Download Ch. 22-Evidence for Evolution Notesheet

Name ____________________________________ Date ____________ Period _____
Evidence for Evolution by Natural Selection
Raven Ch. 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
What are the 4 lines of evidence that support Darwin’s ideas?…
1. Fossil Record
Transitional Fossils
Evolution of ____________________
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_________________________-, the earliest known flying bird from the Late Jurassic period,
exhibits many shared primitive characters with therapod (bird-like) dinosaurs. such as teeth, a long
bony tail and pinnate feathers. However, Archaeopteryx possessed asymmetrical flight feathers on
its wings and tail, together with a wing feather arrangement shared with modern birds. This
suggests some degree of powered flight capability but, until now, little was understood about the
extent to which its brain and special senses were adapted for flight.
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lived about 150 mya
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links __________________________________
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Evolution of _____________________
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2006 Fossil Discovery of Early Tetrapod
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“________________________________”
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“______________________” from sea to land animals
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from ____________________ (0 legs) to __________________ (4 legs)
Evolution of _______________ ___________
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Whales as land creatures returning to the __________
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4-5 intermediate forms all found in last 2 decades
Notes on video: ______________________________
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2. Artificial Selection
Examples: __________________________,
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Insecticide and drug resistance:
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insecticide ____________ _____all individuals
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resistant survivors ______________________
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resistance is ___________________________
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insecticide becomes less & less ____________________
Examples: __________________________,
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3. Anatomical Evidence
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Homologous structures
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Similar _________________________
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Similar _________________________
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Different ________________________
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Evidence of close _______________________________
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recent __________________________________
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Examples: Animals____________________________,
____________________________,
____________________________,
____________________________,
____________________________,
Plants-__________________________, ____________________________,
__________________________, __________________________, ________________________,
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Analogous structures
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Solving a similar _____________________ with a similar ___________________________
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Do they have a recent common ancestor? ____________
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A result of ________________________________________
Examples: 1. __________________________ and __________________________________
2. __________________________ and __________________________________
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Convergent Evolution
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Vestigial structures
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Mammals- _____________________________ v. ________________________________
These are _____________________ of structures that were functional in ______ ________
Examples: __________________________, _____________________________________,
4. Molecular Record
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Comparing ______________ & ___________ structure
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______________________ genetic code!
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DNA & RNA
Compare ______________________ genes
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______________________C (respiration)
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____________________ (gas exchange)
Closely related species have sequences that are ____________________ than distantly related
species
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The sequence in DNA & proteins is a _____________________ record of evolutionary
______________________.
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Why compare these genes? _____________________________________________________
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What can we do with the results of these comparisons among organisms?
______________________________________________________________
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Essence of Darwin’s ideas
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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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