Download 1) UNIT 5 MechanismsOfEvolution

UNIT 5: Mechanisms of Evolution
Vocabulary terms:
populations, species, evolution, natural selection, change, favorable traits, variation, adaptations,
directional selection, disruptive selection, stabilizing selection, natural selection, genetic variation,
survive, limited resources, competition, over-population, carrying capacity, genetic drift, gene flow,
mutation, recombination, differential reproductive success, diversity, gene pool, subspecies, geographic
isolation, Founder Effect, gene frequency, mimicry, speciation, genetic kinship, selective pressure,
random mating, homologous structures, analogous structures, co-evolution, divergent evolution,
convergent evolution, Hardy-Weinberg
UNIT 5 Checklist
Notes/Activity/Lab
Proof of
Completion/Teacher
Initials
Prove it!
Part A: Notes Over PPT
in netschool
-Notes Completed
-Word Web Completed
Quiz in Netschool
Part B: Speciation
-Galapagos Speciation
Worksheet
Quiz in Netschool
Part C: Natural
Selection
-Peppered Moth
Simulation Questions
-Pesky Mosquitoes
Worksheet
-Goldfish Lab
-Bird Beak Lab
Part D: Coevolution
-Questions and
Examples
Part E: Gene Flow,
Genetic Drift
-Table filled out
-Questions answered
Part F: Hardy-Weinberg
-Table complete
-H-W Bean Lab
Part G: Endosymbiotic
Theory
-Questions answered
-Sentences completed
Part H: Misconceptions
-12 filled out
Quiz in Netschool
Part A: Notes
Use the Powerpoint on Netschool and notes guide below to complete the notes
Diversity of Life
What does biological diversity mean?__________________________________
________________________________________________________________
Evolution is simply ________________________________________________.
_________________________ contributed more to our understanding of evolution than anyone
else!
Charles Darwin
In Charles Darwin’s time, your parents paid for your college and they only people that got to go
to college were those with money. If your parents paid for college, they decided what you
would study in college. Charles Darwin’s dad told him he would go to college and study
religion…..not what Charles wanted to study. So, when he finished college, at the age of 22, he
set off on a journey that would change his life and the way we think of ourselves. He took a job
as a ________________ on a voyage on the _________________________.
Darwin’s Trip
Wherever the ship anchored, Darwin went ashore to collect plant and animal specimens and
fossils, preserved remains of ancient organisms. Anything he could take back on the ship, he
did. What place influenced Darwin the
most?______________________________________________________
Darwin’s Observations
What did Darwin notice about the Giant Land Tortoise’s?
What did Darwin notice about the Finches?
Darwin’s Influences
What two geologists helped Darwin realize that the Earth was actually really old?
__________________________________________________________________
Who proposed the idea that by selective use or disuse of organs, species acquired or lost certain
traits during their lifetime, and these new traits were passed on to their offspring?
_________________________ Was he correct? ___________
With all of Darwin’s knowledge he wrote a book. What was the name of his book?
__________________________________________
How long did Darwin wait to publish his book? _______________________
Why do you think he waited this long?__________________________________
__________________________________________________________________
Darwin’s Theories on Evolution
Darwin included 4 major points about evolution:
1. Inherited variation exists within the genes of every population or species.
2. In a particular environment, some individuals of a population or species are
_______________________________, to survive and have more offspring. (Natural
selection/survival of the fittest).
Help with survival
________________________ – When an organism blends in with its
surroundings.
__________________ – when an organism copies the appearance of
another species.
3. Over time, the traits that make certain individuals of a population able to
survive
and reproduce tend to spread in that population (descent with modification).
4. There is overwhelming evidence from
_________________________________________________________, similarities in
_______________________________________ that living species evolved from organisms
that are extinct.
Evidence of Evolution
1. Evolution is change over time and is seen in the __________________________.
By dating the sediments around the fossils, paleontologists can arrange the fossils from oldest to
youngest.
2. ___________________________ – structures that are similar in structure but different in
function.
 Example: the forelimbs of vertebrates contain the same kinds of bones, which form the
same way during embryological development, but are used differently when they
mature.
3. ___________________________ – structures that are similar in purpose but different in
structure.
 Example: All of these are used to fly, but are different in structure.
4. ________________________ – the early stages of development are similar in different
organisms
5. ____________________________ – bones or organs that are present in an organism but are
reduced in size and either have no use or have a less important function than they do in other,
related organisms.
 Example: hind limbs of whales.
 Example: human appendix.
6. ______________________(DNA)– most important by far. Similar DNA shows similar
relatedness
4 Main Factors of Natural Selection
1. All populations have __________________________________. Even if you cannot see it, there
is an array of variety in every species.
2. The _____________________________________________ to successful reproduction.
**If an organism does not survive or its offspring die before they can reproduce, their
genes are not passed on to future generations.
3. Individuals tend to _________________________________ than the environment can support.
**Individuals of a population will have to compete with one another.
4. Individuals that are _____________________ with the challenges presented by their
environment tend to leave more offspring than those individuals less suited to the environment.
Gene Pool
 All species have a ___________________which includes all the different alleles for every gene in
that population.
 In the gene pool, a trait controlled by a ___________gene has less genotype and phenotype
possibilities.
 A trait controlled by ___________ gene has many combinations of genotypes and phenotypes, this
means more variety!
Genetic Equilibrium
If a population is left alone and nothing changes with it, the relative frequencies of the alleles in the
gene pool never change.
 Hardy-Weinberg Principle– allele frequencies in a population will remain constant unless one or
more factors cause those frequencies to change.
 However, there are situations that cause these frequencies to change:
 The two main situations are:
 ____________
 ___________________ in gamete formation (crossing over).
 Other sources that cause these frequencies to change are:
 Natural selection towards a particular trait.
 ____________________
 Nonrandom mating.
 _____________________________
Formation of New Species
 A species can evolve to the point of becoming two or more new species. This is known as
__________________.
 The accumulation of differences between groups is called __________________.
 Divergence leads to the formation of new species.
 A second factor that can cause speciation is reproductive ______________ or the loss of the
ability of 2 species to mate and produce viable, fertile offspring.
 _____________________Evolution – when different species become more similar to each other.
Example: shark, penguin, dolphin, all are different species and are becoming better swimmers
and their bodies are becoming more streamline.
3 Types of Natural Selection
1) _________________________ – a type of selection in which genetic diversity decreases as the
population size stabilizes on a particular trait value.
 When individuals near the center of the curve have higher fitness than individuals at
either end of the curve.
 Stabilizing Selection
 Example: Birth weight of babies. If a baby is too small, it tends to get ill quickly.
If a baby is too large, it is very difficult to deliver. A baby of medium size,
however, does not get ill as quickly and is able to be delivered more often
without harming the mother or the baby.
2) _________________________ – a type of selection that simultaneously favors individuals with a
trait that is found at one extreme of the population.
 When individuals at the upper and lower ends of the curve have higher fitness than
individuals near the middle
 Example: Beaks of finches.
 If a beak is very small, the bird can easily pick up small seeds. If a beak is very
large, the bird can easily crack large seeds. If a beak is medium size, however, it
cannot easily pick up seeds, nor can it easily crack large seeds. Thus, these birds
are less adapted to their environment and have lower fitness. In essence, the
trait’s frequencies in a population “disrupt” a normal distribution.
3) __________________________ – a type of selection that favors a single phenotype and
therefore the allele frequency continuously increases.
 When individuals at one end of the curve have higher fitness than individuals in the
middle or at the other end.
 Example: Speed of greyhounds.
 If a dog was slow, owners would not breed them. If a dog was fast, owners
would breed them. Thus, over time, the frequency of fast dogs in the
population increased. In essence, the trait’s frequency in a population moves
“directionally,” from low frequency to high frequency.
Evolutionary Changes
 The speed of evolutionary changes can differ in 2 ways:
1. ______________________ – the idea that evolution occurs gradually over a long period
of time.
2. ________________________ - the idea that evolution occurs with periods of rapid
change which are separated by periods of little or no change.
 _________________ help group organisms based on their evolutionary history and shows the
order in which derived characteristics evolved.
So that means, according to the chart, that Amphibians have _______________________ but not
______________________________.
INTRODUCTION TO EVOLUTION
Go to the following website: http://evolution.berkeley.edu/evosite/evohome.html
Click on the Evolution 101 Tab
1. What is the central idea of biological evolution?
2. What is a phylogeny?
3. Click on the three domains of the tree. Explore.
4.
How do you read a phylogenic tree? Draw and label one.
5. Explain what a clade is? Draw an example of a clade and an example of a non-clade.
THE HISTORY OF EVOLUTION
Go to the following website: http://www.pbs.org/wgbh/evolution/religion/revolution/
You need to focus on the following: focus on Linneaus, Lamark, Lyell, Beagle Voyage, Darwins Secret,
Origin of Species, Wallace, Neanderthal Flint Tools, Ape Debate, Evolution accepted, Mendel, horse
fossils, Man like ape, origins of life, humans and apes, creation science, Lucy, DNA Codes, Intelligent
design, human genome
Take notes over the ones you didn’t already know here:
(Complete the word web below on the next page
Part B: Speciation
Go to the following website: http://evolution.berkeley.edu/evosite/evo101/VSpeciation.shtml
1. How do we define a species?
2. What is a hybrid? How do they blur the definition of a species?
3. What are some of the causes of speciation?
4. Take the Quick Quiz
5. Complete the worksheet in netschool over speciation that occurred in the Galapagos Islands.
Part C: Natural Selection
Go to the following website: http://evolution.berkeley.edu/evolibrary/article/evo_14
Use the tabs to the left to navigate through to answer the questions.
1. Besides natural selection, what are the other types of mechanism of change?
2. What is natural selection?
PEPPERED MOTH ACTIVITY: Human Impact
You will see how human interference can affect natural selection. Go to
http://peppermoths.weebly.com/ and the netschool document “Peppered Moth Simulation”. Complete
the worksheet in your lab notebook.
PESKY MOSQUITOES: Human Impact
Complete the Pesky Moquitoes worksheet (found in Netschool) in your lab notebook.
NATURAL SELECTION: Goldfish Lab
Complete the Goldfish Lab (found in Netschool) in your lab notebook.
BIRD BEAK LAB: Competition
Complete the Bird Beak Lab (found in Netschool) in your lab notebook.
Part D: Co-evolution
Go to the website: http://evolution.berkeley.edu/evolibrary/article/evo_33
1. What is coevolution?
2. Why does coevolution arise?
3. Give two examples of co-evolution and explain how they both evolved.
Here are two examples of co-evolution in the wild:
Killer Fungus https://www.youtube.com/watch?v=RuopJYLBvrI
Host-Virus https://www.youtube.com/watch?v=KBQKz2_ejUA
Part E: Gene Flow and Genetic Drift
Research the difference between gene flow and genetic drift: http://www.shmoop.com/mechanismsevolution/gene-flow-drift.html then, Compare and Contrast.
Gene Flow
Both
Genetic Drift
For the following statements, determine if the statement involves genetic drift, gene flow, or both.
1.
2.
3.
4.
5.
6.
7.
8.
Allele frequency change
A natural disaster wipes out 50% of the population
Allele frequency change within one population
Allele frequency change between two populations
A mountain lion travels to another pride, bringing with it a bushy mane gene
Cheetahs bottleneck, decreasing their frequencies from 75% to almost 1%
Birds from the mainland migrate to different islands of the Galapagos chain
Includes the founder effect and the bottleneck effect
2. Below are two pictures, one is the bottleneck effect and the other is the founder effect.
Which one is which? WHY?
A
B
Part F: Hardy-Weinberg
Go to https://www.youtube.com/watch?v=JsuJlewaPX0
1. What are the five main assumptions in Hardy-Weinberg?
-An allele frequency is talking about how often that allele shows up with a population. For example, with
pigs (A=pink, a=black).
If there are 16 pigs, then there are 32 total alleles (16 pigs with 2 alleles each)
 4 pigs are black (aa)= 8a
 6 pigs are heterozygous (Aa)= 6A and 6a
 6 pigs are pink (AA)= 12 A
Show me how you would come up with the allele frequency for the pig example!
Allele
A= PINK
a= BLACK
Frequency =
total of that allele
total of all alleles
SO THE H-W EQUATION: p2 +2pq +q2 = 1
HARDY-WEINBERG BEAN LAB
Complete the Hardy-Weinberg bean lab in your lab notebook.
Part G: Endosymbiotic Theory
Go to http://www.sumanasinc.com/webcontent/animations/content/organelles.html
1. What similarities are seen between prokaryotes and mitochondria/chloroplasts?
2. What does the endosymbiotic theory propose is the process by which eukaryotes arose?
3. Who is responsible for the Endosymbiotic Theory?
4. How did the other organelles, like endoplasmic reticulum, arise?
Go to the menu, click activity and complete the sentences. Get this checked by me.
Part H: Misconceptions
Go to the following website: http://evolution.berkeley.edu/evosite/misconceps/index.shtml
Go through the misconceptions of evolution. For each one, write down the misconception and then
write down what the correct focus of each one is.
Misconception 1:
What it really is about:
Misconception 2:
What it really is about:
Misconception 3:
What it really is about:
Misconception 4:
What it really is about:
Misconception 5:
What it really is about:
Misconception 6:
What it really is about:
Misconception 7:
What it really is about:
Misconception 8:
What it really is about:
Misconception 9:
What it really is about:
Misconception 10:
What it really is about:
Misconception 11:
What it really is about:
Misconception 12:
What it really is about:
When you get to the “Misconceptions: Implications of Evolution”, you may STOP.