Physical Anthropology by George Bales

Skull ID Project

Skull Identification Project

Brother George Bales, C.F.A. University of Missouri-St. Louis

Physical Anthropology 1005 Lab Session: Monday 12:30-1:30 p.m. Dr. Pamela Ashmore December 7, 2009

Skull ID Project

This fossil cast’s field identification number

is KNM ER 1813 and it was discovered in 1973 by Kamoya Kimeu in Koobi Fora,

Kenya (Smithsonian Natural History Museum [SNHM] Homo habilis, 2009).

Homo habilis is the

taxonomic identification given to this species of hominin and it is commonly referred to as the “handy man,” although it is thought to be a female. The name was given to the first specimen found by the Leaky team in Olduvai Gorge, Tanzania because stone tools were found in the same geologic location with the fossils. The tools are known as Oldowan tools or “pebble tools.” The ability to make tools, a behavior, is what the Leaky team decided separated Homo habilis from other hominins, thus, placing the species into the genus Homo (SNHM Homo habilis, 2009). It is certain that Homo habilis lived between 2.3 to 1.5 mya. Interestingly, Homo habilis is contemporaries with another hominin species called Homo rudolfensis. There is a lot of debate to whether the two should be considered separate species (SNHM Homo habilis, 2009). Homo habilis also lived at the same time as the Australopithecines. Homo habilis fossils have been found in East Turkana, Kenya, Tanzania, Ethiopia, and South Africa.

Homo habilis

occupied the east and southern regions of the African continent. The estimated cranial capacity of Homo habilis is 680cc. Interestingly, the cut off was between 700cc to 800cc to be considered in the genus Homo. The Leaky team lowered this number to 600cc (SNHM Homo habilis, 2009). Homo habilis has expanded frontal and parietal regions and a more rounded occipital as compared to earlier hominins.

Homo habilis has

reduced alveolar prognathism as well. Furthermore, Homo habilis has a parabolic dental arcade with larger anterior teeth corresponding to posterior pre molar and molars. In other words, there

Skull ID Project

is an absence of postcanine megadontia (Kreger Homo habilis, 2009).

Although there is less

sexual dimorphism with Homo habilis, it is still more than in later hominins. It is certain that habilis is bipedal and has a precision grip in order to make tools. It is apparent that there is digital shortening and the hallax is larger and fully abducted. There is definite thickening of the metatarsal shaft with a human-like cross-sectional shape (Kreger Homo habilis, 2009). Culturally, it is believed that Homo habilis lived in structures that were constructed on the ground. They are believed to be the first hominins to create tools. It is debated whether they were actually hunting or whether they were scavenging. Most likely, they were taking the leftovers from other predators’ kills. It is believed that Homo habilis was the first hominin to leave Africa. This fossil cast’s field number is identified

as KNM WT 17000 and it was discovered on August 29, 1985 by Alan Walker in

West

Turkana,

aethiopcus, 2009).

Kenya

(SNHM

Paranthropus

It is believed to be a male

specimen. Paranthropus aethiopcus is the taxonomic identification given to this

species of hominin. Paranthropus aethiopicus was extant between 2.4 to 2.6 mya and overlapped with Australopithecus africanus, Homo rudolfensis, and Homo habilis.

This

specimen is commonly referred to as the “Black Skull” because of the dark color of the fossil which is due to the high manganese content of the matrix it was embedded within. It is a complete fossil of a “robust” early human (SNHM Paranthropus aethiopcus, 2009). Specimens

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have been found at sites in the East African Rift Valley, West Turkana, Kenya, and Omo, Ethiopia. Paranthropus aethiopicus’ brain capacity was not much larger than that of a modern chimp at 410cc (SNHM Paranthropus aethiopcus, 2009). Well under the cutoff set for genus Homo. Interestingly, Paranthropus aethiopcus’ cranial morphology is unique in that it has adaptations for heavy chewing. That is to say, “the prominent sagittal crest running along the midline at the top of the skull is the largest ever discovered in the human lineage” and the flaring zygomatics, which are the bones that arch around the side of the skull to join below the eyes and the saggital crest are all adaptive for chewing tough, hard, and fibrous material (SNHM Paranthropus aethiopcus, 2009). It has a v-shaped jaw which is one reason discovers decided it was different than other robusts. There is not much written about the post cranial morphology of Paranthropus aethiopcus or about the cultural behavior because not enough fossils have been discovered in order to draw better conclusions.

This fossil cast’s field identification number is KNM ER 1470 and it was discovered in Koobi Fora, Kenya by

Bernard Ngeneo in August of 1972 (SNHM Homo rudolfensis, 2009).

It is thought that

KNMER 1470 is a male specimen (Kreger Homo rudolfensis, 2009). Homo rudolfensis is the taxonomic identification given to this species of hominin. Homo rudolfensis was extant 2.4 to 1.8 mya and overlapped with Australopithecus africanus, Homo habilis, Paranthropus aethiopicus, and Paranthropus boisei.

Skull ID Project

Specimens have been found at sites in the East African Rift Valley. Koobi Fora, Kenya. Homo rudolfensis’ brain capacity was 750cc (SNHM Homo rudolfensis, 2009). Interestingly, Homo rudolfensis has a slight supraorbital torus across the forehead with no depression or sulcus. There is some post orbital constriction. The species has a much longer face than Homo habilis and the frontal bones of the cranium show that the species has a larger brain consisting of early frontal lobe growth (Kreger Homo rudolfensis, 2009). There is a lack of a crest and heavy muscle markings and the occipital is smoothly rounded. The dental morphology of Homo rudolfensis consists of broader molar crowns as opposed to the narrower molar crowns of Homo habilis. Moreover, the teeth are squared and some teeth are double rooted (Kreger Homo rudolfensis, 2009). The lack of postcranial remains makes an assessment of body size very difficult to measure, although due to the size of the teeth, it is thought to be bigger than Homo habilis (Dorey Homo rudolfensis, 2009). There is no evidence from archeological digs of Homo rudolfensis making tools; however, they were living at a time when other species were making tools. It is possible that these hominins were using Oldowan tools as well (Dorey Homo rudolfensis, 2009). This fossil cast’s field number is NG 6 and

it was discovered between the years 1931 and 1933 by C. ter Haar and GHR von

Koenigswald in Ngandong, Java (SNHM Homo erectus, 2009). Homo erectus is the taxonomic name given to this species because when the first fossil was discovered in Indonesia in 1891 by a Dutchmen who was looking for the “missing link,” he decided to call it the upright man to play on the fact it was bipedal (Dorey Homo erectus, 2009).

Skull ID Project

“[Homo erectus] lived between 100,000 and 1.6 million years ago, although some estimates extend this to between 35,000 and 1.8 million years ago” during the Pleistocene era (Dorey Homo erectus, 2009).

Homo erectus was alive at the same time as Paranthropus

robustus, Paranthropus boisei, Homo heidelbergensis, Homo neanderthalensis, and Homo sapiens. Traditionally, all the fossils found in Asia, Africa, and Europe were considered Homo erectus; however, now, paleoanthropologists consider the specimens from each geographical location different species. Namely, the fossils from Asia are identified as Homo erectus with those in Africa being Homo ergaster and those in Europe being Homo heidelbergensis. Homo erectus’ brain capacity is large at 600cc to 1250cc with an average of 984cc; however, it is still smaller than anatomically modern humans. The face of Homo erectus was large with a massive supra orbital torus, and a broad flat nose. The skull was flattened and elongated with occipital angled with pronounced nuchal muscles. Homo erectus’ cranial bones are thick with a distinct saggital keel shape. The mandible is large and thick without a pointed chin and the molar teeth have large roots but are becoming more like modern humans (Dorey Homo erectus, 2009). The incisors are shovel shaped at the posterior. The post cranial morphology of Homo erectus is only part of the Chinese fossils and it is thought that Homo erectus is shorter and stockier than anatomically modern humans (Dorey Homo erectus, 2009). The pelvic girdle was narrow and the hind limbs were longer and the fore limbs were shorter like modern humans; however, the “bones were thicker which suggests a physically demanding lifestyle” (Dorey Homo erectus, 2009). “Burnt stones and animal bones, charcoal and ash deposits indicate these people may have used fire about 500,000 years ago but it is difficult to prove whether this use was

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controlled” (Dorey Homo erectus, 2009). Certainly Homo erectus made simple tools such as choppers and flakes but there is not many found in Asia; however, it is thought that many were made from bamboo which does not preserve well like stone tools.

This fossil cast’s field number is OH 5 and it was discovered by Mary Leaky in Olduvai Gorge, Tanzania on July

17, 1959 (SNHM Paranthropus boisei, 2009).

Paranthropus boisei is the taxonomic name given to this “robust” hominin; however, it was originally called “Zinjanthropus boisei” and is still referred to as “Zinj” or the “Nutcracker Man” (SNHM Paranthropus boisei, 2009).

The later name “boisei” is to honor Charles Boise who

funded the dig (Dorey Paranthropus genus, 2009).

Considering the very pronounced saggital

crest running along the top of the skull it is said this is probably a male specimen (Dorey Paranthropus boisei, 2009). Paranthropus boisei lived between 1.0 and 2.3 million years ago at the same time as Paranthropus robustus, Australopithecus africanus, Homo habilis, Homo ergaster, Homo rudolfensis, and Homo erectus.

Specimens attributed to Paranthropus boisei have been

discovered in Ethiopia, Tanzania, and Kenya in East Africa.

Brain capacity was around 520cc

just a little over a chimp brain. Cranial features of Paranthropus boisei are ape-like with a flat forehead and a prominent brow ridge or supraorbital torus above the eye and the face is relatively broad, short, and flat with flaring zygomatics. The massive saggital crest and large mandible helped in chewing a very hard diet. The postcanine teeth or molars were huge compared to the anterior teeth. The large molars also aided in chewing and crushing tough dietary material.

Skull ID Project

Males were a lot larger than the females in this species. The rib cage is “cone-shaped” like the rib cage of apes as opposed to the “barrel-shape” of human rib cages (Dorey Paranthropus boisei, 2009).

However, the legs and pelvis have human-like features that

indicate bipedal locomotion but without the sophisticated stride of humans. The arms are rather long compared to the legs (Dorey Paranthropus boisei, 2009). According to Fran Dorey (2009), the Exhibition Project Coordinator for the Australian Museum, The majority of scientists believe that these species did not manufacture stone tools, but they may have used sticks or unmodified stone to access the tubers or hard nuts that were part of their diet. It has been suggested that these species may have lived in social groups based around a dominant male and several females, similar to modern gorillas (Dorey Paranthropus boisei, 2009). This fossil cast’s field number is

KNM-ER

3733

and

was

discovered by Bernard Ngeneo in

Koobi Fora, East Turkana, Kenya in 1975 (SNHM Homo ergaster, 2009). It is dated to between 1.5 and 1.9 million years old and considered to be a female specimen (Dorey Homo ergaster, 2009). Homo ergaster is the taxonomic identification given to this hominin. Homo ergaster means “workman” and it is named this because large stone tools were found at some of the sites (Dorey Homo ergaster, 2009). “The core group within this species lived between 1.5 and 1.9 million years ago although some classifications include additional individuals that extend their range to between about

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700,000 and 2 million years agoâ&#x20AC;? (Dorey Homo ergaster, 2009). Fossils of this species of hominin have been found in Africa and Eurasia. Important sites include regions around Lake Turkana and Lake Victoria, Koobi Fora, Nariokotome, Olorgesailie, Swartkrans and Dmanisi, Georgia (Dorey Homo ergaster, 2009). The average brain size for this species was around 860 cubic centimeters solidifying it in the genus Homo. The cranium or braincase was domed like modern humans; however, the cranium had a moderate post-orbital constriction unlike modern humans. The face shows some prognathism but not as much as earlier ancestors. A distinct groove is right between the distinct double-arched supraorbital torus and the frontal bone. This species has a human like nose, that is to say, the nose projects outward rather than being flat (Dorey Homo ergaster, 2009). The jaw is short and lightly constructed unlike earlier species, which consequently gives it a flatter, shorter face. There is not a chin like in modern humans and the teeth are intermediate between that of humans and apes, that is to say, the side teeth were much more apart at the back of the mandible than at the anterior position. The canines are modern in that they are short and blunt like humans and the premolars and molars are smaller like human rather than earlier species (Dorey Homo ergaster, 2009). It is thought that the body is taller and slender with longer limbs to maximize cooling of the body from the heat from the intense dry heat. The body might have not had as much hair as earlier species as a consequence of environment and the heat as an adaptation to cool the body with sweating (Dorey Homo ergaster, 2009).

Culturally, Homo ergaster may have used fire

because charcoal, burnt earth and bones that had been burned have been found at sites near fossil remains (Dorey Homo ergaster, 2009).

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This fossil cast’s field identification number is STS 5 and it was discovered by Robert Broom and John T. Robinson on April 18, 1947 in Sterkfontein, South

Africa. It is dated at 2.6 mya and is a female specimen commonly referred to as “Mrs. Ples” (SNHM Australopithecus africanus, 2009).

Australopithecus africanus is the taxonomic

identification given to this species of hominin. The name literally mean “southern ape.”

This species lived between 3.2 and 2

million years ago. The only known specimens have only been found in South Africa (Dorey Australopithecus africanus, 2009). The cranial capacity is on average approximately 480 cubic centimeters. This was small but still relatively large when compared with a modern chimpanzee’s brain. When compared to other species of the same genus, Australopithecus africanus shows some more human like features such as a smaller supraorbital torus and a slightly arched as opposed to flat forehead and of course the spine derived from the center of the skull base rather than from the back of the skull (Doris Australopithecus africanus, 2009).

The mandible and dental morphology are

intermediate of those of humans and apes and earlier species of the Australopithecines. The incisors are smaller and shorter and a diastema between the canine teeth and the adjacent teeth is rarer; however, premolars and molars are still rather large in size (Doris Australopithecus africanus, 2009). Post cranial morphology that is more apelike than human like includes a “cone shaped’ rib cage and long forearms but not as long as the legs. The foot bones show that this species

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walks bipedal and the pelvis is completely adaptive for walking on two legs; however, in comparison to human legs it is not as round and has a narrower birth canal (Doris Australopithecus africanus, 2009). According to Fran Doris (2009) “[this species] probably used simple tools such as sticks found in the immediate surroundings and scavenged animal bones … [and] stones may also have been used as tools, however, there is no evidence that these stones were shaped or modified (Doris Australopithecus africanus, 2009).

This fossil cast’s field identification number is Skhul V and it was discovered by T. McCown and H. Moivus, Jr. on May 2, 1932 in Mount

Carmel, Israel and it is a male specimen dated at 90, 000 years old (SNHM Homo sapiens, 2009). The taxonomic name given to this species of hominin is Homo sapiens, which means “wise human.”

This is the only extant

hominin and is relatively a young species only going back 300, 000 years to the present. This species of hominin is found on every continent on the planet. Fossils of the earliest members of this species, called archaic Homo sapiens have been found in Africa, and modern Homo sapiens have been found in many sites across much of the world (Doris Homo sapiens, 2009). “Homo sapiens living today have an average brain size of about 1350 cubic centimeters which makes-up 2.2% of our body weight (Doris Homo sapiens, 2009). The Homo sapiens skull has a very high braincase and a short base unlike the other species of Homo where the skull is very broad on top. Consequently, there is not any post orbital

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constriction. The nuchal muscles are reduced significantly and the occipital is rounded. The face is small with a protruding nose and the mandible is short and has a chin which results in a vertical face.. The supra orbital torus is very small and the forehead long. The orbits or eye sockets are not round but rather square in Homo sapiens (Doris Homo sapiens, 2009).

The jaw

has a parabolic dental arcade with the teeth arranged with the side rows splayed outwards rather than parallel like in the species early ancestors. The front incisors and canine teeth are a lot smaller than the species early ancestors as well (Doris Homo sapiens, 2009). The archaic Homo sapiens have bodies that are slender with long limbs, which is an adaptation for surviving in equatorial geographical regions. It helped to cool the surface of the skin. More robust builds eventually evolved as population migrated to colder environments and adapted to retain body heat. Culturally, according to Fran Doris, The earliest Homo sapiens had a relatively simple culture, although it was more advanced than any previous species. Rare evidence for symbolic behavior appears about 100,000 years ago, but it is not until about 40,000 years ago that complex and highly innovative cultures appear and include behavior that we would recognize as typical of modern humans today (Doris Homo sapiens, 2009).

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Dorey, Fran. (2009). Homo rudolfensis. Australian Museum. Retrieved December 4, 2009, from http://australianmuseum.net.au/Homo-rudolfensis/

Dorey, Fran. (2009). Homo erectus. Australian Museum. Retrieved December 4, 2009, from http://australianmuseum.net.au/Homo-erectus/

Dorey, Fran (2009). Paranthropus genus. Australian Museum. Retrieved December 4, 2009, from http://australianmuseum.net.au/Paranthropus-species/

Dorey, Fran (2009). Home ergaster. Australian Museum. Retrieved December 4, 2009, from http://australianmuseum.net.au/Homo-ergaster/

Dorey, Fran (2009). Australopithecus africanus. Australian Museum. Retrieved December 4, 2009, from http://australianmuseum.net.au/Australopithecus-africanus/

Kreger, C. David. (2009). Homo sapiens. Archaeology.info. Retrieved December 4, 2009, from http://australianmuseum.net.au/Homo-sapiens-modern-humans/

Kreger, C. David. (2009). Paranthropus aethiopicus. Archaeology.info. Retrieved December 4, 2009, from http://www.archaeologyinfo.com/australopithecusaethiopicus.htm

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Kreger, C. David. (2009). Homo rudolfensis. Archaeology.info. Retrieved December 4, 2009, from http://www.archaeologyinfo.com/homorudolfensis.htm

Smithsonian Natural History Museum. (2009). Homo habilis. Human Origins. Retrieved December 3, 2009, from http://anthropology.si.edu/humanorigins/ha/hab.html

Smithsonian Natural History Museum. (2009). Paranthropus aethiopicus. Human Origins. Retrieved Dec. 3, 2009, from http://anthropology.si.edu/humanorigins/ha/aeth.html

Smithsonian Natural History Museum. (2009). Homo rudolfensis. Human Origins. Retrieved Dec. 3, 2009, from http://anthropology.si.edu/humanorigins/ha/rud.html

Smithsonian Natural History Museum. (2009). Homo erectus. Human Origins. Retrieved Dec. 3, 2009, from http://anthropology.si.edu/humanorigins/ha/erec.html

Smithsonian Natural History Museum. (2009). Paranthropus boisei. Human Origins. Retrieved Dec. 3, 2009, from http://anthropology.si.edu/humanorigins/ha/bos.html

Smithsonian Natural History Museum. (2009). Australopithecus africanus. Human Origins. Retrieved Dec. 3, 2009, from http://anthropology.si.edu/humanorigins/ha/afri.html

Smithsonian Natural History Museum. (2009). Homo sapiens. Human Origins. Retrieved Dec. 3, 2009, from http://anthropology.si.edu/humanorigins/ha/sap.htm

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