Download divergent evolution

BIG IDEA 1:
EVOLUTION REVIEW
Chapters 22-24
By Kelly Riedell
Brookings Biology
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing © 2006
Ability of an organism to survive and
reproduce in a specific environment
fitness
How is evolutionary fitness different
than fitness when exercizing at the
gym?
Evolutionary fitness is measured by reproductive
success: number of offspring left behind;
Fitness at the gym describes physical prowess
and/or cardiovascular health
Essential knowledge 1.A.1. b. Evolutionary fitness is measured by reproductive success.
Essential knowledge 1.A.1.e . e. An adaptation is a genetic variation that is favored by selection and is manifested as a trait that provides an advantage to an
organism in a particular environment.
Any inherited characteristic that
increases and organism’s chances
to survive and reproduce.
adaptation
Give some examples of the above
Webbed feet, camouflage, beaks, claws,
speed, venom, living in groups, wings,
blubber, flippers, scales, jaws, hair/fur,
. . .
Essential knowledge 1.A.1.e. An adaptation is a genetic variation that is favored by selection and is manifested as a trait that provides an
advantage to an organism in a particular environment.
By discharging electric sparks into a laboratory chamber atmosphere
that consisted of water vapor, hydrogen gas, methane, and ammonia,
Stanley Miller obtained data that showed that a number of organic
molecules, including many amino acids, could be synthesized. Miller was
attempting to model early Earth conditions as understood in the
1950s. The results of Miller's experiments best support which of the
following hypotheses?
(A) The molecules essential to life today did not exist at the time
Earth was first formed.
(B) The molecules essential to life today could not have been
carried to the primordial Earth by a comet or meteorite.
(C) The molecules essential to life today could have formed under
early Earth conditions.
(D) The molecules essential to life today were initially selfreplicating proteins that were synthesized approximately four
Sample MC questions from
billion years ago.
2015 Course and Exam Description Book
posted on College board website
1.D.1: There are several hypotheses about the natural origin of life on Earth, each with supporting scientific evidence.
SP 3.3: The student can evaluate scientific questions
LO 1.28: The student is able to evaluate scientific questions based on hypotheses about the origin of life on Earth.
Describe the main points of Darwin’s
theory of evolution
Natural variation in population provides basis
for natural selection to act
Overproduction of offspring forces
competition for resources (struggle for survival)
Organisms best suited to their environment will survive
and reproduce; Other organisms die or leave fewer
offspring (survival of the fittest/natural selection)
Species alive today have descended with modification
from ancestral species that lived in the distant past
All organisms are united into a single “tree of life”
(common descent)
Essential knowledge 1.A.1: Natural selection is a major mechanism of evolution.
a. According to Darwin's theory of natural selection, competition for limited resources results in differential survival. Individuals with more favorable phenotypes are
more likely to survive and produce more offspring, thus passing traits to subsequent generations.
Change in a population over time
evolution
Differences among individuals
within a species
Natural variation
Preserved remains of an ancient
organism
fossil
Islands that Darwin visited on his
voyage on the Beagle that started
him thinking about how organisms
change over time
Galapagos
http://www.dwm.ks.edu.tw/bio/activelearner/19/ch19summary.html
http://www.zwani.com/graphics/antivalentines_day/images/4heart.gif
http://www.horton-szar.net/clipart/animals4.php
One species of spotted skunk mates in
late summer, and another mates in
late winter. This is an example of a
_____
pre zygotic reproductive barrier
temporal isolation
called _________
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic
mechanisms can maintain reproductive isolation and prevent gene flow.
Concept that each living species
has descended with changes
from other species over time
Descent with Modifications
Idea that organisms that are
best suited to their environment
will survive and reproduce
Survival of the Fittest
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006
Type of distribution curve shown by
polygenic traits
Bell-shaped curve
(OR normal distribution)
GIVE AN EXAMPLE OF A
PHYSICAL ADAPTATION
Webbed feet, horns, antlers,
claws, feathers, wings, camouflage,
. . . . there are a million
GIVE AN EXAMPLE OF A
BEHAVIORAL ADAPTATION
Nocturnal (coming out at night);
Flying south for the winter, living in herds,
“wagon train” defense; burrowing; hibernation
1.A.1.e. An adaptation is a genetic variation that is favored by selection and is manifested as a trait that provides an advantage to an organism in a
particular environment
When humans select and breed
animals with certain useful
traits from the natural
variation in the population
Artificial selection
Process by which unrelated
organisms independently evolve
similarities when adapting to
similar environments
Convergent evolution
Book published by Charles Darwin
in which he proposed a mechanism
and provided evidence for his
Theory of Evolution
“On the Origin of Species by Natural Selection”
Process by which related organisms
evolve differences when they are
isolated in different environments
Divergent evolution
Naturalist who gave Darwin incentive to
publish his ideas about evolution by
writing an essay that described similar
ideas.
Alfred Russel Wallace
French naturalist who hypothesized
that organisms acquire traits during
their lifetime through use or disuse
which can be passed on to offspring
Jean-Baptiste Lamarck
Explain what was incorrect about Lamarck’s
Inheritance of Acquired Traits
hypothesis
Genes determine which traits are passed on;
unless genes are changed the acquired trait will
only show in the original organism
Explain what was correct about Lamarck’s
Inheritance of Acquired Traits
hypothesis
First theory about evolution;
Organisms do change and adapt to their
environments
http://www.dwm.ks.edu.tw/bio/activelearner/19/ch19summary.htm
http://www.webweaver.nu/clipart/insects2.shtml
Male fireflies of one species signal
females of the same species by
blinking their lights in a specific
pattern. Other firefly species
have different patterns. This is
pre zygotic
an example of a _____
reproductive barrier called
Behavioral
______________
isolation
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic
mechanisms can maintain reproductive isolation and prevent gene flow.
Name 3 kinds of evidence that
supports Darwin’s THEORY OF
EVOLUTION
Fossils
Geographic distribution
Homologous structures
Vestigial organs
Embryology
DNA
Pseudogenes
Artificial selection
Can see natural selection work
antibiotic resistance, new diseases,
http://www.dwm.ks.edu.tw/bio/activelearner/19/ch19summary.html
http://www.zwani.com/graphics/antivalentines_day/images/4heart.gif
http://www.animalpicturesarchive.com/animal/
One species of garter snake is primarily
aquatic, while another closely related
species is primarily terrestrial.
pre zygotic
This is an example of a ____
reproductive barrier called
______________
isolation
Habitat
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic
mechanisms can maintain reproductive isolation and prevent gene flow.
The idea that all species, living
and extinct, were derived from
a common ancestor
Common descent
What Darwin called natural
selection?
Survival of the fittest
Measuring lima beans and finding
beans come in different sizes is
an example of
Natural variation
____________
The practice of breeding dogs to
produce offspring with specific
traits is an example of
artificial
selection
_________________
A human’s appendix and a
skink’s legs are examples of
_______________
Vestigial organs
How would Lamarck
explain these giraffes
with longer necks?
Giraffes stretched their necks to
reach food in tall trees and this
acquired characteristic is passed
on to their offspring.
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing © 2006
How would Darwin explain these
giraffes with longer necks?
Populations naturally have
individuals with different
sizes of necks
(natural variation)
The ones with longer necks
are better able to get food,
survive, and pass on their longer
neck alleles.
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing © 2006
Evolutionary change on the smallest
scale like new strains of HIV
evolving from current HIV virus is
micro evolution
called ______
micro
macro
Which variable is used to represent
the frequency of the dominant
allele in a Hardy Weinberg
problem?
p
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Application of the Hardy-Weinberg equilibrium equation
4.C.3. c. Allelic variation within a population can be modeled by the Hardy- Weinberg equation(s).
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing © 2006
According to this diagram, modern
whales have a vestigial pelvis
and femur. What does this suggest
about ancestors of modern whales?
Ancestors of modern
whales had legs and
walked on land
1.A.4.b.2. Morphological homologies represent features shared by common ancestry.
Vestigial structures are remnants of functional structures, which can be compared to fossils and provide evidence for evolution
http://www.angelfire.com/ab7/evolution12/evolutionclues.html
The bones in the diagrams below
Homologous
are examples of____________
structures
1.A.4.b.2. Morphological homologies represent features shared by common ancestry.
Vestigial structures are remnants of functional structures, which can be compared to fossils and provide evidence for evolution.
Structures that develop from the
same embryonic tissues, but have
different mature forms
Homologous structures
Organs that are historical
remnants of structures that had
important functions in ancestors
Vestigial organs
The adaptations in species of finches
that Darwin observed on the
Galάpagos Islands were
different shaped _____________
beaks
Why did Darwin first hesitate to
publish his ideas about evolution?
His findings challenged
fundamental scientific beliefs at
the time
A possible explanation for a set of
observations or a possible answer
to a scientific question
hypothesis
Change in the DNA sequence of an
organism due to mistakes in
replication or damage from
radiation or chemicals
mutation
Who is the scientist that proposed
the idea that forces which have been
changing the Earth are still at work?
Charles Lyell
Who realized that human populations
were increasing and said eventually
there would not be enough food and
space for everyone?
Thomas Malthus
Whales and wolves share a common
ancestor, but have evolved to look
very different. This is an example
of _____________
evolution.
divergent
What do we call genes that have
lost their function due to mutations?
pseudogenes
Tell one piece of evidence that
suggests human chromosome #2
evolved by joining 2 smaller
ancestor chromosomes.
Banding pattern matches
It has telomeres in the middle
instead of just at the ends.
It has an extra inactive centromere
instead of just one.
CREATE A
CLADOGRAM
FROM THIS
DATA TABLE
LANCET
LAMPREY
TUNA
SALAMANDER
TURTLE
LEOPARD
HAIR
AMNIOTIC
TETRAPOD
JAWS
BACKBONE
Essential Knowledge: 1.B.2: Phylogenetic trees and cladograms are graphical representations (models) of evolutionary history that can be tested.
SP 1: The student can create representations and models of natural or man-made phenomena and systems in the domain.
LO 1.19: The student is able create a phylogenetic tree or simple cladogram that correctly represents evolutionary history and speciation from a provided data
set.
Give an example of homologous
structures
Human arm, bird wing, whale flipper
Give an example of a pseudogene you
learned about
Vitamin C gene in primates,
genes for “smell” in humans
Who is the scientist that proposed
an idea about evolution which
prompted Darwin to publish his theory?
Alfred Russell Wallace
When lions prey on a herd of antelope,
some antelope are killed and some
escape. Which part of Darwin’s theory of
evolution might be used to describe this
situation? Survival of the fittest;
natural selection
Explain what was incorrect about Lamarck’s
Inheritance of Acquired Traits
hypothesis
TRAITS ARE DETERMINED BY GENES;
ACQUIRED TRAITS ARE NOT PASSED ON
Explain what was correct about Lamarck’s
Inheritance of Acquired Traits
hypothesis
LIVING THINGS CHANGE OVER TIME TO
BEST FIT THEIR ENVIRONMENTS
Another name for divergent evolution
Adaptive radiation
is ________________
What Darwin called “survival of the
fittest”
Natural selection
_________________
Another name for “struggle for
competition
existence” is _______________
Darwin’s concept of evolution was influenced by all
of the following EXCEPT
A. Charles Lyell’s and James Hutton’s work which
said there are forces shaping the Earth’s surface
that have been happening for millions of years and
are still happening
B. specimens and fossils he collected
C. his knowledge of the structure of DNA
D. his voyage around the world
E. Malthus’s ideas about how shortages of resources
can negatively impact populations
C. Darwin didn’t know about DNA!
Whales and sharks are not closely
related, but have evolved to have
similar body shapes and fins
because they live in similar
environments. This is an example of
_____________
evolution.
convergent
TELL THE CONDITIONS UNDER
WHICH THE HARDY-WEINBERG
PRINCIPLE HOLDS TRUE:
LARGE population
Random mating
TED talksFive fingers of Evolution
NO mutations
NO movement IN OR OUT
NO natural selection
1.A.1.g. Conditions for a population or an allele to be in Hardy-Weinberg equilibrium are: (1) a large population size, (2) absence of migration, (3) no
net mutations, (4) random mating and (5) absence of selection. These conditions are seldom met.
All of these statements about the structure of
human chromosome #2 provide evidence for
evolution EXCEPT
A. Its banding pattern matches the pattern seen on two smaller
chimp chromosomes
B. It has telomeres in the center, as well as at the ends
C. It carries a functional gene for making vitamin C
D. It has an extra non-functional centromere
C. Humans have a nonfunctional vitamin C making gene,
and its not on chromosome #2
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006
Name the type of selection
shown in the diagram below.
Directional selection
1.A.4.b.2. Morphological homologies represent features shared by common ancestry.
Vestigial structures are remnants of functional structures, which can be compared to fossils and provide evidence for evolution
Traits controlled by two or more
genes
Polygenic trait
Process by which related organisms
evolve differences when they are
isolated in different environments
Divergent evolution OR
Adaptive radiation
Measuring lima beans and finding
beans come in different sizes is an
example of ____________
Natural variation
Process by which unrelated
organisms independently evolve
similarities when adapting to
similar environments or to solve
similar problems
Convergent evolution
Stabilizing selection, individuals
In _____________
near the center of a normal curve of
distribution have higher fitness than
those at the extremes
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006
1.A.4.b.2. Morphological homologies represent features shared by common ancestry.
Vestigial structures are remnants of functional structures, which can be compared to fossils and provide evidence for evolution
Changes in the allele frequency
in a small population that are due
to random chance and don’t follow
the laws of probability
Genetic drift
Essential Knowledge 1.A.1.f. In addition to natural selection, chance and random events can influence the evolutionary process, especially for small
populations.
A change in a DNA sequence caused
by a mistake in DNA replication or
exposure to radiation or chemicals
mutation
7
4
1
8
2
5
3
6
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various
pre-and post-zygotic mechanisms can maintain reproductive isolation and prevent gene flow.
All the genes, including all the
different alleles, in a
population
Gene pool
A situation in which the allele
frequencies in a population do NOT
change and the population does
NOT EVOLVE
Genetic equilibrium
http://www.dwm.ks.edu.tw/bio/activelearner/19/ch19summary.htm
lhttp://newhaven828.typepad.com/.a/6a00d8347ae50569e200e5538e3c2e8834-320
The copulatory organs of two
insect species do not fit
together. This is an example of a
pre zygotic reproductive
_____
barrier called ______________
mechanical
isolation
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic
mechanisms can maintain reproductive isolation and prevent gene flow.
Tell the 2 equations needed to
solve Hardy Weinberg problems
p + q = 1
P2 + 2pq + q2 = 1
The number of times a certain
allele occurs in a gene pool
compared to the number of times
other alleles for the same gene occur
Relative frequency
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Application of the Hardy-Weinberg equilibrium equation
4.C.3. c. Allelic variation within a population can be modeled by the Hardy- Weinberg equation(s).
FROM:
http://serranohighschoolapbiology.weebly.com/uploads/6/7/9/9/6799747/ap_biology_evolution_unit_practice_test_1.pdf
Males of different species of the fruit fly Drosophila that
live in the same parts of the Hawaiian Islands have different
elaborate courtship rituals. These rituals involve fighting
other males and making stylized movements that attract
females. What type of reproductive isolation does this
represent?
A) habitat isolation
B) temporal isolation
C) behavioral isolation
D) gametic isolation
E) postzygotic barriers
. Essential knowledge
1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain
range, or various pre-and post-zygotic mechanisms can maintain reproductive isolation and prevent gene flow.
Tell two sources of genetic variation
in populations
Mutations
caused by mistakes in copying DNA
caused by radiation
or environmental chemicals
Gene shuffling during meiosis
crossing over
independent assortment
Essential Knowledge 1.A.2. b. Phenotypic variations are not directed by the environment but occur through random changes in the DNA and through new gene
combinations.
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006
In ___________
disruptive
selection,
individuals at the extreme ends
of the normal distribution curve
have higher fitness than those
near the center of the curve
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Graphical analysis of allele frequencies in a population
In a population of squirrels, the allele that
causes bushy tail (B) is dominant, while the
allele that causes bald tail (b) is recessive.
If 64% of the squirrels have a bushy tail,
what is the frequency of the dominant allele?
q2
= 1.0 - 0.64 = 0.36
q = √0.36 = 0.6
p + q = 1
q2 + 2pq +p2 = 1
p = 1.0 – 0.6 = 0.4
A = 40%
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Application of the Hardy-Weinberg equilibrium equation
4.C.3. c. Allelic variation within a population can be modeled by the Hardy- Weinberg equation(s).
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006
Name the type of selection
shown in the diagram below.
Stabilizing selection
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Graphical analysis of allele frequencies in a population
WHICH PATTERN of SELECTION IS IT?
stabilizing
disruptive
directional
Lighter colored peppered moths were more
common in England prior to the Industrial
revolution. As pollution increased, the darker
colored moths were less likely to be eaten. Over
time darker colored moths have become more
abundant in the population.
directional selection
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006
directional selection
In ___________
individuals at one end of the
normal distribution curve have
higher fitness than individuals in
the middle or at the other end
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Graphical analysis of allele frequencies in a population
If all the conditions of HardyWeinberg are met, what happens
to the population?
There is NO EVOLUTION
Which variable is used to represent
the frequency of the
RECESSIVE PHENOTYPE in a
population in a Hardy Weinberg
problem?
q2
Can all the conditions of
Hardy-Weinberg ever be met?
MOST OF THE TIME NO WAY!
You can have small & isolated populations
(no moving in or out) BUT. . . there is
always non-random mating, mutations, &
natural selection. So there is ALMOST
ALWAYS EVOLUTION HAPPENING !
FROM:
http://serranohighschoolapbiology.weebly.com/uploads/6/7/9/9/6799747/ap_biology_evolution_unit_practice_test_1.pdf
Over evolutionary time, many cave–dwelling organisms have
lost their eyes. Tapeworms have lost their digestive systems.
Whales have lost their hind limbs. How can natural selection
account for these losses?
A) Natural selection cannot account for losses, only for
innovations.
B) Natural selection accounts for these losses by the
principle of use and disuse.
C) Under particular circumstances that persisted for long
periods, each of these structures presented greater
costs than benefits.
D) The ancestors of these organisms experienced harmful
mutations that forced them to find new habitats that
these species had not previously used
Essential knowledge 1.A.2: Natural selection acts on phenotypic variations in populations.
a. Environments change and act as selective mechanism on populations.
LO 1.5 The student is able to connect evolutionary changes in a population over time to a change in the environment.
FROM:
http://serranohighschoolapbiology.weebly.com/uploads/6/7/9/9/6799747/ap_biology_evolution_unit_practice_test_1.pdf
Certain proteins of the complex motor that drives bacterial flagella are
modified versions of proteins that had previously belonged to plasma
membrane pumps. This evidence supports the claim that
A) some structures are so complex that natural selection
cannot, and will not, explain their origins.
B) the power of natural selection allows it to act in an almost predictive
fashion, producing organs that will be needed in future environments.
C) the motors of bacterial flagella were originally synthesized abiotically.
D) natural selection can produce new structures by coupling together
parts of other structures.
E) bacteria that possess flagella must have lost the ability to pump certain
chemicals across their plasma membranes.
.
Essential
knowledge 1.B.1:
Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today.
a. Structural and functional evidence supports the relatedness of all domains.
Darwin believed in the idea that
evolution happened slowly over a
long period of time called
__________
gradualism
Pattern of evolution in which long
stable periods of little evolution
interrupted by brief periods of
rapid change
Punctuated equilibrium
The clan of “blue people” in Kentucky you
learned about are descended from an
immigrant who carried the allele for a
mutant form of hemoglobin and settled in
the area which has little contact with
the outside. This is an example a kind of
genetic drift called _________
founder effect
A change in relative frequency
of alleles in a population
evolution
WHICH PATTERN IS IT?
coevolution
adaptive radiation
punctuated equilibrium
divergent evolution
mass extinction
Horse evolution shows long stable periods
of little evolution interrupted by brief
periods of rapid change
Punctuated equilibrium
Biology by Miller and Levine Pearson Publishing
WHICH PATTERN IS IT?
coevolution
adaptive radiation
punctuated equilibrium
divergent evolution
mass extinction
At the end of the Cretaceous period an asteroid
hit the Earth causing the loss of many species
including the dinosaurs
Mass extinction
http://www.biologycorner.com/worksheets/hardy_weinberg_problemset_key.html
IN DRAGONS Wings = dominant; No wings = recessive
Calculate the allele and phenotypic frequencies
for this population.
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Application of the Hardy-Weinberg equilibrium equation
4.C.3. c. Allelic variation within a population can be modeled by the Hardy- Weinberg equation(s).
7/21= 0.33
q2 = _______
q = ____
0.57
p = ____
0.43
0.18
P2 = ____
2pq = _____
0.49
43%
A = _____
57%
a = _____
49% aa= ____
18% Aa = ____
33%
AA = ____
Iamge from:
file:///C:/Users/riedellke/Google%20Drive/FileBlimp/AP%20BIO/AP%20BIO%20Evolution/EXAMS/ap_biology_evolution_unit_practice_test_1.pdf
Based on this tree, which two organisms are
the most closely related?
Goats and humans are more closely related
because they share a more recent common ancestor
Essential knowledge 1.B.2: Phylogenetic trees and cladograms are graphical representations (models) of evolutionary history that can be tested.
b. Phylogenetic trees and cladograms illustrate speciation that has occurred, in that relatedness of any two groups on the tree is shown by
how recently two groups had a common ancestor.
http://images.encarta.msn.com/xrefmedia/aencmed/targets/illus/ilt/T014608A.gif
WHICH PATTERN IS IT?
coevolution
adaptive radiation
punctuated equilibrium
divergent evolution
mass extinction
The Galápagos finches evolved through natural
selection from a common ancestor into a wide
variety of different looking species with different
kinds of beaks
Adaptive radiation (divergent evolution)
Five new species of bacteria were discovered in Antarctic ice core
samples. The nucleotide (base) sequences of rRNA subunits were
determined for the new species. The table below shows the number of
nucleotide differences between the species.
Which of the following
phylogenetic trees is most
consistent with the
data?
Sample MC questions from
2015 Course and Exam
Description Book posted on
College Board website
Essential Knowledge: 1.B.2: Phylogenetic trees and cladograms are graphical representations (models) of evolutionary history that can be tested.
SP 1: The student can create representations and models of natural or man-made phenomena and systems in the domain.
LO 1.19: The student is able create a phylogenetic tree or simple cladogram that correctly represents evolutionary history and speciation from a provided data
set.
WHICH PATTERN IS IT?
coevolution
adaptive radiation
punctuated equilibrium
divergent evolution
mass extinction
Hummingbirds have a beak just the right length
to reach the nectar in a cardinal flower and as
they feed their foreheads bump into the pollen
structure. Cardinal flowers are red which
hummingbirds can see, but bees can’t, and their
pollen structure is at just the right height for
the hummingbird to pick up pollen as it feeds.
coevolution
WHICH PATTERN IS IT?
coevolution
adaptive radiation
punctuated equilibrium
divergent evolution
mass extinction
Whales, sharks, and penguins all have streamlined
bodies and fins/flipper for moving in water
even though they belong in different animal groups
(mammals, fish, and birds)
Convergent evolution
WHICH PATTERN IS IT?
coevolution
adaptive radiation
punctuated equilibrium
divergent evolution
mass extinction
Beaver
Beaver
NORTH
AMERICA
Muskrat
Muskrat
Beaver
and
Muskrat
Capybara
SOUTH AMERICA
Coypu
Coypu
Beaver in North America
and capybara in South
America are closely
related species living in
very different
environments that have
evolved to look different
over time.
Adaptive radiation OR divergent evolution
BIOLOGY by Miller and Levine Pearson Publishing
A group of students summarized
information on five great extinction
events. The students are sampling a
site in search of fossils from the
Devonian period. Based on the chart,
which of the following would be
the most reasonable plan for the
students to follow?
(A) Searching horizontal rock layers in any class of rock and trying to find those
that contain the greatest number of fossils.
(B) Collecting fossils from rock layers deposited prior to the Permian period that
contain some early vertebrate bones.
(C) Looking in sedimentary layers next to bodies of water in order
to find marine fossils of bivalves and trilobites.
(D) Using relative dating techniques to determine the geological ages of the
fossils found so they can calculate the rate of speciation of early organisms
Sample MC questions from
2015 Course and Exam Description Book
posted on College board website
Essential Knowledge 1.C.1: Speciation and extinction have occurred throughout the Earth's history.
SP 4.2: The student can design a plan for collecting data to answer a particular scientific question.
LO 1.21: The student is able to design a plan for collecting data to investigate the scientific claim that speciation and extinction have occurred throughout
Earth’s history.
WHICH PATTERN IS IT?
coevolution
adaptive radiation
punctuated equilibrium
divergent evolution
mass extinction
The tortoises on the Galapagos islands share a
common ancestor, but over time they have become
adapted for obtaining food in different habitats
on different islands by having different
neck lengths
Adaptive radiation OR
divergent evolution
FROM:
http://serranohighschoolapbiology.weebly.com/uploads/6/7/9/9/6799747/ap_biology_evolution_unit_practice_test_1.pdf
The rise of methicillin–resistant Staphylococcus aureus (MRSA) can be
considered to be an example of artificial selection because
A) humans purposefully raise MRSA in large fermenters in an attempt to
make the bacteria ever–more resistant.
B) S. aureus is cultivated by humans to replenish the soil with nutrients.
C) humans synthesize methicillin and create environments in which
bacteria frequently come into contact with methicillin.
D) Humans are becoming resistant to bacteria by taking methicillin
Essential knowledge 1.A.2: Natural selection acts on phenotypic variations in populations.
d. Humans impact variation in other species.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Artificial selection
• Overuse of antibiotics
LO 1.5 The student is able to connect evolutionary changes in a population over time to a change in the environment.[See SP 7.1]
Similarities that result from
CONVERGENT evolution are
considered to be ____________
analogous
structures.
homologous
analogous
WHICH PATTERN of SELECTION IS IT?
stabilizing
disruptive
directional
Human babies born smaller than average are likely
to be less healthy and less likely to survive.
Larger than average babies are likely to have
difficulty being born. The fitness of these larger
or smaller weight babies is lower than averagesized babies so human babies tend to born of
average size.
Stabilizing selection
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Graphical analysis of allele frequencies in a population
Image from BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006
Name the type of selection
shown in the diagram below.
Disruptive selection
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Graphical analysis of allele frequencies in a population
WHICH PATTERN of SELECTION IS IT?
stabilizing
disruptive
directional
A population of birds lives in an area where plants
with medium sized seeds are wiped out by a
fungal infection. Birds with unusually large or
small beaks would have higher fitness than those
with medium sized beaks. Over time the
population splits into two subgroups; one that eats
small seeds and one that eats large seeds.
disruptive selection
http://www.dwm.ks.edu.tw/bio/activelearner/19/ch19summary.html
Mules produced when a horse and
donkey interbreed are sterile. This
is an example of a
_____
post zygotic reproductive barrier
called hybrid ____________
infertility
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic
mechanisms can maintain reproductive isolation and prevent gene flow.
All of the following influenced
Darwin except
Lyell
Mendel
Hutton
Malthus
Lamarck
Mendel
Which variable is used to represent
the frequency of the recessive
allele in a Hardy Weinberg
problem?
q
http://sisu.typepad.com/sisu/spongebob.jpg
Sperm of one sponge species cannot
penetrate the egg of a closely
related species.This is an example
pre zygotic reproductive
of a _____
barrier called _________
isolation
gametic
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic
mechanisms can maintain reproductive isolation and prevent gene flow.
In the formula for determining a population's
genotype frequencies, the 2 in the term 2pq
is necessary because
A) the population is diploid.
B) heterozygotes can come about in two
ways.
C) the population is doubling in number.
D) heterozygotes have two alleles
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Application of the Hardy-Weinberg equilibrium equation
4.C.3. c. Allelic variation within a population can be modeled by the Hardy- Weinberg equation(s).
Evolutionary change above the species level
including the appearance of major
evolutionary developments like flight
(EX: fish → amphibians) is called
macro
_________evolution
Which variable is used to represent the
frequency of the dominant PHENOTYPE in
a population in a Hardy Weinberg
problem?
p2
In a hypothetical population of beetles, there is a wide variety of color, matching the range of
coloration of the tree trunks on which the beetles hide from predators. The graphs below
illustrate four possible changes to the beetle population as a result of a change in the
environment due to pollution that darkened the tree trunks.
Which of the following includes the
most likely change in the coloration of
the beetle population after pollution and
a correct rationale for the change?
(A) The coloration range shifted toward more light-colored beetles (diagram I).
The pollution helped the predators find the darkened tree trunks.
(B) The coloration in the population split into two extremes (diagram II)
Both the lighter-colored & darker-colored beetles were able to hide on the darker
tree trunks.
(C) The coloration range became narrower (diagram III)
The predators selected beetles at the color extremes.
(D) The coloration in the population shifted toward more darker- colored beetles (diagram 1V)
The lighter-colored beetles were found more easily by
the predators than were the darker-colored beetles. Sample MC questions from
2015 Course and Exam Description Book
posted on College Board website
Essential Knowledge 1.A.4: Biological evolution is supported by scientific evidence fro mmany disciplines, including mathematics.
SP 1.1: The student can create representations and models of natural or man-made phenomena and systems in the domain.
Lo 1.13: The student is able to construct and/or justify mathematical models, diagrams, or simulations that represent processes of biological evolution.
Which variable(s) is/are used to
represent the frequency of the
HETEROZYGOUS PHENOTYPE in a
population in a Hardy Weinberg
problem?
2pq
1.A.1.h. Mathematical approaches are used to calculate changes in allele frequency, providing evidence for the occurrence of evolution in a population.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Application of the Hardy-Weinberg equilibrium equation
4.C.3. c. Allelic variation within a population can be modeled by the Hardy- Weinberg equation(s).
Mode of speciation induced when an
ancestral population becomes split
by a geographic barrier
Allopatric “other country”
WHAT’s the DIFFERENCE BETWEEN:
Gene Flow and Genetic Drift?
GENETIC DRIFT
Changes in gene
pool NOT related
to natural selection
vs
Due to random chance
Start a new population
•
Founder effect
•
Bottlenecks
http://larryfrolich.com/Evolution/NaturalSelection/founder.jpg
http://biology.gsu.edu/houghton/2107%20'08/Figures/Chapter22/bottleneck.jpg
GENE FLOW
Migration of
alleles or genes
from one
population
to another.
http://www.umbc.edu/bioclass/biol100/powerpoints/lecture10/img03
4.jpg
FROM: http://serranohighschoolapbiology.weebly.com/uploads/6/7/9/9/6799747/ap_biology_evolution_unit_practice_test_1.pdf
All animals with eyes or eyespots that have been studied so far share a gene in
common. When mutated, the gene Pax-6 causes lack of eyes in fruit flies, tiny eyes
in mice, and missing irises (and other eye parts) in humans. The sequence of Pax-6
in humans and mice is identical. There are so few sequence differences with fruit
fly Pax-6 that the human/mouse version can cause eye formation in eyeless fruit
flies, even though vertebrates and invertebrates last shared a common ancestor
more than 500 million years ago. The appearance of Pax–6 in all animals with eyes
can be explained in multiple ways. Based on the information above, which
explanation is most likely?
A) Pax–6 in all of these animals is not homologous; it arose independently in many
different animal phyla due to intense selective pressure favoring vision.
B) The Pax–6 gene is really not "one" gene. It is many different genes that, over
evolutionary time and due to convergence, have come to have a similar
nucleotide sequence and function.
C) The Pax–6 gene was an innovation of an ancestral animal of the early Cambrian
period. Animals with eyes or eyespots are descendants of this ancestor.
D) The perfectly designed Pax–6 gene appeared instantaneously in all animals
created to have eyes or eyespots.
Essential Knowledge 1.B.1: Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today.
SP 7.2: The student can connect concepts in and across domain(s) to generalize or extrapolate in and/or across enduring understandings and/or big ideas.
LO 1.15: The student is able to describe specific examples of conserved core biological processes and features shared by all domains or within
one domain of life, and how these shared, conserved core processes and features support the concept of common ancestry for all organisms.
FROM: http://serranohighschoolapbiology.weebly.com/uploads/6/7/9/9/6799747/ap_biology_evolution_unit_practice_test_1.pdf
Fruit fly eyes are of the compound type, which is structurally very
different from the camera–type eyes of mammals. Even the camera–type
eyes of molluscs, such as octopi, are structurally quite different from
those of mammals. Yet, fruit flies, octopi, and mammals possess very
similar versions of Pax–6. The fact that the same gene helps produce very
different types of eyes is most likely due to
A) the few differences in nucleotide sequence among the Pax–6 genes
of these organisms.
B) variations in the number of Pax–6 genes among these organisms.
C) the independent evolution of this gene at many different times
during animal evolution.
D) differences in the control of Pax–6 expression among these
organisms
Essential Knowledge 1.B.1: Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today.
SP 7.2: The student can connect concepts in and across domain(s) to generalize or extrapolate in and/or across enduring understandings and/or big ideas.
LO 1.15: The student is able to describe specific examples of conserved core biological processes and features shared by all domains or within
one domain of life, and how these shared, conserved core processes and features support the concept of common ancestry for all organisms.
FROM: http://serranohighschoolapbiology.weebly.com/uploads/6/7/9/9/6799747/ap_biology_evolution_unit_practice_test_1.pdf
Pax–6 usually causes the production of a type of light–receptor pigment.
In vertebrate eyes, though, a different gene (the rh gene family) is
responsible for the light–receptor pigments of the retina. The rh gene,
like Pax–6, is ancient. In the marine ragworm, for example, the rh gene
causes production of c–opsin, which helps regulate the worm's biological
clock. Which of these most likely accounts for vertebrate vision?
A) The Pax–6 gene mutated to become the rh gene among early mammals.
B) During vertebrate evolution, the rh gene for biological clock opsin was
co–opted as a gene for visual receptor pigments.
C) In animals more ancient than ragworms, the rh gene(s) coded for visual
receptor pigments; in lineages more recent than ragworms, rh has flip–
flopped several times between producing biological clock opsins and
visual receptor pigments.
D) Pax–6 was lost from the mammalian genome, and replaced by the rh
gene much later.
Essential Knowledge 1.B.1: Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today.
SP 7.2: The student can connect concepts in and across domain(s) to generalize or extrapolate in and/or across enduring understandings and/or big ideas.
LO 1.15: The student is able to describe specific examples of conserved core biological processes and features shared by all domains or within
one domain of life, and how these shared, conserved core processes and features support the concept of common ancestry for all organisms.
Mode of speciation occurring as a
result of a radical change in the
genome of a subpopulation
reproductively isolating it from the
parent population (EX: polyploidy)
sympatric “same country”
The geographic distribution patterns
of species that support Darwin’s
theory
biogeography
http://ipm.ncsu.edu/cotton/InsectCorner/photos/images/Open_cotton_plant.jpg
Two cotton species produce fertile
hybrids but the next generation is
infertile. This is an example of a
post zygotic reproductive
_____
barrier called hybrid __________
breakdown
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic
mechanisms can maintain reproductive isolation and prevent gene flow.
Gene flow occurs when a
__________
population gains or loses alleles
when individuals move in or out of
a population
Kind of genetic drift in which a
sudden change in the environment
(ex: earthquake, tidal wave, fire)
drastically reduces the size of
population Bottleneck effect
Experimental evidence shows that the process of glycolysis is present
and virtually identical in organisms from all three domains, Archaea,
Bacteria, and Eukarya. Which of the following hypotheses could be
best supported by this evidence?
(A) All organisms carry out glycolysis in mitochondria.
(B) Glycolysis is a universal energy-releasing process and therefore
suggests a common ancestor for all forms of life.
(C) Across the three domains, all organisms depend solely on the
process of anaerobic respiration for ATP production.
(D) The presence of glycolysis as an energy-releasing process in all
organisms suggests that convergent evolution occurred.
Sample MC questions from
2015 Course and Exam Description Book
posted on College board website
Essential Knowledge 1.B.1: Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today.
SP 7.2: The student can connect concepts in and across domain(s) to generalize or extrapolate in and/or across enduring understandings and/or big ideas.
LO 1.15: The student is able to describe specific examples of conserved core biological processes and features shared by all domains or within
one domain of life, and how these shared, conserved core processes and features support the concept of common ancestry for all organisms.
The increased chance of survival of
individuals that are heterozygous for
the sickle cell allele helps to maintain
this deleterious recessive allele in
populations that live in areas infected
by malaria. This is called
Heterozygote advantage
Kind of genetic drift in which a population is
drastically reduced in size often due to
environmental disaster, the hunting of a species
to the point of extinction, or habitat destruction
which results in a new population with little
genetic diversity Bottleneck effect
Kind of genetic drift in which a few individuals
become isolated from a larger population and
establish a new population whose gene pool is
different from the parent population
Founder effect
Essential Knowledge 1.A.1.f. In addition to natural selection, chance and random events can influence the evolutionary process, especially for small populations
Essential Knowledge 1.A.1. g. Conditions for a population or an allele to be in Hardy-Weinberg equilibrium are: (1) a large population size, (2) absence of
migration, (3) no net mutations, (4) random mating and (5) absence of selection. These conditions are seldom met.
Idea that allele frequency will
remain constant unless one or more
factors cause those frequencies
to change
Hardy-Weinberg Principle
Essential Knowledge 1.A.1.f. In addition to natural selection, chance and random events can influence the evolutionary process, especially for small populations
Essential Knowledge 1.A.1. g. Conditions for a population or an allele to be in Hardy-Weinberg equilibrium are: (1) a large population size, (2) absence of
migration, (3) no net mutations, (4) random mating and (5) absence of selection. These conditions are seldom met.
http://www.dwm.ks.edu.tw/bio/activelearner/19/ch19summary.htm
l http://www.animationlibrary.com
Nearly all the embryos die when
eggs of a bullfrog are fertilized
artificially with sperm from a
leopard frog. This is an example of
a ____
post zygotic reproductive barrier
pre post
inviability
called hybrid __________
Essential knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
a. Speciation results in diversity of life forms. Species can be physically separated by a geographic barrier such as an ocean or a mountain range, or various pre-and post-zygotic
mechanisms can maintain reproductive isolation and prevent gene flow.
Populations of a plant species have been found growing in the
mountains at altitudes above 2,500 meters. Populations of a plant that
appears similar, with slight differences, have been found in the same
mountains at altitudes below 2,300 meters.
Describe TWO kinds of data that could be collected to provide
a direct answer to the question, do the populations growing
above 2,500 meters and the populations growing below 2,300
meters represent a single species?
Explain how the data you suggested in part (a) would provide a
direct answer to the question.
Sample short answer question from
2015 Course and Exam Description Book
posted on College board website
Essential Knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
SP 4.1: The student can justify the selection of the kind of data needed to answer a particular scientific question.
LO 1.23: The student is able to justify the selection of data that address questions related to reproductive isolation and speciation.
Sample short answer from 2015 Course and Exam Description Book
posted on College board website
http://apcentral.collegeboard.com/apc/members/exam/exam_information/219291.html
Description of the appropriate kind of data and the appropriately linked
explanation of its selection may include:
Essential Knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
SP 4.1: The student can justify the selection of the kind of data needed to answer a particular scientific question.
LO 1.23: The student is able to justify the selection of data that address questions related to reproductive isolation and speciation.
Examination of chimp and human karyotypes shows that chimps have
2 smaller chromosome pairs not found in humans; and humans have one
larger chromosome pair (#2) not found in chimps.
It has been suggested that human chromosome # 2 was formed by the
end-to-end fusion of the two chimp chromosomes at some point in the
past. If this is true, there should be some evidence that can be observed
to support this idea.
Use what you know about the STRUCTURE OF EUKARYOTIC
CHROMOSOMES to MAKE THREE (3) PREDICTIONS about the
structure of human chromosome #2 that would suggest
“relatedness” between these chromosomes.
COLOR OR ADD LABELS TO THIS DIAGRAM.
“If this fusion explanation is true, then I would expect that . . . “
Essential Knowledge 1.C.2: Speciation may occur when two populations become reproductively isolated from each other.
SP 4.1: The student can justify the selection of the kind of data needed to answer a particular scientific question.
LO 1.23: The student is able to justify the selection of data that address questions related to reproductive isolation and speciation.
“If this fusion explanation is true, then I would expect that . . . “
1. BANDING PATTERNS of human chromosome #2 and chimp
chromosomes should match up. (They do!)
2. DNA SEQUENCING- DNA/Genes for particular proteins/traits are
in corresponding positions on the chimp/human chromosomes.
(They are!)
3. TELOMERES- Eukaryotic chromosomes have telomeres on the tips
to protect code from being lost during replication. If two chimp
chromosomes fused, then there should be telomere sequences in
the middle of human chromosome #2 where the fusion occurred.
(There is)
4. If telomeres in middle of #2 come from fusion, then other human
chromosomes that weren’t fused should NOT have telomeres in middle.
(There don’t; #2 is only human chromosome with telomere sequences in
middle)
5. CENTROMERES- Eukaryotic chromosomes have centromere regions to
which spindle fibers attach during cell division. If two chimp
chromosomes fused, then there should be 2 centromere regions on human
chromosome #2. (There are; one is inactive!)
THE END. . . or is it?
EVOLUTION IS STILL HAPPENING
See a video