What do the Bones tell us?

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Laureen Hutchinson
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1 What do the Bones tell us?

2 The scientific study of bones. Comes from the Greek word Osteon, meaning bone Sub-discipline of archaeology and physical anthropology, anatomy, forensics etc.

3 Age at death Height/stature Biological sex Health Habits Diet Cause of death Ancestry

4 The human skeleton is divided into two parts Axial Skeleton: skull, thoracic cage, vertebral column Appendicular Skeleton: Limbs and associated bones There are 206 bones in a mature human skeleton.

5 Axial Skeleton: skull, thoracic cage, vertebral column

6 Appendicular Skeleton: Limbs and associated bones

7 Skull: Limbs and associated bones

8 Sutural Bones Flat Bones Sutural bone Sutures Parietal bone External table Internal table Diploë (spongy bone) Irregular Bones Long Bones Vertebra Humerus Short Bones Sesamoid Bones Carpal bones Patella

9 Sutural Bones Small, irregular bones Found between the flat bones of the skull Irregular Bones Have complex shapes Examples: spinal vertebrae, pelvic bones

10 Short Bones Small and thick Examples: ankle (tarsals) and wrist (carpals) bones Flat Bones Thin with parallel surfaces Found in the skull, sternum, ribs, and scapulae

11 Short Bones Carpal bones

12 Flat Bones Parietal bone External table Internal table Diploë (spongy bone)

13 Long Bones Long and thin Found in arms, legs, hands, feet, fingers, and toes Sesamoid Bones Small and flat Develop inside tendons near joints of knees, hands, and feet

14 Long Bones Humerus

15 Sesamoid Bones Patella

17 Pre-Australopithecines (7-4.4 mya) Sahelanthropus Tchadensis - 7 mya Orrorin tugenensis 6 mya Ardipithecus ramidus ( Ardi ) 4.4 mya Australopithecines ( mya) A. anamnesis mya A. afarensis mya A. platyops 3.5 mya A. africanus mya Early Homo (2.5 + mya to present) H. habilis ( Handy Man ) mya H. rudolfensis ( Rudy ) 1.9 mya H. erectus (ergaster/antecessor) A. ghari 2.5 mya A. aethiopicus 2.5 mya A. boisei mya A. sediba 2.0 mya A. rubustus mya H. heidelbergensis H. neanderthalensis H. floresiensis ( Hobbit ) H. sapiens

18 Genus: Australopithecus mya Southern Ape: derived from the Latin word australo meaning southern and the Greek word pithēkos meaning ape.

19 Small size Small brain, small canines Large premolars and molars Bipedal yes! 2 types: Gracile Robust Difference: Bone density, muscle markings, bone size, skull size, teeth strength, etc. Some give the robust their own genus: Paranthropus Your book does, but by no means agreed upon and I m afraid I am once again going to disagree with your book

20 Gracile Robust

21 Sagittal Crest Sagittal Keel Supraorbital Tori Nuchal Torus Zygomatic Arch Supraorbital Torus Zygomatic Arch Nuchal Torus

canines U-shaped dental arcade Ape-like premolars Appears transitional between apes and

22 1. Australopithecus anamensis mya Bipedal Lake Turkana, Kenya/Ethiopia Similar to Ardipithecus Ancestral Traits: Large canines U-shaped dental arcade Ape-like premolars Appears transitional between apes and humans The word anamensis is from anam ; Turkana word meaning lake and is a reference to the ancient lake-side environment once inhabited by this species.

individuals found Laetoli footprints 3.6 mya The famous Lucy 3.

23 2. Australopithecus afarensis mya Laetoli (Kenya) and Hadar (Ethiopia) Best known Australopithecine Over 300 individuals found Laetoli footprints 3.6 mya The famous Lucy 3.2 mya Bipedal, but hands and feet suggest partially arboreal More varied diet less specialized Brain: 430 cc Named for the Afar region where the first fossils were found

24 Most famous A. afarensis specimen 40% complete skeleton Human ancestor Dated 3.2 mya 3 5 tall 70 lbs

26 Walking with Lucy

afarensis Thought to be same species, but further examination showed

27 3. Australopithecus platyops AKA: Kenyanthropus platyops 3.5 mya Known for: Unusually flat face Similar to A. afarensis Thought to be same species, but further examination showed distinct differences Hence the debate new species or whole new genus Lake Turkana Lived in woodland environment

4. Australopithecus africanus (AKA Paranthropus africanus) 3.2-2.5 mya South Africa Robust Australopithecine Possibly gave rise to robustus Height, size similar to A.

28 4. Australopithecus africanus (AKA Paranthropus africanus) mya South Africa Robust Australopithecine Possibly gave rise to robustus Height, size similar to A. afarensis Larger teeth Famous ones: Taung Child Mrs. Ples Find A. africanus and A. robustus at the same time and place Brain: 450 cc Hint: Do NOT confuse africanus with afarensis!

Australopithecus africanus In 1925 Raymond

29 Australopithecus africanus In 1925 Raymond Dart introduced the first Australopithecine ever found The 3.0 my old Taung Child or Taung Baby, as Dart called it, was the first member of the Australopithecus genus discovered Found in Taung South Africa Estimated to be 3 years old

Primitive projection Name means SURPRISE!

30 5. Australopithecus garhi 2.5 mya Middle Awash, Ethiopia Larger teeth than early Australopithecines Face: Primitive projection Name means SURPRISE! Surprising because: Human-like ratio of arms to legs Direct ancestor to Homo? Body gracile, robust-like teeth Hyperdont gracile ( Big teeth gracile ) Evidence of tool use - Oldowan? Brain: 450 cc

31 6. Australopithecus aethiopicus (AKA Paranthropus aethipicus) 2.5 mya East Africa Known as: Black Skull Ultimate in robusticity Chewing MACHINE! Huge posterior teeth Small anterior teeth Thick enamel Related to A. boisei? Brain: 410 cc Aethiopicus is Latin for Ethiopian

4 mya East Africa Olduvai Gorge Hyper-robust Largest

32 7. Australopithecus boisei (AKA Paranthropus boisei) mya East Africa Olduvai Gorge Hyper-robust Largest Australopithecus Holotype Nicknamed Zinj Or Nutcracker Man Originally Zinjanthropus boisei Brain: 510 cc

33 8. Australopithecus sediba Dates ~2 mya More recent than A. afarensis Transition between A. afarensis and H. habilis/h. erectus Clear bipedal pelvis But long arms Retaining arboreal trait Very dexterous hand tool maker? A lot of Homo habilis specimens have been reexamined and reclassified into this species Comparison: A. Sediba 1, Lucy, A. sediba 2

34 Australopithecus sediba Name means source Fairly new find 2008 South Africa- Malapa cave Two specimens in holotype: Juvenile male, adult female Very close to complete skeletons found Brain:~450 cc

9. Australopithecus robustus (AKA Paranthropus robustus) 1.9 1.0 mya South Africa Descendent of A. africanus?

36 9. Australopithecus robustus (AKA Paranthropus robustus) mya South Africa Descendent of A. africanus? Larger, more pitted teeth Robust Sagittal keel, splayed cheekbones, big brow ridges Chewing machine! Brain: 530 cc

37 These are referred to as Paranthropus in your book A. aethiopicus, A. boisei, A. africanus, A. robustus all have: Large faces Massive muscle attachments (up to sagittal crest) Small front teeth Enormous premolars and molars

38 EXTINCTION OF ROBUSTS? Robusts persist for ~ 1.5 million years ( mya) World-wide climate grows colder during this time Grasslands dry out Change may have occurred too quickly for robusts to adapt Completely disappear from the fossil record

39 Date Hominins mya Australopithecus anamensis (gracile) mya Australopithecus afarensis Lucy (gracile) 3.5 mya Australopithecus platyops Flat Face (gracile) mya Australopithecus africanus Taung Child/Mrs. Ples (robust) mya Australopithecus Boisei (robust) 2.5 mya Australopithecus garhi Surprise! (gracile) 2.5 mya Australopithecus aethiopicus (robust) 2.0 mya Australopithecus sediba Source (gracile) mya Australopithecus robustus (robust)

40 Map of where the fossils were found.

41 Remember, this is our best idea of how the lineages play out but this can change with every new find!

42 Abundant Many well-preserved fossils Some with more complete skeletons or abundant body parts Well studied Growing consensus that A. afarensis is potentially the ancestor of all later hominins

43 Major features 1. They are all conclusively bipedal (although not necessarily identical to Homo in this regard) 2. They all have relatively small ape-size brains (at least compared to Homo) 3. They all have large teeth, particularly the back teeth, with thick to very thick enamel on the molars

44 Chimpanzee, quadruped, - feet far apart; femur comes straight out of the hip socket Lucy and the modern human feet close together, femur angles in from hip to knee

45 Footprints found in volcanic tuff Layer of ash from volcano that is cemented by rain Footprints of animals walking through the wet tuff before cemented Definite Hominid footprints Fully bipedal 2 sets One bigger, one smaller Some argue there is even tinier footprints inside the bigger ones Dated absolutely to 3.6 mya Species that made the footprints A. afarensis

46 Laetoli Footprints, found in Tanzania 3.6 mya

47 Hominin footprint from Laetoli, Tanzania, Africa Note the deep impression of the heel and the large toe (arrow) in line (adducted) with the other toes

48 Near Olduvai Gorge in Northern Tanzania 59 footprints of bipedal hominins were found in a now hardened volcanic ash layer These A. Afarensis individuals walked in two close parallel tracks across wet volcanic dust 3.6 mya which hardened over time

49 The A. Afarensis footprints look almost like those of modern humans

50 Bipedalism mya Sahelanthropus - possibly Ardipithecus ramidus yes, but lineage? Australopithecines definitely Increase in brain size mya Genus Homo Development of stone tool technology mya Genus Homo

52 H. habilis H. rudolfensis H. erectus H. ergaster H. antecessor H. heidelbergensis H. s. neanderthalensis H. floresiensis H. sapiens

53 At least one species (maybe two) of early Homo was present in East Africa a little prior to 2.0 mya These developed in parallel with an australopithecine species These hominin lines lived contemporaneously for at least 1 million years after which australopithecines seem to have disappeared forever

54 Compare brain capacity of Homo habilis to Australopithecines and later Homo erectus and Homo sapiens

4 million years ago Found in Olduvai Gorge

55 Homo habilis handy man * African hominin fossils, Dates to million years ago Found in Olduvai Gorge in Tanzania Brain: 600 cc *Latin translation habilis: able or skilled

56 Most primitive of all Homo long arms Short legs Short stature overall 4.5 ft fully grown Smaller face than Australopithecus

57 H. habilis was found with simple stone tools Tools are known as the Oldowan tradition

58 Simple chopping tools made by striking flakes off a rounded stone Gives it a rough cutting edge Capable of cutting animal flesh Requires considerable skill to make Made of lava and quartz

59 Used stone cores and small flakes Flakes for scraping wood, cutting meat, cutting grass stems Stone tools often found with butchered animal bones At Olduvai Gorge, stone tools and animal bones appear to have been brought from farther away

60 If Homo habilis was hunting animals, then we would expect: cut marks on bone first and then carnivore marks second What we see is the opposite

61 H. habilis H. rudolfensis H. erectus H. ergaster H. antecessor H. heidelbergensis H. neanderthalensis H. floresiensis H. sapiens

62 1.9 mya East Africa 1972 Lake Turkana in Tanzania (then known as Lake Rudolf) Its cranial capacity is somewhat larger than H. habilis (775 cc), but more similar to australopithecines in certain facial features Evolutionary relationships between species of early Homo are ambiguous

63 H. rudolfensis Brain: ~775 cc Cranial capacity is one of the main distinguishers between H. habilis and H. rudolfensis Homo size brain, but robust Australopithecinelike teeth (big brain, big teeth)

64 KNM ER 1470 (H. rudolfensis) KNM ER 1813 (H. habilis)

66 In Rudy, see post-orbital expansion compared to Australopithecus Doubling of brain volume ~440 cc (average Australopithecine) to ~775 cc (H. rudolfensis) Less Prognathism (protruding jaw)

67 Which best represents our ancestor? H. habilis has smaller, human-like teeth But also a smaller, australopithecine brain H. rudolfensis has a bigger, human-like brain But also has larger, australopithecine teeth Big debate: which best represents our ancestor? Small Teeth or Big brain?

68 It is difficult to learn anything about the earliest stages of hominin cultural development before the manufacture of stone tools Archaeological record is almost exclusively limited to material culture We can assume that early hominins used tools made of perishable materials, like wood, animal parts, plants, etc., and displayed an array of cultural behaviors even if little evidence remains in the fossil record

69 Multidisciplinary approach: Geologists Survey to locate potential hominin sites Vertebrate paleontologists Survey geological beds containing faunal remains and look for favorable conditions Paleontologists Give approximate ages of fossil sites in the field using faunal sequences Archaeologists Get involved with sites that post-date 2.6 mya to look for material hominin traces - artifacts

70 Gave crucial adaptive advantages to hominins Earliest tools likely made of perishable materials, leave no trace in fossil record Earliest stone tools date to about 2.6 mya, small sharp flakes Hominin bipedalism would have made tools easier to transport

71 Earliest recognized stone tool culture Oldowan tools found primarily in Olduvai Gorge in Tanzania Excavations led by Mary and Louis Leaky

72 1. Assignment 3 requires students to watch a series of three films DURING class, while filling in worksheets for these films. 2. Monday October 31, 2016 Part 1 and first half of Part 2 will be completed. 3. Wednesday November 2, nd half of Part 2 and Part 3 will be completed. 4. Worksheets will be provided in class and MUST be handed in at the end of class to receive a grade. If you do not hand it in at that time, you will receive a zero for the worksheet. 5. If you are absent, you will receive a zero. If you are late, you will only be graded on the sections you are in class for. If you are more than 30 minutes late, you will receive a zero for that worksheet. 6. This is a graded assignment; no discussing or sharing answers. 7. There will be exam questions pertaining to these films. 8. There will be no makeup opportunities for this assignment. Pay attention Fill in the blanks Easy 100%

Lecture 10-1 Early Fossil Hominids: Bipedal Anatomy & Pre- Australopithecines and Australopithecines

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