EEEB STUDY QUESTION AFTER MID
How to AMHs differ in skull and postcranial skeletal structure from Neandertals? [You can omit dentition]
'classical' western Brain: 1200-1740, avg. 1487cc Skull: long, low football head; bulging at back; occipital bun; thick, double arched brow ridge, large rounded eyes, large nose, midface projection, cheek bones swept back dur to this, inflated cheeks (no canine fossa) and possible differences in inner ear and internal nasal morphology with AMH Dentition: no chin, large anterior teeth and worn down I, retromolar gap, taurodont molars (expanded pulp cavity) PC: shorter, stocky bodies, heavily muscles, likely cold adapted, Male 143 lb, Female 120 lb Anatomically Modern H. sapiens Brain: 1222-1730, avg 1497cc Skull: no football head, shoter, higher, rounder, no bun, masteroid process larger; thinner or absent brow ridge, smaller eyes, smaller nose, flatter midface, cheek bones not swept back, hollowed cheeks (canine fossa present) Dentition: chin, anterior teeth maybe smaller and not worn down, not taurodont moalrs, no retromolar gap PC: modern skeleton, longer, more slender limbs, contrast maybe due to warmer climate
Who is Archicebus Achilles and how does he impact our understanding of early primate evolution?
'original long-tailed monkey'. its impact for separate ancient origin hypothesis on anthropoid origin. the fossil indicates that the tarsier and anthropoid primate groups split before that era, the anthropoid lineage is also at least that old. sharply pointed premolars, adapted for shearing prey. temperature that time was exceptionally high and jungles stretched as far north as the aratic, good time to be a primate. if you retrace primate evolution to its beginning, it is what our ancestors most likely looked like.
How can we use the contrasts between tube-like and ring-like ears in making taxonomic contrasts among fossil and living primates? When it comes to primate fossil record of the Eocene and Oligocene, when can it be used for phylogenetic assessments, i.e., when is it useful as a shared derived trait? Note: There is no known functional significance to these differences; one type does not confer an advantage.
-human ear: tube like ear with passage way -ring like ear: ear membrance right at opening not functioning, just as a trait to distinguish Omomyoid
Today there are three primary hypotheses concerning the phylogenetic status of plesiadapids. Describe each including the data/morphology that supports that view. Which view do you hold and why?
1) not a primate 2) A primate, but maybe an extinct side branch. (this? in between) 3) True euprimate the second view, has primate traits especially petrosal bulla, but not looks like primate at all
What are the ways that we assess variation in a collection of fossils? (Though there are many approaches to this, I ask that you used the list discussed in class).
1. geography 2. sex 3. gender 4. rule out pathology 5. general variation 6. chronological time 7. more than one taxon
What traits do we see in the stem primates from this epoch that convince researchers that they are indeed true or euprimate
1. limbs+locomotion: generalized skeleton, opposable big toe, nail instead of claws, typically aboreal quadrupeds 2. brain and special senses: postorbital bar, snout smaller, eyes more forward, more reliance on vision, more complex thought, more complexity of brain (reorganization) 3. dentition and diet: small, unspecialized incisors: use hands as exploratory tools; broader molars: more fruvigory and folivory arboreal creature realy more on vision than smell and eat fruit and leaf
where has H. erectus (sensu lato) been found? What is the date range for this taxon in Africa? In other parts of the world?
1.8-200,000 BP first found in Indonesia and China, subsequent finds in SA, EA, NA, Europe, India, Georgia --> population migrated from Africa to Java in just 15,000 yrs Indonesia seems to be
What is the time range for the forms known broadly as Neandertals? Where are they found?
130,000-28,000 BP Northern Europe
What is the time range for the forms known as AMHs (Anatomically Modern Humans)
195,000-20,000 BP Africa, Levant, Western Europe
Where were H. habilis (sensu lato) fossils found? When did it live?
2.8/2.77, 2.4/2.33-1.44 EA and SA
What can we say/hypothesize about the life style of most of the australopithecines and even the parathropines in terms of diet and general adaptation to their environment?
20 stone tools at lomekwi 3.3 mya but how important? maybe capable but not have performance, a bit more intelligence?
Where were the Transitionals/Heidelberg fossils found? What is their time range? Name one and share one fact about it that makes it special (to you or in general).
?1.1/1.2-0.9-0.2 Europe? Asia-some think different than what found in africa and europe. Africa ex. Bodo (found in Ethiopia) 600000BP, our defleshed friend
What are some of the problems in drawing a clear distinction between "Asian" and "African" finds? For example, why is the skull labeled OH9 -analyzed by the class—such a problem for a neat geographic split?
A. More Asian looking form in Africa (more variation or more species?) -Bouri (Daka Cranium), Middle Awash, Ethiopia -Ileret Kenya, 1.55 MYA: support for diverse taxon B. odd finds in both Africa and Asia (indication of more variation of or additional taxa) -Olorgesaiille, Kenya -Sambungmacan 3 [SM3]. Java: more variability in Asia fossil OH9 was found in Africa and had 3/4 Asian traits
What are the three broad trends that we use to distinguish the early hominins whom we know well ("our familiar friends") as hominins and not just as other hominoids? Discuss each trend.
A. brain: some relative increase on size, ?reorganization? -400-550 cc, 10% increase on relative brain compare to chimps, position of lunate sulcus is a debate -but 3-4 associations some reorganizations going on B. dentition: less anterior, more posterior, changes in muscle orientation= change in diet -incisor relatively smaller (compare to chimp), canine smaller, premolar and molars larger, canine still somehow pointed and projecting -C/P3 complex semi-horning (smaller C, smaller gap, P3 semi-one), some says no, some says non functioning -muscle move undernearth and chewing more -sexual dimorphism: canine and body size shows high level of sexual dimorphism, some social organization C. Limbs: trend to bipedalism (debated) -adaptation for biped: femur angle in, big toe shorter and non-abductable, pelvis shorter and broader, longer medial condyle, arched foot -adaptation for arboreal climbing: funnel shaped cage, arms longer than legs, some long and curved toes, pelvis flat -forman magnom in between human and chimps
Based on your analysis of the skull, does Au. afarensis look more like a modern human or a chimp? Why?
A. skull -transitional, chimp like-skull, swept back cheeks, prognathic -temporalis set on skull, compound crest (brain smaller bc of compound crest) -unfleshed cranial base B. dentition -smaller C, still project a bit; C/P3 complex smaller, diastema, P3 semi-worn, semi-horning -larger P, M; I relatively smaller -U-shaped Palate even converging in back, retains thick molar enamel -eating hard object C. brain -386-550, avg. 445 D. postcranial bones/locomotion -adaptation for biped and adaptation for arboreal climbing E. misc -4-5.5 ft, high level of sexual dimorphism in between chimp and human... transitional state
Name and discuss each of the three theories that attempt to explain the relationship between Neandertals and AMHs. Which of these do you think is most likely based on the current evidence? Why? Be sure to explain your answer in full considering the data from morphology, culture/lifestyle, and molecular analyses.
A.Out of Africa -We know some hominin left Africa and spread around before them -200000 years ago, only H. sapiens emerge and spread around replacing everybody, intrebreed doesn't matter -H. Neandertholensis and H. Sapiens B. Multiregionalism -Gene flow through global population -Similarities along all population and regional variant (bit of genetic drift but same species) -H. sapiens Neandertholensis and H. sapiens sapiens C. Partial replacement -2% differential mortality, imaging colonization... -Interbreed successfully because they are member of species -H. sapiens Neandertholensis and H. sapiens sapiens I stand for the second one and variations are due to bit of genetic drift in different environments the molecular evidence today shows there was interbreeding and all non-african population show some percentage of Neandertal, denisoran or ither archaic species. (gene flow) stand for B local regional anatomical continuity: we can trace a particular evolutionary trajectory through a suite of anatomical features shared by fossil hominins in a particular region. the occasional appearance of occipital buns in modern human crania, the appearance of a retro-molar gap in some early human fossils, and the general robustness of early European modern human fossils are all evidence of regional continuity in Europe Asia and Australia may provide the best evidence of multiregional evolution. regional characters seen in H. erectus in China and Indonesia are mirrored in modern humans in China and Australia. For example, the high vertical frontal bone of Chinese H. erectus is considered continuous with that seen in Chinese modern humans. The sagittal keel, occipital torus, and supraorbital tori of Indonesian H. erectus are suggested to continue through, in lesser degrees, to modern human Australians. Likewise, the Ngandong hominins are thought to represent morphological and temporal intermediates between H. erectus and some modern Australians
What are the two broad categories of primate forms found in the Eocene? How do they differ? It is fine to use a general statement but then support the aspects of the general statement with evidence from morpholology (e.g., if you say that one was gregarious, what would be the proof?)
Adapoids -example: Adapis, 8.5 oz to 1.5 lbs -general pattern: diurnal, frugivores, small incisor, large canine, gregarious (sexual dimorphism body size and canine size), aboreal quad, some clinger and leaper, ring like ears Omomyoids -example: Shoshonius, Teilhordina 1oz-5lbs -general pattern: insectivores (spiky molar cust), solitary (little sexual dimorphism), mostly vertical clinger and leaper, nosturnal (proportionally large eyes) tube like ears *ears -human ear: tube like ear with passage way -ring like ear: ear membrance right at opening *auditory bulla -not function but this trait to distinguish Omomyoids, it has tube like ear doesn't mean they are ancestral form of tarsiers end of Eocene gets colder, 60% goes extinct, great cut wipe out most forms, enter seasonality
Discuss four contrasts in skull form between the "Asian" and "African" Homo erectus (sensu lato).
African VS. Asian 1. brow: thinner more curving supraorbital brow VS. thicker usually straighter torus 2. slope: less sloping VS. receding forehead and more sloping 3. keel: no keel VS. sagittal keel 4. angle: rounder occipital angle VS. strong occipital angle (African: thinner cranial bones, higher rounder skull; Asian: lower, flatter skull, thicker cranial bones with more superstructure)
Name the other two candidates for earliest hominoid. Why do some researchers think that they are better candidates?
Afropithecus and Morotopithecus Afropithecus: 20-17 MYA. contemporaneous with Pronconsul. The dentition adapted hard foods. large jaws, thick enamel for grinding and crushing. similar to those in the Middle Miocene African definitive hominoids with an increasingly drying climate. Morotopithecus: postcranials of another early Miocene hominoid at Moroto Uganda. 20.6 MYA. contemporaneous with Afropithecus and Proconsul. Dentally similar to Afropithecus, the big change in postcranial bones. the arms were longer than the legs, that the shoulder was suspensory and that the lumbar part of the vertebral column was less flexible. an early hominoid body.
What traits suggest to some that Proconsul is the earliest hominoid? What features raise questions about this for some so that they think he is a derived catarrhine?
Appearance--overall body size, brain, skull, dentition, postcranial skeleton Overall body size: 6 lbs-150 lbs Brain: relatively larger and rounded and more complex. EQ/Allometric brain size is 1.5 that of an equivalently sized monkey. Dentition and diet: resemble ancestor propliopithecids in dental formula and shape of the teeth. 2123 dental formula (the same as all catarrhines) and retain the "simple" Y-5 molars (as opposed to the cercopithecoid biolophodont molars). "dental apes." All had sexually dimorphic C--implying gregarious social behavior. sexual dimorphism. frugivorous, some folivorous Limbs and locomotion: most proconsulids were arboreal quadrupeds with equal arms and legs. as quadrupedal climber with no good living analogy. -Ape-like traits: No tail, the scapula is moving a bit to the back, a bit more flexibility in the elbow and other joints, a small decrease of flexibility in the lumbar region -Monkey-like traits: Hindlimbs are equal or a little longer than the forelimbs. some movement of the scapula toward the back is oriented to support weight underneath. the lumbar region is still long and flexible, the joints are not as flexible as in modern apes, the chest is narrow and deep (instead of broad and shallow as in hominoids)
Several taxa have been found that predate Lucy. What are their names, where and when are they from and how do they impact our understanding of human evolution? (There were several articles on the syllabus about some of these taxa, you might want to draw on one of them as you consider your answer).
Ardipithecus ramidus 4.4-3.9 MYA, EA Australopithecus anamensis 4.2-3.9 MYA, EA
What skeletal features differentiate Au. africanus from its earlier relative, Au. afarensis? [When I ask about skeletal features think about the full range--overall skull, dentition, postcranial skeleton, brain. Don't worry about the specifics of brain size too much, a broad range of 400-550 for all australopithecines is enough. In truth, I view that and height/weight as sprinkles/extras so focus on the core data.]
Au. Afrensis (Lucy) Skull: very prognathic, new skull has compound crest, chimp-like skull, temporalis set back on skull, unflexed cranial base Dentition: I relatively smaller, C/P3 complex less P3 semi-sectorial and small diastema, C smaller and still project a bit, modern size P and M, dental arcade intermediate still close to U-shape and even converge toward back, temporal muscles, retain thick molar enamel Brain: 386-550, avg. 445 PC: adaptation for biped and adaptation for arboreal climbing, relatively long arms and short legs Misc: 4-5.5 ft, 110 lb, high level of sexual dimorphism Au. Africanus Skull: higher rounder cranium, cheeks not swept back, less prognathic than afarensis, no sagittal crest, brow ridges less prominent than afarensis, flexed cranial base Dentition: smaller I, like C, No C/P3 complex, larger P and M Brain: 400-560, avg. 461 PC: bipedal, relatively long arm and short leg
What do Au. and P. stand for when written for the genus name?
Au. Australopithecus P. Paranthropus (robust Australopithecus?)
How do Au./P. robustus and Au./P. boisei differ from each other?
Au./P. robutus: chewer Au./P. boisei: super chewer boisei has everything robutus have but more
For each of the early hominins discussed so far "our familiar friends" try to give the full name, the area where found (EA, SA or CA) and the time range--including the alternatives.
Australopithecus afarensis EA, 4/3.9-3.8/2.9 MYA; Australopithecus africanus SA [3.5],3-2.5/2.0; Australopithecu/Paranthropus aethiopicus EA 2.7-2.5/2.8-2.2; Au./P. boisei EA, 2.3-1.2/1.0; Au./P. robustus SA 2.0-1.5/1.0 MYA
I put several fossil finds under the heading of "surprises, flat faces, and trouble makers." How many of these can you recall including their time range and location. Critically, how to they effect our interpretation of human evolution during the Plio-Pleistocene?
Australopithecus bahreghazalia CA; 3.5-3.0 MYA -From "river of the Gazelles", nick name- Abel Environment mixed: Savannah and woodland. Area once covered in water and woodlands Diet unusual- fed on underground parts of sedges & grasses in savannah Greatest similarities to Au. Afarensis, is it Lucy more widespread or is this a different species? Australopithecus garhi EA; 2.5 MYA -Odd mix: prognathic face, yet large molars, M2 even larger than average Au./P., but not dish-shaped face like robust forms Postcranial bones- if the same individual, more human like proportions legs to arms Found near butchered bones; 3-toed horse dismembered; Antelope jaw- 3 cut markers-tongue sliced out
Two new species of Australopithecus have been announced in the past year. Who are they, were and when are they from and why are they important?
Australopithecus deyiremeda EA; 3.5/3.3 MYA -"Close relative" Au. Afarensis or something else? Dentition suggests different diet than Lucy, more chewing cheeks more forward, large and thick jaw, thicker enamel Others say differences too subtle Discovers suggest it descended from early Au. Afarensis and possibly ancestral to Homo and/or robust forms Australopithecus Prometheus SA; 3.67 MYA -"Little foot" Virtually 90% complete Initial foot- big ankle with arch but divergent big toe For some-settles the debate- they were walking and climbing, for others that conclusion is patently absurd Statues- some say its Au, africanus, just variation. Others say it's something else
What features help us to distinguish hominoids from other anthropoids? Why is there difficulty in talking about shared derived traits for this group?
Bipedalism, relatively large brain, simple molar Y5, longer arms than legs, scapula back less flexibility. no external tail. anthropoids include hominoids for example proconsulids, it is hard to tell whether its early hominoids or derived catarrhines because it has both ape-like traits but also monkey-like traits
What characteristics are used to distinguish the "classic" western European forms? Be sure to include features of the skull (at least 5), dentition and the postcranial skeleton.
Brain: 1200-1740, avg. 1487cc Skull: long, low football head, bulging at back, occipital bun (projecting occipital); thick, double arched brow ridge, large rounded eyes, large nose, midface projection, cheek bones swept back dur to this, inflated cheeks (no canine fossa) and possible differences in inner ear and internal nasal morphology with AMH Dentition: no chin, large anterior teeth and worn down I, retromolar gap, taurodont molars (expanded pulp cavity) PC: shorter, stocky bodies, heavily muscles, likely cold adapted
What is the difference between dating fossil finds from East Africa and those from South Africa?
EA: Great Rift Valley, volcanic activity, K/Ar dating, more woodland SA: limestone caves, relative dating methods, more savannah
What are the ecological changes in the Late Miocene and how does this affect hominoids? Can you name at least one taxon from this time? Using news articles/text/required article from the syllabus, describe this taxon in a haiku.
Ecological and geological context drier more seasonal habitats in both east Africa and SW Asia. It is increasingly dry and cool in East Africa and elsewhere Primate fossils are rare. the type of forest changed so it made life hard for a frugivorous form. We are left with small pockets-refugia The cercopithecids who first appeared earlier will soon undergo their own adaptive radiation, filling the new niches in areas once populated by hominoids. So OW monkeys didn't radiate until AFTER the apes. With their biolophodont molars and ability to adapt to a broader mixed diet in this harsher environment, they would survive and spread. Fossils: Lufengpithecus and Gigantopithecus Lufengpithecus: over 1000 specimens, including crania, mandibles, teeth. Gigantopithecus: 8-.5MYA/ some even say to 300,000 or 200,000 years ago. He survived until 500,000 in China and Vietnam. The finds are all teeth and mandibles. The reconstructed appearance. Estimates on height based solely on finds of jaws and teeth--9 feet tall. 150-230 kg,. a veggie, likely eating tough fibrous foods, perhaps even bamboo. (haki?????)
What happens to hominoids in the Middle Miocene in Europe and Asia? How is this related to aspects of both ecology and geology (for the latter, plate tectonics)? Can you name some of the taxa that appear at this time?
Europe: adaptive radiation -Dryopithecus, Ouranopithecus, later Oreopithecus Ecology and geological context As the African plate drifts north it presses into Eurasia it began to split forming the Great Rift Valley along the red seas through East Africa. Volcanic activity Land bridges around 16 mya allow movement from Africa into Europe and Asia of many forms including the hominoids who moved into the temperate woodland of Eurasia. From 15-10MYA a warm moist period with subtropical environment as far north as central Europe. with no tail and longer arms than legs, and the relatively bigger brain and body: apes-hominoids Examples: our second leading candidate for ancestor to African Great apes and human: Dryopithecus -thinner jaws and thin molar enamel a diet of softer fruit. -Postcranial bones are debated -a shorter vertebral column, a broad chest, a dorsally placed scapula and longer arms than legs Example: Ouranopithecus the third leading candidate for ancestor of African apes and humans. -His face is very reminiscent of a gorilla. -no postcranial bones middle Miocene European radition: specialized ape Oreopithecus (8-7MYA) Asia (south and southwest) 16-7 MYA Sivapithecus ealiest 13most 8-10 MYA -Orang face -the separation of African and Asian hominoid lines took place at least 12MYA--not a split of humans from all great apes but of forms that would lead to orang from forms that would eventually divide lead to chimp/gorilla/human
What are the morphological differences in the cranium and dentition between H. habilis(sensu lato) and H. erectus? (sensu lato). Are there any differences in postcranial anatomy?
H. Erectus (sensu lato) has: Larger brain on average (600-1250, avg 900cc VS. Habilis 500-800/825) Long low flattish skull Most have thick bones and cranial superstructures (though less so most African form) Maximum width low on skull Pentagon view from back Dentition the molar continue to get relatively small Also have difference on body proportion!
ome researchers prefer to call these forms Homo heidelbergensis while others refer to them as archaic Homo sapiens. Still others have decided to leave the matter open for the time being and avoid using formal taxonomic designations so they are referred to as Transitionals or Heidelbergs. What is your opinion and why? (There is no "wrong" answer.)
I will call them one species, because even though the finds have differences, they are found in so many different sites, and I think these are variations becuase of geography. either their dentition, brain, or pc are close to modern human's
What is your perspective on the debate above the issue of variation in early Homo, how do you explain the variability in early Homo--one taxa, two, more than two? And if more than one, who will be ancestral to Homo erectus? Should we even keep the taxon H. habilis? Be specific in your reasoning.
I will put in in two separate 'large' as H. rudolfensis and 'small' as H. habilis sensu lato. beacause there are too many variations and I think geography cannot explain so many variations. Brain: larger brain (600-800 cc, avg. 751) VS. smaller brain (500-671, avg 610) Face: Australopithecus liked face (flat face and wide across middle) VS. homo liked face (wide across supper face and not very flat) Dentition: Australopithecus liked (fairly large M thicker jaws) VS. homo liked (thinner jaw and smaller M narrower P) The 'small' form will be the ancestral because the traits are more human like
Discuss one other new find that either helps to clarify the situation or adds more confusion to the issue of variation in H. erectus (sensu lato). [You can refer to the finds as the experts do, bytheir names or their numbers, e.g., Bouri, Illeret, Olorgesallie, SM3, Dmanisi]
Ileret Kenya, 1.55 MYA: support for diverse taxon
What can you share about the geological and ecological context at the time that the earliest primates are believed to appear (65-90mya)?
K-T Boundary. between the end of Mesozoic and beginning of Cenozoic drastic environmental changes caused or contributed to the extinction of the dinosaurs and generated opportunities for mammals. Massive extinction of dinosaurs open new niches, potential of new niches. a comprehensive replacement of mammals at the K-T boundary. Many of these new mammals are archaic forms that are not traceable to living groups. The Cenozoic began much, much warmer than it is today.
Given what you know of tool making in other animals, primate and non-primate (e.g., birds such as the one in the video posted to the class wiki-in the news) to what extent to you view this as a distinguishing aspects of humans? Are there aspects of human tool making that in your view make it different?
Kanzi: human is not the only tool maker and user
Where do researchers think that the last common ancestor of the African great apes came from? Can you name a candidate from each of the two broad areas?
Kenyapithecus (14/5mya) -larger molars, thicker enamel, stouter jaws -The postcranial bones suggest longer arms than legs and semi-terrestrial terrestrial knuckle-walking. -For some, Kenyapithecus is the first of five candidates for ancestry of African great apes. definitive hominoid with longer arms than legs.
What features from your description led some researchers to hypothesize that this was an early primate? What primate features were lacking in this form that led others to reject that hypothesis?
Lacking: postorbital bar, very much not primate looking, small braincase, orbits face sideways, not use hands as exploratory tool (the use of spikey teeth) Molar teeth primate like -Some insectivore but some fruivior Generalized body, flexible joints (wrists, ankles) The timing is right ?petrosal bulla?
For the last twenty or so years, some researchers have drawn a distinction between Homo habilis (sensu stricto) and Homo rudolfensis. On what basis do they make this distinction (be specific in terms of morphological contrasts) that researchers traditionally have made between the "large" and "small" forms?
Large VS. Small Brain: larger brain (600-800 cc, avg. 751) VS. smaller brain (500-671, avg 610) Face: Australopithecus liked face (flat face and wide across middle) VS. homo liked face (wide across supper face and not very flat) Dentition: Australopithecus liked (fairly large M thicker jaws) VS. homo liked (thinner jaw and smaller M narrower P)
Pick one other method that doesn't fall into the "relative" dating methods category and discuss it to the extent presented in class.
Mitochondrial DNA /mtDNA The key, in mammals, the mutation rate for mtDNA is estimated at 2-4% every million years. If you compare the mtDNA of the two (or more) forms, count up all the differences in mtDNA you can determine how long it's been since they shared a common ancestor.
What are the three possible options as to which stock gave rise to the anthropoids? Which do you think is accurate and why? (there is no "correct" answer to this; experts in the field disagree).
Omomyoid Origin, Adapid Origin, Separate anceint origin -(uses the example of Archicebus achilles 55 MYA China, thought to be the earliest-discovered ancestor of tarsiers, probably at this the tarsier and anthropoid groups spilt apart, the anthropoid lineage is also at least that old. because the tarsier and anthropoid primate groups spilt before the era, sharply pointed P suggest tiny mammal fed on insects, during the era that global T was exceptionally high and jungles stretched as far north as Arctic, it was a great time to be a primate. Second, Beard found the Libyan discovery of a new species of the primate Apidium. he said earlier hypotheses suggested that anthropoids as a group may have evolved in response to the global cooling and drying that occurred at the Eocene-Oligocene boundary. our new research indicates this was certainly not the case, because anthropoids had already for several MYA in Africa prior to that boundary. but the climate change still had a deep impact on anthropoid evolution, because habitat fragmentation and an increased level of allopatric speciation took place as a result. anthropoids, being forest dwellers, would have been particularly impacted by forest fragmentation during the Oligocene.)
What are the epochs of the Cenozoic and what is the time frame for each?
Paleocene 65-55 MYA Eocene 55-34 Oligocene 34-23 Miocene 23-5.3 Pliocene 5.3-2.6 Pleistocene 2.6 MYA-10000 Years ago Holocene 10000-present
How does Homo habilis (in the broad sense) differ from the australopithecines? [Think about the broad categories of overall appearance of the skull, dentition, brain and postcranial bones, brain.]
Skull: higher and rounder, decreased prognathism, bones are thinner (never buttressed nor dish shaped) Brain: 20% increase in relative size, definite reorganization-lunate sulcus posterior, 500-800/825 cc Dentitions; more anterior dentition-relative to posterior, more I, less P and M (never return to C/P3), P narrower, prarabolic dental arcade, dentition even out of anterior/posterior PCs and locomotion: no clear change, foramen magnum relatively centered, evidence for bipedalism: arch in foot, large ankle, non-divergent big toe, but still relatively longer arms than legs
What are the various steps that an organism might go through from burial to discovery as a fossil? What factors might help in the fossilization process, what factors might hinder it?
Taphonomy: from the death of an organism to discovery. Burial, Mineralization and the fossilization process, discovery/exposure. Mineralization and the Fossilization Process -The higher the mineral content, the greater the chance of preservation. fossilization involves replacement of the organic with the inorganic. -Parenthetically can occur with low temperatures, dry winds and lack of oxygen. Discovery/Exposure -Natural erosion processes -Excavation—accidental or intentional
What kind of tools are most closely associated with H. habilis? Can you name the tool tradition, technique, characteristic tool and cultural period to which they belong? What does this suggest to us about their lifestyle—how do we think that they were used?
Technique: hard hammer percussion Characteristic Tool Tool: chopper, unretouched flakes (Oldowan toolkit) Tradition: Oldowan Cultural Period: lower Paleolithic (beginning of stone age) H. habilis early small game hunter, Binford said they are scavengers They use their stone stools to impact their lifestyle. bio-cultural evolution -the dawn of human technology -not unique invent but dramatically changing their world
Try to explain how an understanding plate tectonics, particularly over the last 200 million years, can help us to understand the evolutionary processes and patterns of the forms from this time. In particular, consider the different levels of taxonomic diversity among reptiles and mammalian orders.
The continents were not always in their present positions. Movement of primate in the past; volcano, earthquake., mountain buildings Evolutionary process when plate shifts: gene flow, allopatric speciation; potential to produce great variations
Given you analysis of all of our "familiar friends", what is your opinion as to the phylogenetic relationships among these forms—that is, do the robust taxa form a clade and warrant a different genus name or is this a case of parallel evolution? Explain your reasoning in full.
The first humans (Homo habilis) were contemporaries of the paranthropoids. As a result, they could not be our ancestors. However, it is likely that Australopithecus afarensis and Australopithecus africanus were in our evolutionary line. Australopithecus garhi and/or Australopitheus sediba may also have been our ancestors, though more evidence is needed to settle this question. robust taxa may be a parallel evolution.........
Other than tool making, how, if at all, does the "lifestyle" of Transitionals/Heidelbergs differ from those of earlier hominins (such as H. erectus sensu lato)? Be sure to consider at least four aspects.
They really show they care for children (before are with?) and use fire with hearth. cannibalism! art, pigment around several sites, modern life sexual dimorpism
Who is Carpolestes simpsoni and how/why did he change some views about plesiadapids?
an extinct species of Plesiadapiformes, 56 MYA, which is one of the earliest primate-like mammals appearing in the fossil record during the late Paleocene. C. simpsoni had grasping digits but no forward-facing eyes. Grasping big toe Possibly grasping hand Nail on big toe A recent find: petrosal bulla as a shared derived trait with other primate
And now, the biggie—present and defend your phylogeny for early hominin evolution. Be sure to include all of our familiar friends, two of the finds that push the envelope, two of the "surprises" category and one from the "new friends of Lucy" category. In your response make sure to draw on the specific data noted in class: name, time frame, location (EA, SA or CA) and critically upon appearance (what's happening with the skull, dentition, postcranial bones and if relevant, the brain -though specific cranial capacity (ccs) aren't required, they are a sprinkle). I urge you to start thinking about this now as we'll be adding later hominin in the sessions that follow.
au. afarensis, au. africanus, maybe also from ardi ramidus and au. anamensis, garhi and sediba odd mix, deyiremeda, lucy's friends?
What features suggest that Au. afarensis was a habitual biped? What features raise questions about this? Where do you stand?
biped: big toe nonabductable, toes shorter than in apes, foot with transverse and longitudinal arches, stout heel, longer medial condyle, neck of femur adapted for weight support, femur inwardly angled, large sacroiliac articulation, short broad ilium. climbing: toes more long and curved than in human, strongly developed markings for attachment of flexor muscles, short femur, long radial neck, funnel shaped rib cage, relatively long forelimb, scapula with uptuned articular surface for humerus head. ------in between human and chimp
Other than dentition can you think of any other contrasts between parapithecids and propliopithecids?
body size
What happened to the climate at the end of the Eocene/beginning of the Oligocene and how do you think that the ecological and geological context of the time affected primate evolution?
coldest epoch, dryer, more drought (diet change), forest becomes prairie. N America and Europe separate, Africa separate from Aisa
What is the morphological evidence for the conclusion that two of the families are considered stem/basal anthropoids while the other two are considered stem catarrhines?
dental formula, 2133, catarrhine 2123.
What traits help us to distinguish anthropoids?
eyes move fully forward with orbital closure, more reliance on vision less on smell; fused frontal; fused mandible; rounded molar cusps Fused metopic suture (it's that "Y" shaped line on top of a skull)
Discuss at least three other aspects of what we know about H. erectus use (sensu lato) life styles (e.g, subsistence and the "other" categories from class, e.g., use of fire, life history/development, ?grandmothering", ?care of the elderly?, hair loss, ?art?). [The optional newspaper article packet explores these issues as does your text.]
fire care of the elderly art
Based on your assessment of Au. afarensis and Au. africanus and the "robust" forms, what aspects of the environment and/or diets of these species may explain their distinct cranial and dental morphology?
food source?
How does the cranium of Au./P. aethiopicus, commonly referred to as the black skull, differ from those of Au./P. robustus and Au./P. boisei
have largest sagittal crest (and compound crest), unflexed cranium, primitive chewer'
Do you think that the variation in H. erectus use (sensu lato) warrants a species level distinction? Why? Be specific. You can't be wrong but you have to defend your answer based on the morphology and understanding of how variability in a collection of fossils can be explained. Follow up—how could splitting or lumping be linked to your perspective as to the tempo and mode of evolutionary change for hominins (think of anagensis and cladogensis + stasis).
i think one taxon but variation because of the geography
what do the terms sensu lato and sensu stricto mean?
in a broad sense in a narrow sense
How does the morphology of Transitionals also known as Heidelbergs, contrast with the features used to distinguish H. erectus (sensu lato). Make sure to include features of the skull, dentition, brain and postcranial bones.
larger cranial capacity (1100-1450 avg 1166), 11% increase, full in modern human range The result of increase of brain size-change shape of skull Higher rounder skill Maximum cranial breadth high on skull Rounder occipital, torus reduced (in most) Less prognathic face Molar continues to decrease in size as well as skeleton robusticity, reaches modern human hight comparable to modern Mediterraneans
What tool manufacturing technique and distinct tool type is most closely associated with the "classic" Neandertals? How do these tools differ from those found with earlier forms? Was this tool tradition the same for hominins existing at this time in Africa and the Levant?
levallois tecnique/the prepared core technique. flakes that have been retouched and evidence of hafting during Middle Paleolithic (Europe), Mousterian tradition. Before the transitional uses hard and soft hammer percussion technique and handaxe, retouched flakes BUT also some blades and hafting found in Israel. different cultural period, in Africa predominant forms are scrapers, points.
For each of the five "relative" dating methods presented in class, state the name and discuss the method
lithostratigraphy: study sedimentary types tephrostratigraphy: study the products of volcanic activity biostratigraphy: the principle that rocks containing the same combination of fossil taxa/having many of the same species in common are probably similar in age. Magnetostratigraphy: The Earth's magnetic field has reversed polarity at irregular intervals worldwide. Fluorine dating: If there is a fluorine in the soil, bones exposed to the seepage of ground water will absorb the fluorine. The longer in the soil, the more fluorine incorporated during fossilization.
How many methods in the other major category of dating methods (chronometric) can you name?
mtDNA (Mitochrondrial DNA) Dendrochronology Isotopic methods Electron trapping techniques/solid state physics methods (TL,ESR,OSL) (thermoluminosence, electronic spin resonance, optically stimulated luminescene)
In the last few years there have been finds/analyses that raise questions about dividing early Homo into the two aforementioned taxa. Discuss one of these issues (for example, the suggestion made by the author of your text-Susan Anton--this is included on the handout.
not size but facial shape, the differences in anterior palate, mandible and facial shape, taxonomic names not assigned. Anton argue that brain size, molar size, and facial size cant use to distingusih them
What tool manufacturing technique, and what type(s) of tools and traditions (one will suffice) are associated with the time broadly known as the European Upper Paleolithic?
prepare core tecnique (the punch flaking), blade, burin, Chatelperronian tradition.
What happens to hominoids in the Middle Miocene in Africa? Who appears, who disappears, and how is this connected to changes in climate? Can you name one of the forms that appears and how he may be adapted to this changed climate?
proconsulids decline and Kenyapithecus appears increasingly cooling and drier. a decrease in tropic forests and an increase in woodland in Africa. the decline of the proconsulids and the rise of more advanced hominoids. some forms almost certainly radiated into these more open niches One example: Kenyapithecus (14/5mya) -larger molars, thicker enamel, stouter jaws -The postcranial bones suggest longer arms than legs and semi-terrestrial terrestrial knuckle-walking. -For some, Kenyapithecus is the first of five candidates for ancestry of African great apes. definitive hominoid with longer arms than legs.
What are the four families of anthropoids from the Fayuum presented in class? Can you name a species from each?
proteopithecidae, eg., proteopithecus; parapithecidae, eg., parapithecus; propliopithecidae, eg., propliopithecus; oligopithecidae, eg., oligopithecus
Describe the appearance of Purgatorius (or of plesiadapids in general)
small brains, a prognathic face that projected well in front of their braincase, and small eye sockets positioned on the sides. lacked a postorbital bar. spikey teeth. enlarged incisor. diastema (space between I and P)-not rely on their hands as exploratory tool. Some had claws and lacked an opposable big toe. neck area faces back Insectivorous, nocturnal, solitary. Narrow snout
For the two isotopic/radiometric methods presented in detail in class, describe those methods being as specific as possible. That is, make sure that your explanation including data on the material, whether the method is direct or indirect, the time range, the half-life of the isotope (even though this is off-the-record), what is compared, etc.
some radioactive isotopes decay at a calculable rate. half-life. If you know the decay rate, expressed as a half-life, then you can calculate the time the process began. if you compare the amount of the original isotope left with the amount of the decay product, you can estimate how long the decay has been going on. Example 1: Potassium Argon Dating 40K/40Ar , K/Ar Dating Volcanic, Indirect, 10,000 to the age of the Earth 4.5 billion years You date the volcanic layers called tuffs. Example 2 Radiocarbon /Carbon 14/ 14C Dating Organic, Direct, a few hundred years to about 40,000 years Example 3 Uranium Series Dating / U Series Dating Thorium/Uranium Dating 230/Th/234Uranium Limestone formations, inorganic and organic carbonates. SAA 5,000-500,000 years
What does the term "stem" mean when we refer to stem primates or stem anthropoids?
they are a form that is prior to a split between platyrrhines and catarrhines as we can't identify them as distinctively belonging to either group. These forms can be ancestral to both platyrrhines and catarrhines. [before cercopithecoids and hominoids spilt, after platyrrhines and catarrhines spilt]
what kind of tools did H. erectus use (sensu lato)? Discuss the tradition, technique, characteristic tool(s), and cultural period. Were the tools the same throughout all the areas in which H. erectus fossils were found?
tradition: Achulean technique: hard and soft hammer percussion characteristic tool: handaxe, cleaver, retouched flakes cultural period: Lower Paleolithic subsistence: small game hunting and scavenging (confrontational?), more meat
What are the "standardly stated" tradition, technique, characteristic tool(s), and cultural period of the Transitionals/Heidelbergs. What has changed in terms of our ideas about their tools.
tradition: Achulean technique: hard and soft hammer percussion characteristic tool: handaxe, retouched flakes BUT blades and hafting found in Israel cultural period: Lower Paleolithic subsistence: dramatic change, large game hunters, fruits and nuts, now invested time and energy into making tools other: care for the disabled (children with pathological and brain problems survived) and fire came with hearth, modern levels of sexual dimorphism, and art
What was the ecological and geological context for the Eocene and how might this have affected primate evolution during this epoch?
warmest, tropical environment, gene flow between north America and Europe. As a result of warm climates during the Eocene, increases in plant diversity created new environmental niches favorable for primates. primarily in north america and europe which were joined together.
Who is Saadinius hijanzensis and how does he affect our understanding of early primate evolution? (For example, why would we say that Propliopithecus was an early catarrhine but that Saadinius was a derived catarrhine?)
what that ancestral form might have looked like; a morphotype for the kind of primate from which both cercopithecoids and hominoids might have evolved. s a tube-like ear which makes it a very good catarrhine indeed that's why we call it an advanced stem catarrhine. It's still before the cercopithecoid /hominoid split but it's a lovely catarrhine. which its predecessors lacked, divergent between OW monkey and apes, shows the divergence took later than thought, after? the cercopithecoid and hominoid split
What do the latest molecular analyses suggest about Neandertals and AMHs? How does this impact your ideas as to phylogenetic relationships?
when AMH encounter Neandertal they interbreed and exchange. Out of Africa cannot be supported with this analysis because one condition for this preposition is they dont interbreed. ?
What are the current options in terms of where and when the earliest anthropoids emerged? Can you name one of the candidates?
where: Africa or Asia. When: 35, 40, 45, 50 or older.
Why do researchers agree that the Middle Miocene forms from Africa and Eurasia are definitive hominoids? Be specific in terms of morphological features.
with no tail and longer arms than legs, and the relatively bigger brain and body: apes-hominoids
What are the two broad categories of dating methods? What is one problem with drawing these categories?
"Relative"—only say that the fossil or artifact is older than something or younger than something. With chronometric, you get a number, a specific date/date range Optimally, researchers use as many methods as possible, both "relative" and chronometric. The more validation the better. relative: limited to specific site, stratigraphy, nature can mess up this with volcanic activity, rivers, earthquakes, etc.
