1 / 37

CH 32 - Outline

CH 32 - Outline. Evolution of Primates Mobile Limbs Binocular Vision Evolution of Early Hominids Evolution of Later Hominids Evolution of Early Homo Modern Humans Human Variation. Evolution of Primates. The evolution of primates is characterized by trends towards: Mobile limbs

francisdodson
Download Presentation

CH 32 - Outline

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CH 32 - Outline • Evolution of Primates • Mobile Limbs • Binocular Vision • Evolution of Early Hominids • Evolution of Later Hominids • Evolution of Early Homo • Modern Humans • Human Variation

  2. Evolution of Primates • The evolution of primates is characterized by trends towards: • Mobile limbs • Grasping hands • A flattened face • Binocular vision • A large, complex brain, and • A reduced reproductive rate

  3. Primate Diversity

  4. Primate Diversity Prosimians Prosimians are a type of primate that include lemurs, lorises, bushbabies, and tarsiers, but not monkeys, apes, or humans (simians). They are considered to have characteristics that are more "primitive" than those of monkeys and apes. Prosimians are the only primates native to Madagascar, and are also found in Africa and Asia. 4

  5. New World monkeys differ slightly from Old World monkeys in several aspects. The most distinction is the nose, which is the feature used most commonly to distinguish between the two groups. The scientific name for the New World monkeys, Platyrrhini, means "flat nosed". New World monkeys are the only monkeys with prehensile tails—in comparison with the shorter, non-grasping tails of the anthropoids of the Old World. New World Monkeys

  6. Old World Monkeys Old world monkeys are more closely related to apes than new world monkeys

  7. The Old World monkeys are native to Africa and Asia today, inhabiting a range of environments from tropical rain forest to savanna, shrubland and mountainous terrain, and are also known from Europe in the fossil record. Old World monkeys are medium to large in size, and range from arboreal forms, such as the colobus monkeys, to fully terrestrial forms, such as the baboons. Old World Monkeys

  8. Apes: African, Asia, and Human?

  9. Mobile Limbs • Hands and feet • Most primates have flat nails • Sensitive pads on the undersides of fingers and toes • Many also have both an opposable big toe and thumb • Mobile limbs and clawless opposable digits allow primates to freely grasp and release tree limbs

  10. Evolution of Primate Hand

  11. Binocular Vision • Stereoscopic vision • Depth perception • Allows primates to make accurate judgments about distance and position of adjoining tree limbs

  12. Binocular Vision

  13. Primate Characteristics • Opposable thumb • Nails instead of claws • Single births • Binocular vision • Expanded, complex brain • Emphasis on learned behavior

  14. Evolution of Primates • Prosimians were the first type of primate to diverge from the human line • Surviving anthropoids are classified into three superfamilies • New World monkeys • Old World monkeys • Hominoids

  15. Evolution of primates

  16. Evolution of Primates

  17. Evolution of Hominids • Proconsul is believed ancestral to hominids • Phylogenetic tree indicates humans are most closely related to African apes • Genetic changes used as a molecular clock to measure relatedness of different groups • Last common ancestor appears to have lived about 7 mya

  18. Monkey SkeletonCompared to Proconsul Skeleton

  19. Hominids • Hominid fossils: • Must have an anatomy suitable for standing erect and walking on two feet • Bipedalism • Skeletal differences between humans and apes largely because: • Humans are bipedal, while • Apes are quadrupedal

  20. Adaptations for Standing1. Location of spine in skull2. Human spine is S-shaped; ape spine is curved.3. Human pelvis is bowl shaped; ape pelvis is long and more narrow.4. Humans femur angle in towards the knees; ape femurs angle out.5. Human knees can support moreweight than ape knees.6. Human foot has an arch; ape foothas no arch.

  21. Australopithecines • Australopithecines: • Evolved and diversified in Africa 4 mya • Possibly a direct ancestor of humans • Southern Africa • Australopithecus africanus • Eastern Africa • Australopithecus afarensis

  22. Human Evolution

  23. Australopithecus afarensis The specimen was discovered in 1974 at Hadar in the Awash Valley of Ethiopia’s Afar Depressionby Donald Johansson of the Cleveland Museum of Natural History Lucy is estimated to have lived 3.2 million years ago.[ The discovery of this hominid was significant as the skeleton shows evidence of small skull capacity akin to that of apes and of bipedal upright walk akin to that of humans Providing further evidence supporting the view that bipedalism preceded increase in brain size in human evolution

  24. Australopithecus afarensis Named “Lucy” after the Beatles song “Lucy in the Sky with Diamonds” Several hundred pieces of bone representing about 40% of the skeleton

  25. Evolution of Early Homo • Homo habilis • Dated between 2.3 and 1.4 mya • May be ancestral to modern humans • Skulls suggest portions of the brain associated with speech were enlarged • Ability to speak may have led to hunting cooperatively and the advent of culture

  26. Homo erectus • Homo erectus and similar fossils • Found in Africa, Asia, and Europe • Dated between 1.9 and 0.3 mya • Larger brain and flatter face than Homo habilis • Much taller than previous hominids • Thought to have first appeared in Africa and then migrated into Asia and Europe • First hominid to use fire

  27. Homo ergaster

  28. Evolution of Modern Humans • Most researchers believe Homo sapiens evolved from Homo erectus • Multiregional Continuity Hypothesis • Similar evolution occurred in many different places • Out-of-Africa Hypothesis • H. sapiens evolved from H. erectus only in Africa, and thereafter migrated to Europe

  29. Evolution of Modern Humans Which of these makes more sense and why?

  30. Neanderthals • Neanderthal (H. neanderthalensis) skeletons were first discovered in Germany’s Neander Valley • Skeletons date back 200,000 years • Massive brow ridges with protruding nose, jaws, and teeth • Heavily muscled • Culturally advanced • Manufactured variety of tools

  31. Neandertals

  32. Cro-Magnons • Oldest fossils to be designated H. sapiens • Modern humans who entered Asia and Europe from Africa 100,000 years ago • Made advanced stone tools • Accomplished hunters • Hunted cooperatively • First to have language

  33. Cro-Magnons

  34. Human Variation • Hypothesized that human variations evolved as adaptations to local environmental conditions • Bergmann’s Rule - Animals in colder regions of their range have a bulkier body build • Allen’s Rule - Animals in colder regions of their range have shorter limbs, digits, and ears • Comparative study of mitochondrial DNA • Suggests human populations have a common ancestor no more than a million years ago

  35. Ethnic Groups

More Related