studied medicine atstudied medicine at
Edinburgh UniversityEdinburgh University
(1825-1827) where the(1825-1827) where the...
After Cambridge, Charles was recommendedAfter Cambridge, Charles was recommended
for a surveying trip on thefor a surveyin...
Darwin made manyDarwin made many
observations andobservations and
collected evidencecollected evidence
on his voyage thato...
At the time Darwin madeAt the time Darwin made
his trip, the majority ofhis trip, the majority of
people believed the Eart...
People also believed inPeople also believed in fixity of speciesfixity of species;; in otherin other
words, species never ...
Darwin was influencedDarwin was influenced
by geologist Jamesby geologist James
Hutton’s writings thatHutton’s writings th...
Darwin was alsoDarwin was also
influenced byinfluenced by
geologist Charlesgeologist Charles
Lyell who wroteLyell who wrot...
On the voyage,On the voyage,
Darwin noticedDarwin noticed
that everywhere hethat everywhere he
went, the animalswent, the ...
The GalapagosThe Galapagos
Islands lie 500 milesIslands lie 500 miles
west of Ecuador inwest of Ecuador in
the Pacific Oce...
What it must have been
like to be Darwin…
Darwin noticed onDarwin noticed on
these islands,these islands,
there were sever...
In particular,In particular,
Darwin observedDarwin observed
something oddsomething odd
about theabout the
finches: they al...
Darwin wondered if the birds and otherDarwin wondered if the birds and other
animals had beenanimals had been createdcreat...
Darwin guessed thatDarwin guessed that
some of the birdssome of the birds
from South Americafrom South America
migrated to...
This would explain the numerous species ofThis would explain the numerous species of
birds present.birds present.
This wou...
Darwin called this…Darwin called this…
oror
(change in species over time)(change in species over time)
Darwin concluded:Da...
Malthus was a BritishMalthus was a British
social scientist whosocial scientist who
proposed theories onproposed theories ...
Darwin extended theseDarwin extended these
principles to biology, whichprinciples to biology, which
helped him form his th...
Natural selection was theNatural selection was the
mechanism by whichmechanism by which
Darwin proposed thatDarwin propose...
Five basic components ofFive basic components of
1. All species have genetic variation.1. All species have genetic variation.1. All species have genetic variation.1. All s...
2.2. Organisms produce more offspring thanOrganisms produce more offspring than
can survivecan survive. Many that survive ...
3.3. Since more organisms are produced thanSince more organisms are produced than
can survive, there iscan survive, there ...
The constant struggle for survival is affected by
short-term natural disasters. (drought, fires,
floods, snowstorms, hurri...
4.4. Survival of the fittestSurvival of the fittest Some organismsSome organisms
are more suited to their environment as a...
5.5. Descent with modificationDescent with modification:: Living speciesLiving species
today are descended with modificati...
Natural Selection: Survival of the FittestNatural Selection: Survival of the FittestNatural Selection: Survival of the Fit...
As the environment changes, organisms mustAs the environment changes, organisms must
have variations that allow them to su...
There have been at least 5 MASS extinctionsThere have been at least 5 MASS extinctions
during Earth’s history where a huge...
It is estimated thatIt is estimated that 1/5 or more of the world’s1/5 or more of the world’s
speciesspecies will become e...
• What do you think biodiversity is?
• ANSWER: the variation of life forms in an
ecosystem
• How do you think biodiversity...
If we are in a period of mass extinction . . .If we are in a period of mass extinction . . .
What animals will your grandc...
Davis, Donald E. “Meteor Impact”. (Also public domain from NASA.)
No date. Online image with permission. Dinosaurs and The...
Darwin and natural_selection
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  • Photo from original manuscript of William Buckland
  • Mineral Management Service photo courtesy of GeekPhilospher.com
    http://geekphilosopher.com/bkg/snowAlaskaIce.htm
  • Photo – National Park Service – Dinosaur National Monument
  • For an article on mass extinctions and the % of loss, see
    http://www.space.com/scienceastronomy/planetearth/extinction_sidebar_000907.html
    Photo courtesy of Donald E. Davis, also in public domain from NASA.
  • Photo – Clearcut in Cameroon rainforest. - Earth Crash Earth Spirit - http://www.eces.org/archive/gallery/forestsgfx/forests39.shtml
  • Current mass extinction crisis will wipe out 24% of the world's mammals within 30 years (including tigers, rhinos, Asian elephants, cheetahs and mountain gorillas); 12% of birds and over 5,000 plants are also expected to become extinct by 2032 due to loss of habitat, the introduction of non-native species, and other human impacts. (UNEP – United Nations Environment Program)
    Photos by Martin Harvey from the World Wildlife Fund – www.panda.org
  • Darwin and natural_selection

    1. 1. studied medicine atstudied medicine at Edinburgh UniversityEdinburgh University (1825-1827) where the(1825-1827) where the sight of blood andsight of blood and surgery withoutsurgery without anesthetics repulsed himanesthetics repulsed him studied medicine atstudied medicine at Edinburgh UniversityEdinburgh University (1825-1827) where the(1825-1827) where the sight of blood andsight of blood and surgery withoutsurgery without anesthetics repulsed himanesthetics repulsed him studied to become astudied to become a clergyman at Cambridgeclergyman at Cambridge University (1827-1831)University (1827-1831) studied to become astudied to become a clergyman at Cambridgeclergyman at Cambridge University (1827-1831)University (1827-1831) born in Shrewsbury,born in Shrewsbury, England, in 1809England, in 1809 born in Shrewsbury,born in Shrewsbury, England, in 1809England, in 1809
    2. 2. After Cambridge, Charles was recommendedAfter Cambridge, Charles was recommended for a surveying trip on thefor a surveying trip on the HMS BeagleHMS Beagle.. After Cambridge, Charles was recommendedAfter Cambridge, Charles was recommended for a surveying trip on thefor a surveying trip on the HMS BeagleHMS Beagle.. Darwin sailed around the world on theDarwin sailed around the world on the BeagleBeagle for 5 years, working as a naturalist.for 5 years, working as a naturalist. Darwin sailed around the world on theDarwin sailed around the world on the BeagleBeagle for 5 years, working as a naturalist.for 5 years, working as a naturalist.
    3. 3. Darwin made manyDarwin made many observations andobservations and collected evidencecollected evidence on his voyage thaton his voyage that led to his theoryled to his theory about the way lifeabout the way life changes.changes. Darwin made manyDarwin made many observations andobservations and collected evidencecollected evidence on his voyage thaton his voyage that led to his theoryled to his theory about the way lifeabout the way life changes.changes.
    4. 4. At the time Darwin madeAt the time Darwin made his trip, the majority ofhis trip, the majority of people believed the Earthpeople believed the Earth and all of its forms of lifeand all of its forms of life had been created only ahad been created only a few thousand years infew thousand years in the past.the past. At the time Darwin madeAt the time Darwin made his trip, the majority ofhis trip, the majority of people believed the Earthpeople believed the Earth and all of its forms of lifeand all of its forms of life had been created only ahad been created only a few thousand years infew thousand years in the past.the past.
    5. 5. People also believed inPeople also believed in fixity of speciesfixity of species;; in otherin other words, species never changedwords, species never changed.. People also believed inPeople also believed in fixity of speciesfixity of species;; in otherin other words, species never changedwords, species never changed.. After carefulAfter careful observation andobservation and study of newstudy of new scientificscientific discoveries,discoveries, Darwin began toDarwin began to think otherwise.think otherwise. After carefulAfter careful observation andobservation and study of newstudy of new scientificscientific discoveries,discoveries, Darwin began toDarwin began to think otherwise.think otherwise. People also believed that the Earth had notPeople also believed that the Earth had not changed during those few thousand yearschanged during those few thousand years.. People also believed that the Earth had notPeople also believed that the Earth had not changed during those few thousand yearschanged during those few thousand years.. The first dinosaur to be described scientifically was Megalosaurus by William Buckland in 1824.
    6. 6. Darwin was influencedDarwin was influenced by geologist Jamesby geologist James Hutton’s writings thatHutton’s writings that described geologicdescribed geologic forces he thought hadforces he thought had changed and were stillchanged and were still changing the earth.changing the earth. Darwin was influencedDarwin was influenced by geologist Jamesby geologist James Hutton’s writings thatHutton’s writings that described geologicdescribed geologic forces he thought hadforces he thought had changed and were stillchanged and were still changing the earth.changing the earth. Hutton proposed thatHutton proposed that the Earth had to bethe Earth had to be much more than a fewmuch more than a few thousand years old.thousand years old. Hutton proposed thatHutton proposed that the Earth had to bethe Earth had to be much more than a fewmuch more than a few thousand years old.thousand years old. The Father of GeologyThe Father of GeologyThe Father of GeologyThe Father of Geology
    7. 7. Darwin was alsoDarwin was also influenced byinfluenced by geologist Charlesgeologist Charles Lyell who wroteLyell who wrote Principia GeologicaPrincipia Geologica.. Darwin was alsoDarwin was also influenced byinfluenced by geologist Charlesgeologist Charles Lyell who wroteLyell who wrote Principia GeologicaPrincipia Geologica.. Lyell’s book proposedLyell’s book proposed that tremendousthat tremendous geologic processesgeologic processes had shaped the Earthhad shaped the Earth such as seen insuch as seen in volcanoes active involcanoes active in the present.the present. Lyell’s book proposedLyell’s book proposed that tremendousthat tremendous geologic processesgeologic processes had shaped the Earthhad shaped the Earth such as seen insuch as seen in volcanoes active involcanoes active in the present.the present.
    8. 8. On the voyage,On the voyage, Darwin noticedDarwin noticed that everywhere hethat everywhere he went, the animalswent, the animals and plants differedand plants differed vastly.vastly. On the voyage,On the voyage, Darwin noticedDarwin noticed that everywhere hethat everywhere he went, the animalswent, the animals and plants differedand plants differed vastly.vastly. Patterns in the speciesPatterns in the species suggested that thesuggested that the species had changedspecies had changed over time and had givenover time and had given rise to new and differentrise to new and different species.species. Patterns in the speciesPatterns in the species suggested that thesuggested that the species had changedspecies had changed over time and had givenover time and had given rise to new and differentrise to new and different species.species.
    9. 9. The GalapagosThe Galapagos Islands lie 500 milesIslands lie 500 miles west of Ecuador inwest of Ecuador in the Pacific Ocean,the Pacific Ocean, directly on thedirectly on the equator.equator. The GalapagosThe Galapagos Islands lie 500 milesIslands lie 500 miles west of Ecuador inwest of Ecuador in the Pacific Ocean,the Pacific Ocean, directly on thedirectly on the equator.equator. Many of Darwin’sMany of Darwin’s conclusions wereconclusions were based onbased on observations ofobservations of wildlife in thewildlife in the Galapagos Islands.Galapagos Islands. Many of Darwin’sMany of Darwin’s conclusions wereconclusions were based onbased on observations ofobservations of wildlife in thewildlife in the Galapagos Islands.Galapagos Islands. “Galapagos” means turtle.
    10. 10. What it must have been like to be Darwin… Darwin noticed onDarwin noticed on these islands,these islands, there were severalthere were several types of finches.types of finches. Darwin noticed onDarwin noticed on these islands,these islands, there were severalthere were several types of finches.types of finches.
    11. 11. In particular,In particular, Darwin observedDarwin observed something oddsomething odd about theabout the finches: they allfinches: they all looked like alooked like a bird he had seenbird he had seen on the Southon the South AmericanAmerican continent.continent. In particular,In particular, Darwin observedDarwin observed something oddsomething odd about theabout the finches: they allfinches: they all looked like alooked like a bird he had seenbird he had seen on the Southon the South AmericanAmerican continent.continent.
    12. 12. Darwin wondered if the birds and otherDarwin wondered if the birds and other animals had beenanimals had been createdcreated to match theirto match their environment, why didn’t these birds look likeenvironment, why didn’t these birds look like the birds of the African continent, since thethe birds of the African continent, since the environments of both the Galapagos andenvironments of both the Galapagos and Africa were similar.Africa were similar. Darwin wondered if the birds and otherDarwin wondered if the birds and other animals had beenanimals had been createdcreated to match theirto match their environment, why didn’t these birds look likeenvironment, why didn’t these birds look like the birds of the African continent, since thethe birds of the African continent, since the environments of both the Galapagos andenvironments of both the Galapagos and Africa were similar.Africa were similar.
    13. 13. Darwin guessed thatDarwin guessed that some of the birdssome of the birds from South Americafrom South America migrated to themigrated to the Galapagos.Galapagos. Darwin guessed thatDarwin guessed that some of the birdssome of the birds from South Americafrom South America migrated to themigrated to the Galapagos.Galapagos. Once on the islands,Once on the islands, the birds must havethe birds must have changed over thechanged over the years.years. Once on the islands,Once on the islands, the birds must havethe birds must have changed over thechanged over the years.years.
    14. 14. This would explain the numerous species ofThis would explain the numerous species of birds present.birds present. This would explain the numerous species ofThis would explain the numerous species of birds present.birds present. woodpecker finch cactus finch large ground finch
    15. 15. Darwin called this…Darwin called this… oror (change in species over time)(change in species over time) Darwin concluded:Darwin concluded: Each species has descended, with changes,Each species has descended, with changes, from other species over time.from other species over time. Darwin concluded:Darwin concluded: Each species has descended, with changes,Each species has descended, with changes, from other species over time.from other species over time. Descent With ModificationsDescent With ModificationsDescent With ModificationsDescent With Modifications
    16. 16. Malthus was a BritishMalthus was a British social scientist whosocial scientist who proposed theories onproposed theories on factors controllingfactors controlling population growth:population growth: Malthus was a BritishMalthus was a British social scientist whosocial scientist who proposed theories onproposed theories on factors controllingfactors controlling population growth:population growth: People have more children than arePeople have more children than are able to survive.able to survive. People have more children than arePeople have more children than are able to survive.able to survive. There are built-in population checks:There are built-in population checks: disease, famine, and war.disease, famine, and war. There are built-in population checks:There are built-in population checks: disease, famine, and war.disease, famine, and war. Darwin based his theoryDarwin based his theory on his own observationson his own observations and the writings ofand the writings of Thomas Malthus.Thomas Malthus. Darwin based his theoryDarwin based his theory on his own observationson his own observations and the writings ofand the writings of Thomas Malthus.Thomas Malthus.
    17. 17. Darwin extended theseDarwin extended these principles to biology, whichprinciples to biology, which helped him form his theory of…helped him form his theory of… Darwin extended theseDarwin extended these principles to biology, whichprinciples to biology, which helped him form his theory of…helped him form his theory of… ……or Survival of the Fittest.or Survival of the Fittest.……or Survival of the Fittest.or Survival of the Fittest.
    18. 18. Natural selection was theNatural selection was the mechanism by whichmechanism by which Darwin proposed thatDarwin proposed that evolution took place.evolution took place. Natural selection was theNatural selection was the mechanism by whichmechanism by which Darwin proposed thatDarwin proposed that evolution took place.evolution took place. Darwin published hisDarwin published his theory in the booktheory in the book Darwin published hisDarwin published his theory in the booktheory in the book
    19. 19. Five basic components ofFive basic components of
    20. 20. 1. All species have genetic variation.1. All species have genetic variation.1. All species have genetic variation.1. All species have genetic variation. Every species is different,Every species is different, even within itself.even within itself. Every species is different,Every species is different, even within itself.even within itself. Variation is caused byVariation is caused by mutations and meiosis.mutations and meiosis. Variation is caused byVariation is caused by mutations and meiosis.mutations and meiosis.
    21. 21. 2.2. Organisms produce more offspring thanOrganisms produce more offspring than can survivecan survive. Many that survive do not. Many that survive do not produce offspring.produce offspring. 2.2. Organisms produce more offspring thanOrganisms produce more offspring than can survivecan survive. Many that survive do not. Many that survive do not produce offspring.produce offspring. The female green sea turtle lays a clutch of aboutThe female green sea turtle lays a clutch of about 110 eggs. She may lay several clutches.110 eggs. She may lay several clutches. The female green sea turtle lays a clutch of aboutThe female green sea turtle lays a clutch of about 110 eggs. She may lay several clutches.110 eggs. She may lay several clutches. It is likely thatIt is likely that less than 1%less than 1% of the hatchlings will everof the hatchlings will ever reach sexual maturity.reach sexual maturity. It is likely thatIt is likely that less than 1%less than 1% of the hatchlings will everof the hatchlings will ever reach sexual maturity.reach sexual maturity.
    22. 22. 3.3. Since more organisms are produced thanSince more organisms are produced than can survive, there iscan survive, there is competitioncompetition (struggle for(struggle for existence)existence).. 3.3. Since more organisms are produced thanSince more organisms are produced than can survive, there iscan survive, there is competitioncompetition (struggle for(struggle for existence)existence).. Competition exists WITHIN and AMONG species.Competition exists WITHIN and AMONG species.Competition exists WITHIN and AMONG species.Competition exists WITHIN and AMONG species. foodfoodfoodfood Within and Among Species for And Within a Species for waterwaterwaterwater matesmatesmatesmates sheltersheltersheltershelter spacespacespacespace
    23. 23. The constant struggle for survival is affected by short-term natural disasters. (drought, fires, floods, snowstorms, hurricanes, and tornadoes) The constant struggle for survival is affected by short-term natural disasters. (drought, fires, floods, snowstorms, hurricanes, and tornadoes) The constant struggle for survival is also affected by long-term changes in the environment. (ice ages, biome shifts, etc) The constant struggle for survival is also affected by long-term changes in the environment. (ice ages, biome shifts, etc)
    24. 24. 4.4. Survival of the fittestSurvival of the fittest Some organismsSome organisms are more suited to their environment as aare more suited to their environment as a result of variations in the species.result of variations in the species. 4.4. Survival of the fittestSurvival of the fittest Some organismsSome organisms are more suited to their environment as aare more suited to their environment as a result of variations in the species.result of variations in the species. Fitness: the ability of an individual tothe ability of an individual to survive and reproduce in its specificsurvive and reproduce in its specific environment. Fitness is a result of adaptations.environment. Fitness is a result of adaptations. Fitness: the ability of an individual tothe ability of an individual to survive and reproduce in its specificsurvive and reproduce in its specific environment. Fitness is a result of adaptations.environment. Fitness is a result of adaptations. He who spreads the most genes wins!He who spreads the most genes wins!He who spreads the most genes wins!He who spreads the most genes wins! 1st Individuals that are fit to their environmentIndividuals that are fit to their environment survive and leave more offspring than thosesurvive and leave more offspring than those who aren’t.who aren’t. Individuals that are fit to their environmentIndividuals that are fit to their environment survive and leave more offspring than thosesurvive and leave more offspring than those who aren’t.who aren’t.
    25. 25. 5.5. Descent with modificationDescent with modification:: Living speciesLiving species today are descended with modifications fromtoday are descended with modifications from common ancestral species that lived in thecommon ancestral species that lived in the past.past. 5.5. Descent with modificationDescent with modification:: Living speciesLiving species today are descended with modifications fromtoday are descended with modifications from common ancestral species that lived in thecommon ancestral species that lived in the past.past. Over time, genes for lessOver time, genes for less favored characteristics will befavored characteristics will be eliminated from the gene pool.eliminated from the gene pool. Over time, genes for lessOver time, genes for less favored characteristics will befavored characteristics will be eliminated from the gene pool.eliminated from the gene pool. Example: giraffes and theirExample: giraffes and their increasingly longer necks.increasingly longer necks. Example: giraffes and theirExample: giraffes and their increasingly longer necks.increasingly longer necks. Characteristics of fit individualsCharacteristics of fit individuals increase in a population over time.increase in a population over time. Characteristics of fit individualsCharacteristics of fit individuals increase in a population over time.increase in a population over time.
    26. 26. Natural Selection: Survival of the FittestNatural Selection: Survival of the FittestNatural Selection: Survival of the FittestNatural Selection: Survival of the Fittest the variation exists first.the variation exists first.the variation exists first.the variation exists first. AnAn adaptationadaptation is any inherited characteristicis any inherited characteristic (a genetic variation) that can increase an(a genetic variation) that can increase an organism’s chance of survival.organism’s chance of survival. AnAn adaptationadaptation is any inherited characteristicis any inherited characteristic (a genetic variation) that can increase an(a genetic variation) that can increase an organism’s chance of survival.organism’s chance of survival. the environment changes.the environment changes.the environment changes.the environment changes. a variation may give an advantagea variation may give an advantage to survive environmental change.to survive environmental change. a variation may give an advantagea variation may give an advantage to survive environmental change.to survive environmental change. An organism does not changeAn organism does not change because of need or desire tobecause of need or desire to survive. The organism eithersurvive. The organism either already has the variation thatalready has the variation that enables it to survive or it dies.enables it to survive or it dies. An organism does not changeAn organism does not change because of need or desire tobecause of need or desire to survive. The organism eithersurvive. The organism either already has the variation thatalready has the variation that enables it to survive or it dies.enables it to survive or it dies.
    27. 27. As the environment changes, organisms mustAs the environment changes, organisms must have variations that allow them to survivehave variations that allow them to survive (adapt) to those changes or die(adapt) to those changes or die As the environment changes, organisms mustAs the environment changes, organisms must have variations that allow them to survivehave variations that allow them to survive (adapt) to those changes or die(adapt) to those changes or die If an entire population ofIf an entire population of a species cannot adapt,a species cannot adapt, that species becomesthat species becomes extinct.extinct. If an entire population ofIf an entire population of a species cannot adapt,a species cannot adapt, that species becomesthat species becomes extinct.extinct.
    28. 28. There have been at least 5 MASS extinctionsThere have been at least 5 MASS extinctions during Earth’s history where a huge % of theduring Earth’s history where a huge % of the living species were destroyedliving species were destroyed There have been at least 5 MASS extinctionsThere have been at least 5 MASS extinctions during Earth’s history where a huge % of theduring Earth’s history where a huge % of the living species were destroyedliving species were destroyed At least one ofAt least one of these has beenthese has been attributed toattributed to meteor impact andmeteor impact and it’sit’s consequences.consequences. At least one ofAt least one of these has beenthese has been attributed toattributed to meteor impact andmeteor impact and it’sit’s consequences.consequences.
    29. 29. It is estimated thatIt is estimated that 1/5 or more of the world’s1/5 or more of the world’s speciesspecies will become extinctwill become extinct if the rainforestsif the rainforests are destroyed.are destroyed. It is estimated thatIt is estimated that 1/5 or more of the world’s1/5 or more of the world’s speciesspecies will become extinctwill become extinct if the rainforestsif the rainforests are destroyed.are destroyed. Many scientistsMany scientists say that thesay that the earth isearth is currentlycurrently experiencing aexperiencing a mass extinctionmass extinction crisis.crisis. Many scientistsMany scientists say that thesay that the earth isearth is currentlycurrently experiencing aexperiencing a mass extinctionmass extinction crisis.crisis.
    30. 30. • What do you think biodiversity is? • ANSWER: the variation of life forms in an ecosystem • How do you think biodiversity would be affected by mass extinction? • ANSWER: biodiversity would decrease significantly Life Variation
    31. 31. If we are in a period of mass extinction . . .If we are in a period of mass extinction . . . What animals will your grandchildren be ableWhat animals will your grandchildren be able to see in the wild?to see in the wild? If we are in a period of mass extinction . . .If we are in a period of mass extinction . . . What animals will your grandchildren be ableWhat animals will your grandchildren be able to see in the wild?to see in the wild? Visit the World Wildlife Fund website for more information on endangered species. Photos by MartinHarvey World Wildlife Fund International
    32. 32. Davis, Donald E. “Meteor Impact”. (Also public domain from NASA.) No date. Online image with permission. Dinosaurs and Their Extinction. June 10, 2004. <http://www.donaldedavis.com/PARTS/DDDINOS.html> Davis, Donald E. “Meteor Impact”. (Also public domain from NASA.) No date. Online image with permission. Dinosaurs and Their Extinction. June 10, 2004. <http://www.donaldedavis.com/PARTS/DDDINOS.html> “Snow Alaska”. No date. Online image. Public Domain. Mineral Management Service. June 10, 2004. GeekPhilospher.com <http://geekphilosopher.com/bkg/snowAlaskaIce.htm> “Snow Alaska”. No date. Online image. Public Domain. Mineral Management Service. June 10, 2004. GeekPhilospher.com <http://geekphilosopher.com/bkg/snowAlaskaIce.htm> “Clearcut in Cameroon Rainforest”. No date. Online image. June 11, 2004. Earth Crash Earth Spirit. <http://www.eces.org/archive/gallery/forestsgfx/forests39.shtml> “Clearcut in Cameroon Rainforest”. No date. Online image. June 11, 2004. Earth Crash Earth Spirit. <http://www.eces.org/archive/gallery/forestsgfx/forests39.shtml> Harvey, Martin. No date. Online image. World Wildlife Fund. June 11, 2004. <http://www.panda.org> Harvey, Martin. No date. Online image. World Wildlife Fund. June 11, 2004. <http://www.panda.org> “Allosaur”. No date. Online image. Public Domain. Dinosaur National Monument. National Park Service. June 10, 2004. http://www.nps.gov/dino/index.htm “Allosaur”. No date. Online image. Public Domain. Dinosaur National Monument. National Park Service. June 10, 2004. http://www.nps.gov/dino/index.htm
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