I.Biogeography A.Comparative Anatomy 1.homologous structures, similar 2.Fossil record – similar structures, carbon dating – evolution II.Theories of Evolution

Download I.Biogeography A.Comparative Anatomy 1.homologous structures, similar 2.Fossil record – similar structures, carbon dating – evolution II.Theories of Evolution

Post on 30-Mar-2015




1 download

Embed Size (px)


<ul><li>Slide 1</li></ul> <p> Slide 2 I.Biogeography A.Comparative Anatomy 1.homologous structures, similar 2.Fossil record similar structures, carbon dating evolution II.Theories of Evolution A.Catastrophism large environmental disaster things change B.Lamarcks 1.Inheritance of acquired characteristics (organism changed in its lifetime could pass those changes to offspring) Slide 3 Slide 4 Slide 5 Slide 6 C.Wallace survival of the fittest evolution D.Darwin father of evolution 1858 1.Biological diversity gene pool there is always diversity within a species 2.Fitness traits best suited for survival 3.Natural selection survival of the fittest, best traits will be passed on 4.Artificial selection man selected, domestication 5.Adaptation allows for survival a)Structural anatomy b)Behavioral courtship, hibernation c)Physiological how the body works Slide 7 Slide 8 III.Evidence for evolution A.Radiometric dating carbon 14 dating, radioactive substances break down in half lives decay B.Fossils imprints of structures within rock C.Comparative morphology and embryology development prior to birth 1.Homologous features similar structures, similar embryological development, Ex. bat and bird wings 2. Analogous features similar functions develop differently Ex. bat wings and butterfly wings 3. Vestigial structures: present, no longer needed Slide 9 Slide 10 Slide 11 Slide 12 Slide 13 Slide 14 Slide 15 D.Experimental evidence peppered moths, 2 variations white and gray Trees with birch (lighter bark) And lichen more white moths 1860s coal soot killed lichen trees darken more gray moths 1900s less soot lichen back lighter bark- more white moths Slide 16 Slide 17 I.Change in frequency of alleles how genetic information changes, which traits show up more often II.Five agents in microevolution A.Mutation change in genetic code, lethal, neutral, beneficial B.Gene flow beneficial traits will be passed from generation to generation one population to another C.Genetic drift chance alteration of genes 1.Founder effect species in new environment will favor certain genes 2.Bottleneck cheetah severe reduction in population small population limited gene pool, greater chance for genetic disorders 3.Inbreeding homozygous limited gene pool, greater chance for genetic disorders Slide 18 Slide 19 D.Nonrandom mating(sexual selection) given member of a population is not equally likely to mate with any other given member fittest E.Natural selection 1.Adaptations traits best suited for survival are passed on 2.Fitness best adaptive traits 3.Galapagos finches Darwin 13 finches common ancestor, beak size and shape and Grants study evolution can quickly occur Slide 20 Slide 21 1.Three modes a)Stabilizing selection average most common b)Directional selection change in the environment shift to one extreme or the other c)Disruptive selection splits population into 2 groups Slide 22 Slide 23 Slide 24 Slide 25 I.Species interbreeding populations which produce viable offspring II. Reproductive isolating mechanisms keeps species separate A.Prezygotic prevents sperm from fertilizing egg 1.Mechanical not physically compatible 2.Behavioral behaviors are different, courtship song displays 3. Temporal breed at different times 4. Gamete egg and sperm cannot fuse 5. Ecological different habitats Slide 26 Slide 27 Slide 28 Slide 29 Slide 30 Slide 31 B. Postzygotic 1.Hybrids offspring may not survive or be sterile Slide 32 Slide 33 III. Mechanisms of speciation A.Allopatric speciation of other countries 1.species separated by geography change over time Darwins finches a)Colonization 1 group of finches 13 species new island, the fittest survive b)Genetic divergence over time species change due to adapting to new environment c)Reproductive isolation gene pool is separated from original gene pool changes occur over time d)Competition fittest for environment survive to breed those characteristics to offspring e)Further speciation original species new species Slide 34 Slide 35 Slide 36 B.Sympatric speciation absence of geologic separation, fruit flies, hawthornes, apples C.????Parapatric speciation next to small population on the fringe of a habitat can form its own breeding group Slide 37 Slide 38 IV.Evolutionary change A. Vestigial structures: present, no longer needed B.Coevolution symbiotic relationships mimicry C. Comparative biochemistry chemical makeup, horseshoe crab, blood chemistry same as spiders D. Genetics DNA V. Extinction: death of the last of a species A. Habitat destruction B. Competition Slide 39 CHAPTER 18 SYSTEMATICS: SEEKING ORDER AMIDST DIVERSITY Slide 40 I. Taxonomy A.Linnaeus father of taxonomy, classification system based on homologous structures B.Binomial nomenclature 1.2 term naming system 2.Genus species identification system Homo sapiens, Felis tigris, Felis leo Slide 41 eastern bluebird (Sialia sialis), the western bluebird (Sialia mexicana), and the mountain bluebird (Sialia currucoides)remain distinct because they do not interbreed. Slide 42 C.Domains 1. Archaea- ancient bacteria prokaryotes 2. Bacteria- modern bacteria prokaryotes 3. Eukarya- eukaryotes divided into Animal, Plant, Protist and Fungi Kingdoms D. Kingdoms 1.Animal heterotrophs, multicellular, eukaryote 2.Plant autotrophs multicellular, eukaryote 3.Protist heterotrophs &amp; autotrophs, unicellular, eukaryote 4.Fungi heterotrophs, plant like, multi cellular, eukaryote 5.Monera bacteria and viruses, prokaryotes Slide 43 Slide 44 Slide 45 D.Taxonomic systemHumans 1. KingdomAnimalia 2. PhylumChordatanotochord 3. ClassMammalia hair, mammary glands, give birth to live young 4. OrderPrimate binocular vision, opposable thumb 5. FamilyHominidae walk upright 6. GenusHomoman-like 7. Speciessapienmodern day E. Taxonomic Key systematic way to identify organisms using structures Slide 46 How Many Species Exist? Biodiversity is the total number of species in an ecosystem Between 7,000 and 10,000 new species are identified annually, mostly in the tropics Tropical rain forests are believed to be home to two- thirds of the worlds existing species, most of which have yet to be named Because tropical rain forests are being destroyed so rapidly, species may become extinct before we ever knew they existed Slide 47 The black- faced lion tamarin Researchers estimate that no more than 260 individuals remain in the wild; captive breeding may be the black- faced lion tamarin's only hope for survival Slide 48 The (a) tarsier, (b) lemur, and (c) liontail macaque monkey all have relatively flat faces, with forward-looking eyes providing binocular vision. All also have color vision and grasping hands. These features, retained from the earliest primates, are shared by humans Slide 49 Primates Some of these adaptations were inherited by humans Large, forward-facing eyes with overlapping fields of view (allowed accurate depth perception) Color vision Grasping hands Enlarged brain (facilitated hand-eye coordination and complex social interactions) Slide 50 Oldest Hominid Fossils Hominids include humans and extinct humanlike primates The oldest known hominid fossils are between 6 and 7 million years old Sahelanthropus tchadensis lived more than 6 million years ago Exhibits human-like and ape-like characteristics Slide 51 Slide 52 Oldest Hominid Fossils Ardipithecus ramidus and Orrorin tugenensis lived between 4 million and 6 million years ago Knowledge of these earliest hominids is limited - few specimens have been found The first well-known hominid line, the australopithecines, arose about 4 million years ago Slide 53 Slide 54 The Earliest Hominids The earliest australopithecines possessed knee joints that permitted bipedal (upright, two-legged) locomotion 4 million year old fossilized footprints confirm that early australopithecines sometimes walked upright An upright stance was significant in the evolution of hominids because it freed their hands from use in walking Slide 55 The Australopithecines Several species of Australopithecus have been identified from fossils Australopithecus anamensis Australopithecus afarensis believed to have given rise to: A. africanus A. robustus A. boisei All australopithecines were extinct by 1.2 million years ago Slide 56 The Genus Homo The genus Homo diverged from the australopithecine line 2.5 million years ago Slide 57 Slide 58 The Genus Homo Homo habilis appeared 2.5 million years ago Bodies and brains were larger than australopithicenes Retained apelike long arms and short legs Homo ergaster appeared 2 million years ago Limb proportions were more like those of modern humans Slide 59 The Genus Homo Homo ergaster is believed by many to be the common ancestor of: H. erectus (first hominid species to leave Africa approximately 1.8 million years ago) H. heidelbergensis Some migrated to Europe and gave rise to H. neanderthalensis Those remaining in Africa gave rise to H. sapiens (modern man) Slide 60 Advances in Tool Technology Hominid evolution is closely tied to the development of tools Homo habilis produced fairly crude chopping tools that were unchipped on one end to hold in the hand Slide 61 Slide 62 Advances in Tool Technology Homo ergaster produced finer tools that were typically sharp all the way around the stone Some of these may have been tied to spears Slide 63 Advances in Tool Technology Homo neanderthalensis produced exceptionally fine tools with extremely sharp edges made by flaking off tiny bits of stone Slide 64 The Neanderthals Neanderthals lived in Europe from 150,000 to 30,000 years ago They were heavily muscled, had brains slightly larger than modern humans, walked fully erect, and constructed finely crafted stone tools Neanderthals were once believed to be a variety of H. sapiens; however, molecular evidence indicates that Neanderthals are a separate species Slide 65 Modern Humans Homo sapiens appeared in Africa about 160,000 years ago European and Middle Eastern H. sapiens appeared about 90,000 years ago and were known as Cro-Magnons Slide 66 Cro-Magnons Cro-Magnons had domed heads, smooth brows, and prominent chins 30,000-year-old Cro-Magnon artifacts include: Bone flutes Ivory sculptures Evidence of elaborate burial ceremonies Unlike their predecessors, Cro-Magnons created remarkable cave paintings that made use of sophisticated artistic techniques Slide 67 Slide 68 Slide 69 Cro-Magnons and Neanderthals Cro-Magnons coexisted with Neanderthals in Europe and the Middle East for as many as 50,000 years It is not known why the Neanderthals became extinct Two hypotheses have been proposed for the evolution of Homo sapiens African replacement hypothesis Multiregional origin hypothesis Slide 70 African Replacement Hypothesis Members of the genus Homo made repeated long-distance migrations out of Africa beginning 1.8 million years ago H. sapiens emerged from Africa about 150,000 years ago and spread across the Near East, Europe, and Asia The dispersing H. sapiens populations replaced all other hominids Slide 71 Slide 72 Multiregional Origin Hypothesis H. erectus emerged from Africa 1.8 million years ago and spread across the Near East, Europe, and Asia Continued migrations and interbreeding occurred among widespread H. erectus populations Regional populations of H. erectus evolved into H. sapiens Slide 73 Slide 74 Large Brains Highly developed brains may have evolved in response to increasingly complex social interactions, such as the cooperative hunting of large game If the distribution of this group-hunted meat was best accomplished by individuals with large brains, then natural selection may have favored such individuals Characteristics made possible by a large brain Language Abstract thought Advanced culture Slide 75 The Cultural Evolution of Humans The evolutionary success of humans is the result of cultural evolution and a series of technological revolutions The development of tools The agricultural revolution The industrial revolution We may not be suited for our role as stewards of lifes continuity on Earth, but here we are. Stephen Jay Gould </p>