EVOLUTION

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EVOLUTION
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H.E.KRON-WHRHS-SCI DEPT
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EVOLUTION
-CHANGE IN THE GENE POOL OF A POPULATION OVER TIME
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SUGGESTS THAT EXISTING SPECIES ARE DERIVED FROM
PREVIOUS ONES BY DESCENT-ORGANISMS NOW ON EARTH
SHARE A COMMON ANCESTRY
EVOLUTION
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IS A UNIFYING THEME IN BIOLOGY PROVIDES A
FRAMEWORK FOR THE ORGANIZATION OF DIVERSE SPECIES
INTO A LINKED PATTERN. A SLOW PROCESS! (AS A RULE
IT OCCURRENCE CANNOT BE DEMONSTRATED DIRECTLY.)
EVOLUTION
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LAMARCK-INHERITANCE OF ACQUIRED
CHARACTERISTICS-ORGANISMS ADAPT TO THEIR
ENVIRONMENT AND PASS THESE CHANGES TO THEIR
OFFSPRING
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USE/DISUSE SALAMANDER-ON LAND, LEGS COULDNT
TRAMPLE THRU TALL GRASS, BEGAN USING THEIR
BELLIES LEG MUSCLES WASTED AWAY FROM
DISUSE LEGLESS SALAMANDERS EVOLVED WHATS WRONG
WITH THIS IDEA?
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DARWINS THEORY OF NATURAL SELECTION FROM HIS
BOOK - ORIGIN OF SPECIES. NEW SPECIES CAME ABOUT
BY NATURAL SELECTION OVERPRODUCTION STRUGGLE
FOR EXISTENCE VARIATION SURVIVAL OF FITTEST
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4 COMPONENTS VARIATION COMPETITION FITNESS ADAPTI
ON
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VARIATION
INDIVIDUAL MEMBERS OF A POP. WITHIN A SPECIES
HAVE HERITABLE DIFFERENCES THESE TRAITS PASSED ON
TO NEW GENERATIONS THESE VARIATIONS ARE RANDOM
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COMPETITION
RESOURCES ARE FIXED EXP-FOOD SHELTER POP.
GROWS TO LIMIT REPRODUCTION EXCEEDS
SURVIVAL INDIVIDUALS MUST COMPETE
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FITNESS
SOME INDIVIDUALS HAVE TRAITS THAT MAKE THEM
BETTER AT SURVIVAL THE FITTEST SURVIVE TO PRODUCE
CARE FOR THEIR OFFSPRING FITNESS IS LINKED TO
THE ENVIRONMENT
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ADAPTION
POP. WITH BEST TRAITS OVER-POPULATE REPLACE
LESS FIT RESULTS IN A NEW POP WITH THE BEST
TRAITS ADAPTION IS THE END RESULT OF N.
SELECTION EXP- COAT COLOR, RUNNING SPEEDS, BODY
COVERINGS. CONCERNS PHENOTYPE OCCURS WHEN GENES
ARE INHERITED
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MICROEVOLUTION VS MACROEVOLUTION
DIVERSITY VS COMPLEXITY
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MICROEVOLUTION ANIMALS PLANTS ADAPT TO
CHANGING ENVIRONMENTS INVOLVES SMALL CHANGES DOES
NOT CREATE NEW SPECIES CREATES DIVERSITY NOT
COMPLEXITY
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EXP MICROEV-SUPPOSE A WHITE BIRD IS BORN AMONG A
POP OF BROWNS. NS FAVORS WHITE IN WINTER BROWN
IN SUMMER. Why? An inherited variation increases
an organisms chance of survival in a particular
environment. THE WHITE BIRD IS NO MORE COMPLEX
THAN THE BROWN!
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BEFORE INDUSTRIAL REVOLUTION THERE WERE PEPPERED
MOTHS. AFTER, OF BLACK MOTHS INCREASED
DRAMATICALLY. WHY? Environment changes moths
adapted-black is no more complex than peppered!
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MACROEVOLUTION evol. that creates a new
species. CHANGES ARE SMALL LARGE Difference
between a wolf dogsmall Difference between a
starfish alligatorlarge
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EXP THAT CREATES COMPLEXITY
Descendants of a lizard evolved into birds with
wings feathers. Birds are more complex than
reptiles.
EXP THAT CREATES DIVERSITY
Descendants of the wolf evolved into dogs
Huskies, Labs etc. A Lab is no more complex than
a wolf.
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NATURAL SELECTION DOES NOT GUIDE EVOLUTIONARY
TRANSITIONS WHICH RESULT IN GREATER
COMPLEXITY-THEY DEPEND ON CHANCE SINCE
OBSERVABLE PROCESSES ONLY CREATE DIVERSITY THEY
SHOULD NOT BE EXTENDED TO EXPLAIN THE ORIGIN OF
COMPLEXITY"
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Modified Sci Method is based more on speculation
than science-c/o-inability of science to test
Macroevolution
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THE EVOLUTION OF COMPLEXITY REQUIRES NEW
GENES GENES ARE CHEMICALS GENES DETERMINE
TRAITS OF PLANTS ANIMALS NEW GENES ARE
REQUIRED FOR THE EVOLUTION OF NEW ORGANS
STRUCTURES
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NEO-DARWINISM SYNTHETIC THEORY
MODERN DISCOVERIES HAVE BEEN INCORPORATED INTO
DARWINS NATURAL SELECTION
THE CELL IS THE SMALLEST UNIT OF LIFE-ALL LIFE IS
COMPOSED OF CELLS
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LIFE BEGINS WITH THE INFORMATION FOUND IN DNA TO
MAKE PROTEINS
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PROTEINS THAT GENES ENCODE ULTIMATELY DETERMINE
THE TRAITS OF AN ORGANISM
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REPRODUCTION IN HIGHER LIFE REQUIRES
MEIOSIS-OFFSPRING INHERIT GENES FROM BOTH PARENTS
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While NS selects existing variations already in a
pop. It does not create new varieties. The
ultimate source of new variations would
be Recombinations of existing
genes Mutations-altered genes/chr Both of these
produce genetic combinations found in earlier
generations
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Recombination/crossing-over homologous chrs
break reattach onto different chrs. The next
generation inherits chrs with new sequences.
Sperm ova can add even greater diversity to a
pops gene pool!
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HOW DO NEW SPECIES EVOLVE
Today scientists realize that variations arise
c/o random changes-Mutations in existing genes.
Point mutation str. Modified irreg.

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MUTATION FACTS
Freq. in human sex cells1/100,000 Humans may
have as many as 100,00 genes Most sex cells
contain mutations are common occurrences in
healthy people Causes radiation, chemicals,
viruses etc.
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For mutation to be subject to NS-it must be
expressed in the individuals phenotype.
Selection favors mutations that result in
adaptive phenotypes and eliminates non- adaptive
ones. Even recessive alleles can show up in
future generations
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ENVIRONMENT SELECTS INDIVIDUALS WITH BEST SUITED
GENOTYPES TO SURVIVE TO ADULTHOOD TO
REPRODUCE. FOR NS TO CAUSE EVOLUTION, IT MUST
SELECT FOR OR AGAINST ONE OF THE FOLLOWING 5
COMBINATIONS
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5 GENOTYPE COMBINATIONS
EITHER AA OR aa (BUT NOT BOTH) BOTH AA OR
aa EITHER AA Aa OR aa Aa HETEROZYGOTE
Aa ALL ALLELES AA, Aa aa
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SELECTION AGAINST ONE OF THE HOMOZYGOTES
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IF aa IS COMPLETELY SELECTED AGAINST WHILE AA
Aa ARE SELECTED FOR- THE FREQUENCY OF aa
CHILDREN WILL DROP DRAMATICALLY. THERE WILL BE A
PROGRESSIVE DECREASE IN a!
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EXAMPLES AGAINST aa ALBINISM-homozygous
recessive individuals are at a slight selective
disadvantage. Can live to adulthood
reproduce. DIABETES-inherited recessive, the
selection is more severe. Prior to this century
those who inherited usually died in childhood.
Since insulin in 1921 it is no longer a killer of
children
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SELECTION AGAINST BOTH HOMOZYGOTES only Aa would
be able to mate!
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NATURE SELECTING AGAINST BOTH HOMOZYGOTES
Malaria found in Africa c/o plasmodia-parasites
that feed on RBC. People who produce norm RBC are
good hosts easily get the disease death
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In African malarial zones there is an inherited
condition of the sickle-cell trait. aa have a
resistance to malaria c/o deflated RBCs are poor
hosts. However these kids die in childhood from
sickle cell anemia.
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People who are Aa for sickle-cell trait have good
resistance to malaria c/o sickle shaped cells and
rarely develop the life threatening anemia. Those
who are AA produce normal RBCs which make
excellent hosts for malaria. So in malarial
environments - nature selects for Aa sicklers. It
selects against aa sicklers people who
produce normal RBCs.
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EVOLUTION IS THE PROCESS BY WHICH GENE POOLS OF A
SPECIES WITH TIME. ALL OF THE SPECIES MAKE UP
THEIR GENE POOL. EVOLUTION CHANGES GENE POOLS AND
CREATES NEW ONES. THEREFORE NS ONLY PRESERVES
GENES THAT OFFER A SELECTIVE ADVANTAGE
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NS only preserves genes that offer a selective
advantage-sometimes called competitive
advantage. These genes are responsible for
beneficial variations.
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EVOLUTION creates diversity by altering the gene
pool. Mutations creates alleles. Alleles are not
new genes, but alternate forms of the same gene.
Exp Hb-a protein for transporting O2. If
mutations change the DNA encoding process, these
changes may alter aa sequence. If the altered
genes still encode for Hb-then they are called
alleles.
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NATURAL SELECTION PRESERVES THE BEST
ALLELES OPTIMIZES EXISTING GENES BY SELECTING
BEST ALLELES MicroEVOL. CONCERNS ORGANISMS
ADAPTING TO CHANGING ENVIRONMENTS NS PRESERVES
ALLELES MORE FIT.
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ENVIRONMENTAL SELECTION
NO EXP LINGULA
Lamp shells found in rock strata 500 mya. Over
all this time still looks the same today!
Gryphaea-coiled shell similar to oyster 180mya
Sea bed changed from rocky to mud. Flat shells
only could survive in rocky areas. Curved shells
could lift upper valve clear of sea bottom
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ADAPTIVE LANDSCAPES-VISUALIZE FITNESS OF ALLELES
Fitness series of valleys and hills Alleles on
hill more fit NS preserves ones on the hill NS
optimizes existing genes by sel. most favorable
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ADAPTIVE LANDSCAPE-APPLIES TO STR ORGANS
Consider a reptile evolving into a bird. Front
legs are preserved by NS. Thus NS fights this
transition. If the transition takes place despite
NS-then only chance can guide it. Mutations away
from optimized legs lower the fitness of a
reptile. NS is not driving such a process.
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GENETIC DRIFT(CHANCE)-DETERMINES WHICH GENES
SURVIVE. ALLELES FREQUENCY OF A GENE POOL DUE
TO CHANCE OR RANDOM EVENTS. CAUSES GENE POOLS OF
2 ISOLATED POPS TO BECOME DISSIMILAR AS SOME
ALLELES ARE LOST OTHERS FIXED.
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The net effect of Genetic Drift on a small pops
gene pool can be rapid. Note the red trait
increases dramatically from generation to
generation
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FOUNDER EFFECT-case of gen. drift in which rare
alleles occur in higher frequency in a pop
isolated from general pop. Exp Darwins finches
When a pop is started by one or a few who
randomly separate from a larger pop-chance may
dictate that allele freq. in new pop. may be
different from original pop.
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Island species vary from mainland species
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BOTTLENECK EFFECT-genetic drift in which a severe
reduction in pop. Size results from natural
disasters, predation or habitat reduction.
Results in severe reduction of the total genetic
diversity of the original gene pool. Exp Cheetah
pop. Was probably reduced in the great Ice Age
10,000 ya. Separation causes infertility c/o
intense inbreedingvery little gen. Variation.
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WHEN ARE TWO POPS NEW SPECIES? - WHEN POPS NO
LONGER INTERBREED THEY ARE THOUGHT TO BE SEPARATE
SPECIES. GENETIC DIVERGENCE RESULTS WHEN
ADAPTION, DRIFT AND MUTATION ACT ON POPULATIONS.
Barriers to gene flow isolate pops lead to
formation of a new species.
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ADAPTIVE RADIATION-the diversification of a
species into two or more species as groups adapt
to different environments
Over time, the pops genetically diverge enough
so that they can no longer reproduce with each
other
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Models of speciation relate to geographic
subdivisions Allopatric-barrier Parapatric-adj.
Pops Sympatric-coexist Founder Effect-small
isolated pop on edge
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VARIATION SPECIATION
VARIATION CAN BE MEASURED IN DIFF WAYS-HUMANS CAN
BE TALL/SHORT, SKINNY/FAT ETC. (VARIATION IS A
DISTRIBUTION OF AVG EXTREMES)
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NATURAL SELECTION IS A PROCESS OF SURVIVAL AND
REDRODUCTION THAT LEADS TO IN ALLELE FREQ.
OVER TIME AS THOSE INDIVIDUALS MOST FIT SURVIVE
AND LEAVE MORE OFFSPRING
THREE PATTERNS
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STABILIZING SELECTION-favors the intermediate
phenotype. Extremes in variation are selected
against. Infants weighing less that 5 lbs have
higher rates of infant mortality.
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DIRECTIONAL SELECTION-favors one or the other of
the extremes. Insecticide resistance with DDT
after yrs of use lost its effectiveness on
insects. Resistence to DDT is a gen. Trait only
those resistant survived reproduced.
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DISRUPTIVE SELECTION-favors individuals at both
extremes-sel. against middle of the curve causing
2 or more distinct phenotypes. African
butterflies have 2 distinct phenotypes both
resemble brightly colored but distasteful
butterflies of other species. Each one gains
protection from predation although they are quite
edible.
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DISRUPTIVE-favors both extremes
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HARDY-WEINBERG THEOREM IDEA DEVELOPED TO
DETERMINE IF A POP. WAS EVOLVING. AUTHORS SET UP
A SERIES OF PARAMETERS WHICH DO NOT EXIST IN
NATURE TO BE FOLLOWED WHEN DETERMINING THE ALLELE
FREQUENCIES OF ANY POP.
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EVOLUTION WILL NOT OCCUR IF NO NATURAL
SELECTION NO MUTATIONS POP. MUST BE A LARGE
SIZE RANDOM MATINGS POP. MUST BE ISOLATED-NO
GENE FLOW
SINCE IT IS HIGHLY UNLIKELY THAT ANY OF THESE
CONDITIONS WILL OCCUR IN THE REAL WORLD,
EVOLUTION IS THE INEVITABLE RESULT
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FOSSILS
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FOSSILS
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FOSSIL EVIDENCE
Remains of living things that existed long ago
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PETRIFICATION IMPRINTS CASTS FREEZING TAR
PITS AMBER
FOSSILS
BUT THERE ARE MISSING LINKS BETWEEN EVERY MAJOR
GROUP OF PLANTS AND ANIMALS
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STUDY OF FOSSIL RECORDS HELPS BUILD A HISTORICAL
SEQUENCE OF BIO EVOLUTION OF COMPLEX ORGANISMS
FROM SIMPLE ONES.
Sequence of snail shells oldest on left
youngest on the right dated from 10 mya to 3 mya
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Horse evolved from 5-toed browser to 1-toed grazer
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FOSSILS
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DARWIN BELIEVED THAT OVER TIME THAT SPECIES
EVOLVED C/O GRADUAL IN FREQ. OF TRAITS.
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THEORY OF PUNCT. EQUILIBRIUM HAS BEEN DEVELOPED
TO EXPLAIN RATES OF THAT OCCUR AT AN UNEVEN
TEMPO.
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PE IN NATURE OCCURS C/O ABRUPT IN THE WORLDS
CLIMATE ENVIRONMENTS. SPECIATION OCCURS RAPIDLY
FOLLOWED BY LITTLE OR NO
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FACTS
Darwin recognized that the fossil record is not
continuous Most transitional forms have yet to be
found Missing links undermine the entire theory
of evolution With PE idea, the fossil record can
no longer be used to disprove evolution
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BIOGEOGRAPHICAL
DISTRIBUTION OF ORGANISMS
Animals plants are most closely related to
those in nearby regions
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BIOGEOGRAPHICAL
TWO HYPOTHESES RELATED FORMS EVOLVE IN ONE PLACE
SPREAD OUT TO OTHER REGIONS SAME TYPE OF
ADAPTION IN GEOGRAPHICAL REGIONS SEPARATES
ORGANISMS
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GRADUAL ISOLATION BY NEW LAND FORMS, WATER,
HIGHWAYS, VOLCANO, EQ, RIVERS.
Ice Age-one body of water one species of fish.
Dries up in diff. areas. Fish pop isolated. Fish
diverged could no longer interbreed even if
brought together.
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REPROD. ISOLATION
Inability of formerly inter- breeding to
reproduce offspring. Early and late frog breeding
times have been selected against c/o predators
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CONVERGENT EVOLUTION
Unrelated species become similar in appearance as
they adapt to same kind of environment.
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MANY DIVERSE ORGANISMS SHOW ANATOMICAL
SIMILARITIES
COMP ANATOMY
Bat wing
Bird wing
Pterodactly wing
Human arm
HOMOLOGY-SIMILAR STRS IN DIFFERENT SPECIES OFTEN
DESPITE DIFF FUNCTIONS
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COMP ANATOMY
FORM FOLLOWS FUNCTION
IF 2 SPECIESHAD A COMMON ANCESTOR THEYSHOULD HAVE
MAINTAINED BUT MODIFIED THE SAME COMPONENT
PARTS, BONES, MUSCLES ETC. HOMOLOGOUS STRS
PHYSIOLOGICAL STRS THAT HAS BEEN ADAPTED FOR A
NEW FUNCTION.
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COMP ANATOMY
VESTIGAL STRS - REMAINS OF STRS THAT WERE
FUNCTIONAL IN SOME ANCESTOR. ARE OFTEN HOMOLOGOUS
TO ORGANS THAT ARE USEFUL IN OTHER SPECIES.
Human tail bone is homologous to functional tails
of other primates
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COMP ANATOMY
ANALOGY-SIMILAR FUNCTION BUT DIFFERENT
STRUCTURES EXP BIRD WINGS INSECT WINGSFLIGHT
BUT DIFFERENT STRS VARIATIONS.
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NEARLY ALL ORGANISMS USE THE SAME BIOCHEMICAL
MOLECULES-DNA, ATP ENZYMES
BIOCHEMICAL
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COMPARISON OF BASES BETWEEN CHIMP AND HUMAN
99.125 SIMILARITY
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EMBRYOLOGY
EARLY STAGES OF DEVELOPMENT OF EMBRYOS SHOW
PECULIAR SIMILARITY
SUGGESTS COMMON ORIGIN
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PURPLE-SULFUR BACTERIA
PRECAMBRIAN TIME
STROMATOLITES-BACT COMMUNITIES
CS
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PALEOZOIC ERA
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CAMBRIAN EXPLOSION SHOWS NUMEROUS FAMILIES OF
PALEOZOIC FAUNA
BRACHIOPODS
TRILOBITE
SMALL MARINE INVERTEBRATES PLUS CORALS
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ECHINODERMATA-SPINY-SKINNED RADIAL SYMMETRY
AGRIOCRINUS-FOSSIL SOFT BODIED UNMINERALIZED
PARTS
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OUR OWN PHYLUM WAS REPRESENTED BY A SMALL
SLIVER-LIKE THING THE - PIKAIA - FOUNDER OF
PHYLUM CHORDATA?
CAMBRIAN
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CAMBRIAN
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Plants evolved from algae c/o chlorophyl starch
storage- moss first land plants but still need H2O
SILURIAN
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First vascular land plant- cooksonia-no leaves,
flowers or seeds but probably root hairs and
sporangia(420mya)
Silurian
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DEVONIAN PER
FIRST LAND ANIMALS-Myriapods, centepedes,
millipedes
Worms with appendages
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TETRAPOD EVOL. FROM FISH OUT OF H2O. FISH HAD
SERIES OF BONES ARRANGED LIKE ARMS/LEGS.
DEVONIAN PER
TETRAPOD ANTHRACOSAUR
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TETRAPOD AMPHIBIAN-TRANSITION FORM BETWEEN FISHES
AMPH. WITH NOTOCHORD SPINE RIBCAGE
ICHTHOSTEGA-AMPH. BELIEVED TO BE FIRST LAND VERT.
DERIVED FROM LOBE FINNED FISH
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DEVONIAN DROUGHTS MAY HAVE BEEN CAUSE FOR NS TO
FAVOR THOSE FISHES WHO VENTURED OUT TO PARCHED
EARTH
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COELACANTH-LOBE FINNED RHIPIDISTIANS
LUNGFISH-EXTINCT
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AMPHIBIANS VERT. ADULTS USE LUNGS LARVAE-LONG
TAILS USED GILLS COLD-BLOODED EGGS LAID IN
H2O HAVE EXISTED 350MYA OLDEST GROUP OF
TERRESTRIAL VERTEBRATES
ANDRIAS
PTERPLAX
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CARBONIFEROUS
FERN-ALLOPTERIS (307MYA)
FERNS GYMNOSPERMS REPTILES
PERMIAN
REPTILE-DIMENTRODON
REPTILE-HYLONOMUS
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FERN-LYGINOPTERIS 307MYA
FERN-GLOSSPTERIS
CLUB MOSS-LEPIDODENDRON-LEAF SCARS ON TRUNK-100FT
ACROSS 3FT DIA.
FERN-CALAMITES- SPORE-BEARING
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CARBONIFEROUS LAND PLANTS AND INSECTS
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POST PERMIAN EXTINCTION-GYMNOSPERMS BECAME
ABUNDANT. HAVE SEEDS FROM SEEDLESS ANCESTORS -
HELPED TO DISPERSE ENCASED SPERM
POST PERMIAN
PONDEROSA 2455 YRA
ARISTATA CONES 2455 YRA
LEBACHIA-OLDEST RELATIVE OF CONIFERS
BRISTLECONE GHOST 4776 YRA
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EUPARKERIA-BELIEVED TO BE RELATIVES OF ARCHOSAURS
THE CROCODILES, DINOSAURS, AND BIRDS. SEEM TO BE
BIPEDAL FOR SHORT DISTANCES
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TRIASSIC-245-208mya-middle animals-reptile like
mammals dinosaurs JURASSIC-208-146mya-more
dinosaurs and first mammals appear CRETACEOUS-146-
65mya-first flowering plants. Extinction of
dinosaurs modern birds appearlife as it now
exists on earth.
MESOZOIC ERA
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MESOZOIC ERA
TRIASSIC JURASSIC CRETACEOUS
Pangaea breaks apart almost like today
Hot dry warm/moist warm, high
sea level
Seasonality no polar ice later
sea levels down strong
flooded plains greater extremes
Small dinos archaeopteryx dinos
flourish ferns, cycads flying pterosaur
angiosperms
Gymnosperms large dinos ants
butterflies
Major extinction at end of this era
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DINOSAURS EVOLVED FROM ARCHOSAUR REPTILES-THEIR
CLOSEST RELATIVES ARE CROCODILES
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Dinos evolved upright stance warm blooded which
allowed for continuous locomotion. Cladistically
birds are dinosaurs.
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Transitional fossil-mix of reptilian avian
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CRETACEOUS TO TERTIARY
Angiosperms evolved from gymnosperms. Closest
relatives are the Gnetophytesoutcrops of the
flowering plants.
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ANGIOSPERMS ARE THE DOMINATE FLORA OF THE
WORLD(3/4 OF ALL LIVING PLANTS ARE
ANGIOSPERMS)DEVELOPED FRUITS FLOWERS FOR POLLEN
AND SEED DISPERSAL
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EXTINCTION-DECREASE IN BIOLOGICAL
DIVERSITY. 99.9 OF ALL SPECIES THAT EVER EXISTED
ARE NOW EXTINCT! WHY?
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ENVIRONMENTAL CHANGE
LIVING competition, new parasites, new
predators, new prey defenses. NON-LIVING
climate, soil, pH, salinity.
Extinction occurs after a species has been
reduced to a very limited distribution or has
become specialized in its food, habitat or
behavior patterns
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EXAMPLES Everglades kite feeds on a certain
snail whos pop was reduced by swamp
draining. Ivory-billed woodpecker was eliminated
by destruction of southern forests Sea cows swim
slowly along shorelines and were easy targets for
whalers in Pacific NW-went extinct.
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Will our species become extinct?
Nuclear winter-cooling effects of a large number
of explosions results in dust or particles in the
air blocking sunlight. Global nuclear war could
produce temperatures of less than -40 C in 80
days-most crops and some humans would not
survive. Comets and asteroids-impacts would throw
up large clouds of particulate.
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Impact on other species due to Habitat
destruction by man Introduction of competing
predatory species parasites by man
Overexploited resources by humans.
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ACKNOWLEDGEMENTS
www.axel-and-alice.com/ghbc www.talkorigins.org ww
w.xs4all.nl/steurh //fp.bio.utk.edu/darwin //team
work.icdavis.edu //depts.washington.edu/vert www.g
pc.peachnet.edu/pgore //geology.wr.usgs.gov www.u
cmp.berkeley.edu/vertebrates www.life.umd.edu/clas
sroom/bsci124 //daphne.palomar.edu/wayne/ww060/ ww
w.zoomdinosaurs.com www.kean.edu/biology
//bioweb.cs.earlham.edu/9-12/evolution
www.fieldmuseum.org/exhibits
www.time-travel.com/cenozoic
www.infoplease.com //bioserve.latrobe.edu.au/
vcebiol //ald.zen.uni-breman.de
//library.thinkquest.org/19926
//biocrs.biomed.brown.edu.Books
//darwinsmistake.com www.sprl.umich.edu/glc
//fig.cox.miami.edu/faculty/Tom/bil160
www.sc2000.net/czarembra
www.truman.edu/academics/ss