Download Ch. 22-Student Note Sheet

Name ____________________________________ Date ____________ Period _____
Darwin and Evolution by Natural Selection
Raven Ch. 1 and 22
Big Idea 1: THE PROCESS OF EVOLUTION DRIVES THE DIVERSITY AND UNITY OF LIFE.
It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is the most adaptable to
change.
― Charles Darwin (1859)
Essential Knowledge:
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Natural selection is a major mechanism of evolution
Natural selection acts on phenotypic variations within populations.
Evolutionary change is also driven by random processes.
Biological evolution is supported by scientific evidence from many disciplines including mathematics
Organisms share many conserved core processes and features that evolved and are widely distributed among
organisms today.
Phylogenetic trees and cladograms are graphical representations (models) of evolutionary history that can be
tested
Speciation and extinction have occurred throughout the Earth’s history.
Speciation may occur when two populations become reproductively isolated from each other.
Populations of organisms continue to evolve.
There are several hypotheses about the origin of life on Earth, each with supporting scientific evidence.
Scientific evidence from many different disciplines supports models of the origin of life.
Natural selection is a major mechanism of evolution
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What was the doctrine of the time? _______________________________________________________
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Pre-Darwin: Ideas accepted before Darwin
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Jean-Baptiste LaMarck (
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o
Naturalist
o
Organisms adapted to their environments by ________________________ traits
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change in their life time
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________________
-organisms lost parts because they did not use them — like the missing eyes &
digestive system of the tapeworm
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_______________________________________________
-the constant use of an organ leads that organ to increase in size — like the muscles
of a blacksmith or the large ears of a night-flying bat
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transmit acquired characteristics to next generation
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Lyell (
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Wrote- Principles of Geology
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Outlined the story of ancient world of plants and animals in flux
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Malthus (
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Wrote- Essay on the Principle of Population
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Studies of ___________________ limited by _____________________
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Malthusian catastrophe
Father of Evolution by Means of Natural Selection
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Charles Darwin (
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British naturalist
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Proposed the idea of _______________________________________
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Collected clear _______________________________ to support his ideas
Voyage to the _____________________________________
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Galapagos Observations:
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Examples of endemic species:
________________________,
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Adaptive radiation- Rapid ____________________: new species filling new _______________,
because they inherited _____________________________________________________.
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Why? Correlation of species to food source
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Darwin’s Finch:
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Differences in beaks allowed some finches to…
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successfully __________________
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successfully __________________
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successfully __________________
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__________________ successful traits onto their
_____________________
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Galapagos Turtles:
o
What morphological difference? _________________________________________
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Many islands also show distinct local variations in tortoise morphology
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Why? Correlation of species to habitat
…perhaps these are the first steps in the splitting of ______________ into ____________?
(Speciation!!)
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Fossils:
o
Examples: _________________________ and _______________________________
…Why should extinct species & living species be found on the same continent??? –Darwin
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Artificial Selection (Selective Breeding):
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Changes in morphology…not just a process of the past…it is all around us today!
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Examples: _________________________, _______________________________,
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Hidden ______________________ can be exposed through __________________________!
Darwin after the Galapagos voyage
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A Reluctant R[evolution]ary
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Returned to England in 1836
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wrote papers describing his collections & observations long treatise on barnacles
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draft of his theory of species formation in 1844
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instructed his wife to publish this essay upon his death
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reluctant to publish but didn’t want ideas to die with him
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_______________________________ -a young naturalist working in the East Indies, had written a short
paper with a new idea. He asked Darwin to evaluate his ideas and pass it along for publication. (1858)
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Darwin’s book: “On the Origin of Species by Means of Natural Selection”
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Published ____________________________
Essence of Darwin’s ideas
o
Evolution by Means of Natural Selection
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_______________________________ exists in populations
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_______________________________ -more offspring than the environment can
support
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_______________________________ -for food, mates, nesting sites, escape predators
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_______________________________ -successful traits = adaptations
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_______________________________ -adaptations become more common in
population
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