Download Theory of Evolution (Natural Selection)

Theory of Evolution (Natural Selection)

Ideas of Evolution – first published by __________________ and now the basis of the
_______________________________.

HMS Beagle an English Ship – at the _________ Darwin took a job as a ______________.
It was a ____ journey where collected __________ specimens at every port

______________ a group of small islands that was of great interest to Darwin. He made
____________ of _____________ of animals and _________________________
________________________________________________________________

Next 22 yrs – Darwin worked to find an ________ for how ______ could ______over time.
He modified the ideas of _________________ (who was studying how ______________
was growing faster than Earth’s food supply).
Darwin & 2Types of Selection:

Artificial Selection: _______ provides the ________ but _________ select those
______________that they found _____________

Natural Selection: when organisms with certain variations _______________________
variations to the ___________________ “Survival of the Fittest.”
o 3 Types of Natural Selection

Stabilizing: favors __________ individuals in a population;
ex: _________________________________________________

Directional: favors _________________________ variations of a trait;
ex: __________________________________________________

Disruptive: favors individuals with _______________________ of trait
ex: ________________________ limpets blend in with light and dark rock
2 Types of Adaptation:

Structural Adaptations: Arise _________________ ex: teeth, claws, thorns
o Mimicry – enables one species to _______________ another
o Camouflage – enables species to ___________ with their surrounding

Physiological Adaptations: can develop ___________; changes _______processes (___)
ex: Bacterial Resistance to Penicillin ____________________
Evidence for Evolution
1)
Fossils – provide a ___________ of _____________ and evolutionary history
2)
Anatomy – structural ______________

Homologous Structures: similarities in ___________ (look ______,
different __________) ex: ____________________

Analogous Structures: similarities in __________ (look ___________;
same _____________) ex: ___________________________

Vestigial Structures: body structures that have no function in ________
organism; probably _____________. ex: ______________________
3)
Embryology – similarities in the ________________ of growth and development
ex: _______________________________ it is difficult to distinguish embryos
4)
Biochemistry – comparison of the ______________________ sequences.
*All evidence only shows _________________
Mechanisms of Evolution

Populations – consists of ______________ of a _______ that live in that area;
evolution occurs as a ________________ change over time ________________
o Gene Pool – all the ______ in a population
o Allelic Frequency – percentage of any specific allele in a _____________
(Hardy Weinberg Principle = p2+2pq+q2=1)
Genetic Equilibrium – population’s genes remains the _______ (not evolving)

Changes in Genetic Equilibrium:
1) Natural Selection: Survival of the Fittest – _____________________
2) Mutation: changes in __________________; many are lethal
3) Genetic Drift: alterations of alleles by __________events; usually in
_____________________ populations ex: _______________
4) Gene flow: movement of individuals ________________ of a population
Evolution of a species?? How??

Species – ________that look alike; can __________ to produce _______ offspring

Speciation – evolution of _________; occurs when members of similar population __
__________________ to produce _________________________
o Causes of speciation

Geographic Isolation – when two ____________ are _____________
by _____________ barriers ex: ______________________

Behavioral Isolation – when two populations are __________ of
_________________ but have differences in _________________

Temporal (Reproductive) Isolation - when species ________________
at ________ times ex: ____________________________________

Polyploidy – multiple sets of __________
Patterns of Evolution

Divergent Evolution – where species that were _____________ become different
o Adaptive Radiation - _________ evolution that occurs when a species evolves
into an ____________ to fit ____________ ex: ____________________

Convergent Evolution – when _________ related organisms evolve __________ traits
due to ______________________ ex: ______________________