Mutation: A change in an organisms _________________
Point mutation: A mutation that happens when an incorrect nucleotide is ________________ into a DNA molecule
Frameshift mutation: The addition or ______________________ of a nucleotide during a DNA sequence
Why do Mutations matter?
Mutations cause _________________ in ________________.
Mutations are what cause individuals within a species to have ________________
ractice #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
Why are they called mutant turtles?_____________________________________________________________________________________________________________
Are their mutations beneficial? Why or why not?_____________________________________________________________________________________________________________________________________________________________________________________________________________________
Are the Teenage Mutant Ninja Turtles similar to their species or different?
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 the controversy will unfold, but a few quick conversations with members of the opposing sides shows that the confrontation is far from over.
In our classroom
Evolution is ________________ of the High School biology _________________________________
You are entitled to ________________________________ everything and encouraged to _______________________________ whatever you would like
Practice #2 – Evolution controversy
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.
Evolution is a scientific fact
Evolution is something you should either believe in, or not believe in
Evolution is a process that involved the origin of life
Evolution is primarily concerned with the origin of humans
According to evolution, people came from monkeys a long time ago
Evolution was first proposed and explained by Charles Darwin
Evolution is something that happened in the past and is not happening now
Evolution can be compatible with all the world’s major religions
Evolution is only a theory
There is little evidence for evolution
Evolution theory has been tested many times, and has always been supported by the evidence
Evolution is a totally random process, or a series of “accidents”
Homework #2 – Evolution controversy
Are there any other issues you can think of that are similar to evolution (they are controversial)?
Explain what the word “controversial” means in your own words.
Variation: A ___________________ in species over time
Who is Charles Darwin?
The ___________________________ of __________________________!
1831: Hired to go on a ___________________ on the HMS Beagle to study the ______________ and its __________________________
Studied the ______________________________ and ________________________ in his travels
Where did he go?
What did he observe?
Practice #5 – CHARLES DARWIN
Directions: Use the word bank above to fill in the blank space
_____________________________ is differences in physical traits
Darwin sailed around the world on the HMS _____________________________________
Darwin studied the variation of organisms on the ______________________________ islands
Darwin is considered to be the __________________________________ of evolution
A long neck to eat tall plants is considered an _________________________________________
Adaptations allow organisms to better survive in their ________________________________________
The Galapagos Islands are located off the coast of ___________________ ____________________________
A change is species over time is called ____________________________________________________
Homework #5 – Charles Darwin
arwin 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:
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 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.
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.
Mutations, Evolution, Fitness & Darwin
Practice #6 – Mutation, evolution, fitness & Darwin
Directions: Choose 10 of the terms above and define them below
Fossil: Trace of an ____________________________ from the _______________________
Geography: The study of ______________________ features of the ___________________
Embryology: Branch of biology concerned with the study of ____________________ (fertilized cells)
Anatomy: The study of the ___________________________
What was darwin’s evidence?
Practice #7 – Evidence for evolution
Directions: Use the vocabulary in the word bank above to answer the following questions in complete sentences
What are the four sources for evolution, as observed by Darwin?
Why did Darwin think that the finches looked different on the various islands?
How did fossils provide evidence for evolution?
What is embryology?
When studying anatomy, Darwin found homologous structures. What are homologous structures?
How did geography provide evidence for evolution?
Give one example of how embryology showed evidence for evolution
Homework #6 – Evidence for evolution
Directions: Match each piece of evidence for evolution to its description
a. Darwin saw that island plants and animals looked alike, but were slightly different
b. Darwin saw that embryos of different species were similar
Natural Selection: Process in which individuals that have inherited beneficial _________________________ produce more _____________________ than do other individuals
Beneficial: _______________________, helpful
Population: All the _______________________ of a species that live in an ______________
Species: A group of organisms so similar to each other that they can _____________________ and produce fertile ______________________
Fertile: Able to produce __________________________________________
Darwin’s theory of natural selection
Better adapted = more “fitness” = more likely to survive and reproduce!
Name:________________________________ Per:______ Practice #9 – Natural selection
Directions: Use the word bank above to fill in the blank space
A ___________________________ adaptation is one that will help an organism survive and reproduce
_________________________came up with the theory of natural selection
A _______________________________ is a group of organisms that can breed and produce fertile offspring
An ______________________________________ is a feature that allows an organism to better survive in its environment
The ability to produce offspring is called being __________________________________
The process in which individuals that have inherited beneficial traits produce more offspring than do other individuals is called _______________________________ _____________________________________
The differences among individuals in a species is called ________________________________________
Good adaptations among individuals in a population will eventually be the most _______________________________________
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
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.
Which type of polar bear will not benefit from natural selection?
What are the variations within the polar bear population?
Which type of polar bear is the most fit in their environment?
Predict how the gene pool will change over time
How will natural selection work on the polar bear population?
Identify the following in the polar bear population:
Natural selection acts on genetic variation! _________________________________________________________________________________________________
What causes variation?
Why does variation matter?
Variation means there are _________________________ within a _____________________________
_____________________ variation = more likely to ________________ and _______________________
Variations ______________________ beneficial ________________________ over time
Description of adaptation
Why variation is beneficial
Practice & Homework #10 – Genetic Variation
Directions: Answer the following questions in FULL SENTENCES, using your own words
Would evolution happen if there was no genetic variation?
What causes genetic variation?
Explain what a beneficial variation is
What does natural selection act upon?
Give one example of a beneficial adaptation in wolves
Which individuals in a species will survive and reproduce?
What is the vocabulary word for the ability of an organism to produce more offspring relative to other members of its population?
What is an adaptation?
Explain natural selection
Why is variation within a population important?
Why Does the Cheetah Lack Variation?
he 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, 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.
Speciation: The rise of two or more species from ones ____________________ species
Reproductive isolation: Members of populations can no longer __________ successfully
Behavioral isolation: Isolation caused by differences in ____________________ or mating behaviors
Geographic isolation: ____________________________ barriers that divide a population
Temporal isolation: _____________________ prevents reproduction between populations
Types of speciation
Practice #11 – Speciation
What are the three ways that new species arise?
How does geographic isolation prevent species from mating (reproductive isolation)
How does temporal isolation prevent species from mating (reproductive isolation)
How does behavioral isolation prevent species from mating (reproductive isolation)?
Explain in your own words how new species are formed
Homework #11 – Speciation Directions: Use the word bank above to indicated whether each of the following are examples of behavioral, geographic, or temporal isolation
Mate at different times of the year:___________________________________________________________________
Separated by a river:__________________________________________________________________________________
Different mating rituals:______________________________________________________________________________
Populations separated on islands:___________________________________________________________________
Populations of parrots mate at different times of the day:_________________________________________
Populations of deer separated by mountains:_______________________________________________________
Differences in courtship songs:______________________________________________________________________
Populations of fish separated by land:______________________________________________________________
Populations of peacocks with different mating dances:____________________________________________
Population A mates in the Spring, Population B mates in the Fall:________________________________
Summer Night Lights
by Genny Fannucchi
ightning 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 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.
Practice #12 – Summer Night lights
What type of speciation did the article talk about?
How were the mating rituals different in different species?
What did you learn from the article?
How does speciation happen over time?
Explain the connection between speciation and evolution