Mutations, Evolution, Fitness & Darwin

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Name:________________________________________________
Per:_________________
Evolution
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Mutations
1. Vocabulary:
a. Mutation: A change in an organisms _________________
b. Point mutation: A mutation that happens when an incorrect nucleotide is
________________ into a DNA molecule
c. Frameshift mutation: The addition or ______________________ of a nucleotide during a
DNA sequence
2. Mutation Information:
Mutation
Personal Word Wall
Mutation
Fitness
Point mutation
Adaptation
Frame mutation
Variation
Mutagen
Darwin
Evolution
Can be good or bad
Mutagen
Creationism
Point mutation
Species
Fossils
Frameshift mutation
Examples:
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3. Why do Mutations matter?
a. Mutations cause _________________ in ________________.
b. Mutations are what cause individuals within a species to have ________________
Name:________________________________
Per:______
Practice #1 – mutations
Teenage Mutant Ninja Turtles are turtles
that can talk, hang out, and fight off bad
guys. They live in the sewers of New
York. Here are each of their mutations:
Leonardo: Martial arts fighter, leader
Donatello: Brilliant scientist and engineer
Raphael: Aggressive nature, intense
fighter
Michelangelo: Funny guy
Questions:
1. Why are they called mutant
turtles?______________________
_____________________________
_____________________________
_____________________________
2. Are their mutations beneficial?
Why or why not?_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
3. Are the Teenage Mutant Ninja Turtles similar to their species or different?
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
Homework #1 – mutations
1. What is the difference between a mutation and a mutagen?
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2. What are the two types of mutations?
3. Explain in your own words what a mutation is:
Evolution Controversy
1. Vocabulary:
a. Evolution: A ________________ in _____________________ over __________________
i. _______________________________________________________________________________________
_______________________________________________________________________________________
b. Creationism: The process by which every _________________ thing was made by a
________________________ power
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2. What do you think this cartoon means?
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
Evolution in Schools?
The creation and evolution controversy, is a
debate over how life was created and which
version of the origins of life should be taught to
children. On one side of the creation and
evolution controversy are the creationists, which
assert that God created all life on Earth as
described in the Bible, and on the other side are the advocates of Darwin's theory of
evolution and natural selection, which asserts that all organisms evolved incrementally
over millions of years.
People are especially concerned about whether evolution should be taught in schools.
One of the most significant historical blowups in the creation and evolution debate was
the Scopes Trial, often called the Scopes Monkey Trial, which was held in 1925 in
Dayton, Tennessee. After World War I, the Fundamentalist-Modernist controversy was
raging in America, a movement which led to the introduction of legislation in 15 states
banning the teaching of evolutionary theory in classrooms.
A biology teacher, John Scopes, flaunted the law by teaching evolution in his classroom,
and was arrested. The ensuing trial became a media circus, attracting international
attention to the case. Scopes was ultimately convicted and fined, but so much
sympathetic media attention was given to his side of the story that many advocates of
evolution considered it to be a minor victory. Still, evolution continued to be omitted from
biology textbooks in some states for many years.
The creation and evolution debate is still as intense today as it was in 1925, though
public opinion has shifted in favor of the teaching of evolution. It remains to be seen how
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the controversy will unfold, but a few quick conversations with members of the opposing
sides shows that the confrontation is far from over.
2. In our classroom

Evolution is ________________ of the High School biology _________________________________

You are entitled to ________________________________ everything and encouraged to
_______________________________ whatever you would like
Main Idea:
Supporting
Detail:
Supporting
Detail:
Supporting
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Detail:
Name:________________________________
Per:______
Practice #2 – Evolution controversy
Evolution Survey
Instructions: Choose whether each statement is true or false, in terms of how you think
biologists use and understand the term evolution today. You do NOT have to agree with the
statement for it to be “true” as you think biologists see it.
1. Evolution is a scientific fact
2. Evolution is something you should either believe in, or not believe in
3. Evolution is a process that involved the origin of life
4. Evolution is primarily concerned with the origin of humans
5. According to evolution, people came from monkeys a long time ago
6. Evolution was first proposed and explained by Charles Darwin
7. Evolution is something that happened in the past and is not happening now
8. Evolution can be compatible with all the world’s major religions
9. Evolution is only a theory
10. There is little evidence for evolution
11. Evolution theory has been tested many times, and has always been supported by the
evidence
12. Evolution is a totally random process, or a series of “accidents”
Homework #2 – Evolution controversy
1. Are there any other issues you can think of that are similar to evolution (they are
controversial)?
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2. Explain what the word “controversial” means in your own words.
What is Evolution?
1. Vocabulary:
a. Evolution: ____________________________________________________________________________________
_________________________________________________________________________________________________
2. What is evolution?
Evolution
3. Key Ideas of evolution
a. Fitness: An organisms ability to produce more ____________________ relative to other
members of its _________________________
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b. Adaptation: Feature that allows organisms to _____________________
______________________________ in their _____________________________________
i. Takes millions of years!
Name:________________________________
Per:______
Practice #3 – What is evolution?
Adaptations:
Directions: Choose the best adaptation
for each of the animals listed below.
 Sharp claws
1. Mole
 Thick fur
 Camouflage
Adaptation:________________________
 Strong beak
2. Wolf
Adaptation:________________________
3. Frog:
Adaptation:________________________
4. Hummingbird:
Adaptation:________________________
Homework #3 – What is evolution?
1. What is evolution?
2. Why do adaptations occur?
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3. How long do adaptations take?
4. What is “fitness”?
5. Why do mutations make
organisms different from
one another?
Fitness
1. Vocabulary:
a. Fitness: Measure of an organisms ability to _____________________ and _____________________
offspring
2. What is it:
a. Within a population, certain individuals are more likely to __________________ and
_________________________. This is called fitness.
b. WHY?
i. Adaptations
1. Examples:
a. Bright colors: ________________________________________________________
b. Long neck: ___________________________________________________________
c. Camouflage: _________________________________________________________
d. Thick fur: _____________________________________________________________
Good ____________
________________
More likely to ______ and ________
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Name:________________________________
Per:______
Practice #4 – Fitness
Directions: Choose which of the following will survive and reproduce (fitness)
1. In a warm environment, dogs that have:
a. Thick fur
b. No fur
c. White fur
2. A frog that rests on dark green leaves:
a. Bright blue skin
b. Rough skin
c. Dark green skin
3. A bird that eats hard-shelled nuts:
a. Strong beak
b. Short beak
c. Brown beak
4. In a snowy area, a wolf that has:
a. Black fur
b. White fur
c. Brown fur
5. In an area where mice are the main food source, a cat that has:
a. A thick tail
b. Shiny fur
c. Sharp claws
Homework #4 – Fitness
Directions: Write one paragraph explaining what fitness is and what helps species have more fitness
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Charles Darwin
1. Vocabulary:
a. Variation: A ___________________ in species over time
2. Who is Charles Darwin?
a. The ___________________________ of __________________________!
b. 1831: Hired to go on a ___________________ on the HMS Beagle to study the ______________
and its __________________________
c. Studied the ______________________________ and ________________________ in his travels
3. Where did he go?
4. What did he observe?
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Variation:
o
_______________________ in physical
traits
o ________________________ between
the islands
o __________________________ Islands!
Adaptation:
o Feature that allows an organism
to better ______________________ in
its environment
o EXAMPLE: _______________________
_____________________________________
_____________________________________
____________________
Name:________________________________
Per:______
Practice #5 – CHARLES DARWIN
father
evolution
change
adaptation
Beagle
Galapagos
variation
environment
South America
Directions: Use the word bank above to fill in the blank space
1. _____________________________ is differences in physical traits
2. Darwin sailed around the world on the HMS _____________________________________
3. Darwin studied the variation of organisms on the ______________________________ islands
4. Darwin is considered to be the __________________________________ of evolution
5. A long neck to eat tall plants is considered an _________________________________________
6. Adaptations allow organisms to better survive in their ________________________________________
7. The Galapagos Islands are located off the coast of ___________________ ____________________________
8. A change is species over time is called ____________________________________________________
Homework #5 – Charles Darwin
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Darwin saw the following variations in
finches amongst the Galapagos Islands.
Some finches had thick beaks and others had
thin beaks, depending on their diet.
Using the picture to the left, choose which
bird would eat the following diets:
1. Soft berries:____________________________
2. Thick nuts:______________________________
3. Grass:____________________________________
4. Seeds:____________________________________
5. BONUS: WHY DID DARWIN OBSERVE VARIATIONS AMONG ISLAND SPECIES?
Charles Darwin: The Origin of Species
Few people have changed the world with the power of an idea. Charles Darwin, the British
naturalist who lived during the 1800s, was one of them. Darwin’s legendary book, On the Origin
of Species by Means of Natural Selection; or, the Preservation of Favoured Races in the Struggle
for Life, is frequently listed as one of the greatest books ever written. The three critical ideas he
developed in it are:



The fact that evolution occurs.
The theory of natural selection is the driving force or mechanism behind the process
of evolution.
The concept of phylogeny, that all forms of life are related to one another
genealogically, through their pedigree or "family's roots." (common ancestry)
Darwin began developing these ideas as a result of his experiences during a five-year voyage on
the British survey vessel H.M.S. Beagle, which sailed around the world on a mapping expedition
during the early 1830s. Darwin was on board to work as the ship's naturalist, to record
information about the geology, sea life, land animals and plants, and people that the Beagle would
discover. When he set sail in 1831, Darwin was twenty-two years old, fresh out of college,
fascinated with science, and deeply interested in geology and natural history. He was planning to
become a clergyman, partly because he thought it would allow him enough free time to pursue his
other interests.
As the mid-1800s approached, the idea of evolution posed a serious challenge to the then-popular
view that species were unchanging fixtures of nature. This concept, called the Fixity of Species,
was a perspective that European zoologists and botanists adopted as part of their culture, to reflect
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Western religion and the story of creation as laid out in the Bible. A key feature of the scientific
argument for "fixity" was the notion that the structure of each species was based on a model, ideal
form.
Darwin allowed himself to wonder if species were fixed or
prone to evolution. With the intense experience of five years
of living and working on the Beagle, collecting and
describing a vast number and variety of natural history
specimens, he developed into a first-rate naturalist –
actually, the best in the world. He came to see species
differently than those who saw perfection in them. Darwin
did not focus on the sameness of individuals; rather, he
thought it was important that individuals, like you and I,
vary in spite of the fact that we belong to the same species.
He realized that the variations could become the raw
material for evolutionary change.
One of the clues that moved Darwin to totally accept the principle of evolution involved a group
of small birds called mockingbirds. Mockingbirds are unspectacular animals with a wingspan of
about 10 inches. They live in many habitats in North, Central, and South America, from southern
Canada to Chile and Argentina. Darwin observed and collected them on the Galapagos, a cluster
of small islands off the coast of Ecuador, and sent his specimens back to London for study. After
the voyage, Darwin was surprised to learn that he had misclassified some of the birds because it
was difficult for him to tell the species apart from the subspecies. The physical traits of
mockingbird species and subspecies blended into one another. For Darwin, this meant that the
guidelines he had been trained to use to identify and classify animal and plant species, based on
the idea that each one ought to have an idealized "perfect" form - Fixity of Species - was an
arbitrary rule created by some scientists, nothing more than an untested assumption. It logically
followed that if species were not designed to be a series of perfect individual replicates,
evolutionary change - or "transmutation" of one species into another - was a possibility.
A second clue that led Darwin to embrace evolution had to do with fossils. Fossils are formed
when an organism dies and its remains become hardened by absorbing minerals from the earth in
which they were buried. Thus, fossils are direct evidence of life in the past and they have great
importance when considering a time-dependent concept such as evolution. In Argentina, Darwin
collected fossils of gigantic armor-plated beasts, megatheres, which were unlike anything else
anywhere in the world – nearly. Only the tank-like armadillos, which Darwin had also seen in
South America, bore any resemblance to them. Considering these extinct and living forms
together, Darwin theorized that megatheres and armadillos might be related. He thought they
might be part of a large group of South American mammals that had evolved body armor as a
protective adaptation. He speculated that an ancient "cousin" of the megatheres might have been
the ancestor of the armadillo.
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Darwin collected pieces of the evolutionary puzzle during his five years of sailing on the Beagle,
but to solve the puzzle by putting the pieces together into a basic model for the public to see
would take him several more decades of effort. His work was capped by publication of Origins in
1859, more than twenty years after he began his voyage on the Beagle. Origins was immediately
recognized as a major scientific success. In one of the quirkiest episodes in the history of science,
this happened to be the second time that Darwin published his explanation of evolution.
Some people were less than happy with the book’s publication. Since its central idea was that
evolution is an ever-present, unstoppable, fundamental law of nature, Origins became an angry
flashpoint for those who cared less about the biological history of animals and plants than they
cared about the deeper implications of the really big idea it represented – that in the middle 1800s
there were new, logically sound, evidence-based ways of looking at life that challenged the
religious ways of thinking that had been broadly accepted for centuries. Darwin knew that
evolution was one of the most important ideas for the human species to comprehend. He knew
that seeing us from an evolutionary perspective was more than peering through a telescope to
look back at our own primitive origins. Evolution was also a mirror and a microscope for looking
at ourselves as we are today.
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Name:________________________________
Per:______
Mutations, Evolution, Fitness & Darwin
Practice #6 – Mutation, evolution, fitness & Darwin
Mutation
Adaptation
Creationism
Population
Point mutation
Fitness
Controversy
Darwin
Frameshift mutation
Variation
Species
Evolution
Directions: Choose 10 of the terms above and define them below
TERM
DEFINTION
1.
2.
3.
4.
5.
6.
7.
8.
9.
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10.
Evidence for
Evolution
1. Vocabulary:
a. Fossil: Trace of an ____________________________ from the _______________________
b. Geography: The study of ______________________ features of the ___________________
c. Embryology: Branch of biology concerned with the study of ____________________
(fertilized cells)
d. Anatomy: The study of the ___________________________
2. What was darwin’s evidence?
1. Fossils:
o Showed that organisms ____________________ over ______________
o Found that _____________ organisms are found on the ______________ of rock
2. Geography:
Darwin saw that _____________ plants and animals looked __________________,
but were _________ identical to species on South America
o Thought that different ______________________ favored different ___________
o Over time, ___________ traits became ______________________ on the islands
o
3. Embryology:
o Study of __________________ and _________________________________________
o Found that embryos of ________________ species were _____________________
o EXAMPLE: The _________ of fish were the _______ of bird, reptile, and mammals
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4. Anatomy:
o Compared ______________ parts of different ______________
o Homologous structures:
o Similar in ______________, used for different things
o Analogous structures:
o Used for ___________ thing, ____________ different
Name:________________________________
Per:______
Practice #7 – Evidence for evolution
Directions: Use the vocabulary in the word bank above to answer the following questions in complete sentences
Homologous structure
Fossils
Organisms
Analogous structure
Geography
Fish gills
Anatomy
Embryology
Variation
1. What are the four sources for evolution, as observed by Darwin?
2. Why did Darwin think that the finches looked different on the various islands?
3. How did fossils provide evidence for evolution?
4. What is embryology?
5. When studying anatomy, Darwin found homologous structures. What are homologous
structures?
6. How did geography provide evidence for evolution?
7. Give one example of how embryology showed evidence for evolution
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Homework #6 – Evidence for evolution
Directions: Match each piece of evidence for evolution to its description
1. Anatomy
a. Darwin saw that island plants and animals looked alike,
but were slightly different
2. Geography
b. Darwin saw that embryos of different species were
similar
3. Embryology
c. Traces of organisms from the past showed that they
change over time
4. Fossils
d. Studying the bodies of different species showed that
they have similar structures, even if used for different
things
Real Life Evidence
1. Evidence of Whale Evolution: (pg. 318 Biology Book)
a. Fossils provide _______________ that whales came from hoofed ___________________________
b. Transitional fossils show characteristics of _________ __________ mammals and ____________
2. Actual fossils
3. What the fossils showed
a. Fossils showed that whales came from _____________________________________________________
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__________________________________________________________________________________________________
__________________________________________________________________________________________________
4. The Fossils
a. Dorudun:
40 million years ago
i. __________________ legs ___________________ on ________________________
ii. _______________ neck and longer tails = _________________ to today’s whales
b. Ambulocetus: 50 million years ago
i. Forearms had ________________________ and small _____________________
ii. Feet were for ________________________________________
c. Elomeryx: 52 million years ago
i. Whale shaped ________________________
ii. Teeth for _________________________ fish
iii. ____________________ bones in between ______________ and aquatic mammals
Name:________________________________
Per:______
Practice #8 – Real life evidence
Directions: Use the Venn Diagram below to compare and contrast the Dorudon fossil with the
Elomeryx fossil
homework #8 – Real life evidence
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Directions: Using the diagrams on the previous page, answer the following questions
1. Fossils showed that whales evolved from
a. lizards
b. land mammals
c. birds
2. Whales came from mammals
a. hundreds of years ago
b. thousands of years ago
c. millions of years ago
3. The dorudon fossils had
a. No hind legs
b. Hind legs that were useless on land
c. Powerful hind legs for land running
4. The Abulocetus fossil had
a. Forearms with fingers
b. No forearms
c. Forearms without fingers
5. The Elomeryx fossil had
a. Teeth for fish eating
b. Teeth for hunting
c. Teeth for berry eating
Theory of Natural Selection
1. Vocabulary:
a. Natural Selection: Process in which individuals that have inherited beneficial
_________________________ produce more _____________________ than do other individuals
b. Beneficial: _______________________, helpful
c. Population: All the _______________________ of a species that live in an ______________
d. Species: A group of organisms so similar to each other that they can
_____________________ and produce fertile ______________________
e. Fertile: Able to produce __________________________________________
2. Darwin’s theory of natural selection
1.
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5.
2. I
Natural
Selection
4.
3.
Better adapted = more
“fitness” = more likely to
survive and reproduce!
Name:________________________________
Per:______
Practice #9 – Natural selection
Species
Fertile
Natural Selection
Population
Variation
Darwin
Beneficial
Common
Adaptation
Directions: Use the word bank above to fill in the blank space
1. A ___________________________ adaptation is one that will help an organism survive and reproduce
2. _________________________came up with the theory of natural selection
3. A _______________________________ is a group of organisms that can breed and produce fertile
offspring
4. An ______________________________________ is a feature that allows an organism to better survive in its
environment
5. The ability to produce offspring is called being __________________________________
6. The process in which individuals that have inherited beneficial traits produce more offspring
than do other individuals is called _______________________________ _____________________________________
7. The differences among individuals in a species is called ________________________________________
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8. Good adaptations among individuals in a population will eventually be the most
_______________________________________
9. A _______________________________________ is all the individuals of a species that live in an area
homework #9 – Natural selection
Directions: For each of the following organisms, circle the adaptation that you think would
become the most common over time
5. Fish
a.
b.
c.
6. Frog
a.
b.
c.
7. Duck
a.
b.
c.
8. Wolf
a.
b.
c.
Fast swimmer
Long tail
Big eyes
Short tongue
Loud “ribbet”
Camouflaged skin
Big bill
Webbed feet
Dull feathers
Short nails
Friendly personality
Thick coat
1. Polar Bear
a. Skinny
b. White coat
c. Tired
2. Mole
a. Short tongue
b. Good hearing
c. Sharp claws
3. Dog
a. Good hearing
b. Short legs
c. Black coat
4. Eagle
a. Soft feathers
b. Sharp talons
c. White head
Natural Selection PRACTICE
Directions: Reading the following situations and identify the key concepts of Darwin’s
theory of natural selection
There are 3 types of polar bears: ones with thick coats, ones with thin coats, and ones with medium
coats. It is fall, soon to be winter. The temperatures are dropping rapidly and the bears must be kept
warm, otherwise they will freeze to death. Many of the bears have had 2 cubs each, but due to the
extreme temperatures, many mothers only have one cub left.
1. Which type of polar bear will not benefit from natural selection?
2. What are the variations within the polar bear population?
3. Which type of polar bear is the most fit in their environment?
4. Predict how the gene pool will change over time
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5. How will natural selection work on the polar bear population?
6. Identify the following in the polar bear population:
a. Beneficial adaptation:___________________________________________
b. Negative adaptation:____________________________________________
c. Species:___________________________________________________________
d. Population:_______________________________________________________
What is natural selection?
Directions: Write one paragraph explaining what natural selection is in your own words
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
__________________________________________________________________________________________________________________
Genetic Variation
1. Vocabulary:
a. Variation: ____________________________________________________________________________________
__________________________________________________________________________________________________
Natural selection acts on genetic variation!
2. What causes variation?
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_________________________________!
3. Why does variation matter?
a. Variation means there are _________________________ within a _____________________________
b. _____________________ variation = more likely to ________________ and _______________________
c. Variations ______________________ beneficial ________________________ over time
4. Adaptations
Picture
Description of adaptation
Name:________________________________
Why variation is beneficial
Per:______
Practice & Homework #10 – Genetic Variation
Directions: Answer the following questions in FULL SENTENCES, using your own words
1. Would evolution happen if there was no genetic variation?
2. What causes genetic variation?
3. Explain what a beneficial variation is
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4. What does natural selection act upon?
5. Give one example of a beneficial adaptation in wolves
6. Which individuals in a species will survive and reproduce?
7. What is the vocabulary word for the ability of an organism to produce more offspring
relative to other members of its population?
8. What is an adaptation?
9. Explain natural selection
10. Why is variation within a population important?
Why Does the Cheetah Lack Variation?
The cheetah, Acinonyx jubatus, is the sole member of its genus.
About 10,000 years ago - because of climate changes - all but one
species of the cheetah, jubatus, became extinct. With the drastic
reduction in their numbers, close relatives were forced to breed,
and the cheetah became genetically inbred. This has caused genetic
issues that today greatly add to the threat to their survival.
The study of biological inheritance is called "genetic research."
Genes, which are composed of DNA, store the information that an
individual inherits from his or her parents. Genes in one animal
vary from the same genes in another animal of the same species.
By looking at the amount of variation existing in genes, scientists,
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called "geneticists" can begin to understand the relationships of animals within population, and how infectious
diseases may affect that population. Also, by comparing the amount of variation between different species,
geneticists can help us understand the evolutionary process.
When geneticists looked at the amount of variation within the genes of the cheetah, they found that cheetahs exhibit
much lower levels of variation than other mammals. In most species, related individuals share about 80 percent of
the same genes. With cheetahs, this figure rises to approximately 99 percent.
The genetic inbreeding in cheetahs has led to low survivorship (a large number of animals dying), poor sperm
quality, and greater susceptibility to disease. Inbred animals suffer from a lack of genetic diversity. This means
cheetahs lack the ability to adjust to sudden changes in the environment, such as disease epidemics, and have
unusually high susceptibility to certain viruses. For example, if a virus gets into a healthy population of lions, not
every animal dies; just some do, because lions are genetically diverse. But if every animal is genetically the same,
like the cheetah, and one gets infected, all of them may become infected and die off. Because of their lack of
genetic diversity, a deadly virus could wipe out all of the worlds' wild cheetahs instead of just the susceptible
animals. It depends on a species' genetic differences.
Evolution eliminates traits in organisms that are least suited for survival. Some of the decline in the cheetah's
genetic diversity is accounted for by its specialization through natural selection. The decrease in genetic diversity
resulting from natural selection has benefited the species' survival as it has made the cheetah better adapted to its
environment. However, the effects of this occurrence are small when compared to the effects of the inbreeding that
occurred 10,000 years ago from a population bottleneck.
To increase genetic diversity in captivity, zoos take great care to make sure that only unrelated animals mate.
Scientists are working on ways to enhance breeding through artificial insemination, and in vitro fertilization (IVF).
Because of genetic inbreeding, male cheetahs have poor sperm quality. Abnormal sperm cannot swim properly,
reducing the chance of fertilizing eggs and producing offspring. Artificial insemination (A-I) is a laboratory
technique wherein scientists place sperm in the reproductive tract of a female. This means the sperm have less
distance to swim before reaching the eggs. Mating between male and female animals does not take place. Artificial
insemination has produced cheetah cubs in the United States. Using these technologies, A-I and IVF, semen, and
eggs can be collected from wild Namibian Cheetahs for use in captive breeding programs. Because Namibia has the
largest population of cheetahs, the genes represented in this population are important to captive cheetah survival
worldwide.
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Main Idea:
Supporting
Detail:
Supporting
Detail:
Supporting
Detail:
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Speciation
1. Vocabulary:
a. Speciation: The rise of two or more species from ones ____________________ species
b. Reproductive isolation: Members of populations can no longer __________
successfully
c. Behavioral isolation: Isolation caused by differences in ____________________ or mating
behaviors
d. Geographic isolation: ____________________________ barriers that divide a population
e. Temporal isolation: _____________________ prevents reproduction between populations
2. Types of speciation
Speciation
Reproductive Isolation
Behavioral
Isolation
Geographic
Isolation
Temporal
Isolation
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Name:________________________________
Per:______
Practice #11 – Speciation
1. What
arise?
are the three ways that new species
2. How
does geographic isolation prevent
species from mating (reproductive isolation)
3. How does temporal isolation prevent species from mating (reproductive isolation)
4. How does behavioral isolation prevent species from mating (reproductive isolation)?
5. Explain in your own words how new species are formed
Homework #11 – Speciation
Behavioral isolation
Geographic isolation
Temporal isolation
Directions: Use the word bank above to indicated whether each of the following are
examples of behavioral, geographic, or temporal isolation
1. Mate at different times of the year:___________________________________________________________________
2. Separated by a river:__________________________________________________________________________________
3. Different mating rituals:______________________________________________________________________________
4. Populations separated on islands:___________________________________________________________________
5. Populations of parrots mate at different times of the day:_________________________________________
6. Populations of deer separated by mountains:_______________________________________________________
7. Differences in courtship songs:______________________________________________________________________
8. Populations of fish separated by land:______________________________________________________________
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9. Populations of peacocks with different mating dances:____________________________________________
10. Population A mates in the Spring, Population B mates in the Fall:________________________________
Summer Night Lights
by Genny Fannucchi
Lightning bugs....Have you ever wondered about the small,
blinking creatures that light up summer nights? Lightning bugs,
also called fireflies, are not simply bugs and are not flies. They
are beetles and part of a scientific family that contains the
largest order of living things—290,000 species at last count. In
fact, there are about 136 different species of fireflies
illuminating earth's summer nights.
Fireflies are easy to locate. Go outside at different times during
the evening and watch for small twinkling lights in the air. Good places to find fireflies are over
meadows or lawns and at the edge of woods or streams. Fireflies are carnivorous. They eat other
insects, small animals in the soil, and snails. Fireflies overwinter as larvae buried in the soil and
emerge in the spring to feed. In summer, they pupate for about 2½ weeks within a small earthen
cell before emerging as adults. The adult fireflies signal each other with their lights and mate. The
female's eggs are laid a few days after mating, on or slightly under soil. The eggs hatch in 4 weeks.
The larvae, once hatched, begin to feed until fall. They burrow underground and overwinter.
The summer evening light shows that you see are performed by male fireflies. They flash patterns
of light to females. The females signal in response from perches in or near the ground. When the
male sees the female's flash he continues to signal and moves closer. Eventually, through a series
of flashes, they find each other and mate. Each species of firefly sends different mating signals.
In fact, a beetle specialist or a keen observer can recognize most species by the number, duration,
and time lapses between flashes.
The male firefly of the species Photinus pyralis, beams a single half-flash during a forward rising
flight movement. It looks like the letter "J." The female responds with a single flash. Another
species, Photinus consumilis, signals his mate with a rapid succession of flashes. She responds with
two beams. In general, males will not fly down to a female that sends the wrong species signal. But,
some females of differing species have evolved the ability to mimic the response flashes of species
other than their own. As the male flies down to a mimicking female, he is captured and eaten, gulp!
The light given off by fireflies during their abdominal flashes is called bioluminescence. It happens
when oxygen and the organic compound luciferin react together in the presence of the enzyme,
lucifereace. This creates light. Although other insects can produce light, fireflies are the only
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insects that can flash their light on and off in distinct signals. Even the eggs and larvae of some
firefly species glow. That's where the name "glow worm" comes from.
Name:________________________________
Per:______
Practice #12 – Summer Night lights
1. What type of speciation did the article talk about?
2. How were the mating rituals different in different species?
3. What did you learn from the article?
4. How does speciation happen over time?
5. Explain the connection between speciation and evolution
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