EvolutionEvolutionDiversity of LifeDiversity of Life

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Bell RingerBell Ringer

Name two of the unique species that Name two of the unique species that Darwin observed on his voyage.Darwin observed on his voyage.

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Bell RingerBell Ringer

How did the geologists of his time How did the geologists of his time influence Darwin’s understanding influence Darwin’s understanding of the world.of the world.

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Bell RingerBell Ringer

Why was Lamarck’s theory of Why was Lamarck’s theory of evolution incorrect?evolution incorrect?

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Daily ObjectivesDaily Objectives

Describe the ideas that influenced Describe the ideas that influenced Darwin’s scientific understanding. Darwin’s scientific understanding.

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““Nothing in Nothing in biology makes biology makes

sense EXCEPT in sense EXCEPT in the light of the light of evolution.evolution.””

Theodosius Theodosius DobzhanskyDobzhansky

Evolution

Charles Darwin in later yearsCharles Darwin in later years

Evolutionary Evolutionary TimelineTimeline

Early Ideas On Early Ideas On Earth’s OrganismsEarth’s Organisms

Aristotle believed Aristotle believed species were fixed species were fixed creations arranged creations arranged by their complexityby their complexity

Idea lasted Idea lasted 20002000 yearsyears

This arrangement This arrangement is like a is like a ladderladder

Early Ideas On Early Ideas On Earth’s OrganismsEarth’s Organisms

Linnaeus – First person Linnaeus – First person to group similar to group similar organisms and assign organisms and assign them Latin namesthem Latin names

Two word name Two word name (Genus species)(Genus species)

Known as Binomial Known as Binomial nomenclaturenomenclature

Example of Binomial Example of Binomial NomenclatureNomenclature

CatastrophismCatastrophism

Idea proposed by George Idea proposed by George CuvierCuvier

Studied fossils in sedimentary Studied fossils in sedimentary rock strata of Parisrock strata of Paris

Found some species Found some species completely disappeared in completely disappeared in more recent layersmore recent layers

CatastrophismCatastrophism

Stated that species Stated that species disappear due to a disappear due to a catastrophic event of catastrophic event of the earth’s crust the earth’s crust

Ex. (volcano, Ex. (volcano, earthquake, flood, etc)earthquake, flood, etc)

Hutton’s Theory of Hutton’s Theory of Geological ChangeGeological Change

James Hutton, 1795, James Hutton, 1795, Scottish geologistScottish geologist

Described the geological Described the geological forces that have changed life forces that have changed life on earth over millions of on earth over millions of years years

(erosion, earthquakes, (erosion, earthquakes, volcanoes…)volcanoes…)

Hutton’s Theory of Hutton’s Theory of Geological ChangeGeological Change

Changes in Earth’s Changes in Earth’s crust are due to crust are due to slow, continuous slow, continuous processesprocesses

This idea is known This idea is known as: Gradualismas: Gradualism

Charles LyellCharles Lyell

Proposed theory of Proposed theory of UniformintarianismUniformintarianism

Geological processes Geological processes occur at uniform occur at uniform (constant) rates building (constant) rates building & wearing down Earth’s & wearing down Earth’s crustcrust

Proposed that the Earth Proposed that the Earth was millions of years old was millions of years old instead of a few instead of a few thousand years oldthousand years old

Principles of GeologyPrinciples of GeologyPublished by Lyell just before Published by Lyell just before

the Beagle set sail & it was the Beagle set sail & it was read by Darwinread by Darwin

Explained geological Explained geological processes that shaped the processes that shaped the earthearth

Helped Darwin understand Helped Darwin understand sea shells in the Andes sea shells in the Andes Mountains at 12,000+ feetMountains at 12,000+ feetExpanded Earth’s AgeExpanded Earth’s Age

Lamarck’s Theory of Lamarck’s Theory of EvolutionEvolution

Jean-Baptiste Lamarck, Jean-Baptiste Lamarck, 18091809

One of first scientists to One of first scientists to understand that change understand that change occurs over timeoccurs over time

Stated that changes are Stated that changes are adaptations to the adaptations to the environment acquired in environment acquired in an organism’s lifetimean organism’s lifetime

Said acquired changes Said acquired changes were passed to offspringwere passed to offspring

LamarckLamarck’’s Theory of s Theory of EvolutionEvolution

Idea called Law Idea called Law of Use and of Use and DisuseDisuse

If a body part If a body part was used, it got was used, it got strongerstronger

If body part was If body part was NOT used, then NOT used, then it deterioratedit deteriorated

Lamarck’s Theory of Lamarck’s Theory of EvolutionEvolution

Examples of Use Examples of Use and Disuseand Disuse

Blacksmiths & Blacksmiths & Their Sons Their Sons (muscular arms)(muscular arms)

Giraffe’s Necks Giraffe’s Necks Longer (from Longer (from stretching)stretching)

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Lamarck’s Theory of Lamarck’s Theory of EvolutionEvolution

Inheritance Of Acquired TraitsInheritance Of Acquired TraitsTraits acquired during ones Traits acquired during ones

lifetime would be passed to lifetime would be passed to offspringoffspring

Lamarck’s Theory of Lamarck’s Theory of EvolutionEvolution

Tendency toward perfectionTendency toward perfection

Organisms are continually Organisms are continually changing and acquiring features changing and acquiring features that help them live more that help them live more successfully in their environmentsuccessfully in their environment

Example: Bird ancestors desired Example: Bird ancestors desired to fly so they tried until wings to fly so they tried until wings developeddeveloped

Lamarck’s MistakesLamarck’s Mistakes

Did NOT Know how traits Did NOT Know how traits were inherited (Traits are were inherited (Traits are passed through genes)passed through genes)

Genes are not changed by Genes are not changed by activities in lifeactivities in life

Change through mutation Change through mutation occurs before an organism is occurs before an organism is bornborn

Population GrowthPopulation Growth

Thomas Malthus, 1798Thomas Malthus, 1798

EconomistEconomist

Observed babies being born Observed babies being born faster than people were dyingfaster than people were dying

Human population size is Human population size is limited by resources such as limited by resources such as the food supplythe food supply

The Struggle for The Struggle for ExistenceExistence

Malthus’ Influence on Darwin:High Birth Rates & Limited High Birth Rates & Limited

Resources Would Force Life Resources Would Force Life & Death Competition& Death Competition

Each Species Struggles For:FoodFoodLiving SpaceLiving SpaceMatesMates

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Evolutionary Evolutionary TimelineTimeline

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