Download Evolution - Diversity of Life

Evolution - Diversity of Life
Biological Evolution

Essentially the process whereby _______________________ arise from earlier species by
accumulated changes
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Often referred to as ___________________________________

The change in the inherited traits (genotypes/phenotypes) of a species over a period of time is
sometimes called ___________________________

The process of __________________ proceeds with time
o
Increasing numbers of species appear, becoming increasingly ____________________
o
The pattern of this, over time, looks like a branching tree
o
Close clusters of branches/tips are most _____________, or most closely related
History of Evolutionary Thought
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Early Ideas On Earth’s Organisms
o
________________ believed species were _______ creations arranged by their complexity
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Early Ideas On Earth’s Organisms
o
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Idea lasted 2000 years
________________ – 1st to group similar organisms and assign them __________ names
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Two word name (Genus species)
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Known as Binomial nomenclature
Contributor’s to Darwin’s thinking included:
o
o
James Hutton - ______________________
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Scottish geologist who studied invertebrate fossils in Paris Museum
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Changes in the Earth’s crust were due to slow _________________ processes
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___________ changes over a long period of time will produce vast changes
Charles ______________ - Uniformintarianism
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The processes that alter the Earth are ____________ through time...they are still
happening today (erosion of mountains, volcanoes, etc.)

First proposed that the Earth was ___________ of years old, rather than thousands.
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Published his work right before Darwin set sail on his voyage.
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It helped Darwin understand some of the strange things he discovered

o
Ex: Sea shells in the Andes Mountains at 12,000+ feet __________ sea level
Georges Cuvier – ________________________
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Studied fossils in rock strata in Paris
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Found that some _____________ completely disappeared in more recent layers
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Proposed that entire species of organisms had become ______________ due to
catastrophic natural events (erupting volcanoes, floods, etc.)
o
Thomas ______________ – Struggle for existence
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English cleric and scholar, focusing on political economy & demography
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Effects of __________________ growth on society
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Proposed that population size is regulated and limited by available ______________
o
John Baptiste ________________ – Inheritance of acquired Characteristics and Law of Use
and Disuse
o
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Alfred Russel Wallace – organisms evolved from _______________________________
Lamarck’s Theory of Evolution
o
Jean-Baptiste Lamarck, 1809
o
One Of First Scientists To Understand That _______________ Occurs Over ____________
o
Stated that Changes Are __________________ To Environment acquired in an organism’s
lifetime
o
Said acquired changes were passed to offspring
o
Law of _________________________________
o
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If a body part were used, it got stronger
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If a body part NOT used, it deteriorated
Use & Disuse - Organisms Could ____________ The Size Or Shape Of Organs By Using
Them Or Not Using Them
o
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Blacksmiths & Their Sons (muscular arms)
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Giraffe’s Necks (Longer from stretching)
Inheritance of Acquired Characteristics

Proposed That By Selective _______________________ Of Organs, Organisms
Acquired Or Lost Certain Traits During Their Lifetime
o

These Traits Could Then Be Passed On To Their Offspring

Over Time This Led To _____________________
_____________________ Of Acquired Traits

o
Traits Acquired During Ones Lifetime Would Be Passed To Offspring
Tendency Toward ___________________

Organisms Are Continually Changing and Acquiring Features That Help Them Live
more ________________________ In Their Environment

Example: Bird Ancestors Desired To Fly So They Tried Until Wings
Developed. Then their offspring were born with wings.
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Lamarck’s Mistakes
o
Lamarck Did NOT Know how traits were _____________ (Traits are passed through genes)
o
Genes Are _______ Changed By Activities In Life
o
Change Through ________________ Occurs Before An Organism Is Born
Charles Darwin the Naturalist
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Born Feb. 12, _________
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Joined Crew of HMS Beagle, ________
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Naturalist
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_____Year Voyage around world
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Avid Collector of Flora & Fauna
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Astounded By Variety of Life
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Darwin did not foresee himself getting into the field of evolutionary biology.

He wanted to be a ___________ like his father, but he could not stand the sight of blood and the
savagery of surgery.

He then wanted to be a ______________, but he did not want to study. He preferred riding and
shooting to studying.

He eventually became interested in ______________ through his fascination with such animals as
barnacles, beetles and pigeons.
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He changed his path at college and took more biology courses as he developed a great love of
_________________ (yes, the classification stuff!)

A professor recommended Darwin for work as an unpaid ______________ on a voyage around the
world upon the ____________________, under captain Robert Fitzroy.
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This journey not only changed Darwin’s life, but also the face of biology forever…
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Darwin Left England in 1831 and returned 5 years later in 1836
The Galapagos Islands
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Small Group of ________________________ 1000 km West of South America
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Very Different Climates from the surrounding area
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Animals on the Islands were Unique
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___________________
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Iguanas
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___________________
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Island species ____________ from mainland species & varied from island-to-island
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Each island had tortoises with different __________ types and ___________ lengths
o
They were unique to their particular island
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________________ on the islands resembled a mainland finch

_____________________ of finches appeared on the islands where the available food was
different (seeds, nuts, berries, insects…)

Finches had different types of _____________ adapted to their type of food gathering
Darwin’s Observations & Conclusions - The Struggle for Existence
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Darwin’s Observations
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Patterns of _____________________ were seen
o
He observed Unique ______________________ in organisms
o
Species Were Not Evenly ________________________

Australia had Kangaroos, but No Rabbits
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S. America had Llamas
o
Both Living Organisms & _____________ were collected
o
Fossils included:
o
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Trilobites
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Giant _______________________ of South America
Left unchecked, the number of organisms of each species will increase
____________________, generation to generation
o
But in nature, populations tend to remain ____________ in size
o
Environmental resources are ________________
o
Individuals of a population _________ extensively in their characteristics with no two
individuals being ______________________.
o

Much of this variation between individuals is ____________________.
Darwin’s Conclusion
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Production of more individuals than can be supported by the environment leads to a
________________________________ among individuals
o
Only a fraction of offspring survive each generation
o
___________________________________
o
Individuals who inherit characteristics ________________ for their environment are likely to
leave more offspring than less fit individuals
o
Called _________________________________
Darwin’s Theory of Evolution - Organisms Change Over Time

The unequal ability of individuals to __________ and _________________ leads to a gradual
change in a population, with favorable characteristics accumulating over generations (natural
selection)
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New ______________ evolve
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Evolution is the __________________________ change in a population of organisms
_______________________
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Common Descent with Modification
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Darwin proposed that organisms descended from _________________________________
o
The idea that organisms ___________ with time, diverging from a common form
o
Caused evolution of new ______________
Descent With Modification
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Takes Place Over _________ Periods of Time
o
______________________________ Can Be Observed As Changes In
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Body Structures
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Ecological Niches
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Habitats
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Species Today Look _________________ From Their Ancestors
o
Each Living Species Has
o
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_________________
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With Changes
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From Other Species
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__________________
Implies
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All Living Organisms Are _______________

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All Species, Living & Extinct, Were Derived From ______________________
Single Tree of Life
Natural Selection
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_____________________________ is the Driving force for evolution.

During the struggle for resources, the strongest (most fit) survive & reproduce
o
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___________________________
He had the idea that at least some of the differences between individuals, which impact their
survival and fertility, were ____________________

Survival of the Fittest
o
o
Fitness
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Ability of an Individual To ________________________________

Central To The Process Of Evolution
_______________________

Inherited Characteristic That Increases an Organisms Chance for Survival

Adaptations can be

_________________
o
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Speed, Camouflage, Claws, Quills, etc.
_________________
o
Solitary, Herds, Packs, Activity, etc.
Evolutionary Time Scales
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_______________________ - Long time scale events that create and destroy species.
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_______________________ - Short time scale events (generation-to-generation) that change the
genotypes and phenotypes of populations.