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Evolution

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hasanahatesscience's version from 2017-04-19 23:59

Section 1

Question Answer
there was a church doctrine about living things (ideas in 17-18th century)1)a) all creatures have been created independantly of one another by God b)"chain of being" humans occupy the most elevated rank beneath God 2)earth is 6000 years old
james huttonfound volcanic rock which pentrated sedimentary rock. Salisbury Crags - twisting distortion of sedimentary rock. Siccar Pt - sediment layers showing uplifting. Ideas: 1)CYCLE OF DEPOSITION (EROSION UPLIFTN) TO FORM SEDIMENTARY ROCK 2)GEOLOGIC FORCES ARE SLOW N UNIFORM. UNIFORITARIANISM (earth changes slowly and steadly) this proves earth is not 6000 yrs old
charles lyell - god father of geologyexplained earthquakes+volcano formation. published book w huttons idea. stated present is key to the past meaning fossils and rocks tell us about environments. Charles changed uniforiitarianism w exceptions of earthquakes n volcanos
george cuiver - species become extinctfrench paleontologist. compared skeleton of mastodon from ohio to elephant, determined they were different. His idea: species go extinct n extinction can go very quickly
jean baptise lamarkIdea: 1)species evolve. 2)way evolution occurs is through personal effort. Ex:giraffes long necks came by stretching. babies born w longer necks.
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darwins trip

Question Answer
charles darwin descripson of succesful dr. flunked out of med school. liked nature made insect collection. studied taxidermy + clams life cycle. after uni, secured unpaid position as a naturalist on a ship called HMS Beagle. lasted 5 yrs collected 1000s of specimens
islands in atlantic. found clam fossils at mtn top. IDEAnothing changes
found giant sloth skelton (extinct) CHALLENGES earth is older than 6000 yrs and species change
found flightless birds this implied change with distinct ranges
he found a raised beach. formley underwater found urchin fossils CHALLENGES species do change and change occurs regularly
found earthquakes lifted the rocks 10 ft up challenged the idea that nothing changes. also found: fossilized trees from sea level near top of mtn. challenges: earth changes
archipelago (group of islands) each island is isolated. found animals unique (endemic) to galapagosex: giant tortoise was found and considered unique. ex: 13 diff Finch species which were filling niches (eating insects n fruits) normally filled by other species. NICHE=job of organism in environment
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  weird mursupials occupying all niches :ex: england: deer austrailia: kangaroo

Section 3

Question Answer
darwins findings. environment controls phenotype of organism living in itex: grassland -> animals that can run ex: southern hemisphere > flightless birds (emu ostrich rhea)
ancestral beings lead to current life formsglyptodant -> armadillo. ancient horse > horse zebra donkey. auroch - black cow hostein
thomas malthusdarwins influence by thomas malthus who said "humans compete w each other"
darwins explantation of how species changedall species living on earth today are descended from ancestrial species (evolving overtime) 2)species change and evolve due to natural selection
natural selectionstruggle for existence (excessive offspring limited resources and competition for those resources)
how natural selection worksvariation selection and repeated for many generations
within a species there is variationvariation exists n is inherited. certain varients are fitter.
factors affectin natural selection: biotic predators food supply bacteria and viruses
factors affectin natural selection: abiotic temp soil type rainfall
factors affecting natural selection: fitnesshow many babies you have that survive to adult hood and that produce babies
IMPORTANT TO NOTE: natural selection does nothave a plan or direction
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evidence for natural selection

Question Answer
evidence for natural selectionfor 30 summers, rosemary and peter grant captured tagged weighed and maeasured the beak size of every finch on a small island of Galapagos
what was foundpopulations varied in beak size. small beak=ate small seeds. big beak =big seeds. small seeds are plentiful in wet yrs. big seeds come in dry yrs
other examples of natural selection antibiotic resistence in bacteriainstead of using antibiotics, use good hygiene to kill bacteria
other examples of natural selection insectsare now resistant to pesticides (harms humans too) u can a)change their habitat b)spray them with soap n water
evidence of evolution: fossil recordconsist of hard parts of an organism shells bones claws teeth. soft parts rarely form fossils, so will find impressions (foot prints) FOSSIL RECORD SHOWS 1)species evolve 2)species go extinct 3)intermediate forms
missing linksintermidiate forms not yet found. reptiles > ? > birds. Aerchaeopteryx > teeth, wings/feathers, not a mammal
adaptive radiationprocess which results from one ancestral species evolving into many related species each with diff niche. (darwins finches)
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Section 5

Question Answer
evidence in support of evolution: fossil recordexplained before, disregard this
geographic distributionmain idea; related species which have common ancestor will be located near each other. ex:california salamanders, butterflies in central america
comparative anatomyorganisms with a common ancestor will have similar or homologous body parts ex:forelimbs or vertebrates have same bones but diff sizes (hind limbs of vertebrates)
comparative embryologyembryos of closely related organisms will have simular development stages (humans at 8 wks have gills and tails)
molecular biologyclosely related organisms will have the same dna sequence for important proteins like hemoglobin
vestigial structuresbody parts that do not have a use in a current organism but did in the ancestor (human appendix, wisdom teeth, whole pelvis)
analagous structurebody parts like Wings in insects vs wings in vertebrates that do the same job but developed independantly (no common ancestor)
molecular clockmethod to predict when 2 species had common ancestor. compares the dna sequence or 2 imporant n common proteins. # of nucleotide changes indicates how long ago species diverged
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Section 6

Question Answer
how variation in pop comes about, known asmicroevolution
gene poolall the alleles present in a population, new alleles form thru mutations of dna
changes in dna occur due otexposure to radiation, virus infection of cells, and chemicals like caffiene/tobacco
most mutations r deadly some mutations confer survival advantagesickle cell gene protects people who are heterozygous from malaria. protein deforms the blood cell, parasite cannot invade
mechanisms of microevolution (how does gene pool change)1.immigration and emmigration 2.Natural selection-3 types
disruptive selectionextreme phenotypes are more successful
directional selectionone pheno is more successful
stabalizing selectionhuman height human birthweight, intermidiate pheno type is successful
sexual selectionorganisms choose their mates, choose by best looking/health (peacock w big tails)
artificial selectionhumans control which organisms have sex. Belgian blue cows - muscle size
genetic drift a)bottleneck effect- accidental loss of alleles from a population thru overhunting/natural disaster. ex: elephant seals r hunted.
genetic drift b)founder effectwhen small population settle in an area. if they dont bred their descendants will have high liklihood of homozygous recessive disorders
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Section 7

Question Answer
speciation or macroevolution:how new species comes about
speciesorganism that mates in the wild and produces fertile offspring
mechanisms of speciations: 1.reproductive isolating mechanism.see mechanisms (isolations)
2.sympatric speciation - some plants and lower animals can double and triple chromosome #. called POLYPLOID. different species can interbred if their PLODY is the same.
3.allopatric speciation/geographic isolationbc environmental conditions differ and sometimes things far away from each other cant interbred. ex:california salamander vs Owls
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Section 8

Question Answer
pre zygoticinterfere w/ mating fertilization, prevents mating and fertilization
post zygoticinterferes w babies survival, hybird not viable, hybrid is sterile, hybrid breakdown
pre zyg: behavioural isolationany special signal related species have to prevent interbreeding (special bird songs, diff courtship rituals in elk)
pre zyg: habitat isolation2 related species that live close to each other have slightly diff habitats (wet vs dry) dont cross paths and dont interbreed ex:common vs garder snake
pre zyg: temporal isolationwhen 2 related species are ready to mate at diff times thus do not interbreed ex: wood vs leopard frog
pre zyg: mechanical isolationgenetalia of related species do not fit together or some plants accept only one pollinator
pre zyg: gamete isolationfemale reproductive tract is hostile to wrong sperm
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Section 9

Question Answer
convergent evolutionanimals which are not closely related species but have same body shape living in simular habitat. ( sharks vs dolphins, ant eating animals) convergent evolution occurs bc organisms will exploit every food/habitat possible
divergent evolutionancestral species/stock evolves into 2 species + continue to evolve. ex: ancestral fish > 13 species of darwins finches. ancestral horse > zebra donkey modern horse. divergent evolution occurs bc organisms will exploit all food n habitats possible.
both convergent and divergent reduce competition and survivorship
rate of speciationhow fast do new species form. there are 2 models
1)gradualismspecies change slowly, proposed by darwin.ex:development of complicated strucutres like eyes or human brain-cumulative selection
2)punctuated equilibriumspecies stay same for long period of time then change quickly. antibiotic resistant bacteria
coevolutionwhen an organism changes in response to change in another organism (predators and prey
mimicry- + wasp vs hoverfly
camoflageplant vs leaf insect (? +)
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Section 10

Question Answer
origin of life on earthearth is 4.6 bill yrs old. first living things were archaea which r thought to have evolved near deep sea vents about 3.5 bill yrs ago
evidence in support of 1st life are stromatolitesthese rocks formed from colonial unicellular bacteria, their relatives still exist in the bahamas b.c austrailia
theorys on how n when life started (oparin/haldene)1.inorganic molecules-H2o, h2, 2.small organic molecules-carbs proteins lipids. 3.larger organic molecules 4.molecules copy themselves 5.molecules wrap themselves in a membrane
step 1 small inorganic -urey miller aparatus simulated ancient atmosphere w electric shocks n u.v and resulted in amino acids. Ancient atmosphere in water that froze -nitrogenous base formed. Murchison Meteor - contrained 90 diff amino acids(nucleotides) 19 used by humans
where life startedas the surface of ancietn earth was inhospitable to life it is predicted life started as bacteria in deep sea vents
proposed steps that started life1.chemotroph-use h2S from deep sea vemts (anerobic bacteria) 2.cyanobacteria - photosynthesizers evolved and released O2. 3.at that time oceans dissolved irion. once o2 was available iron preciptated out evidence baned irion
evolution from prokaryotes to eukaryotesinitially diverse prokaryotes existed. to survive the big ones needed to increase their surface area.
endosymbiosissmall bacteria lived symbiotically (mitochondria and chloroplast) multicellular forms evolved
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Section 11

Question Answer
geological time scaleway to organize earths history into different time periods. shows 5 major extinction.
continental driftcause of climate change proven by fossil location
phylogentic treeshows who is related to whom. sometimes homologous structures are hidden ex: fingerbones in bats r located in wings
cladeone branch of the evolutionary tree
cladogramdiagram shows how species r related
cladisticsmethod to determine whos related to whom
primate phylogenyprimates evolved about 63 mill yrs ago. characterized by grasping hands feet n opposable thumbs. foward facing eyes
primates-prosimigns and anthropodsfrom anthropods evolved new world monkeys and old world monkeys(africa).from old world monkeys came apes and hominoids(no tails, smart swinging arms), from this came hominids4.6 mill yrs ago and then came US!!! HOMOSAPIEN SAPIEN
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