Human lineage only human chimp last common ancestor

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human lineage only, human-chimp last common ancestor homosapiens are at the end three groups (old to now): early hominids, australopithecus, homo chimpanzees have bigger brow bones and jaw, teeth projecting, brain size: small to big walking: quadrupedal to bipedal with grasping hallux (big toes grasping) to bipedal (walked on knuckles in the past to walking on two feet) teeth: canine for food and male-male competition (multi male and multi female social structure) gets smaller, molars get bigger (more chewing or harder items in diet) Arboreal (tree use): frequent (with grasping big toes and long arms) to some to rare, arms are curved to grab limbs cranial capacity increases from the past, relative brain size increases (relative to your body size) Anthp 2/24 Polydactyly: multiple different mutations and phenotypes. Ex: SHH regulatory mutation, more digits Dating fossils: multiple methods such as C14 dating (carbon dating) or paleomagnetism (date the
basalt) Relative brain size is Encephalization Quotient Brain bigger at 6 than 4 Hox genes genes that make us different than chimps quiz: earth is 4-5 billion years old, lungs in mammals evolved from air bladder of our fish ancestors, earliest hominins had small brains, chimpanzees are not hominins, hominins originated 400-500 mya from Africa, Ardipithecus had grasping toe, Australopithecus had large molars. Chimpanzee: small brain size, quadrupedal walking, large canine teeth, arboreal (tree use) Ardipithecus: early hominins, smallish brain size, bipedal (grasping Hallux)... Chimps = lucy is smaller, thicker, pyramid shaped, australopithecus, arms are relatively longer, feet are facing our, no neck, peramital mid-cage, fingers are curving in, no neck to hang from trees more comfortably, lighter, humans do more endurance running so we are barrel shaped (not pyramid shaped) and our necks are longer chimp has big toe, we had adductive thick big toe, our pelvis is bowl shaped, our fingers are thiner and straight, chimps have curved fingers to grab trees, chimps are bipedal our brain sizes have gotten bigger ape diets (chimps): fruits and leaves, more fibers, more caloric rich, occasional hunting carried their babies females giving submissive grin to beg for food males occasionally hunt for meat simple tool use, using something to open a nut, female chimps reproduce into their
old age, males compete the hardest over older female chimps because they have the most experience taking care of offspring Chimpanzees had ancestor: ouranopithecus, molar, canine, incisor, similar teeth structure, for lots of leaves and fruit early hominins: ape-like diets tougher diet (ardipithecus molars suggest slightly broader diet than chimps), more thicker enamel, Enamel thickness (thin to thickest): chimps and apes—>ardipithecus— >australopithecus—>early form… australopithecus: teeth and diet, fruit, hard objects, nuts and seeds, tubers, plant foods: big molars, thick enamel for chewing australopithecus tools: simple, like apes, digging sticks for tubers or termites, tools

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