Natural Selection Info

Natural Selection Notes & Practice Questions

What do we need to know about how traits in a population change?

For instance, in this picture, what do you think will happen to the population of beetles over time?

You'll answer on the next screen...

Poll

What will happen to the population of beetles over time?

Eventually there will

• ... be no beetles left, since the birds will eat all of them.

• ... only be green since that is the bird's favorite.

• ... be more red beetles instead of green beetles.

• ... be a new color because the beetles will change to avoid being eaten.

Over many generations, the pressure from the birds will eventually change the variation of color for the beetles. More orange beetles will survive to reproduce, while more green won't be able to survive long enough to reproduce.

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Natural Selection says...

You should learn, by the end...

• I can tell the difference between natural selection & artificial selection

• I can list the criteria that is necessary for Natural Selection to happen

• I can identify different types of adaptations

• I can describe a specific way an organism has adapted to be successful in its environment

Add important information that should be added to your notes will be marked with a sticker that has a note pad and pen like this:

This can be hand written, or in a google doc if you want to type the info in.

Poll

Based on what you know so far,

Which of these examples show Natural Selection?

Pick as many as you think work.

• A gray tree frog and a green tree frog prefer different habitats

• A variety of bacteria is able to adapt to eat a new food source while another variety is not able to adapt

• Taking a tasty variety of apple and pollinating with a drought resistant variety of apple.

• Humans developing the enzyme to digest cow milk (lactose) while some cannot.

How come that was the answer?

A gray tree frog and a green tree frog prefer different habitats - this is speciation

Humans developing the enzyme to digest cow milk (lactose) while some cannot. - since this does not directly cause the person harm, this wouldn't be natural selection

Wrong Answer

A variety of bacteria is able to adapt to eat a new food source while another variety is not able to adapt. - One survives!

Taking a tasty variety of apple and pollinating with a drought resistant variety of apple. - This is a type of ARTIFICIAL selection.

Right Answer

What makes this different from artificial selection?

Artificial Selection

They will give the criteria for natural selection to happen - listen for these keys!

Natural Selection

Next Slide you'll watch a video. If it doesn't work, then there is a link to it in the agenda.

Multiple Choice

Natural Selection and Artificial Selection are...

• the same thing, they just use artificial traits or natural ones

• similar, they are based on evolution but one happens because of nature the other because of humans

• different, natural selection works because species naturally make decisions to change into something else. Artificial selection works because species are forced into changing into something else.

Artificial Selection

When humans, not nature decide...

In artificial selection, humans will put together different species based on traits that they want to see. This does not allow nature (for natural) to respond to predator/prey or ecosystems differences.

Multiple Select

Which of these were listed in the video as necessary for natural selection to occur? Check all that work.

• Limits on Population Growth

• Heritable Traits

• Humans selecting traits

• Variation in Population

1. Variation

2. Heredity

3. Limited Resources

4. Successful Traits

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4 Necessary Parts of Natural Selection

1. Variation - There are multiple finches present

2. Heredity - Not shown, assume they will pass on their traits.

3. Limited Resources - They all eat different food.

4. Successful Traits - Beak size allows them to successfully eat their food source.

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In the image, how do we see the four parts?

​P.S. Darwin is famous for his study of finches!

Natural Selection through ADAPTATION

• A feature or behavior that helps an organism survive

• Traits: neck length, beak shape

• The Point: organisms with favorable traits have a better chance of getting resources they need

Natural Selection through ADAPTATION

• The Porcupine has several traits that provide success when

  • Avoiding predators (quills)

  • Finding food (claws to climb trees)

  • Eating food (teeth that continue to grow after being worn down)

Multiple Choice

Quick trivia! Darwin is best known for his comparison of _______, but he also studied tortoises and iguanas

• piranhas

• monkeys

• finches

• butterflies

Types of Adaptations

Let's give specifics on the three types of Adaptations!

Structural Adaptations

• What? A PHYSICAL feature that developed over time that helps an organism survive

• Example: Narrow beak can probe in the sane for insects

• Example: Long legs can walk through deep snow

• Example: Sharp teeth for tearing apart prey

Dropdown

An _____________ helps an organism to move, reproduce, protect itself or find food.

Select answer

Camouflage - Structural Adaptation

• Linked to: a type of structural adaptation

• What? blending in with the environment

• How? Sneaking up on prey OR hiding from a predator

Multiple Choice

An example of a structural adaptation is...

• a turtle hatching on the beach

• The spikes on a porcupine fish

• a rabbit burrowing underground

• a viper biting when threatened

Mimicry

What? An organism resembling another organism.

How? By looking like the other organism, but not having the trait the organism can provide protection by "using" the other animal's features.

Open Ended

How would natural selection help support an organism that was a mimic?

Behavior Adaptions

How an organism acts can allow it a better chance to survive

Behavioral Adaptation

• Why? Certain behaviors give a better chance of survival.

• How?

  • Learned - through experience, organism gained adaptation

  • Instinctive - organism was born with the adaptation (innate). Can be reflex or instinct

Multiple Choice

Which is NOT an example of mimicry:

• The fur of an arctic fox turns white in winter to match the snow

• The tongue of an alligator snapping turtle looks like a worm, so he lures fish to his mouth

• A bad tasting butterfly & a good tasting butterfly have similar markings, so birds don't eat either kind

Multiple Choice

Which of these things could be a part of an oak toad's camouflage?

• It sews a different costume for the winter and the spring.
• The older toads teach their tadpoles how to turn invisible.
• Its brown skin blends in with the leaves and soil on the forest floor.
• Its bright colors show that it is the prince of toads.

Learned Behavior

• Animals are learning from their experiences.

• Learned cannot be passed on to the next generation like Instinctive

• Example: A lizard gets sick after eating a poisonous insect, the lizard avoids that type of insect in the future

Physiological Adaptations

Organism can perform special functions WITHIN the body

Physiological Adaptations

• Internal processes the help the organism survive

• Chemical = make poison for Snakes venom

• Internal Structures = Camel Humps

Multiple Choice

Which of the following describes a learned behavior in a dog?

• eating meat

• running fast

• digging holes

• guiding sheep

Multiple Choice

Smelts are fish that lay their eggs in the sand on beaches. When the eggs hatch, the babies know to go to the water. This is an example of:

• inherited trait
• learned behavior
• hibernation
• camouflage

Multiple Choice

Which of these is not an inherited trait?

• a bird building a nest
• a turtle burying its eggs
• a bear hibernating in winter
• a horse pulling a plow

Can you recall? We are at the end...

• I can tell the difference between natural selection & artificial selection

• I can list the criteria that is necessary for Natural Selection to happen

• I can identify different types of adaptations

• I can describe a specific way an organism has adapted to be successful in its environment

What's next?

• When you get your score on the next slide, you can try again if your score is less than 70%.

  • Full points for any score above 70%.

• Check Schoology!

  • Find a magazine with an article on an animal from the back table.