CS 184 * Modeling the Evolution of Cognition * Wntr 07

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CS 184 * Modeling the Evolution of Cognition * Wntr 07 Name_______KEY_____________ CS 184 * Modeling the Evolution of Cognition * Spring 11 “Footsteps Through Time” Worksheet Primate Hall - Primate Skulls: Note the “sagittal crests” - You will need to identify a hominid skull (in next room) that also has these. Australopithecus aeithiops (only hominid showing this structure) - What are they for? Attaching major jaw muscles, that allow high-power crushing Also sexually-selected in some species >> larger in males (e.g. sagittal crest in dom male gorilla) - What is the most striking difference in the teeth of humans compared to the other primates? Missing canines! (Much reduced in Ardi, virtually gone in Lucy) - Give two reasons why might this change have taken place? A tough one! Change in diet?? Change in food processing? (But remember, lost well before stone tools or fire!) Change in sexual selection (i.e. Australopithecus did not show common sexual dimorphism seen in many primates, where males were larger - suggests possibly monogamous???) ??? - Skeletons: Describe the differences between a human and a nonhuman primate (NHP) in their… - Pelvic bone. NHP is long and flat, designed to attach large thigh muscles for climbing trees Human is broad, shortened, bowled. Designed to attach gluteus muscles to help hold body upright, & humans (Hominids, since Lucy) no longer have huge thigh muscles Also narrows birth canal, causing mothers to die attempting to give birth to large-headed offspring One adaptation to this: Produce more altricial (less well developed) infants - Knee. NHP legs bowed, upper thigh (femur) bone does not sit directly on lower calf (tibia) bone Human femur and tibia aligned, tibia has broad lat surface for femur to sit on - to support weight. - Spine. NHP spine arched curved, can include (in apes) large phalanges to attach heavy back, arm muscles Human spine more “S” shaped, helps position weight over pelvis Also, the spine enters (underside of) skull at Foramen Magnum which is positioned more to the rear of skull in apes and more toward the center in humans (and was already more central in Ardi!) - Heel. NHP heel bone juts directly behind, parallel with ground Human, heel bone points slightly down, forming an ARCH, making the human foot a more stable support for body weight - Compare the relationship between the pelvis and the femur in the (upright) vervet monkey vs. the human. Monkey’s femurs (thigh bone) attach to the sides of its pelvis In Humans, pelvis sits directly over femurs, so whole body weight rests on legs - How long is a human’s big toe? Not just the 1-2 inches you see from the outside, but 5-7 inches! Most important difference: aligned with other toes (since Lucy) for bipedal walking not climbing - Is it longer or shorter than the human thumb? Longer - … a chimpanzee’s thumb? Longer - …than a chimp’s toe? May be absolutely shorter, but relatively longer compared to other toes Hominid Hall - Why is an ape’s hand, a human’s foot, and a robot’s appendage a good sequence to summarize human cognitive evolution? Something to consider… Timeline: - Using the length of time a species existed as a measure of its success, which hominid was/is the most successful? Homo erectus - Homo erectus overlaps with which other species of Homo? Homo ergaster (at one end of the timeline) and Homo heidlbergensis at the other -…of Australopithecus? Australopithecus boise = Our family tree is a BUSH! Tools - The Tool Box. Date the drawers & name each culture. Describe the differences between their tools. See TIMELINE (Lecture 2 notes) Olodowan Homo habilis ~2.5 - 1.7 MYA Cracked stones with one or more sharp edge Acheulean Homo erectus ~1.6 - 0.10 MYA Bifacial hand axe, disc, etc (Includes symmetry) Levallois Homo neanderthalensis ~0.25 - 0.03 Prep core w/different action than flake edges So, requires a multi-stage process Mousterian Homo neanderthalensis ~0.2 - 0.03 Refined blades, some hafted into spears Stones in drawer only part of tool So requires hierarchical organization Upper Paleolithic Homo sapiens ~0.14 -Ttoday More refined. Many more shapes, functions, Made from various materials Include clear indiv diffs such as artwork Modern Homo sapiens Today Hammers etc: Tools made by other tools! - Are these tools qualitatively or quantitatively different than the ones in the drawers above and below them? WHY? Something to consider… Name_______KEY_____________ Who’s Who? - What is the earliest hominid fossil (name and age) on display here? Ardipithecus ramidus (teeth) ~ 4.4 MYA - What is missing from the museum’s collection re: this species? The recently discovered, quite complete “Ardi” sekeleton! - Lucy: How many skull fragments in Lucy’s remains? - How tall was she? 6 (not counting jaw) ~ 3.5 feet (about = bonobo) - What is her Latin name? - Did she have fur???? Australopithecus afarensis Something to consider… - What is the Latin name of the “Taung Child”? How did she die? What do we know about this species forebrain? Australopithecus africanus Skull was found in an eagle’s nest. It had an expanded frontal pole - “Sort the Skulls”: Where would you draw the dividing line? Something to consider… - “Turkana Boy” was what species? Compare the thickness of his leg bones with that of a species from a colder climate. Homo ergaster (from Africa) Thinner-boned than the more cold-adapted Homo erectus - How many of the shoes on display were made entirely by machine? - How many by both machine and hand? (The real question here to consider is how can you tell human-made from machine made, and how does the fact that so much of what we deal with, learn from/about is machine made influence the way we think and behave…?!!) - How do these relate to what you saw in the Tool Box & why do we care? Something to consider… (Since machines literally SHAPE so much of our lives…) - What does the fossil of the “Old Man of la Chapelle aux Saints” suggest about Neanderthals? Since he was lame, but lived into old age, that there was a societal structure that could support individuals that could not make it on their own. (Did he make other contributions to his group in trade??)Plus, this has implications for the exercise of compassion, empathy, etc. - Compare the (H. sapiens) skull from Israel with the (H. neanderthalensis) skull from France – how do they differ? Nenaderthal has heavy brow ridges, an occipital bun (bulge at the rear of its skull) which housed their larger brains (expanded occipital/visual cortex?), & a shorter stockier physique with heavier bones (suggesting they are adapted to colder climates). - Two types of evidence of “symbolic” culture – which we discussed, in class, as being associated with two distinct species of hominids – are presented together in The Cave. Which type did we discuss in reference to which species? Remember - this is an ERROR! That is, the cave drawings are of the sort made by Homo sapiens (us) but the cave bear skulls (sometimes found separated from the rest of the bear skeleton) were found in Homo neanderthalensis caves, and may indicate some religious significance (?) to those skulls. The error: these two types of findings would NOT be found in the same cave!! - Rub the “Venus”. What do you think that might have meant, 30,000 years ago? Something to consider… Remember, such art (religious artifact?) was from Homo sapiens only! Inventions - Which hominid was the first to control fire? How did this impact on its distribution? Homo erectus Allowed this species to live and adapt to a great many climates all over the world - Check out the Time Tunnel - List your three favorite inventions and the data associated with each. Something to consider… Human Lab - What mutates faster – DNA or mDNA? mDNA (Mitochondrial DNA) - Why does mDNA link us back to Eve but not Adam? Only carried in female cells - Brains: The size of your brain is equal to the size of what other part(s) of your body? About 2 (or maybe 3?) fists - Compare the Frontal Pole on the chimpanzee and human brain. What function is associated with this area? Pinched in chimpanzees, filled-out in humans (and in hominids since about 2.6 MYA (late Australopithecines). Involved in analogies? long-term planning? - Can you see any Asymmetries in the sliced, or whole, human brain? Where? Left hemisphere, Temporal lobe, Planum Temporal (aka Wernicke’s Area) is larger Involved in speech perception - Locate and sketch the Orbital Frontal cortex in a human brain. To what subcortical structure does it connect? Orbital Frontal is the anterior underside of the Frontal Lobe (behind the “orbits” of your eyes) Has extensive connections to Limbic (Emotion/Motivation) System, especially the Amygdala Involved in social strategy, theory of mind, self control, cultural constraint, etc. One of the three major systems that underwent expansion in hominids, along with Mirror System (Frontal + Parietal) and Speech system (Frontal + Temporal) - What does it mean to say that what is unique about humans is not culture, but cultural advance? Other species learn traditional practices from one another (= culture?), but those cultures do not produce a history of artifacts that then become the basis for new invention/innovation. Plus, accumulated artifacts structure what new cultural practices can occur (and be passed on) including using artifacts that you did NOT (or even could not) make (e.g. computer!) - Briefly summarize one piece of contemporary “news” posted in this area. Something to consider… OUTSIDE – What happened to the tools at the hearth? Chaos! .
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