catalyst #4: september 16th, 2013 (4 minutes)

Catalyst #4: September 16th, 2013 (4 minutes)

1. Give one example of an adaptation and explain why it is an adaptation.

2. Define evolution by natural selection.

3. Give an example of geographic isolation.

4. How are convergent and divergent evolution different?

Today’s AgendaCatalyst (5 minutes)Speciation Beach Ball review (5

minutes)Evidence of Evolution (15 minutes) ThinkTacToe (20 minutesHomework:

None Honors: 9 weeks project due September 30th

Announcements

Mastery grades Office hours tomorrow Dojo review Binder quiz this week ;) Parent teacher conferences on Thursday

Unit 3: 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?

Evaluation: Natural Selection Crawlers from The Descent

Humanoid Cave-dwelling Blind No pigment Moist skin Incredible grip/climbing

abilities Bat-like ears Echolocation Carnivorous (raw meat)

Evaluation: A valid example of natural selection?

Are the crawlers a valid example of natural selection?

What are their adaptations? Are they favorable? Is it believable?

“Regressive Evolution”

Cave dwelling organisms (Troglobites)

Instead of “gaining” favorable adaptations, they lose adaptations they no longer need.

Beach Ball Review

Divergent evolutionSpeciationSpeciesConvergent evolutionGeographic isolationReproductive isolationCommon ancestor

Today’s SPI and Objectives

SPI 3210.5.3 Recognize the relationships among environmental change, genetic variation, natural selection, and the emergence of a new species.

SWBAT identify the various forms of evidence supporting evolution

SWBAT explain how homologous structures demonstrate common ancestry (relatedness) and support evolutionary theory

SWBAT identify examples of vestigial structures and explain how vestigial structures provide evidence supporting evolution

Evidence of Evolution

BiologyUnit 3Chapter 15, Section 2


Evolution by natural selection is considered the best scientific explanation for the existence and diversity of life Scientific= testable & observable Keep in mind that science cannot

prove or explain everything, however

Scientists use many forms of scientific evidence in support of evolution


We will focus on 4 forms of evidence Fossils Homologous structures Vestigial structures DNA sequencing

Homologous Structures Definition: Structures with similar

composition, placement and form but different functions Examples: Human arm, cat leg, horse

leg, dolphin flipper, and bat wing

Homologous Structures

Homologous Structures

How do homologous structures provide evidence in support of evolution? Homologous structures suggest that

organisms evolved from and share a common ancestor because of their similar bone structure and placement.

They have different functions because each species adapted to different environments

Analogous Structures

What about structures with the same function?

Analogous structures are structures that evolved in unrelated species, but have the same function in different organisms Example: Bird wings vs. insect wings

They are found in unrelated species that only use them for similar functions. These DO NOT provide evidence of

evolution

Analogous Structures

Mammals and insects both use their legs to walk. However, their limbs are made of different types of tissues and these organisms are not closely related.

These are analogous structures

Vestigial Structures

Definition: Structures with little or no known function in one organism but known to have a significant function in other organisms Examples: Snake pelvis, Kiwi wings,

human appendix


How do vestigial structures provide evidence in support of evolution? These structures suggest that a

species evolved because they are known to have important functions in other organisms, so they likely did in an ancestor of the species

Evolution Review ThinkTacToe You must complete at least 5 THINK boxes. Regular: You must complete one box in

each column. (i.e. 1 from T, 1 from H, 1 from I, etc.)

You may choose ANY boxes in the column. (Honors: 3 of your boxes must be from the “N” or “K” columns.)

On your own sheet of paper, write whatever column and your answer in COMPLETE SENTENCES

Reminders

Honors 9 weeks projects Office hours Binder quiz

Catalyst #5: September 17th, 2013

ALA #1

Agenda

Catalyst: 10 minutes ActivExpression Review: 10 minutes Evidence of Evolution, part 2: 10

minutes Manipulatives: 15 minutes

Homework: Evidence for Evolution Homework

Unit 3 Study Guide due Monday Honors 1st 9 weeks projects

Announcements

Parent teacher conferences on Thursday

Today’s SPI and Objectives

SPI 3210.5.3 Recognize the relationships among environmental change, genetic variation, natural selection, and the emergence of a new species.

SWBAT identify the various forms of evidence supporting evolution

SWBAT explain how homologous structures demonstrate common ancestry (relatedness) and support evolutionary theory

SWBAT identify examples of vestigial structures and explain how vestigial structures provide evidence supporting evolution


BiologyUnit 3Chapter 15, Section 2

Question 1

Define evolution.

Question 2

Define speciation.

Question 3

Octopi are able to change color and texture to blend in with their environments. What type of adaptation is this AND what environmental factor contributes to this adaptation?

Question 4Male peacocks with the most colorful tail feathers are most likely to finding a mate. Female peacocks choose mates based on the color of their tail feathers. In reality, not all males have bright, large tails, and this was especially true a few thousand years ago. Females are not likely to choose those males as mates. Predict which tail feathers the majority of the male peacock population have today using the four principles of natural selection.

Question 5

Define divergent evolution.

Question 6

Rainbow trout spawn (reproduce) in the spring. Brown trout spawn in the fall. These two types of organisms are not able to mate and not the same species. Is this an example of geographic or reproductive isolation?

Question 7

Is this a result of geographic or reproductive isolation?

A forest fire causes the permanent separation of a group of deer from their native population, causing the small group to interbreed only with one another. Over time, the group becomes an entirely different species.

Question 8

Ducks and platypuses both have bills and webbed feet. However, they are not related. Is this an example of convergent or divergent evolution?

Question 9

Darwin studied finches on the Galapagos Islands. These birds had evolved different beaks to eat the different available food on different islands.

Convergent or divergent evolution?

Question 10:

Give an example of two homologous structures.

Fossil Record

Definition: Preserved remains or imprints of organisms that are found in various levels of the earth Bones, shells, imprints,

etc. Older fossils are found

deeper in the earth; newer fossils are found near the earth’s surface

Fossil Record

How does the fossil record provide evidence of evolution?

Many fossils are intermediate forms, whose features show a transition from ancient species to modern species Features are in between those of ancient and

modern organisms This suggests that many species of

organisms have gradually changed over time Evolution

Fossil Record

Fossil Record: Transitional Forms

OLDER

MODERN

DNA Sequencing

Definition: Comparison of all of the genes (genome) found in different species of organisms Example: Human vs.

chimpanzee DNA

DNA Sequencing

How does DNA sequencing provide evidence of evolution? DNA sequencing shows many

similarities in the genome (all of the genes) of different species

Species with higher percentages of their DNA (genome) in common are thought to be more closely related and to share a common ancestor

Sample Question

Which two species are most closely related?

Species 1 and 3

Species DNA Sequence

Species 1 ACT GGT CCA

Species 2 ACT GGC TCA

Species 3 ACT GTT CCA

Species ACC GGT CTA

Sample Question

Which two species are most closely related?

Species 3 and 4

Species DNA Sequence

Species 1 CCC GTG ATC TTA

Species 2 CTC GGG ATC TCA

Species 3 CCG TGG ATC TCA

Species 4 CCG TTG ATG TCA

CFU

Which of the following is the best definition of analogous structures?A. Structures that evolved in unrelated species but

have the same functionB. Structures with little or no known function in one

species but an important function in other species

C. Structures with similar form and placement but different functions

D. Structures left behind in various layers of the Earth

Answer: A.

CFU

Which of the following is the best definition of homologous structures?A. Structures that evolved in unrelated species but

have the same functionB. Structures with little or no known function in one

species but an important function in other species

C. Structures with similar form and placement but different functions

D. Structures left behind in various layers of the Earth

Answer: C.

CFU

Ostriches have wings even though they do not fly. What type of structures are the ostrich wings?

Why do scientists suggest ostriches have wings?

Answer: Vestigial structures; because they were used (function) in an ancestor species

CFU

The structures below are similar in form but have different functions in different species. What type of structure are they?

Why are they different? Answer: Homologous structures; the

species adapted to different environments

CFU

The pictures below show fossils of related species. The fossil on the right was found deeper in the earth than the one on the left.

Which species is thought to be older? Which species is thought to have

evolved more recently?

Manipulatives: Instructions

Sort the cards into 4 piles—one for Homologous Structures, one for Analogous Structures, one for Vestigial Structures, and one for Fossils

Check your piles with Ms. M when complete

Then begin on your homework

Catalyst #5: September 18th, 2013

Read the article “T-Rex as a Scavenger” and answer the following questions.

1. What is the difference between a scavenger and a predator?

2. What was Horner’s evidence for the T-Rex as a scavenger?

3. What evidence did dePalma and colleagues provide for T-Rex as an apex predator?

Today’s Agenda

Catalyst (15 minutes)Evolution Stations (25 minutes)Closing (Remainder) Homework:

Study for Unit 3 exam Honors: 9 weeks project due September 30th

Announcements

Parent teacher conferences tomorrow Regular: bring your study guide tomorrow

Review Stations

Moving desks How we rotate Work Expectations

Reminders

Unit 3 exam on Monday Unit 3 study guide due on Monday Honors 9 week projects

catalyst #4: september 16th, 2013 (4 minutes)

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