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Evolution:

Evolution:. What’s all the fuss about? Terms and Ideas you need to know. Understanding Evolution. Evolution is the process of change. A species is a distinct kind of animal…

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Evolution:

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  1. Evolution: What’s all the fuss about? Terms and Ideas you need to know.

  2. Understanding Evolution • Evolution is the process of change. • A species is a distinct kind of animal… • Complex species have developed from simpler species because organisms are always striving to better adapt themselves to their physical surroundings

  3. A species is a distinct classification of a plant or animal Our Place…taxonomy Kingdom, Phylum, Class, Order, Family, Genus, Species Animal, Chordate, Mammal, Primate, Hominid, Homo, Sapiens-Sapiens Some evidence of evolution are homologies and vestigial organs Homologies are structural likenesses between parts of different organisms. Examples: arm = flipper = wing. Vestigial organs are any part of an organism that no longer serves a useful function. Example: human appendix Evidence of Evolution

  4. Jean-Baptiste Lamarck (1744-1829) • First to use the term Biology as we use it today. • Early, first, proponent of evolution. • Evolution governed by natural laws. • Evolution based on the acquisition of acquired traits. • Giraffe has a long neck because it needs to stretch to reach food.

  5. Charles Darwin (1809-1882) • Charles Darwin was an English scientist who advanced the theory of evolution by proposing natural selection. • Conducted his primary research on the Galapagos Islands. • His two most famous books were “On the Origins of Species” and “The Descent of Man”

  6. Animals with certain physical characteristics that help them to survive in their given environment will live longer and produce more offspring. This will lead to that certain characteristic becoming a dominant trait of that species Animals with good “survival equipment” are better “fitted” to live in their physical environment. They will live long and pass this “equipment” on to other members of the species Thus the struggle for existence results in the “survival of the fittest” What is this idea called Natural Selection?

  7. BIOLOGICAL EVOLUTION OK, LET’S SEE. WHERE WAS I??? OH YES…THE BANANA WAS BIG AND VERY YELLOW.

  8. WHAT IS BIOLOGICAL EVOLUTION? • Change in a species over time.

  9. What can trigger these changes? • Mutations • Random acts sometimes you win…sometimes you lose… • Random Genetic Drift • How our genes are passed on. • Gene Flow • Jumping in your neighbor’s pool.

  10. Mutations • A sudden change in the make-up of the gene or chromosome that brings a new trait into existence. • Can be helpful or harmful. • http://www.randommutation.com/darwinianevolution.htm

  11. Random Genetic Drift • When a group passes on it’s genetic code to the next generation not all genes are passed on… • We only have so many offspring but many more genetic combinations between you and your mate. • Peppered Moth…polluted areas vs. unpolluted areas.

  12. Gene Flow • The transfer of hereditary characteristics from one breeding group to another. • People move…animals are imported

  13. Primates are an order of mammals which includes lemurs, monkeys, apes, and humans Where do we separate? Primates

  14. COMMON PRIMATE TRAITS • 5 DIGITS ON BOTH HANDS & FEET • NAILS INSTEAD OF CLAWS • FLEXIBLE HANDS WITH ABILITY TO GRIP • ERECT UPPER BODY • COLLARBONE • SMALL NOSE, NO ACUTE SENSE OF SMELL • USE OF VISION AS PRIMARY SENSE • LARGE & COMPLEX BRAIN • EFFICIENT FETAL NOURISHMENT • LONG PERIODS OF INFANT DEPENDENCY AND LEARNED BEHAVIOR • ADULT MALES ALWAYS PRESENT WITHIN GROUP (HELP IN CHILD REARING).

  15. Trends in Primate Evolution • Larger body size • Increasing brain size or cranial capacity • More upright standing • Living in or near trees • A diet that includes plants and animals • Binocular vision that allows for depth perception

  16. Trends in Primate Evolution continued… • Specialized color vision • A decreasing number of young produced al one time • Longer embryonic and childhood development • Specialized thumb • Increasing lifespan • Growing complexity of social behavior

  17. Differences Between Man and Apes • Humans have the development of more specialized areas in the brain • Humans have a more vertical face plate • Humans have a smaller jaw and more evenly rounded arch • Humans have smaller canine teeth • Humans have smaller molars • Humans have longer lower limbs (legs) and shorter upper limbs (arms)

  18. The biggy…Bipedalism • Bipedalism is erect posture and walking with two feet • Bipedalism was important in developing the ability to hunt and make tools

  19. The World of our... ANCESTORS

  20. Hominids • Hominids are a family of primates which includes all two-legged manlike species, extinct or living • Examples of hominids are erect walking apes, ourselves and our ancestors

  21. The Australopithecines • Means “Southern Ape” • Australopithecus was an erect walking ape that was a member of the hominid family • There were at least 5 kinds of Australopithecines, but probably one was man’s ancestor • Australopithecines lived 5 to 1 million years ago

  22. Lucy • Lucy was an Australopithecus Afarensis • Her skeleton was was discovered by Donald Johanson in Ethiopia in 1974 • She was the most complete pre-human skeleton ever found • Her bones gave many clues about her anatomy, diet and lifestyle

  23. More Discoveries of A. Afarensis Fossils • Footprints at Laetoli • 3.6 mya • Footprints of two creatures formed in fresh lava ash. • 1975 • Mary Leakey • Laetoli, Tanzania • Significance • Height determined by length of stride 4’-4’8” • Confirmed Bipedality by this time • Big toe in line • Heel toe strike when walking

  24. Timeline of Human Evolution

  25. The Evolution of Humans

  26. Louis Leakey and Olduvai Gorge • Dr. Louis Leakey and his wife, Mary , did their fieldwork at Olduvai Gorge, Tanzania • Dr. Richard Leakey, their son , currently does fieldwork in the Lake Turkana region • Louis Leakey is credited with the discovery of Homo Habilis, the first human

  27. Homo Habilis2.3-1.6 mya • “Handy Man” • Homo Habilis was the earliest known species of the genus homo • Probably made tools • Probably scavenged for meat and ate vegetation • Skull was 30% larger than Australopithecines • Brain much more human like in shape.

  28. Homo Erectus1.9-.3 mya • “Erect of Upright Man” • Homo Erectus was the first large brained human • Sometimes called “JavaMan” or “Peking Man”

  29. Homo Heidelbergensis 700-100,000 years ago • The between species. • Features of Homo erectus and Homo sapiens. • Very robust mandible, no chin • Very prominent brow ridge • Increased cranial capacity. • Smaller teeth but bigger than Homo sapiens.

  30. Neanderthal Man 250-30,000 years ago • Homo Neanderthalensis • This species was human , but was probably not an ancestor to modern humans

  31. Neanderthal Man • Neanderthal man had large arms and legs • His brain was actually larger than modern humans, but the language and speech center of the brain was not well developed • Neantherthal man was a hunter who made tools, had primitive language skills and used fire

  32. Homo Sapiens-Sapiens 130,000 years ago-Present • “Thinking Man” • Lighter build in skeleton • Enormous brain capacity • 1300 cc from 400 cc of early Australopithicine. • Early discoveries called Cro-Magnon Man.

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