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Catalyst: September 17th, 2014 (10 minutes)
We will be doing an Active Expression review before our quiz. You should also have your HOMEWORK on your desk.
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Agenda Evolution Active Expression Review (10 minutes)
Natural Selection Quiz (10 minutes) Evolution of Desert Snakes Group Activity (Remainder) Reminders: DBA #5: 9/29 HP 9/26 Edmodo assignment due TOMORROW
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Announcements
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Active Expression Review
What environmental factor (Assignment 2) contributes to fish with different mouth shapes? Which of the following is not an example of an adaptation? a. Artic hares with white fur b. Claws on a lion c. Bright colors on a toxic frog d. White fur on a forest dwelling squirrel
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Active Expression Review
Principle 1 of natural selection (Assignment 2) states that all populations have _____________ variation. T/F A green lizard living in the desert can change to green in order to avoid predators. Why do peppered moths during the Industrial Revolution demonstrate natural selection? White and black moths were able to interbreed and create a new, more camouflaged species of moth. Pollution of birch trees pushed the moth population to the brink of extinction. As the trees grew darker, darker moths were able to survive, reproduce, and pass on their genes; thus, over time, the peppered moth population consisted of primarily dark moths. Light colored moths were able to transform their color to darker in order to avoid the mutant birds that were able to hunt them with super cool laser vision.
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Natural Selection Quiz
Natural Selection and Adaptations Quiz: To be completed on your Active Expression. YOU MAY BEGIN ON QUIZ IMMEDIATELY. You should also have your HOMEWORK on your desk.
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Desert Snakes Argumentation Activity
As a group, you will develop an argument and evidence for the evolution of different types of desert snakes. Argumentation is a central key to scientific writing. First, develop a claim. A claim is a clearly stated stance. Example: Second, collect evidence using the handouts to support your claim.
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Poster Expectations Claim clearly stated
At least 4 pieces of evidence to support claim Evidence is quantitative. Group expectations: Everyone in the group contributes. If necessary, assign roles. Volume and movement
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Catalyst: September 13th, 2013 (10 minutes)
Complete problem 22 on your ALA sheet. (You should also have a class copy). A-What is the question asking you? L-Where do you look to find your answer? A-What is your answer and WHY?
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Today’s Agenda Catalyst: ALA 3 (7 minutes)
Evolution and Speciation (20 minutes) Speciation questions and Trashketball (Remainder) Reminders: DBA #5: Sept. 29th HP: Sept. 26th
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Announcements Accountants
Edmodo assignment due by MIDNIGHT tonight (I will be here after school) No school for you tomorrow! Parent Teacher conferences
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Unit 2: Guiding Questions
What determines which organisms survive and which do not? Do species ever change? How do scientists believe all of the species that exist today were formed? What evidence is there to support evolution?
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Today’s SPI and Objectives
SPI Recognize the relationships among environmental change, genetic variation, natural selection, and the emergence of a new species. SWBAT define species, speciation and identify factors that result in speciation SWBAT distinguish between convergent and divergent evolution
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Evolution & Speciation
Biology Unit 3 Section 15.2 Evolution & Speciation
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Review Review: What is evolution?
Evolution is the gradual change in a population of organisms over time The key is over a long period of time
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Review What is one of the main ways evolution occurs?
One of the main ways evolution occurs is through natural selection Who developed this concept?
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Natural Selection Examples of natural selection: Peppered moths
Antibiotic-resistant bacteria Green/brown lizards
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Disclaimer We are going to be talking about
Different theories. They may conflict with your beliefs (and that’s okay). Its something that we need to cover in order to prepare you in Biology.
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Natural Selection & Evolution
Natural selection causes a population to evolve, but it may or may not create a new species Deer mice: dark brown light brown mice Moths: Light moths dark moths These examples of evolution did not create a new species, however
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Species REVIEW: Key Term: A species is a group of organisms that can mate and produce fertile offspring Fertile offspring means the offspring are also able to reproduce
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SPECIES EXAMPLE Homo sapiens: (scientific name for humans)
Male and female homo sapiens with any variation can mate to produce children. These children can grow up to reproduce with other humans as well.
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SPECIES NON-EXAMPLES Any animals that cannot physically mate.
Any animal that can physically mate, but cannot reproduce offspring. Any animal that physically mate, and reproduce INFERTILE or Sterile offspring.
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SPECIES NON-EXAMPLE A lion and tiger can mate and produce the animal known as the Liger. A Liger is a sterile animal that cannot have offspring. Since the offspring of the lion and tiger does not produce fertile offspring, they are considered separate species.
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Introduction Even humans?
From where do scientists suggest that all organisms that exist today came? Key Point 1: Many scientists believe that all species that exist today evolved from a common ancestor What is an ancestor? Even humans? Even humans! From primates (chimpanzees)
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Speciation If a population of organisms adapts to its environment and can no longer reproduce with other populations, a new species has evolved. Key Point 2: Speciation is the development of a new species of organisms from an existing species This typically occurs over a very long period of time
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Causes of Speciation Key Point 3: Speciation can be caused by:
Geographic isolation—a population is separated by a physical barrier May be separated by a mountain, canyon, river, etc. or because of flooding or other changes in habitat Organisms no longer mate and are forced to develop different adaptations to survive Eventually they cannot reproduce together
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Geographic Isolation
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Adaptive Radiation Adaptive Radiation occurs when diversify quickly into different forms-particularly after a change in the environment makes new resources or niches available. Niche= the physical environment (habitat) that an organism occupies and the adaptations that allow for life in that habitat
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Causes of Speciation Key Point 4: Reproductive isolation
Populations no longer mate or produce fertile offspring due to different mating seasons, different anatomies, or different number of chromosomes in their gametes
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CFU 1 Two populations of toads began mating during different times of the year and no longer reproduce. Over time, two different species of toads have developed. Is this a result of geographic or reproductive isolation?
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CFU 2 A flood forces one population of snakes to move to another habitat. Over time, this population evolves into a new species of snake as it adapts to its environment. Is this a result of geographic or reproductive isolation?
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CFU 3 Two different species of mountain goats have appeared on opposite sides of the Rocky Mountains. Is this a result of geographic or reproductive isolation?
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Divergent Evolution Key Point 5: When one species evolves into two or more different species, this is known as divergent evolution Example: Scientists believe that various species of cats (cheetahs, leopards, jaguars, etc.) evolved from a common ancestral species many years ago
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Convergent Evolution Key Point 6: When different species change over time to develop similar adaptations due to similar environments this is known as convergent evolution Example: Sharks and dolphins are different species, but over time they have developed similar adaptations to survive in their environments
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CFU 4 Each species of mammal below is believed to have evolved from a common ancestral species Convergent or divergent evolution? Why?
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CFU 5 The thorny devil and Texas horned lizard are two different species of lizards that have adapted over time to eat similar foods and behave in similar ways because of similar environments Convergent or divergent evolution? Why?
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CFU 6 These two tortoises above belong to different species. Scientists believe they evolved from a common ancestor but developed different adaptations to survive in their environments. Convergent or divergent evolution?
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CFU 7-8 What is the term used to describe the development of a new species from an existing species? Speciation What term is used to describe a group of organisms that can reproduce and produce fertile offspring? Species
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Human Evolution
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Speciation Questions Speciation Trashketball
I will give you a certain amount of time to answer each question. When it is your team’s turn, I will randomly call on someone to answer. Get it right = take a shot
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