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•Who developed the theory of acquired characteristics? a. Darwin b. Lamarck c. Charles Lyell d. Aristotle

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•Who developed the theory of natural selection, and survival of the fittest? a. Darwin b. Lamarck c. Charles Lyell d. Aristotle

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•True or False •Evolution happens very quickly.

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Organisms with the best traits fit for survival tend to have more offspring and this trait accumulates over generations. This is known as: a. Darwinism b. Natural Selection c. The theory of use and disuse d. Struggle for existence

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•Which Islands are most famous for Darwin’s discoveries? •A. Australia •B. Hawaii •C. Galapagos •D. Japan

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Darwin’s Theory of Evolution Organisms Change OverTime

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Common Descent with Modification

• Darwin proposed that organisms descended from common ancestors

• Idea that organisms change with time, diverging from a common form

• Caused evolution of new species

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Natural Selection

• Driving force for evolution • During the struggle for

resources, strongest survive & reproduce

• Idea that at least some of the differences between individuals, which impact their survival and fertility, are inheritable

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Origin of Species

Darwin Presents His Case

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Publication of “On The Origin of Species”

• Upon His Return To England, Darwin Developed His Observations Into The Theory of Evolution

• But He Did Not Publish For 25 Years –

Why?

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Publication of “On The Origin of Species”

• Darwin Knew That His Theory Would Be Extremely Controversial And Would Be Attacked

• His Theory Challenged Established Religious & Scientific Beliefs, Particularly About The Creation Of Man

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Publication of “On The Origin of Species”

• He Refused To Publish Until He Received An Essay From Alfred Wallace

– Fellow Naturalist

– Independently Developed The Same Theory

– After 25 Years, Someone Else Had Come To The Same Conclusions From Their Observations Of Nature

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Wallace’s Contribution

• Alfred Russel Wallace Independently came to same Conclusion as Darwin that species changed over time because of their struggle for existence

• When Darwin read Wallace’s essay, he knew he had to publish his findings

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Natural Variation and Artificial Selection

• Natural Variation

–Differences Among Individuals Of A Species

• Artificial Selection

– Selective Breeding To Enhance Desired Traits Among Stock or Crops

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Natural Variation and Artificial Selection

Key Concept:

In Artificial Selection, Nature Provided The Variation Among Different Organisms, And Humans Selected Those Variations That They Found Useful

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Origin of Species

Concepts and Controversy

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Evolution By Natural Selection Concepts

• The Struggle for Existence (compete for food, mates, space, water, etc.)

• Survival of the Fittest (strongest able to survive and reproduce)

• Descent with Modification (new species arise from common ancestor replacing less fit species)

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Survival of the Fittest

• Fitness

– Ability of an Individual To Survive & Reproduce

• Adaptation

– Inherited Characteristic That Increases an Organisms Chance for Survival

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Survival of the Fittest

• Adaptations Can Be:

–Physical

• Speed, Camouflage, Claws, Quills, etc.

–Behavioral

• Solitary, Herds, Packs, Activity, etc.

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Survival of the Fittest

• Fitness Is Central To The Process Of Evolution

• Individuals With Low Fitness

–Die

–Produce Few Offspring

Survival of the Fittest

AKA Natural Selection

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Survival of the Fittest

Key Concept Over Time, Natural Selection Results In

Changes In The Inherited Characteristics Of A Population. These Changes Increase A Species Fitness In Its Environment

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Natural Selection

• Cannot Be Seen Directly

• It Can Only Be Observed As Changes In A Population Over Many Successive Generations

–Radiation

– Fossil Record

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Descent With Modification

• Takes Place Over Long Periods of Time

• Natural Selection Can Be Observed As Changes In

–Body Structures

– Ecological Niches

–Habitats

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Descent With Modification

• Species Today Look Different From Their Ancestors

• Each Living Species Has –Descended With Changes From Other

Species Over Time

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Descent With Modification

Homologous Structures: Similar Structures that suggest evolution from a common ancestor.

analogous structures are features of different species that are similar in function but not necessarily in

structure and which do not derive from a common ancestral feature

Vestigial refers to an organ or part (for example, the human appendix) which is greatly reduced from the

original ancestral form and is no longer functional or is of reduced or altered function.

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Major Problem in Darwin’s Theory

• No mechanism to explain natural selection

• How could favorable variations be transmitted to later generations?

• With the rediscovery of Mendel’s work in the first half of the 20th century, the missing link in evolutionary theory was found

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Opposition to Evolution

• The upheaval surrounding evolution began with Darwin’s publication of On the Origin of Species By Means of Natural Selection

• The debate continues nearly 150 years later

Why, according to our reading, did Darwin take so long to publish the Origin of Species?

A. Darwin wanted to share his theory as quickly as possible once he returned from his voyage on the Beagle.

B. It took twenty years for Darwin to develop a theory.

C. Darwin suffered from a number of illnesses.

D. Darwin was concerned about the reaction of others to the implications of his theory.

E. All of the above.

• In which of the following ways is natural selection not similar to artificial selection?

• A. With natural selection "picking" is due to the fit of an organism with its environment; whereas in artificial selection, the breeder "picks" which organisms will breed.

• B. Natural selection depends upon the presence of variation, artificial selection does not.

• C. Natural selection occurs within populations, artificial selection does not.

• D. There is a limit to how much change can be brought about by natural selection, no such limit exists for artificial selection.

• E. None of the above.

In relation to natural selection, evolution is the a. Process b. Outcome c. Mechanism d. purpose

A salamander living in a cave has no eyes, this is an example of:

a. Homologous structures

b. Analogous structures

c. Vestigial structures

d. All of the above

e. None of the above

• A bird wing and a butterfly wing would be an example of:

a. Homologous structures

b. Analogous structures

c. Vestigial structures

d. All of the above

e. None of the above

• The beak shape of Darwin’s finches was influenced by:

• A. Number of offspring produced in a given year.

• B. Carrying capacity of the environment

• C. Response to the nature of the food supply

• D. Affects of Artificial selection on the island

• E. Predators preying on a specific species of bird.