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May 9, 2017 Aims:

SWBAT analyze and evaluate the two proposed theories for

evolution.

Agenda

1. Do Now

2. Class Notes

3. Guided Practice

4. Independent Practice

5. Practicing our AIMS:

E.2-Evolving Theories

How will you help our class earn all of our S.T.R.I.V.E. Points?

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Aim Check:

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OBJECTIVES: By the end of class, students will be able to…

SWBAT analyze and evaluate the two proposed theories for evolut ion.

DO NOW These fossils are a series of skulls and front leg fossils of organisms believed to be ancestors of the

modern-day horse.

1. Give two similarities between the skulls that might lead to the conclusion that these are all related

species.

2. What is the biggest change in skull anatomy that occurred from the dawn horse to the modern

horse?

SCIENCE 8

Evolv ing Theories

E.2

Name: _____________________________

Date: ________________________________

Homeroom: _________________________

Evolution

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CLASS NOTES

Gradual changes in fossils have provided the ev idence that species have

changed over generations…

EVOLUTION:

but HOW?!?!?

BATTLE OF THE ADAPTATIONS

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ADAPTATION:

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LAMARCK’S THEORY OF EVOLUTION:

o An organism can by using its body

in certain ways

o The characterist ics that an organism acquires during its life are then

Example: Giraffe Evolut ion According to Lamarck

Narrate this picture in the box below, using a Lamarckian explanation of evolut ion

Analyze like a scientist:

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DARWIN’S THEORY OF EVOLUTION:

o An organism without these adaptations o Over generations, the as more offspring

inherit the adaptation

One day a crab is born with an even larger claw….

Natural selection will continue and the population evolves even further

Example: Giraffe Evolut ion According to Darwin

Apply Darwin’s explanation of evolut ion to explain Giraffe evolut ion

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GUIDED PRACTICE Read the two theories below that hypothesize how elephants have evolved to have long trunks. For

each theory, state whether it demonstrates Lamarck’s theory or Darwin’s and JUSTIFY your answer with

evidence.

Theory A

Many years ago, elephants fed primarily from bushes that laid low to the ground. They had a short

snout of a few inches that they used to place leaves in their mouth. However, after a great flood wiped

out many shrubs, elephants had to adapt to their new environment to survive.

They used their snouts to reach higher and higher for leaves, and eventually their snouts grew into

longer trunks. This adaptation was then passed on to their offspring, which also continued to stretch

and elongate their trunks until they developed into the structures we know today.

Theory B

Many years ago elephants had primarily short snouts. Though all snouts were only a few inches long,

some elephants had longer snouts than others. After a great flood wiped out many shrubs, the

elephants with the shortest snouts died out because they were not able to reach enough leaves on

trees. The other elephants survived and those with the longest snouts were able to survive the best and

reproduce the most.

Over time as the elephants with the longest trunks continued to survive and reproduce the most, and

those with the medium or short trunks reproduced less, the population changed and ultimately

contained only the long-trunked elephants we know today.

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INDEPENDENT PRACTICE WHO SAID IT?-

Write Darwin next to statements that are true according to Darwin’s Theory.

Write Lamarck next to statements that that describe Lamarckian evolution.

“Evolution occurs when organisms adapt to meet their needs in an

environment.”

“Whole populations, not individual organisms, evolve over time

based on their environment.”

“Adaptations are inherited”

“Adaptations are acquired based on use.”

“If an organism is not well adapted to its environment, it dies.“

“If an organism struggles in an environment it adapts.”

Directions: Answer each question to the best of your ability.

1. The illustration below shows an insect resting on some green leaves.

The size, shape, and green color of this insect are adaptations that would most likely help the insect

to

A. compete successfully with all birds

B. make its own food

C. hide from predators

D. avoid toxic waste materials

2. A woman wants to become a faster runner. She trains and practices until she builds enough muscle

strength to dramatically increase her speed. The woman’s muscle strength is an example of

A. an acquired trait

B. evolution

C. an inherited adaptation

D. natural succession

3. If the woman in #2 reproduced, her offspring

A. would be equally fast runners because they will inherit her muscle strength

B. would be equally fast runners because mutations are passed on

C. would not necessarily be fast because her muscle strength was an acquired trait

D. would not necessarily be fast because they may not inherit her gene for muscle strength

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4. Young birds that have been raised in isolation from members of their species build nests

characteristic of their species. This suggests that the nest -building behavior is

A. an adaptation that was genetically inherited from parents

B. an adaptation learned by watching members of their species

C. a disadvantage to the survival of the species

D. a direct result of the type of food the bird eats

5. The teeth of carnivores are pointed and are good for puncturing and ripping flesh. The teeth of

herbivores are flat and are good for grinding and chewing. Which statement best explains these

observations?

A. Herbivores have evolved from carnivores.

B. Carnivores have evolved from herbivores.

C. The two types of teeth most likely evolved as a result of the needs of an organism.

D. The two types of teeth most likely evolved as a result of natural selection.

6. Woolly mammoths became extinct thousands of years ago, while other species of mammals that

existed at that time still exist today. These other species of mammals most likely exist today because,

unlike the mammoths, they

A. produced offspring that all had identical inheritable characteristics

B. did not face a struggle for survival

C. learned to migrate to new environments

D. had certain inheritable traits that enabled them to survive

7. One ecologist theorized that the beaver has evolved from an ancient ancestor called the Sciuridae,

which resembled a squirrel. Unlike the Sciuridae, a beaver has larger teeth for cutting wood and

webbed feet and a large flat tail that help it move in the water. The ecologist claimed that when

there was a need for Sciuridae to acquire food from water, instead of land, organisms without these

traits for swimming died out and the modern beaver evolved. This theory is best classified as

A. Lamarckian evolution

B. Adaptation

C. Darwinian evolution

D. Selective breeding

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HIGH SCHOOL CHALLENGE Read the question below and the answer that a student wrote in response.

Question: A species of birds called the rock dove feeds primarily on worms and bugs located

on the ground. Since there has been an abundance of food at ground-level in the Catskills

Mountains, the majority of the rock doves in that region have never used their wings to fly. In

fact, many are not able to fly at all. Explain how a shortage of food on the ground could

cause this species to evolve.

Student Answer: The rock doves are going to evolve in response to their environment. Birds

with small, weak wings will have to adapt and start to f ly to f ind food and evolve.

Explain why this student’s answer is WRONG. Then provide a better explanation of how the

rock dove would evolve through Darwin’s theory.

9. Use Darwin’s theory to describe how a population of zebras, being hunted by lions, might

evolve to become faster over time.

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A researcher studying insects discovered a species of bumble bees in which males perform a

dance-like movement in order to attract females. He collected samples of these bees and

introduced them into the bee collection in his lab. He noticed that the new species was far

more successful in mating with the female bees and reproduced rapidly. Use Darwin’s theory.

Summarize what you learned in today’s lesson. Be sure to include a thorough explanation of

the following terms and concepts: adaptation, Lamarckian evolution, and Darwinian

evolution. Be sure to explain which theory is more accurate and WHY.

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Science 8

E.2:

Evolving Theories

Name: _____________________________

Date: _______________________________

Homeroom: _________________________

Quick Notes:

SKILL SNAPSHOT

Like A Scholar?

Yes No

Redo?

Yes No

Directions: Support your selection by jotting down your reasoning.

Question Reasoning

1. Some behaviors such as mating and caring for young are

genetically determined in certain species of birds. The

presence of these behaviors is most likely due to the fact

that

A. birds do not have the ability to learn

B. these behaviors helped birds to survive in the past

C. individual bids need to learn to survive and

reproduce

D. within their lifetimes, birds developed these behaviors

2. A characteristic that an organism exhibits during its

lifetime will only affect the evolution of its species if the

characteristic:

A. results from isolation of the organism from the rest of

the population

B. is due to a genetic code that is present in the

gametes of the organism

C. decreases the number of genes in the body cells of

the organism

D. causes a change in the environment surrounding the

organism

3. Which of the following statements is NOT true according

to Darwin

A. organisms that are well adapted to their

environments successfully reproduce

B. organisms that that lack necessary adaptations may

not survive competition over resources

C. characteristics that are acquired throughout an

organism’s life are not passed on to offspring

D. organisms in a changing environment must adapt to

acquire necessary traits and survive

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In an area of Indonesia where the ocean floor is littered with empty coconut shells, a species of octopus

has been filmed “walking” on two of its eight tentacles. The remaining six tentacles are wrapped

around its body. Scientists suspect that, with its tentacles arranged this way, the octopus resembles a

rolling coconut. Local predators, including sharks, seem not to notice the octopus as often when it

behaves in this manner.

4. Identify one adaptation of the Indonesian octopus. Explain how that adaptation helps the octopus

survive in its environment.

5. The Indonesian octopus’ unique method of locomotion (movement) the has lasted over many

generations due to

A. competition between octopuses and their predators

B. ecological succession in marine habitats

C. genetic adaptations being passed on to offspring

D. selective breeding of this octopus species

6. A population of turtles in a nearby lake consisted of turtles with plain brown shells and turtles with

patterned shells. After a drought killed many nearby plants, the turtles with the patterned shell

became much more visible to predators. Using Darwinian Theory, provide an explanation of how

this population could evolve over time.