethey may have lacked systematic and directional planning in procuring food. ThisNeanderthal predominance of ‘brawn over brain’ may also be re ected in thenumber of skeletal injuries seen in both sexes, probably from close range hunting.Other studies show that 40% of Neanderthal remains have hypoplasia, a conditioncaused by lack of nutrients in early childhood. This is supported by tests onNeanderthal bone collagen which indicate that meat was very signi cant inNeanderthal diets to the point that they may be lacking the nutrients from othersources used by Homo sapiens, especially fresh water products and vegetable matter. Neanderthals may not have used their brains they way modern humans do as theirbrains were shaped di erently - modern human brains have expanded parietal andcerebellar regions. These regions develop in the rst year of life (Neanderthal infantsappear to miss this stage of development) and are linked to key functions like theability to integrate sensory information and form abstract representations ofsurroundings. Possible violent interactions with modern humans.




Environment or climate

New data on the glacial period that occurred from about 65,000 to 25,000 years ago(known as OIS-3) shows that it was a period of rapid, severe and abrupt climatechanges with profound environmental impacts. Although Neanderthals werephysically adapted to the cold, the severe changes in conditions (within individuals'lifetimes in many cases) allowed no time for populations to recover. Even smalladvantages in biology, behaviour or lifestyle, such as those mentioned above, wouldmean the di erence between life and death. The archaeological record indicates thatmodern humans had a wider range of adaptations which would have helped insurvival. There is another angle to the climate change theory. Evidence based on extensivesurveys of sites in Europe suggests that Neanderthal replacement was not due todirect competition with modern humans. Instead, evidence suggests that the severeconditions made the continent inhospitable for all humans living in Europe - andall populations died out about 30-28,000 years ago. However, there were othermodern human populations living in Africa that were able to recolonise Europe at alater date. As there were no Neanderthal populations elsewhere, they became extinct.

Fran Dorey , Exhibition Project Coordinator Last Updated: 30 October 2015


https://australianmuseum.net.au/staff/fran-dorey


(03) Homo neanderthalensis essay | Becoming Human

Homo neanderthalensisHomo neanderthalensis

Remains of Homo neanderthalensis have been found at sites throughout Europe, as well asin western Asia. Fossils assigned to this species are also found as far east as Uzbekistan, inCentral Asia. The sites from which this speciess is known, which are predominantly cavesites, date from roughly 150 thousand years ago (ka) to as late as roughly 30 ka. Homoneanderthalensis displays many unique features, including features in the skull andpostcranial skeleton (skeleton minus skull), which are related to their adaptation tohunting large game in cold environments. Homo neanderthalensis also had sophisticatedstone tool technologies designed to hunt large mammals at close range. This species isimportant to human evolution because it was contemporary with Homo sapiens and istherefore crucial to our understanding of the origin of our species.

Many of the unique features possessed by H. neanderthalensis are found in the skull. Aswith Homo erectus, the general shape of the Homo neanderthalensis skull is long and lowwith large browridges. Unlike those of H. erectus, however, the browridges of Homoneanderthalensis form individual arches above each eye orbit. (The evolutionarysigni cance of heavy brow ridges, called supra orbital tori, is not certain; scientists arecon dent they did not act as a visor against the sun, did not contribute to the structuralstrength of the cranium and were not needed as eye protection. Some researchers suggestbthey may have been part of a mate recognition system.) In this way, the Homoneanderthalensis skull resembles that of Homo heidelbergensis. The Homoneanderthalensis skull is quite large, with brain sizes averaging over 1400 cubic centimeters(cc.). Indeed, the brains of Homo neanderthalensis were bigger than those of Homosapiens; when judged in relation to body size (see below), however, the brain of Homoneanderthalensis is slightly smaller than that of Homo sapiens.

The middle and lower parts of the face are positioned far forward relative to the braincase(a condition called “midfacial prognathism”), giving the zygomatics (cheek bones) a “sweptback” appearance. The nasal aperture (hole for the nose) in Homo neanderthalensisis large, especially when compared to those of Homo sapiens. Because the widest point ofthe cranium (skull minus lower jaw) is across the middle of the braincase, the skull of

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H. neanderthalensis is oval-shaped when viewed from behind (the so-called “en bombe”shape). The braincase also exhibits unique features not found in other hominin species—e.g., occipital buns (thickened, projecting areas at the back of the skull) and suprainiacfossae (small depressions at the back of the skull, just above the occipital bun). Themandibles (lower jaws) are also large and bear molar teeth with large pulp chambers (thearea below the enamel in which nerves and blood vessels reside).

The Neanderthal postcranial skeleton also exhibits unique features. The entire postcranialskeleton is very heavily-built with thick bones. Individuals were short compared tomodern humans; their bodies were also wider, with wider shoulders, rib cages, and hips. The limb bones were short and the distal segments of the limbs (the bones of the forearmand lower leg) were particularly short. These features of the postcranial skeleton are similarto those seen in other mammals that live in cold environments. That is, the skeleton isshort and wide to minimize surface area (thereby minimizing heat loss) while maintainingthe same mass.

The fossil record of Homo neanderthalensis is large and this extensive record has allowedscientists to make interesting inferences about the lifesryle of this species using evidencegleaned from the skeleton. For example, the postcranial skeletons contain many healedfractures, particularly in the limb bones. Researchers suggest that these fractures are relatedto hunting dangerous prey at close range.

Important inferences can also be drawn from skull fossils of Homo neanderthalensis.Many scientists argue that the midfacial prognathism found in H. neanderthalensis is anadaptation to counteract strong forces placed on the front teeth during chewing or non-chewing behaviors (e.g., to hold hides while working them). This hypothesis is consistentwith the large degree of wear on the front teeth, which might also indicate the use of theseteeth as tools in hide working or other tasks. Other scientists have suggested that midfacialprognathism was a mechanism to increase the size of the sinuses in order to warm the air inthe cold environments in which Homo neanderthalensis lived. Teeth have also been usedto study the growth and development of this species. Some scholars argue that Homostudy the growth and development of this species. Some scholars argue that Homo




neanderthalensis growth and development was very di erent than that of Homo sapiens,suggesting that the Homo neanderthalensis did not possess features that are otherwiseunique to Homo sapiens. Other scientists, however, suggest that these di erences aremore minor and may overlap with the variation found in modern humans. These scholarsdo not exclude the possibility that Homo neanderthalensis shared unique developmentalfeatures with Homo sapiens.

Homo neanderthalensis individuals were adept large game hunters and this fact is re ectedin the archaeological remains associated with them. They employed a technique formaking stone tools called “prepared-core” or “Leavallois” technique. This techniqueinvolves removing akes from a core (source rock) in order to produce a ake (a chip ofstone removed from a core) of a desired shape. In particular, chips of stone are removedaround the perimeter of the core. A large ake is then removed from the “prepared” core;the shape of this ake is determined by how the original chips are from the core. The akeis then sharpened (and resharpened) by removing small akes on the edges (a techniquecalled “retouching”). In addition to points, these technique was also used to create othertools—particularly, many di erent kind of scrapers. However, Homo neandethalensisalso made non-prepared core tools. Speci cally, many late Neanderthal sites contain lithicassemblages (the entire collection of stone artifacts from an archaeological site) that werenot made using the prepared-core technique and thus more closely resemble Acheulueantools. Distances between the sites where stone tools have been discovered and the locationof the source of the raw material used to make the tools—often used as a proxy of the sizeof the range of hominin species—is greater i n Homo neanderthalensis than in Homoerectus, but less than that of Homo sapiens. This evidence suggests that the ranges ofNeanderthal populations were intermediate between those of Homo erectus an d Homosapiens.

Homo neanderthalensis also produced stone tools that closely resemble those made bycontemporary Homo sapiens in Europe. Although some scholars argue these tools re ectindependent innovations, most scientists believe that these tools are evidence thatNeanderthals were copying the tools made by H. sapiens. This position is corroborated by




the fact that these tools are normally found at Homo neanderthalensis sites that were closeto and contemporary with Homo sapiens sites. In addition, these tools are almost alwaysproduced using the same techniques used by H. neanderthalensis to make other tools. Inother words, the evidence suggests that Neanderthals made these H. sapiens-like tools usingthe same techniques they used to make tools prior to the arrival of Homo sapiens. Thus, itseems more likely that these tools are the result of H. neanderthalensis copying the end-products of H. sapiens stone tool technology, rather than an independent invention.

The evidence for symbolic artifacts—e.g., beads, statues, and cave art—are, by and large,absent from H. neanderthalensis sites. On the other hand, evidence of symbolic behavior iswidespread at Homo sapiens' sites. Despite skepticism from the majority of workers in the

eld, some scholars maintain some H. neanderthalensis sites bear symbolic artifacts—forexample, ochre used for body painting and shell beads. In addition, there is a lack ofevidence H. neanderthalensis buried its dead. Taken all together,the recortd has led mostscientists to accept that, at most, Neanderthals possessed a limited capability for symbolicbehavior and this may be linked to limitive cognitive capacity in this species.

H. neanderthalensis also possessed important adaptations for dealing with the coldenvironments in which it lived. For example, Neanderthal cave sites often contain hearthsand it is likely that this individuals of this species used animal hides to insulate themselvesfrom cold temperatures. There is no evidence, however, H. neanderthalensis sewed thesehides, as no artifacts associated with sewing (e.g., needles and awls) have been found atNeanderthal sites.

Consensus regarding the evolutionary relationships between H. neanderthalensis andother hominin species has not been reached. This controversy largely involves therelationship of this taxon and H. sapiens. This issue is dealt with in greater detail elsewhere(see essay on Homo sapiens), but the general consensus is that H. neanderthalensis was aseparate species from H. sapiens and that, although some interbreeding may have occurred,H. neanderthalensis did not make a lasting genetic contribution to H. sapiens.



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