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Chapter 17. Pop Genetics and Evolution - Coggle Diagram
Chapter 17. Pop Genetics and Evolution
Population Genetics
Population Genetics
Diff alleles in a population
increases, decreases, same
population concept of species
height,color etc
type concept of species
single ideal specimen
gene pool
total # of alleles
of all individuals in a pop
Factors that cause the gene pool to change
Mutation
existing alleles decrease
new alleles increase
Accidents
events
organism can't adapt
volcanoes, floods, meteroite
Artificial Selection
humans purposefully change
gene pool
selective breeding
crops
animals
Natural Selection
survival of the fittest
Factors that are Not Part of Natural Selection
Purpose
Intention
Planning
Voluntary decision making
Situations in which Natural Selection Does Not Operate
all individuals of a population
identical genetically
Cannot adapt to certain conditions
Multiple Selection Pressures
Speciation
Speciation
natural selection
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phyletic speciation
one species gradually becomes so changed
becomes new species
divergent speciation
some populations of a species evolve
new second species
other stay unchanged
evolve into new third species
Phyletic Speciation
Gene flow
movement of alleles
physically through space
Pollen Transfer
Wind distributed
Animal mediated
Seed Dispersal
Wind
Floods
Stream flow
Vegetative Propagation
small, mobile pieces
Divergent Speciation
reproductively isolated
Abiological Reproductive Barriers
abiological reproductive barier
any
physical
non-living feature
prevents two pops from exchanging genes
allopatric
speciation results
geographic speciation
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Biological Reproductive Barriers
biological reproductive barrier
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any biological phenomenon
prevents successful gene flow
sympatric speciation
two groups
re-productively isolated
prezygotic isolation mechanisms
neither pollination
nor fertilization occurs
postzygotic internal isolation barriers
separate species
hybrid sterility
two populations
interbreed
cross pollinated
seed becomes sterile
hybrid inviability
zygote or embryo dies early in development
Adaptive Radiation
adaptive radiation
species rapidly diverges
many new species
founder individuals
small gene pool
offspring resemble the first
founder
two sets of alleles
Convergent Evolution
resemble each other strongly
Evolution and the Origin of Life
Chemo-synthesis
model the origin of life
using only chemical and physical processes
rejects divine intervention
Conditions on Earth Before the Origin of Life
Chemicals Present in the Atmosphere
second atmosphere
produced by release of gases
from the rock matrix composing earth
heavy bombardment by meteorites
reducing atmosphere
lack of molecular oxygen
powerful reducing agents
Time Available for the Origin of Life
Chemicals Produced Chemosynthetically
S. Miller
University of Chicago
1953
What has happened in nonliving environment
Formation of Polymers
Aggregation and Organization
Early Metabolism
Oxygen
UV light
ozone
Transition made terrestrial life possible
The Presence of Life
inorganic compounds
to living bacteria
physics between the two is identical
Rates of Evolution
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