(01) australopithecus anamensis | the smithsonian · genus australopithecus and early fossil...

(01) Australopithecus anamensis | The SmithsonianInstitution's Human Origins Program

Where Lived:Where Lived: Eastern Africa (Lake Turkana, Kenya andMiddle Awash, Ethiopia)

When Lived:When Lived: About 4.2 to 3.9 million years ago

Australopithecus anamensis has a combination of traits found in both apes and humans.The upper end of the tibia (shin bone) shows an expanded area of bone and a human-likeorientation of the ankle joint, indicative of regular bipedal walking (support of bodyweight on one leg at the time). Long forearms and features of the wrist bones suggest theseindividuals probably climbed trees as well.

History of Discovery: History of Discovery: In 1965, a research team led by Bryan Patterson from Harvard University discovered asingle arm bone (KNM-KP 271) of an early human at the site of Kanapoi in northernKenya. But without additional human fossils, Patterson could not con dently identify thespecies to which it belonged. In 1994, a research team led by paleoanthropologist MeaveLeakey found numerous teeth and fragments of bone at the same site. Leakey and hercolleagues determined that the fossils were those of a very primitive hominin and theynamed a new species called Australopithecus anamensis (‘anam’ means ‘lake’ in theTurkana lanaguage). Researchers have since found other Au. anamensis fossils at nearbysites (including Allia Bay), all of which date between about 4.2 million and 3.9 millionyears old.

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.

Australopithecus anamensis | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/evidence/human-fossils/species/australopithecus-anamensis

(01) Australopithecus anamensis | The SmithsonianInstitution's Human Origins Program

Below are some of the still unanswered questions about Australopithecus anamensis thatmay be answered with future discoveries:

First paper:

Leakey, M.G., Feibel, C.S., McDougall, I., Walker, A., 1995. New four-million-year-oldhominid species from Kanapoi and Allia Bay, Kenya. Nature 376,565-571.

Other recommended reading:

Leakey, M.G., Feibel, C.S., McDougall, I., Ward, C., Walker, A., 1998. New specimensand confirmation of an early age for Australopithecus anamensis. Nature 393, 62-66.

Ward, C. Leakey, M., Walker, A., 1999. The new hominid species Australopithecusanamensis. Evolutionary Anthropology 7, 197-205.

White, T.D, WoldeGabriel, G., Asfaw,B., Ambrose, S., Beyene, Y., Bernor, R.L.,Boisserie, J.-R., Currie, B., Gilbert, H., Haile-Selassie, Y., Hart, W.K., Hlusko, L.J.,Howell, F.C., Kono, R.T., Lehmann, T., Louchart, A., Lovejoy, C.O., Renne, P.R.,Saegusa, H., Vrba, E.S., Wesselman, H., Suwa, G., 2006. Asa Issie, Aramis and the originof Australopithecus. Nature 440, 883-889.

1. Is Au. anamensis a separate species from Au. afarensis? Many scientists think thefossil material of Au. anamensis and Au. afarensis represents a single lineage thatevolved through time.

2. Is Au. amanensis a direct descendant of the 4.4 million year old species Ardipithecusramidus?

Australopithecus anamensis | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/evidence/human-fossils/species/australopithecus-anamensis

(02) Australopithecus anamensis - Australian Museum

This hominin is the earliest known australopithecine and lived over 4 million years ago.

Background to discoveryAge

3.8 to 4.2 million years ago.

Important fossil discoveries

In 1965, a four-million-year old fossil arm bone was found in a remote area of Kenya butscientists needed more information before they could con dently name it. Thirty yearslater, a fossil hunting expedition led by Meave Leakey returned to the site. Additional fossildiscoveries showed that this was a new species and, in 1995, Australopithecus anamensiswas proclaimed.

In 2006, a new A.anamensis nd in Ethiopia was announced. The nd included a largecanine tooth and the earliest known Australopithecus femur.

Key specimens:

KNM-KP 29283 – a partial upper jaw with teeth discovered in 1994 in Kanapoi,Kenya. This specimen deomstrated the typical shallow palate and robust canine teethwith well developed roots and a pointed crown. KNM-KP 29281 – a partial lower jaw with teeth discovered in 1994 by Peter Nzubeand Maeve Leakey in Kanapoi, Kenya. This is the ‘type specimen’ or o cialrepresentative of this species. The teeth are arranged in parallel rows, which is an ape-like feature typical of this early ancestor. KNM-KP 29285 – upper and lower ends of a tibia discovered in 1994 in Kanapoi,Kenya

What the name means

Australopithecus is the genus or group name. It is derived from the Latin word ‘australo’meaning ‘southern’ and the Greek word ‘pithecus’ meaning ‘ape’. This ‘southern ape’name was created for another species discovered in South Africa but the name‘Australopithecus’ is now shared by several di erent species whose similarities place theminto the same group.

Australopithecus anamensis - Australian Museum

https://australianmuseum.net.au/australopithecus-anamensis


The word anamensis is based on the word ‘anam’ from the Turkana language used in thearea where fossils for this species were discovered. ‘Anam’ means ‘lake’ and is a reference tothe ancient lake-side environment once inhabited by this species.

Distribution

Fossils of this species have been found in the Middle Awash in northeast Ethiopia and atthree sites (Allia Bay, Kanapoi and Sibolot) scattered around Lake Turkana in Kenya,Africa.

Relationships with other speciesMany scientists think this species may be an ancestor of the well-known species,Australopithecus afarensis. Some even think these individuals are members of A.afarensisrather than a separate species but if this is the case, A.afarensis contains a highly variablepopulation.

Key physical featuresBody size

size was probably similar to that of modern chimpanzees there was an enormous di erence between the body sizes of males and females. Thisdi erence between the sexes (sexual dimorphism) in body size was similar in degree tothat shown by modern gorillas and orang-utans.

Brain

probably had a relatively small brain but more fossil material of the cranium is neededbefore brain size can be estimated




Jaws and teeth

jaws were ape-like in having: a jaw shape in which the side rows of teeth were arrangedin parallel lines; a lower jaw in which the bone below the front teeth was slopingbackward rather than projecting forward into a chin; and an upper jaw with a shallowpalate (roof of the mouth) teeth were intermediate between those of apes and humans and included: toothenamel that was thicker than that found in earlier ape-like ancestors; canine teeth thatwere still relatively large and pointed but were shorter than those found in earlier ape-like ancestors.

Limbs

the knee-end of the tibia (shin bone) was human-like as the upper surfaces of the twoknobs (condyles) at the top of the tibia were similar in size and concave in shape. Thisfeature indicates this species could walk bipedally (on two legs). marks on the wrist bones indicate these individuals had strong hand tendons usefulfor tree climbing the elbow joint was more human-like in being relatively exible, rather than the morerigid, locking elbows that quadrupedal (four-legged) apes have to support their bodiesas they move about forearms were relatively long and ape-like and useful for climbing

LifesyleCulture

Australopithecus anamensis may have used simple tools similar to those used by modernchimpanzees, including:

twigs, sticks and other plant materials that were easily shaped or modi ed. These mayhave been used for a variety of simple tasks including obtaining food. unmodi ed stones, that is stones that were not shaped or altered before being used.These tools may have been used to process hard foods such as nuts.




Environment and diet

Plant and animal fossils and the analysis of ancient sediments and rocks provide clues aboutthis species’ environment. They lived near an ancient inland lake that existed in the basinwhere Lake Turkana is now found.

The region was subject to volcanic activity and various volcanic eruptions produced layersof volcanic ash that covered the ground. The fossilised remains of this species were foundtrapped between di erent layers of ash and this has enabled this species’ fossils to be reliablydated to between 3.8 and 4.2 million years in age.

These early ancestors lived in forests and woodlands that grew near the lake. Theirskeletons show that they walked on two legs when on the ground and they probably spenta lot of time climbing trees, perhaps searching for food or avoiding predators. Their teethindicate they were plant-eaters, eating both fruits and hard-to-chew foods such as nuts.

Fran Dorey , Exhibition Project Coordinator Beth Blaxland , Education Project Officer Last Updated: 30 November 2010


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(03) Australopithecus anamensis essay | Becoming Human

Australopithecus anamensis

Fossils attributed to Australopithecus anamensis (which means “southern ape of the lake”from “anam,” meaning “lake” in the Turkana language) have been recovered fromsediments at Kanapoi and Allia Bay near Lake Turkana in Kenya. These fossils, whichhave been dated to between 4.2 and 3.9 million years ago using radioisotopic datingmethods applied to volcanic sediments, are signi cant because they represent the earliestindisputable evidence of obligate bipedality in the human fossil record. In addition, themorphology of the skull of Au. anamensis provides a glimpse of the evolutionary changesthat represent the transition from earlier, more primitive (i.e., ape-like) hominins—such asArdipithecus ramidus—to later, more derived (i.e., human-like) species—such asAustralopithecus afarensis.

Although Au. anamensis is represented by both cranial and postcranial (ifrom the parts ofthe skeleton other than the skull) remains, fossils representing the skull outnumber those ofthe limbs and trunk. Fossils of the jaws and teeth are particularly well represented. Au.anamensis possesses some features in the dentition—i.e., relatively large, broad premolarsand molars with relatively thick tooth enamel—that are shared with other species in thegenus Australopithecus and early fossil representatives of the genus Homo. Other featuresfound in the teeth of Au. anamensis, however, di er from those found in later species inthe genus Australopithecus and more closely resemble the condition found in living apes. These features include the size of the teeth in the front of the jaws (which are wider than inlater australopiths [species in the genera Australopithecus and Paranthropus]), the size andshape of the lower third premolar (which is larger and single-cusped, unlike the smaller anddouble-cusped condition found in later australopiths), the shape of the upper canine(which is symmetrical when viewed from the side, unlike the asymmetrical profile found inlater australopiths), and the shape of the rst deciduous (milk) molar (which, unlike lateraustralopiths, does not closely resemble a permanent molar). Canine size is smaller in Au.anamensis than in the genus Ardipithecus, but these teeth (especially their roots) are largerthan in Au. afarensis.

Australopithecus anamensis essay | Becoming Human

http://www.becominghuman.org/node/australopithecus-anamensis-essay


The skull of Au. anamensis is represented by fossils of the mandible (lower jaw), maxilla(the bone that comprises the upper jaw and the majority of the face), and a single temporalbone (the bone that surrounds the ear and forms part of the side of the skull). Like theteeth, these skull fossils bear many primitive, ape-like features. The dental arcade isgenerally U-shaped when viewed from above, with the molars and premolars locateddirectly behind the canines. This ape-like shape contrasts with the more parabolic-shapeddental arcade found in Au. afarensis and later hominins. In addition the front of themandible is ape-like in shape in side view, receding backward from top to bottom. In laterhominins, this region of the mandible is more vertically oriented. Due to the large size ofthe upper canine roots (see above), the rims of the nasal opening are rounded; in Au.afarensis, this rim is sharper. Finally, similar to that found in living apes, the bony earopening in Au. anamensis is relatively small in size.

The postcranial elements of Au. anamensis include fossils of the hindlimb ) and forelimb,including portions of the wrist and hand. The tibia fossils are of particular importancebecause they demonstrate that this species walked bipedally. Both the knee- and ankle-endsof the tibia (shin bone) are thickened and the tibial plateau, where the tibia connects to thefemur (thigh bone), is larger than in living apes. These features prove that Au. anamensiswas a biped because they indicate that more weight was borne on the tibia, a featurerequisite for bipedality. In addition, the shaft of the tibia is straight and the end of thisbone that articulates with the ankle is upright in contrast to the angulation found in theseregions in living apes. The con guration of these joints demonstrates that the knee andankle joints were reorganized to accommodate a bipedal gait. The single wrist bone of Au.anamensis suggests that this species had limited ability to rotate the bones of the hand onthose of the wrist, similar to later australopiths and species in the genus Homo, but unlikeliving apes. Finally, estimates of body size suggest that, at roughly 47-55 kilograms, Au.anamensis was slightly larger than Au. afarensis and Ar. ramidus and sexual dimorphism(i.e., size and shape di erences between males and females of the species) was similar to thatfound in Au. afarensis.




The evolutionary relationships between Au. anamensis and Au. afarensis have received agreat deal of scholarly interest. The fossils of Au. anamensis from Kanapoi are geologicallyolder than those from Allia Bay and are more similar to Ar. ramidus and living apes. Inaddition, the Au. anamensis sample from Allia Bay is more similar to the older sample ofAu. afarensis fossils found at Laetoli, Tanzania than they are to the younger sample of Au.afarensis fossils from Hadar, Ethiopia. These facts have led some researchers to suggest Au.anamensis is the direct ancestor of Au. afarensis and the sequence of fossils from Kanapoi,Allia Bay, Laetoli, and Hadar can be considered a single species. The trends suggesting thatthis sequence of fossils represents a single species come predominantly from the size andshape of the mandible and lower third premolar. For clarity and to formalize thedi erences found in this single species, which would include fossils currently assigned toAu. afarensis and Au. anamensis, however, most scholars continue to regard the fossils asseparate species—i.e., the fossils from Allia Bay and Kanapoi are referred to as Au.anamensis and the fossils from Laetoli and Hadar (and a handful of other sites, see essay onAu. afarensis) are referred to as Au. afarensis.

The environments in which Au. anamensis lived have been reconstructed as forestedhabitats near streams. Combined with evidence from other early purportedly bipedalhominin species (e.g., Ardipithecus kadabba and Ar. ramidus) , these environmentalreconstructions argue strongly against the once wide-held idea that bipedalism initiallyevolved and flourished in open savanna environments.



(01) A. garhi | The Smithsonian Institution's Human Origins Program

Australopithecus garhi

Where Lived: Where Lived: Eastern Africa (the site of Bouri,Middle Awash, Ethiopia)

When Lived: When Lived: About 2.5 million years ago

This species is not well documented; it is de nedon the basis of one fossil cranium and four otherskull fragments, although a partial skeleton found

nearby, from about the same layer, is usually included as part of the Australopithecus garhisample. The associated fragmentary skeleton indicates a longer femur (compared to otherAustralopithecus specimens, like ‘Lucy’) even though long, powerful arms weremaintained. This suggests a change toward longer strides during bipedal walking.

Year of Discovery: Year of Discovery: 1990

History of Discovery: History of Discovery: The human fossil record is poorly known between 3 million and 2 million years ago,which makes the nds from the site of Bouri, Middle Awash Ethiopia, particularlyimportant. First in 1990 and then from 1996 to 1998, a research team led by Ethiopianpaleoanthropologist Berhane Asfaw and American paleoanthropologist Tim White foundthe partial skull (BOU-VP-12/130) and other skeletal remains of an early humans dated toaround 2.5 million years old. In 1997, the team named the new species Australopithecusgarhi; the word ‘garhi’ means ‘surprise’ in the Afar language.

Australopithecus garhi | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/node/759

http://humanorigins.si.edu/evidence/human-fossils/species/australopithecus-garhi

(01) A. garhi | The Smithsonian Institution's Human Origins Program

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 Australopithecus garhi that may beanswered with future discoveries:

1. Will scientists recover more individuals from this species? Until they do, it is hard todetermine exactly where this species fits on the human family tree.

2. Did Au. garhi actually make and use the stone tools found nearby?3. Is it possible the Au. garhi skull BOU-VP-12/130 is really a female Paranthropus

aethiopicus or a late Australopithecus afarensis specimen?

First paper:

Asfaw, B., White, T., Lovejoy, O., Latimer, B., Simpson, S., Suwa, G., 1999.Australopithecus garhi: a new species of early hominid from Ethiopia. Science 284,, 629-635.

How They Survived: How They Survived: Fossils of Australopithecus garhi are associated with some of the oldest known stone tools,along with animal bones that were cut and broken open with stone tools. It is possible,then, that this species was among the rst to make the transition to stone toolmaking andto eating meat and bone marrow from large animals.

Evolutionary Tree Information: Evolutionary Tree Information: Some scientists claim that the large molar teeth show that Australopithecus garhi is relatedto Paranthropus aethiopicus; however, the combination of features of the face, braincase,and teeth are unlike Paranthropus. The scientists who originally reported the nds thinkthat Au. garhi may represent an ancestor of the genus Homo.

Australopithecus garhi | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/evidence/human-fossils/species/australopithecus-garhi

(02) Australopithecus garhi - Australian Museum

This hominin lived 2.5 million years and, although similar to other australopithecines,it displayed some surprising features.

Background of discovery Age - 2.5 million years ago


The type specimen (BOU-VP-12/130) is a partial cranium discovered in 1997 in Bouri,Ethiopia. A second cranium, lower jaws and a partial skeleton have been found at nearbysites. These may represent the same species, however the discoverers point out that theskeletal remains need not belong to the same species as the skulls. This species wasannounced in 1999.

What the name means

The genus or group name Australopithecus is derived from the Latin word ‘australo’meaning ‘southern’ and the Greek word ‘pithecus’ meaning ‘ape’. The species name, garhi,means ‘surprise’ in the Afar language. This name was chosen because the scientists whodiscovered the skull were surprised by some of the features of the skull, in particular theenormous back teeth.

Distribution - Middle Wash, Bouri, Ethiopia

Relationships with other speciesMore fossils are needed before it is possible to determine where this species ts on ourfamily tree. Its similarity to A.afarensis suggests it evolved from this species. It may be adirect ancestor of modern humans, representing an evolutionary link between theAustralopithecus and Homo, or it may belong on a side-branch.

Australopithecus garhi - Australian Museum

https://australianmuseum.net.au/australopithecus-garhi


Key physical featuresBrain - size about 450 cc, similar to other australopithecines

Body size and shape - probably slightly larger than A.afarensis

Jaws and teeth

very large canines, molars and premolars thick tooth enamel rectangular or U-shaped dental arcade diastema (gap between canines and incisors) often present in the upper jaw. This is aprimitive feature. similar in appearance to A.afarenis but has more advanced features in the teeth

Skull

prognathous or projecting lower face like many australopithecines, including some A.afarensis, it has a sagittal crest foranchoring large jaw muscles

Limbs

limb bones (although it is debated whether they belong to this species) are intermediate inproportion between A.afarensis and H.ergaster. Arm length was relatively long, but leglength was more humanlike compared to A.afarensis.




LifestyleEnvironment and diet

A changing climate had thinned the forests that once dominated this region, and savannahgrasslands were becoming widespread.

It most likely ate plant material and possibly some meat. If the antelope bones found at thesite were butchered by this species, then they must have included signi cant amounts ofmeat and marrow in their diet.

Culture

The skeletal remains were found associated with antelope bones bearing cut marks,apparently from stone tools. Stone tools were not found at this site, but at the nearby,contemporaneous site Gona. These are the earliest dated stone tools that have been found,but may have been left by another species.

Fran Dorey, Exhibition Project Coordinator Last Updated: 27 October 2009




(03) Australopithecus garhi essay | Becoming Human

Australopithecus garhi

Australopithecus garhi (“garhi” means “surprise” in the Afar language) is a gracileaustralopith species (a species of Australopithecus not displaying the suite of characteristicsrelated to strong chewing found in the robust australopiths—species in the genusParanthropus) found in the Middle Awash of Ethiopia. Found in deposits dated to 2.5million years ago (mya) by radioisotopic and biochronological (a technique using therelative time frames of extinct non-hominin animals) methods, Au. garhi is importantbecause it may be the oldest hominin species to make stone tools. This possibility isdiscussed further, below.

While Au. garhi retains many primitive features (features that are shared with its ancestors),it also exhibits derived features (features that are di erent from its ancestors) in thedentition. This unique morphological combination shows that a number of homininspecies were likely adapting to chew tougher or harder foods at the same time, but indifferent ways.

Au. garhi is only known from a handful of specimens. The most important specimen is apartial cranium (skull minus lower jaw), comprising parts of the frontal and parietal bones(the bones forming the brain case, enclosing the top and sides of the brain), maxilla (thebone that comprises the majority of the face and the upper jaw), and teeth. Otherpostcranial (limb and torso) remains have been found in the same layers, but because theyhave not been found associated directly with craniodental material (material from the skulland teeth), they cannot be attributed de nitively to Au. garhi. However, no otherhominin species have been found in these deposits, lending support to the hypothesis thesefossils belong to Au. garhi.

Australopithecus garhi essay | Becoming Human

http://www.becominghuman.org/node/australopithecus-garhi-essay


This postcranial material shows a more human-like limb proportions. In particular, likeHomo sapiens, these remains have longer femora (plural of femur, thigh bone) than Au.afarensis. In H. sapiens, this ratio relates to bipedal locomotion. If these postcranialremains belong to Au. garhi it would imply that Au. garhi walked bipedally and that thisbipedality, based on the derived features of the postcrania, was perhaps more like H.sapiens than earlier hominins. However, the forearm to upper arm proportions are moresimilar to those of an ape.

The craniodental remains of Au. garhi combine traits that are similar to Au. afarensis andolder hominins and traits (especially in the teeth) that resemble those of the robustaustralopiths. As with Au. afarensis and other earlier hominin species, Au. garhi has aprognathic face (a face that juts forward), large canines compared to the size of its molars,and a sagittal crest (the raised line along the top of the skull where the temporalis muscle—achewing muscle that closes the jaw—attaches). Its cranial capacity (the volume of the braincase, which approximates brain size) is estimated at 450 cubic centimeters, similar in size toother gracile australopiths (e.g., Au. afarensis). However, Au. garhi has much larger post-canine (molar and premolar) teeth than Au. afarensis; the size of these teeth is similar tospecies in the genus Paranthropus. This combination of features shows that the suite ofcharacteristics related to chewing exhibited by the robust australopiths, such as theextremely large sagittal crest, ared zygomatic bone (the bone comprising the cheek), anddished face (a face with cheeks that extend forward further than the nose), do not alwaysoccur with increased size in the post-canine teeth.




The most surprising fact about Au. garhi is that it occurs in the same layers as stone toolsand animal bones with cut marks. These stone tools are the earliest known aked tools(part of the Oldowan tradition, the simplest form of stone tools) to be found in layers withhominins; the oldest stone tools, dated to 2.6 mya, are not found in layers with homininremains. These stone tools are also found with animal bones showing marks made fromstone tools, indicating that whichever hominins used these tools were butchering animalsand eating their meat. Because no other hominins have been found in these layers, somescientists believe that Au. garhi was the maker and user of these tools; it is possible howeverthat another hominin made and used these tools without leaving fossilized remains in theselayers. If Au. garhi is responsible for these artifacts, it is the only hominin outside the genusHomo which fashioned stone tools; such a nding would contradict the assumptionprevailing among many paleoanthropologists that only species in the genus Homo had thisability. (Note: The hypothesis early Homo species wre the makers of the rst stone toolswas further undermined by the discovery at Dikika, Ethiopia in 2009 of ntelope and bovidbones bearing cut marks that could only have been made by stone tools. The stone toolshave not been found but the cut marked bone has been dated to 3.4 ma, a time and placewhere the only hominin species was Australopithecus afarensis..)

Scientists have reconstructed the layers in which Au. garhi was found as the edge of a lake,probably surrounded by grassland. If Au. garhi was the rst hominin to make and usestone tools, this reconstruction might provide insights into the habitats in which thisimportant adaptation occurred.



(04) Australopithecus garhi - Various Sources

"The hominin remains were initially believed to be a human ancestor species and the nalmissing link between the Australopithecus genus and the human genus, Homo. Howeverit is now believe that A. garhi, although more advanced than any other australopithecine,was only a competitor species to the species ancestral to Homo and therefore not a humanancestor."

Australopithecus garhi - Various Sources

(04) Australopithecus garhi - Various Sources

One of the more striking features of the A. garhi remains is the size of the postcaninedentition, which is at or beyond the nonrobust australopithecine or A. robustus extremes.This is the only feature that suggests any link to the robusts, and as such it is very unlikelythat the specimen is in any way derived from or is a sister species to robustus. This is seenespecially in the large size of the anterior teeth, exceeding those of the largestaustralopithecines and far exceeding the robusts, who are marked by anterior toothreduction or stasis. Based on tooth size, the garhi material seems to t well with schemesthat see either one or both of africanusand afarensis as a direct human descendent, as thecanine-to-premolar/molar size ratios are comparable to both species and early Homo.

http://archaeologyinfo.com/australopithecus-garhi/

"The validity of Australopithecus garhi as a type distinct from its contemporary, the muchbetter characterized Australopithecus afarensis, is still controversial. Though its name,garhi, meaning "surprise," suggests it was a remarkable nd, it will be far more surprising ifAustralopithecus garhi survives as a separate, recognized taxon. The fossil material onwhich it is based will, however, retain its signi cance even if it is not in the end judgeddistinct, since it comes from East Africa at a time when there are relatively few hominidfossils known."

http://www.macroevolution.net/australopithecus-garhi.html

Australopithecus garhi - Various Sources

(01) A. africanus | The Smithsonian Institution's Human Origins Program

Australopithecus africanus

Where Lived: Where Lived: Southern Africa (South Africa)

When Lived: When Lived: About 3.3 to 2.1 million years ago

Au. africanus was anatomically similar to Au. afarensis, with a combination of human-likeand ape-like features. Compared to Au. afarensis, Au. africanus had a rounder craniumhousing a larger brain and smaller teeth, but it also had some ape-like features includingrelatively long arms and a strongly sloping face that juts out from underneath the braincasewith a pronounced jaw. Like Au. afarensis, the pelvis, femur (upper leg), and foot boneso f Au. africanus indicate that it walked bipedally, but its shoulder and handbones indicate they were also adapted for climbing,


History of Discovery: History of Discovery: The Taung child, found in 1924, was the first to establish that early fossil humans occurredin Africa. After Prof. Raymond Dart described it and named the species Australopithecusafricanus (meaning southern ape of Africa), it took more than 20 years for the scienti ccommunity to widely accept Australopithecus as a member of the human family tree.

Height: Height: Males: average 4 ft 6 in (138 cm); Females: average 3 ft 9 in (115 cm)

Weight: Weight: Males: average 90 lbs (41 kg); Females: average 66 lb (30 kg)

Australopithecus africanus | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/evidence/human-fossils/species/australopithecus-africanus


We don’t know everything about our early ancestors—but we keep learning more!Paleoanthropologists are constantly in the eld, excavating new areas, usinggroundbreaking technology, and continually lling in some of the gaps about ourunderstanding of human evolution.

Below are some of the still unanswered questions about Au. afarensis that may beanswered with future discoveries:

1. Au. africanus is currently the oldest known early human from southern Africa.Where did it come from? Was it a descendent of Au. afarensis from Eastern Africa?

2. Is Au. africanus part of the lineage that led to our own species, Homo sapiens?3. In 1994, scientist Ron Clarke found four left early human foot bones while searching

through boxes of fossils at Sterkfontein, a site in South Africa where most Au.africanus fossils come from. He dubbed this fossil "Little Foot", and has since foundthat it comes from a 3.3-million-year-old partial skeleton, most of which is stillembedded in the cave sediments. When this fossil is completely excavated, it will shedlight on several questions about this species (if it is designated as an Au. africanusindividual): How big was it? What did its post-cranial skeleton look like? How does itcompare to STS 14, another partial skeleton of Au. africanus?

First paper:

Dart, R., 1925. Australopithecus africanus. The man-ape of South Africa. Nature 115,195-199.

Other recommended readings:

Berger, L.R., Clarke, R.J., 1995. Eagle involvement of the Taung child fauna. Journal ofHuman Evolution 29, 275-299.

Clarke, R.J., Tobias, P.V., 1995. Sterkfontein Member 2 foot bones of the oldest SouthAfrican hominid. Science 269, 521–524.


http://humanorigins.si.edu/node/758



Lacruz, R.S., Rozzi, F.R, Bromage, T.G., , 2005. Dental enamel hypoplasia, age at death,and weaning in the Taung child. South African Journal of Science 101, 567-569.

McHenry, H., 1998. Body proportions in Australopithecus afarensis and A. africanus andthe origin of the genus Homo. Journal of Human Evolution 35, 1-22.

Scott, R. S., Ungar, P.S., Bergstrom, T.S., Brown, C.A., Grine, F.E, Teaford, M.F.,Walker, A., 2005. Dental microwear texture analysis shows within-species diet variabilityin fossil hominins. Nature 436, 693-695.

How They Survived: How They Survived: The hunter or the hunted?The hunter or the hunted?

No stone tools have been discovered in the same sediments as Au. africanus fossils;however, for a long time researchers believed Au. africanus was a hunter. Raymond Dartcreated the term ‘osteodontokeratic’ culture (osteo = bone, donto = tooth, keratic = horn)in the 1940s and 1950s because remains of this species were found alongside brokenanimal bones. Dart assumed these broken animal bones, teeth and horns were used by Au.africanus as weapons; however, in the 1970s and 1980s, other scientists began to recognizethat predators such as lions, leopards, and hyenas were instead responsible for leaving thesebroken animal bones. These predators even ate Au. africanus individuals, too.

Despite the carnivorous preferences of their contemporaneous predators, Au. africanusindividuals had a diet similar to modern chimpanzees, which consisted of fruit, plants,nuts, seeds, roots, insects, and eggs.




How do we know what they ate?How do we know what they ate?

Scientists can tell what Au. africanus may have eaten from looking at the remains of theirteeth---tooth-size, shape, and tooth-wear can all provide diet clues. Dental microwearstudies found more scratches than pits on Au. africanus teeth compared to acontemporaneous species, P. robustus. This pattern indicates that Au. africanus ate toughfoods but also had a very variable diet including softer fruits and plants.

Evolutionary Tree Information: Evolutionary Tree Information: Many scientists consider either this species o r Au. afarensis of East Africa to represent aviable candidate for the ancestor of the genus Homo.



https://australianmuseum.net.au/image/Australopithecus-africanus-skull/

(02) Australopithecus africanus - Australian Museum

This species was the first of our pre-human ancestors to be discovered.

‘Mrs Ples’ Australopithecus africanus skull Photographer: Stuart Humphreys © Australian Museum

This species was the rst of our pre-human ancestors to be discovered, but was initiallyrejected from our family tree because of its small brain. This opinion changed when newevidence showed this species had many features intermediate between apes and humans.

Background of discoveryAge

This species lived between 3.2 and 2 million years ago.


Australopithecus africanus - Australian Museum

https://australianmuseum.net.au/australopithecus-africanus


In 1924, a fossil was rescued from a limestone quarry at Taung in South Africa and sent toAustralian, Raymond Dart who was a Professor of Anatomy in nearby Johannesburg. Thenow-famous Taung Child skull had a mixture of human-like and ape-like features. Dartbelieved it to be an early ancestor of humans and in 1925 he gave his ‘man-ape’ a newspecies name, Australopithecus africanus.

Dart had di culty convincing other scientists that this was a human ancestor, partlybecause at the time, many believed human ancestors had large brains and ape-like jawswhereas the Taung Child had the opposite set of features. Acceptance only arose in the late1940s after Robert Broom’s discoveries of more fossils including those of adults. Sincethen, many hundreds of Australopithecus africanus fossils have been found in SouthAfrica.

Key specimens:

Sts 14: a partial skeleton discovered in1947 by Robert Broom and John Robinson inSterkfontein, South Africa. The shape of this pelvis proved Australopithecus africanuswas able to walk upright on two legs. The spine has six lumbar vertebrae in the lowerback. This is a human-like rather than an ape-like feature as modern humanssometimes have six but usually have ve lumbar vertebrae whereas modern Africanapes have five or less. MLD 2: a lower jaw from an adolescent discovered in Makapansgat, South Africa Taung Child: a partial skull and brain endocast discovered in 1924 in Taung, SouthAfrica. This 2.3 million-year-old skull of a young child is the ‘type specimen’ oro cial representative of this species. It was the rst fossil of a human ancestor everfound in Africa and was also the rst to be classi ed in the genus Australopithecus.We know this individual was a young child because its rst molar teeth were in theprocess of erupting from the jaw.




Sts 71: a 2.5 million-year-old partial skull discovered in1947 by Robert Broom andJohn Robinson in Sterkfontein, South Africa. The robust features of this skullindicate it was an adult male. ‘Mrs Ples’ or Sts 5: this 2.5 million-year-old skull discovered in 1947 by RobertBroom and John Robinson in Sterkfontein, South Africa. The skull was nicknamed‘Mrs Ples’ because it was originally considered to be an adult female from the genusPlesianthropus. Later, it was decided that the skull was actually an Australopithecusafricanus individual and there is also some debate about whether this skull was that ofa female or male.

Malapa homininsMalapa hominins

Fossils from two individuals were recovered in 2008 and announced as a new speciesAustralopithecus sediba in 2010. More fossils are in the process of being excavated. Manyother palaeontologists consider the ‘A. sediba’ fossils to be a chronospecies of A. africanus –meaning that the slight anatomical di erences between the new fossils and A. africanus aredue to changes over time within a species rather than them being from di erent species.This view makes the fossils merely an interesting side branch of our family tree but doesextend the time range for A. africanus by almost half a million years

Key specimens are the type specimen Malapa Hominin 1 (MH1), which is considered to bea juvenile and is represented by a partial cranium (UW 88-50), partial lower jaw (UW88-8)and postcranial elements including a right clavicle (UW 88-1); and Malapa Hominin 2(MH2), a probable female adult represented by partial lower jaw (UW 88-54), isolatedteeth from the lower jaw (UW 88-54) and some partial postcranial elements includingmost of the right arm, ankle and knee joints and bits of the pelvis and shoulder blade.MH2 is the species paratype (a specimen other than a type specimen that is used for theoriginal description of a taxonomic group).

DistributionDistribution

All known specimens have been found at various locations in South Africa




What the name meansWhat the name means

Australopithecus, means ‘southern ape’. It is based on ‘australo’, a Latin word meaning‘southern’ and ‘pithecus’, a Greek word meaning ‘ape’. The name was originally createdjust for this species found in South Africa but several closely related species now share thesame genus name.

The word africanus is a Latinised form of the word ‘Africa’ and indicates the continentwhere this species was found.

Relationships with other speciesAustralopithecus africanus was once considered to be a direct ancestor of modern humansbut new nds have challenged this position. Many scientists now believe this speciesrepresents a side branch in our evolutionary family tree but there is disagreement about itsexact relationship to other species.

Many of the fossils found at South African sites in the 1930s and 1940s were given separatenames, such as Australopithecus transvaalensis, Plesianthropus transvaalensis andAustralopithecus prometheus. These are all now recognised as belonging to the samespecies, Australopithecus africanus.

Fossils discovered in Malapa, South Africa, in 2008 were announced as a new speciesAustralopithecus sediba in 2010, but many other palaeontologists consider the fossils to bea chronospecies of A. africanus – meaning that the slight anatomical di erences betweenthe new fossils and A. africanus are due to changes over time within a species rather thanthem being from di erent species. This would extend the time range for A. africanus byalmost half a million years.




Key physical featuresBody size and shape

females grew to about 110 centimetres in height and males were slightly taller atabout 135 centimetres ape-like features included a cone-shaped rib cage and relatively long arms

Brain:

averaged approximately 480 cubic centimetres. This was small but still relatively largewhen compared with a modern chimpanzee’s brain.

Skull:

compared with the earlier species, Australopithecus afarensis, the skull showed someslightly more human-like features such as a smaller brow ridge and a slightly arched(rather than flat) forehead area. like all human ancestors, the spinal cord emerged from the central part of the base ofthe skull rather than from the back.

Jaws and teeth:

jaws and teeth were intermediate between those of humans and apes and those ofearlier species, such as Australopithecus afarensis the canine and incisor teeth had become shorter and smaller a gap (diastema) between the canines and adjacent teeth was rare premolar teeth and molar teeth were all quite large




Limbs:

leg and foot bones indicate that this species had the ability to walk on two legs. they also indicate some ape-like features including slightly curved nger and toebones and arms that were quite long, although not longer than their legs.

Pelvis:

was fully adapted for walking on two legs but compared with those of modern humans itwas less rounded, had a narrower birth canal, and was not specialised for a striding gait.

LifestyleCulture

This species probably used simple tools such as sticks found in the immediate surroundingsand scavenged animal bones. Stones may also have been used as tools, however, there is noevidence that these stones were shaped or modified.


Over 2.5 million years ago, this species occupied an environment in South Africa in whichthere was a mixture of woodland and savannah grassland. After 2.5 million years ago, theclimate became drier and savannah grasslands spread.

Analysis of tooth wear patterns suggests that Australopithecus africanus had a diet thatincluded fruit and leaves. Chemical analysis of the teeth also suggests that some meat wasincluded in the diet but not in signi cant amounts. It is likely that they may havescavenged for meat rather than hunted.

Fran Dorey , Exhibition Project Coordinator Last Updated: 25 September 2015




(03) Australopithecus africanus essay | Becoming Human

Australopithecus africanus

The rst member of its genus to be discovered, Australopithecus africanus is the oldestspecies of hominin to be found in southern Africa. Cave sites where it is found have beendated approximately to 3-2.0 ma based mostly on biochronological methods (datingmethods utilizing the relative chronologies of non-hominin animal fossils). Itsmorphology is similar to Australopithecus afarensis, but it has important di erences in theskull and teeth. The fact that Au. africanus shares some morphological features with Au.afarensis, others with members of the Paranthropus genus, and others with early Homospecies makes it a di cult species to place in the hominin lineage. Thus, understandingAu. africanus is central to understanding early hominin phylogeny.

The rst specimen of Au. africanus to be found, in 1924, was a juvenile skull from the siteof Taung in South Africa. The biologist Raymond Dart believed that this specimen was amember of the hominin clade based on the forward positioning of the foramen magnum(the hole in the base of the skull where the spinal cord connects with the brain), which isseen in humans and other bipedal hominins. Many scientists at the time did not believeDart’s assertion and thought the skull was of a non-hominin ape, particularly because theythought that hominins would have larger brains than that possessed by Au. africanus. Thisbelief was held in part because of a fossil skull and jaw found in England, called PiltdownMan, which had a large brain like a human but with a jaw and teeth that were moreprimitive (more like those of an ape). This fossil played to scientists’ beliefs that the bigchange between humans and apes would be seen rst in the size of the brain; it also showedhuman evolution to have occurred (at least partially) in Europe, which agreed with manyscientists’ Eurocentric views better than would an African evolution for humans.

Australopithecus africanus essay | Becoming Human

http://www.becominghuman.org/node/australopithecus-africanus-essay


In time, the Piltdown fossil was shown to be a fake, simply a human skull and anorangutan jaw with led down teeth, but for the rst part of the 20th century PiltdownMan was considered to be the best case for a member of the lineage between apes andhumans. It was not until the 1950s that Au. africanus was recognized by the scienti ccommunity as such, a true hominin. By this time, a number of cranial and otherpostcranial (skeletal material not from the skull) specimens attributed to Au. africanus hadbeen found in limestone caves at Sterkfontein, Taung, and Makapansgat, all in SouthAfrica. These sites are limestone caves that were eaten away by rainwater and lled withanimal remains and sediments from the surface.

Because of this context, the sites at which Au. africanus has been found do not have easilyde ned layers and dating of the sites is di cult, especially since South Africa lacks volcaniclayers that would allow for radioactive isotopic dating (dating of the volcanic materialusing the timing of decaying isotopes within the material). Thus, these sites are primarilydated using biochronological methods. The fauna that are used to date these sites have alsoled scientists to reconstruct the habitats at which Au. africanus lived as woodland and openwoodland savanna.

The morphology of Au. africanus is similar to A. afarensis in many ways. For instance, it issmall-bodied compared to later hominins and possesses the pelvic structures andadaptations to the legs and feet that characterize habitual bipeds, such as a broad, shortpelvis and a valgus knee (a knee that is angled underneath the body). It also has curvedphalanges ( nger bones) like Au. afarensis; this fact, coupled with nding remains in areasreconstructed as wooded environments, has led to the possibility that Au. africanus spentat least some time in trees. Au. africanus also lacks many features associated withconsumption of hard foods; for example, Au. africanus lacks sagittal crests (crests along themidline of the skull where chewing muscles attach) and ared zygomatics (cheek bones),which are found in most specimens assigned to Paranthropus boisei and robustus (seeessays for these species).




However, Au. africanus has a slightly larger estimated brain size than Au. afarensis, and haslarger post-canine teeth (molars and premolars) and smaller anterior teeth (incisors andcanines) than does Au. afarensis, traits it shares with members of Paranthropus. Thesetraits are derived relative to A. afarensis; that is, they are di erent than the condition foundin A. afarensis and have evolved in the lineage leading to Au. africanus. Au. africanus alsohas a slightly less prognathic (projecting) face, although this trait is variable in the species. This species also has a more exed basicranium (a skull base that is more angulated in thecenter). In addition, Au. africanus has a trait called anterior or nasal pillars, which are abuttressing of bone on either side of the nasal opening of the skull on the maxilla (the bonecomprising the majority of the face). Although the exact function of this trait is not wellunderstood, some scientists have suggested that this is an adaptation to the forces ofchewing hard foods. This trait is also commonly seen in P. robustus, but is not present inother hominins.

Au. africanus also has derived traits that are not found in any of the other australopiths orParanthropus members. These include a taller frontal bone (the bone that makes up theforehead) and an occipital bone (the bone at the back of the skull) with a longer and atterorientation on the bottom and a higher point of directional change towards the top of thebone, which results in a higher, more rounded shape for the back of the skull. Thesederived traits are also found in Homo species.

Overall, these traits suggest that Au. africanus may have evolved from Au. afarensis or asimilar, as of yet unknown, hominin. The changes in the dentition and buttressing in theface may indicate that Au. africanus was eating a harder or tougher diet than was Au.afarensis. However, studies of microwear (the scratches and pits left on the teeth bychewing of food) suggest that Au. africanus was not eating a diet similar to that ofmembers of the paranthropines.




The relationship of Au. africanus to other hominins is not well understood. Most scientistsagree that Au. africanus evolved from Au. afarensis or a similar hominin, but therelationship between it and later hominins is unclear. This cloudiness results in partbecause A. africanus is old enough to be an ancestor to many di erent hominins, and inpart because it shares some traits with di erent groups of these hominins but not others. Because Au. africanus retained some primitive characters (those characters that are foundin a common ancestor and are unchanged in its descendants; in contrast to derivedcharacteristics), such as the lack of sagittal crests and ared zygomatics, that are shared withearly members of the Homo lineage, Au. africanus was originally considered to be a directancestor to the Homo lineage. In addition, Au. africanus shares derived characters of theskull (listed above) with Homo and no other hominins. However, Au. africanus sharessome derived traits with all members of the Paranthropus genus, but not with Homo,which indicate it might be an ancestor to the Paranthropus genus. It also shares thepresence of anterior pillars with only P. robustus, which may indicate that it is a directancestor to only this species. This last hypothesis would indicate that the Paranthropusgenus was not monophyletic (did not contain an ancestor species and all of its descendentspecies), since Au. africanus is not included in this genus but is most closely related to amember of this genus. Thus, where Au. africanus truly ts in is important tounderstanding many of the relationships within the hominin lineage.

Another important topic of discussion surrounding Au. africanus is the level of variationseen between individuals of this species. The variation in many characteristics such asmolar size and facial structure is larger than that seen in any living apes. This point has ledsome scientists to believe that the species Au. africanus actually consists of two separatespecies. These di erences still stand even when considering Au. africanus to be a verysexually dimorphic species (a species with two body forms and/or sizes, one male and onefemale, a trait that occurs in many primates, including humans). If Au. africanus wasactually two species, some of our hypotheses about the relationship of Au. afrricanus toother hominins could be refined.



(04) CT scans show Australopithecus africanus not as ‘human’ as thought

August 25, 2014

The 3-million-year old skull of the Taung Child considered the premiere evidence thatAustralopithecus africanus was distinctively human has been shown to be not too humanafter all. Ralph L. Holloway with the Department of Anthropology at ColumbiaUniversity in New York and colleagues have produced convincing evidence that theTaung Child skull does not show human-like development that has been claimed for thelast 90 years. The research was published in the Aug. 25, 2014, edition of the journalProceedings of the National Academy of Sciences.

The Taung Child was found in Taung, South Africa in 1924 and described by RaymondDart of Wits University. Dart described a cast of the interior of the Taung Child’s skull asbeing proof that the fossil was an intermediate form between humans and apes. The TaungChild was described as “the missing link.” The description was based on the brain structureof the fossil that indicated a high a high degree of expansion of the prefrontal lobe. Theprefrontal lobe is known to be the locus of many of the behaviors that are distinctivelyhuman.

Holloway and colleagues performed the rst high-resolution CT scans on the TaungChild’s skull. The fossil is thought to have been a child of three to four years of age. TheCT analysis does not indicate that any development that is even near human exists in theTaung Child fossil. Comparison of known hominin fossils and chimpanzees to the TaungChild also support the claim that this is not a human ancestor.

The research leaves a gap in human evolution. The developmental features of humanskulls and brains do not have a direct link between humans and apes that has been found inthe fossil record. Dart has been proven to be wrong. Dart did not have the equipment thatis available today and he may have wanted to be famous. Those who will opt to make theclaim that evolution is a fabrication based on this new research must also prove that allother hominin fossils, Neanderthals, and Devonians never existed.

CT scans show Australopithecus africanus not as ‘human’ as thought

https://yeahstub.com/ct-scans-show-australopithecus-africanus-not-as-human-as-thought/

(01) A. sediba | The Smithsonian Institution's Human Origins Program

Australopithecus sediba

Where Lived: Where Lived: Southern Africa (South Africa)

When Lived: When Lived: Between 1.977 and 1.98 million years ago

The fossil skeletons of Au. sediba from Malapa cave are so complete that scientists can seewhat entire skeletons looked like near the time when Homo evolved. Details of the teeth,the length of the arms and legs, and the narrow upper chest resembleearlier Australopithecus, while other tooth traits and the broad lower chest resemblehumans. These links indicate that Au. sediba may reveal information about the origins andancestor of the genus Homo. Functional changes in the pelvis of Au. sediba point to theevolution of upright walking, while other parts of the skeleton retain features found inother australopithecines. Measurements of the strength of the humerus and femur showthat Au. sediba had a more human-like pattern of locomotion than a fossil attributed toHomo habilis. These features suggest that Au. sediba walked upright on a regular basis andthat changes in the pelvis occurred before other changes in the body that are found in laterspecimens of Homo. The Australopithecus sediba skull has several derived features, such asrelatively small premolars and molars, and facial features that are more similar to those inHomo. However, despite these changes in the pelvis and skull, other parts of Au. sedibaskeleton shows a body similar to that of other australopithecines with long upper limbs anda small cranial capacity. The fossils also show that changes in the pelvis and the dentitionoccurred before changes in limb proportions or cranial capacity.

The combination of primitive and derived traits in Australopithecus sediba shows part ofthe transition from a form adapted to partial arboreality to one primarily adapted tobipedal walking. but the legs and feet point to a previously unknown way ofwalking upright. With each step, Australopithecus sediba turned its foot inward with its

Australopithecus sediba | The Smithsonian Institution's Human Origins Program

http://humanorigins.si.edu/evidence/human-fossils/species/australopithecus-sediba


weight focused on the outer edge of the foot. This odd way of striding may mean thatupright walking evolved on more than one path during human evolution.


History of Discovery: History of Discovery: The rst specimen of Australopithecus sediba, the right clavicle of MH1, was discoveredon the 15 of August in 2008 by Matthew Berger, son of paleoanthropologist Lee Bergerfrom the University of Witwatersrand, at the site of Malapa, South Africa. It wasannounced in Science in April 2010.

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

Since Au. sediba was discovered recently, there are many unanswered questions aboutit. Below are some of the still unanswered questions about Australopithecus sediba thatmay be answered with future discoveries:

What is the time range and geographic range of Australopithecus sediba? This questioncan only be answered by the finds of more specimens.

Will the close relationship between Au. sediba and Homo be con rmed by futurefinds? The first paper:

Berger, L.R., de Ruiter, D.J., Churchill, S.E., Schmid, P., Carlson, K.J., Dirks, P.H.G.M.,Kibii, J.M., 2010. Australopithecus sediba: A New Species o f Homo-Like Australopithfrom South Africa. Science 328, 195-204.

th




Other recommended readings:

Balter, M., 2010. Candidate human ancestor from South Africa sparks praise and debate.Science 328, 154-155.

Dirks, P.G.H.M, Kibii, J.M., Kuhn, B.F., Steininger, C., Churchill, S.E., Kramers, J.D.,Pickering, R., Farber, D.L., Mériaux, A.-S., Herries, A.I.R, King, G.C.P., Berger, L.R.,2010. Geological setting and age of Australopithecus sediba from Southern Africa. Science328, 205-208.

Wong, K., 2010. Spectacular South African skeletons reveal new species from murkyperiod of human evolution. Scienti c American 8 April 2010 (Available athttp://www.scientificamerican.com/article.cfm?id=south-african-hominin-f... (link isexternal), 9 April 2010).

Wong, K., 2010. Fossils of our family. Scientific American June 2010.

How They Survived: How They Survived:

The possible increasing emphasis on upright walking is accompanied by di erences in theskull and teeth compared with other australopithecines. The relatively small dentition ofAu. sediba may signal a dietary change. As more features of the environment andfunctional morphology of Australopithecus sediba are discovered, their way of life willbecome clearer.

Due to the mixture of derived features in the pelvis and primitive features in other areas ofthe skeleton, it is unclear to some researchers the extent to which Au. sediba used arborealhabitats or remained on the ground using terrestrial bipedal locomotion. Relatively longarms and a small body may have allowed Au. sediba to utilize arboreal habitats. Derivedfeatures in the pelvis and the pattern of diaphyseal strength in the humerus and femursuggest that Au. sediba might have regularly walked upright in a way that was more similarto modern humans than to earlier members of Australopithecus.


http://www.scientificamerican.com/article.cfm?id=south-african-hominin-fossil



Evolutionary Tree Information: Evolutionary Tree Information:

Australopithecus sediba’s mixture of primitive traits found in other australopithecines andderived traits also found in Homo makes the evolutionary position of Au. sediba aninteresting question. Similar to other australopithecine species, Au. sediba is small in size,with long arms and small cranial capacity. Its features are more derived than those of Au.anamensis and Au. afarensis. Australopithecus sediba bears a strong resemblance to Au.africanus, a fossil species that is also found in South Africa. They have similar skull, facialand dental features. The species di er in features such as the shape of the cranium and theface, showing that Au. sediba was more derived compared with Au. africanus. Thecombination of similarities and di erences led Berger and his colleagues to conclude thatAu. sediba was descended from Au. africanus. The traits Australopithecus sediba shareswith Homo may indicate a closer relationship between this species and Homo than

between other australopithecines and Homo. Berger and his colleagues proposed that Au.sediba is ancestral to the genus Homo or is closely related to the ancestral species. However,there are earlier and contemporaneous fossils attributed to Homo, making it di cult tothink of Au. sediba as an ancestor to Homo. The time range for the species Au. sediba iscurrently unknown. It is not known where in that time span the current sample falls andhow it ts with the time ranges of other species. Another possibility is that Au. sediba isclosely related to another, still unknown species that was ancestral to the genus Homo.While that species evolved into Homo, Au. sediba may have persisted leading to theoverlap in time between Homo and Au. sediba. Other researchers question the idea thatAu. sediba and Homo are closely related at all, citing the possibility that the juvenile MH1may not re ect the adult post-cranial characteristics of Au. sediba or that the postcranialfeatures of Au. sediba may not be unique to the taxon, but may be found in otheraustralopithecines. Another possibility raised by researchers is that the Malapa nds belongin the genus Homo. The number of di erent ideas about the placement of the Malapa

nds stems from the debate on how early members of the genus Homo should berecognized and which fossils belong in it. There is a question of whether cranial and dentalfeatures or the advent of modern postcranial body proportions are most important inde ning Homo, since some fossils, such as the Australopithecus sediba remains, contain acombination of features.



(02) Australopithecus sediba - Australian Museum

The latest new hominin species to be announced has scientists hotly debating its validity asa species and its relationships to other hominins, in particular its relationship to our genusHomo.

Background of discoveryAge

This fossils of this species date to 1.95-1.78 million years ago. This does not represent thetimespan for this species, merely a point in time for a limited number of fossils.


The rst specimen was a right clavicle (collarbone) discovered by Matthew Berger, the 9-year-old son of palaeontologist Lee Berger, in Malapa, South Africa in August 2008.

Subsequent excavations in the cave deposits uncovered two partial skeletons. These werefound close together and it is likely that they died about the same time and were entombedin sediment before their remains had fully decomposed.

On the basis of a combination of primitive and derived characteristics of the skull andpostcranial, the discoverers announced it as a new species in the journal Science in April2010. More fossils are in the process of being excavated.

Key specimens:

Malapa Hominin 1 (MH1): this is the type specimen or holotype. It is considered tobe a juvenile and is represented by a partial cranium (UW 88-50), partial lower jaw(UW88-8) and postcranial elements including a right clavicle (UW 88-1). The secondmolars are erupted and it is considered to have reached about 95% of adult brain size. MH2: probable female adult represented by partial lower jaw (UW 88-54), isolatedteeth from the lower jaw (UW 88-54) and some partial postcranial elementsincluding most of the right arm, ankle and knee joints and bits of the pelvis andshoulder blade. This is the species paratype (a specimen other than a type specimenthat is used for the original description of a taxonomic group)

Australopithecus sediba - Australian Museum

https://australianmuseum.net.au/australopithecus-sediba


Distribution

All known specimens have been found at Malapa in South Africa. Malapa is about 15kmfrom sites of Swartkrans and Sterkfontein.

What the name means

Australopithecus, means ‘southern ape’. It is based on ‘australo’, a Latin word meaning‘southern’ and ‘pithecus’, a Greek word meaning ‘ape’. The name was originally createdjust for this species found in South Africa but several closely related species now share thesame genus name.

The word sediba means ‘fountain’ or ‘wellspring’ in the seSotho language.

Relationships with other speciesDue to the age and overall skeletal features, the discoverers believe this species descendedfrom A. africanus. It also shares derived features with early Homo, more so than any otheraustralopithecine species, suggesting that it is possibly ancestral to Homo (or a sister groupto a Homo ancestor). Although the discoverers favour A. sediba being ancestral to Homo,they also accept that it may be an evolutionary dead end.

The origin of Homo and its direct ancestor among austropithecines is widely debated andremains unresolved. If this interpretation of the fossils is correct, these remains add to thedebate by suggesting that Australopithecus africanus should again be considered a possibledirect human ancestor. A. africanus was once believed to be a direct ancestor butnumerous nds in the later 1900s caused many scientists to push it to a side branch in ourevolutionary family tree.

Many other palaeontologists consider the ‘A. sediba’ fossils to be a chronospecies of A.africanus – meaning that the slight anatomical di erences between the new fossils and A.africanus are due to changes over time within a species rather than them being fromdifferent species. This view makes the fossils merely an interesting side branch of our familytree but does extend the time range for A. africanus by almost half a million years.




Key physical featuresThis species is distinguished from others by a combination of primitive and derivedfeatures rather than single identifying characteristics (autapomorphies). A number offeatures suggest close relationships to A. africanus and possibly Homo.

Body size and shape

similar to other australopithecines in body size and shape, standing about 1.2 metres tall

Brain:

relatively small brain size estimated at about 420cc shapes of the right and left brain halves was uneven, as in Homo

Skull:

minimal cresting compared to earlier australopithecines cranial vault is similar in shape to A. africanusface lacks the pronounced aring zygomatics (cheekbones) of A. africanus but isotherwise generally similar in appearance derived facial mask due to the arrangement of the brow ridge, prominent nose, nasalridge, eye sockets and less-flared cheekbones small cranium with transversely expanded vault slight postorbital constriction weakly arched supraorbital torus (browridge)




Jaws and teeth:

overall, jaws and teeth display features generally similar to A. africanus lacks extreme postcanine megodontia of A. garhi and Paranthropus species and teethare more similar in size to Homo species relatively closely spaced premolar and molar cusps as with other australopithecines jaw protrudes less than with earlier australopithecines the front of the lower jaw is nearly vertical and has a slight bony chin compared to A.africanus teeth di er from A. africanus in having weakly de ned buccal grooves of the uppermolars and smaller postcanines. These features are more derived towards Homo moderately developed canine fossa parabolic dental arcade relatively thick tooth enamel

Limbs:

features are similar to other australopithecines relatively long upper limbs with large joint surfaces retention of primitive features on upper and lower limbs numerous features of hip, knee and ankle indicate this species was bipedal foot bones were primitive and like other australopithecines hands are curved like other australopithecines but more compact

Pelvis:

similar pelvis to other australopithecines but with derived features in the ilium thatanticipate the reorganisation of the pelvis and limbs as seen in Homo ergaster (AfricanHomo erectus)




LifestyleCulture

There is no evidence of tool use or any other cultural elements. It is likely that this specieslived in a manner similar to A. africanus and was adapted to a similar ecological niche. Itprobably used simple tools such as sticks found in the immediate surroundings andscavenged animal bones. Stones may also have been used as tools, however, there is noevidence that these stones were shaped or modified.


The woodland environment of South Africa started to dry out about 2.5 million years ago,leading to the spread of savannah grasslands. A. sediba lived in a generally at landscapewith a patchwork of grasslands and woods.

Numerous bones of other animals were found in the cave deposits, including saber-toothed cats.

Although no detailed analysis has as yet been carried out on tooth wear or isotopes, it islikely that it ate fleshy fruits, young leaves and perhaps small mammals or lizards.

Fran Dorey , Exhibition Project Coordinator Last Updated: 20 January 2011




(03) Australopithecus sediba Essay | Becoming Human

Australopithecus sediba

The most recent addition to the hominin family tree is Australopithecus sediba, namedfollowing discoveries made in South Africa at Malapa Cave. “Sediba” is a Lesotho wordmeaning “fountain” or “wellspring.” Au. sediba is dated to between 1.78 and 1.95 millionyears ago (ma) using biochronology (a relative dating method utilizjng fossilized non-hominin animals)), paleomagnetism (observing the record of Earth’s magnetic eldpreserved in magnetic minerals), and uranium-lead (a radioisotoic method that measuresthe amount of uranium that has decayed to lead in a geologic sample) techniques. Au.sediba has associated cranial (the skull minus the lower jaw) and postcranial (the skeletonminus the skull) remains showing a mosaic of primitive (shared with the ancestral form)and derived (di erent from the ancestral form) characteristics. This mosaic of featuressuggests links between Au. sediba and other species in the genus Australopithecus as well assimilarities to species in the genus Homo. Au. sediba is important because it providesinsights into hominin variation around the period when the genus Homo emerged.

The skull and dentition of Au. sediba display a mosaic of primitive features—in this case,similarities to other species in the genus Australopithecus—and derived features—in thiscase, features more closely resembling species in the genus Homo. Cranially, the featuresthat link it to Australopithecus include a small cranial capacity (around 420 cubiccentimeters), pronounced brow ridges, and enlarged tooth cusps (the pointed eminenceson teeth) spaced close together. The discoverers of Au. sediba argue that, among theaustralopith species, it most closely resembles Australopithecus africanus, which they argueis its likely ancestor. Many differences between Au. sediba and Au. africanus, however, areevident; for example the brain case of Au. sediba is much more vertical on its sides, thetemporal lines (which mark the attachment of a chewing muscle that closes the jaw) arewidely spaced, its cheek bones are smaller, and its molars are long relative to their width. These features not only set apart this new species from other australopith species, but alsolink Au. sediba to species in the genus Homo.

The postcranial remains of Au. sediba, like the cranial and dental remains, show a mosaicof primitive and derived features. The body proportions of this species, for example, arelike

Australopithecus sediba Essay | Becoming Human

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(03) Australopithecus sediba Essay | Becoming Human

australopiths, in having retained relatively long arms, with somewhat elongated legs.The arm also retains large joint surfaces, which suggests this species retained some treeclimbing ability. The shape of the pelvis, on other hand, is derived and resembles that ofHomo erectus, in that the Au. sediba pelvis shows evidence of reorganization associatedwith energy-e cient bipedal walking and running like that seen in H. erectus (see essay onH. erectus for details on its anatomy).

The scientists who discovered Au. sediba suggest this species is a transitional form betweenAu. africanus and the genus Homo. This has been criticized by other scientists who pointout that the earliest dates for the genus Homo are around 2.4 ma (Homo rudolfensis. Thispredates Au. sediba by about 500,000 years, making it impossible all populations of earlyHomo descended from Au. sediba. . Additionally, some African H. erectus are dated toaround 1.8 ma, only about 100 ka younger than Au. sediba, with features so derived that itis very unlikely that this species gave rise to them. These scientists suggest Au. sedibarepresents the termination of the Au. africanus line in South Africa and did not contributeto the genus Homo.

Because of the mix of primitive and derived features present in Au. sediba, scientists debatewhether it should be attributed to the genus Homo or to the genus Australopithecus.Some scientists argue that because Au. sediba shares traits with members of the genusHomo not found in any australopiths species, it should be assigned to Homo. Others,however, argue rather than by individual traits, a genus should be de ned by its overalladaptive strategy (how it moves around, acquires food, uses cognition, etc.) These scientistsplace Au. sediba within the genus Australopithecus because it retains a relatively smallbrain and primitive traits associated with climbing adaptation seen in other australopiths.This debate is an important one because, if Au. sediba is retained in the genusAustralopithecus, its similarities to that genus might suggest it is a transitional species,perhaps transitional to a separate, South African Homo lineage. If Au. sediba is reassignedto the genus Homo (which is unlikely), it may instead represent a relatively early species inthe genus and would suggest that at least some early Homo populations maintained veryprimitive postcranial skeletons and small brains, while possessing skulls that were otherwisevery similar to later Homo species.

Australopithecus sediba Essay | Becoming Human

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(04) Fossils Link Apes, First Humans?

Australopithecus sediba had human-like face and could walkwell upright but was apelike in other ways.By Ken Than, for National Geographic NewsPUBLISHED April 10, 2010

An Australopithecus sediba skull bears both human and ape traits.

Photograph courtesy Brett Eloff and Lee Berger

Identi ed via two-million-year-old fossils, a new human ancestor dubbed Australopithecussediba may be the "key transitional species" between the apelike australopithecines—andthe first Homo, or human, species, according to a new study.

Fossils Link Apes, First Humans?

http://news.nationalgeographic.com/

http://news.nationalgeographic.com/news/2010/04/100408-fossils-australopithecus-sediba-missing-link-new-species-human/


"We've never seen this combination of traits in any one [early human species]," studyleader Lee Berger told the journal Science, where the new study is published today.

Found in the remnants of an underground cave network in South Africa, the partialAustralopithecus sediba skeletons are believed to be from a roughly 30-year-old womanand an 8- to 13-year-old boy.

The pre-human pair, who may or may not have been related, apparently fell to their deathsinto a chasm littered with corpses of saber-toothed cats and other predators.

The new species may be the wellspring—"sediba" in the local Sotho tribal language—fromwhich our ancestors flowed, the report suggests.

Berger, of the University of the Witwatersrand in Johannesburg, conjures a di erentmetaphor.

"It's the opinion of my colleagues and I that [Australopithecus sediba] may very well be theRosetta stone that unlocks our understanding of the genus Homo," Berger said in astatement, referring to the artifact that helped decipher ancient Egyptian hieroglyphics.

A. Sediba Fossils Suggest Human-Like ApeA. Sediba Fossils Suggest Human-Like Ape

Growing to just over 4 feet (1.2 meters) tall, A. sediba has a number of key traits that somewould say mark it as an early human, like Homo habilis, which many consider the rsthuman species.

A. sediba, for example, had long legs and certain humanlike characteristics in its pelvis,which would have made it the rst human ancestor to walk—perhaps even run—in anenergy-e cient manner, the study says. (Related: "Did Early Humans Start Walking forSex?")




Also, A. sediba's face had small teeth and a modern—rather than chimpanzee-like—nose,the study says.

And as in humans, the shapes of A. sediba's left and right brain halves—discernible fromindentations on a remarkably preserved skull—appear to have been uneven.

A facial reconstruction is in the works, and many people will be surprised by how humanthe new fossil species looks, Berger predicted in a press conference Wednesday. "Whatyou'll see, I suspect, is something surprisingly more modern than we would expect in ...other things that have been called Australopithecus," which translates to "southern ape

So if our newest evolutionary ancestor is so human-like, why doesn't the new study classifyit as human?

Berger's team believes that certain apelike traits force the new species into theAustralopithecus genus, or group of species.

For one thing, unlike human species but like other australopithecines, A. sediba had a verysmall brain. The fossil species also had long ape-like arms with primitive wrists that werewell suited for climbing trees.

Australopithecus Sediba's WorldAustralopithecus Sediba's World

In what's now South Africa, A. sediba lived in a patchwork of grasslands and woods, wherethe fossil species likely ate fleshy fruits, young leaves, and perhaps small animals.

The generally at landscape was broken up by small hills and cli s, some of whichcontained caves, which could apparently be treacherous.

Scientists speculate that a harsh drought may have driven two desperately thirsty membersof A. sediba to enter one of these caves in an attempt to nd an underground source ofwater.




The pair may have clambered partway down into the cave, only to slip and fall severalyards to their deaths. The deathtrap also contained fossils of 25 species that lived alongsideA. sediba, including potential predators such as saber-toothed cats, hyenas, and wild dogs.

A. Sediba Only Human After All?A. Sediba Only Human After All?

Other anthropologists seem to be unanimously excited about the new human-ancestorfossils. But not everyone is so sure the new species is the "key transitional species" betweenprehistoric apes and humans suggested by the study.

"I don't think there's a lot of compelling evidence to suggest that [A. sediba] lies betweenAustralopithecus and Homo," said anthropologist Bernard Wood of George WashingtonUniversity.

A. sediba "doesn't t what our preconceptions would be about the ancestor of Homo,"said Wood, who wasn't involved in the study.

For example, A. sediba's arms are too long—too apelike—and the species isn't as welladapted for upright walking as some scientists expect the direct ancestor to the rst humansto be, Wood said.

Also, at 1.95 to 1.78 million years old, the A. sediba fossils simply aren't old enough torepresent an ancestor to Homo, said anthropologist Brian Richmond, also of GeorgeWashington University. (Explore a prehistoric time line.) "It's hard to argue this is the ancestor of Homo when it's occurring much later than theearliest members of the genus Homo by half a million years," Richmond said, referring toan early fossil of H. habilis that dates back to 2.3 million years ago.

Anthropologist William Kimbel thinks this chronological conundrum could be resolvedby calling the new specimens Homo instead of Australopithecus.




"By putting it in Australopithecus and saying it's ancestral to Homo, you're left withhaving to wonder how to accommodate earlier Homo [species]," Kimbel said.

"If you put it in Homo, that problem falls away," he said. "It's then just one of severalspecies around two million years ago that are near the base of the Homo lineage."

Susan Anton, an anthropologist at New York University and a joint editor of the Journalof Human Evolution, agreed.

A. sediba has so many similarities with Homo that "I think they might have been better oincluding it in Homo," Anton said.

"If you do that, then this is really no longer a transitional species between Australopithecusand Homo. It is Homo"—and just an evolutionary dead end in human ancestry.

With Fossils, Timing Is EverythingWith Fossils, Timing Is Everything

Berger, who has been funded in the past by the National Geographic Society, maintainsthat A. sediba belongs with other australopithecines because its anatomy suggests it was stillclimbing trees. (The National Geographic Society owns National Geographic News.)

"It hasn't made that grade-level shift to the genus Homo" yet, he said.

As for questions about its timing, Berger believes future discoveries could turn up A.sediba fossils that are hundreds of thousands of years older, which would make them oldenough to be the ancestors of early Homo species.

"This [discovery] site is only a point in time. It doesn't represent the rst appearance of thisspecies, nor will it probably represent the last," he said.




Regardless of where A. sediba ends up in the human family tree, it's already an importantfossil precisely because of all the questions that it raises, said paleontologist Scott Simpsonof Case Western Reserve University in Cleveland, Ohio.

"This fossil is not one that resoundingly answers any speci c questions," Simpson said."What it does is reinforce the idea that we haven't even asked all the appropriate questionsyet.

"People are going to be discussing this for a long, long time."



http://evoanth.files.wordpress.com/2013/04/mh1.png

(05) Australopithecus sediba: human by accident?

Australopithecus sediba, everyone’s second favourite Australopith after Lucy, was back inthe news last week as more research on this fascinating specie was published. Firstdiscovered in South Africa in 2008, the species made headlines when preliminaryinvestigations revealed that they were a mixture of earlier ape-like (Australopith) andmodern traits (Homo). This raised the intriguing possibility that we’d discovered the “apeman” (or ape woman, if you prefer) from which the more modern-looking species evolved.

MH1; one of the Australopithecus sediba skeletons found

Australopithecus sediba: human by accident?

http://www.evoanth.net/2013/04/16/australopithecus-sediba-human-by-accident/


Such hopes were short lived however, as it was discovered Au. sediba was ~1.9 millionyears old (Pickering et al., 2011). Since the rst members of Homo lived 2.3 million yearsago (Aiello and Wells, 2002), Au . sediba obviously couldn’t have been their ancestor(unless they had a Delorean. That always leads to weird family relations). Some maintainthat the earliest members of Homo don’t actually belong to our genus, and that it actuallyevolved much later (Wood and Collard, 1999). If this is the case then Au. sediba could stilltake center stage in the story of our evolution.

At the very least Au. sediba appears to be closely related to the ancestor of Homo, even ifthey aren’t that ancestor themselves. As such they can provide valuable insights into theorigins of our genus. Now the initial investigations have been completed and published,revealing how Australopithecus sediba moved, what they looked like and where they t inour evolutionary tree (Berger, 2013).

These results con rm our earlier suspicions that Au. sediba had a mixture of ape-likeAustralopith and more modern Homo traits (when wanting to sound fancy, scientistsrefer to such a mixture as a “mosaic”). For example, they had a cone shaped rib-cage likeAustralopiths and modern apes (compared with our barrel shaped rib cage). However, thebottom of this rib-cone is much less slender than it is in an ape, being more similar to thehuman rib cage (Shmid et al., 2013).

The hand of sediba, with short stubby human-like fingers

Other such mosiac traits include the arm. This research showsthat shoulder blade was orientated upwards (like an ape), sosediba would look like they were shrugging their shoulders.Such an orientation makes it easy to reach over their head, sotheir really long arms (again, like an ape) could grab ontobranches (Churchill et al., 2013). However, whilst apes andearlier Australopiths have long curved ngers to “hook” ontobranches, Au. sediba‘s ngers are short and stubby (Kivell et al.,2011). This is a human adaptation to better handle tools.




Currently we only know of one species of Australopith that used stone tools; so thisdiscovery suggests it may have been a lot more widespread than we thought.

Almost every aspect of Au. sediba‘s anatomy has a similar mix of modern and old traits;from the jaw through to their backbone. Put them all together and you wind up withsomething that looks like the image below. De nitely an ape-like Australopith, but withsome key modern traits (Berger, 2013).

A modern human (left); sediba (middle) and chimp (right)

However, what I nd them o s t interesting are those traitsunique to sediba, not present ineither other membersof Australopithecus or Homo . Mostnotably this includes sediba‘s way ofwalking. Although they werebipdeal, like other Australopiths andhumans (with many similaradaptations), an analysis of theirlower limbs reveals they walked withtheir feet twisted slightly outwards.No other member of our family

walks like this (DeSilva et al, 2013).

This unique way of walking has led some of the researchers involved in these new papers tosuggest that Australopithecus sediba may not be as closely related to modern humans asearly research suggested. They claim that sediba may have split from the human lineage


http://evoanth.wordpress.com/2013/01/03/did-australopithecus-make-stone-tools/



millions of years earlier, before even Lucy lived (Schmid et al., 2013)!

A possible reconstruction of the human family tree, taking these new ndings intoaccount

If this is the case then it would mean that all their human-like adaptations were the result ofconvergant evolution. That there were multiple lineages independently evolving towardsthe modern human body plan. Perhaps this speaks to just how well adapted our form is forlife in Africa. It also raises the fascinating possibility that had things played out a littledi erently there may have been another genus of tall, upright, smarthominins. Remember that Neanderthals, for all their di erences, are still classi ed as thesame genus as us. Imagine if a completely di erent genus of intelligent hominins haddeveloped!

Although that’s a fascinating possibility, not all the researchers agree with it. Irish et al(2013) point out that some of sediba’s traits – such as the shape of their teeth – are sosimilar to Homo that it’s very unlikely both groups evolved them coincidentally. Theirdetailed analysis of sediba’s location in the human family tree place them much closer tohumans; indicating both us and them developed from southern Australopiths, likeAustralopithecus africanus. This shows that the emergence of Homo was more complexthan we thought, with multiple lineages emerging from our ancestors.

In short, this research shows that Australopithecuses sediba was the mosaic we thought itwas. However, it’s unique features force us to change where we place it in the humanfamily tree and by doing so we revolutionise our understanding of the entire course ofhuman evolution; either by showing another lineage of hominins existed that wasdeveloping human-like traits coincidentally, or revealing the genesis of our genus was a lotmore




complicated than we thought. This is the nal nail in the co n of the idea that Au.sediba was the ancestor of modern humans, but frankly I am not disappointed. The ideaswhich replace it are just revolutionary.

Aiello, L. C., & Wells, J. C. (2002). Energetics and the evolution of the genus Homo. Annual Review of Anthropology, 323-338.

Berger, L. R. (2013). The Mosaic Nature of Australopithecus sediba. Science,340(6129), 163-165.

Churchill, S. E., Holliday, T. W., Carlson, K. J., Jashashvili, T., Macias, M. E., Mathews, S., … & Berger, L. R. (2013). The upperlimb of Australopithecus sediba. Science, 340(6129).

Irish, J. D., Guatelli-Steinberg, D., Legge, S. S., de Ruiter, D. J., & Berger, L. R. (2013). Dental Morphology and the Phylogenetic“Place” of Australopithecus sediba. Science, 340(6129).

Kivell, T. L., Kibii, J. M., Churchill, S. E., Schmid, P., & Berger, L. R. (2011). Australopithecus sediba hand demonstrates mosaicevolution of locomotor and manipulative abilities. Science, 333(6048), 1411-1417.

Pickering et al, (2011). Australopithecus sediba at 1.977 Ma and implications for the origins of the genus Homo. Science 333, 1421

Schmid, P., Churchill, S. E., Nalla, S., Weissen, E., Carlson, K. J., de Ruiter, D. J., & Berger, L. R. (2013). Mosaic Morphology inthe Thorax of Australopithecus sediba. Science, 340(6129).

Wood, B., & Collard, M. (1999). The human genus. Science, 284(5411), 65-71.

As an aside, I predict young earth creationists will respond to these ndings by 1. playingup the ape-like nature of the ape/human mosaic traits and 2. using the fact that it’srelationship to humans is being re-evaluated to question whether it – and otherAustralopiths – is related to humans at all. They may also use the fact that rst impressionswere wrong to question the validity of palaeoanthropology all (together)



(06) A famous 'ancestor' may be ousted from the human family | Science

This skull may have grown up to look more like an australopithecine than a human-likemember of our genus Homo - Brett Eloff/Courtesy Profberger and Wits University

A famous 'ancestor' may be ousted from the human familyA famous 'ancestor' may be ousted from the human family

By Ann Gibbons, April 23, 2017

NEW ORLEANS, LOUISIANA—NEW ORLEANS, LOUISIANA—A remarkably complete skeleton introduced in2010 as “the best candidate” for the immediate ancestor of our genus Homo may just be apretender. Instead of belonging to the human lineage, the new species of Australopithecussediba is more closely related to other hominins from South Africa that are on a sidebranch of the human family tree, according to a new analysis of the fossil presented herelast week at the annual meeting of the American Association of Physical Anthropologists.

A famous 'ancestor' may be ousted from the human family | Science

http://www.sciencemag.org/news/2017/04/famous-ancestor-may-be-ousted-human-family


When fossils from several individuals’ skeletons were found in a collapsed cave in Malapa,South Africa, in 2008, their discoverer, paleoanthropologist Lee Berger of the Universityof the Witwatersrand, noted that they helped fill a key gap in the fossil record 2 million to 3million years ago when some upright-walking australopithecine evolved into the earliestmember of our genus, Homo. But the oldest Homo fossils, at 2.4 million to 2.9 millionyears, are scrappy, and a half dozen more primitive hominins may have been walkingaround Africa at roughly the right time to be the ancestor. Researchers have hotly debatedwhether their direct ancestor was the famous 3.2-million-year-old fossil Lucy and her kind,Australopithecus afarensis from Ethiopia, or another australopithecine.

With its fossils dated to 1.98 million years ago, Au. sediba is too young to be directlyancestral to all members of the genus Homo. But Berger and his colleagues proposed in2010, and again in 2013 in six papers in Science, that given the many humanlike traits inAu. sediba’s face, teeth, and body, the Malapa fossils were a better candidate than Lucy orother East African fossils to be ancestral to Homo erectus, a direct human ancestor thatappeared 1.8 million years ago.

In a talk here, though, paleoanthropologist Bill Kimbel of Arizona State University inTempe analyzed the most complete skull of Au. sediba and systematically shot down thefeatures claimed to link it to early Homo. Kimbel noted that the skull was that of a juvenile—a “7th grader”—whose face and skull were still developing. In his analysis, withpaleoanthropologist Yoel Rak of Tel Aviv University in Israel, he concluded that the childalready showed traits that linked it most closely to the South African australopithecine Au.africanus, a species that lived in South Africa 3 million to 2.3 million years ago. And had itsurvived to adulthood, its humanlike facial traits would have changed to become evenmore like those of Au. africanus.




For example, the breadth of the young Au. sediba’s cheekbones appears narrow, as in earlyHomo. But by studying other australopithecine, ape, and Homo fossils to see how featuresof the cheekbones change as individuals grow and chewing muscles develop, Kimbel andRak could predict how the boy’s face and skull would have looked if he’d grown up to bean adult. The resemblance to Au. africanus is so striking, in fact, that Kimbel thinks Au.sediba is a closely related “sister species” of Au. africanus—and not a long-lost humanrelative. “We don’t believe … that Au. sediba has a unique relationship to the genusHomo,” says Kimbel.

Other researchers who have long been skeptical that Au. sediba was an ancestor of Homofound Kimbel’s talk persuasive: “Spot on,” says paleoanthropologist Bernard Wood ofGeorge Washington University in Washington, D.C. Paleoanthropologist Ian Tattersall ofthe American Museum of Natural History in New York agrees with Kimbel that Au.sediba is most closely related to Au. africanus and that neither species is ancestral to earlyHomo.

But paleoanthropologist Darryl de Ruiter of Texas A&M University in College Station, aco-author with Berger on the 2013 paper describing the skull, says he and his formergraduate student reached “the opposite conclusion” when they used computationalmethods to project how the skull would have changed as it matured. “I disagree with hisimpression that the changes that [the skull] would have undergone had it lived toadulthood would be so extensive as to make it appear like Au. africanus,” said de Ruiter,who heard Kimbel’s talk.

The only way to know what an adult Au. sediba’s skull and face really looked like, he says,is to nd one: “The ultimate resolution of the question must await the long-hoped-forrecovery of the adult cranium of Au. sediba.”



(01) australopithecus anamensis | the smithsonian · genus australopithecus and early fossil...

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