natural selection€¦ · natural selection organism an individual animal, plant or single-celled...

Natural SelectionPresented by Kesler Science

1. How can you identify changes in genetic traits over several generations?

2. What are the differences between natural selection and selective breeding?

Essential Questions:

What are genetic traits?•Characteristics that are passed on to you (inherited) from you parents.

•Genes in your cells carry the information that determine your traits.

•Both plants and animals have inherited traits from their parents.

Natural Selection Video

© KeslerScience.com

These puppies came from the same parents, but have different traits.

https://drive.google.com/file/d/1CirnOaDszV3afD0fpP3B3kwkR1DRYB2u/view?usp=sharing

Natural Selection

OrganismAn individual animal,

plant or single-celled life form

EnvironmentThe surrounding or conditions

in which a person, animal or plant lives.


Charles Darwin•Born in England (1809-1882)•Famous for his work on natural selection

•Spent 5 years doing research on his ship the HMS Beagle

•Wrote “On the Origin of Species”, which was hugely controversial



https://drive.google.com/file/d/1TAH_yiuL3GYNZ47-rpxxrl1jrQpQ0zNG/view?usp=sharing

Natural Selection•The process whereby organisms better adapted to their environment tend to survive and produce more offspring.

•Favorable traits become more common over long periods of time.



https://drive.google.com/file/d/1ANDRhJDpuVCQDGpjIqcjhkMn2NHWsNHw/view?usp=sharing

Adaptations Video

•An adaptation is a body part or behavior that helps an animal survive in a particular environment.•Adaptations can help an animal breathe, catch food, or hide.•All animals are adapted to live in certain habitats.•Animals that cannot adapt will die out.•Happens through natural selection


https://drive.google.com/file/d/1OjuqWj6a8_kao2v5teCN31Z9eSiCfN34/view?usp=sharing

Adaptations

•All species have experienced adaptation and will continue to slowly adapt as the next generations are born.•We will identify certain species from each of these groups and the reasons for their success:–Mammals–Birds–Reptiles


Darwin’s Finches•Darwin studied finches on the Galapagos Islands.

•He theorized that 13 species had a common ancestor.

•The finches have developed distinctive beaks through the long-time process of adaptation.

•Each species of finches eat different types of food.

Adaptations Video


Medium ground finches vary in size and shape and make good subjects of study.

https://drive.google.com/file/d/1ilw3EfiMvC3gb2KTz7P7Ls0UwjB23LYI/view?usp=sharing

Adaptations

Other Bird Beaks• A cone-shaped bill found in many birds,

including finches, is good for cracking seeds.

• Thin, slender pointed beak are used to pick insects off of twigs and bark.

• Woodpecker have strong beaks which form a chisel for pecking holes in trees to get to the insects.

• Birds of prey have hooked beaks used to bite and tear their prey.

• Mallard duck’s bill are fringed to strain plants , seeds and small animals from mud and water.


Teeth Shape• The shape of an animal’s

teeth is related to its diet.• Herbivores, such as deer,

have many molars for chewing tough grass and plants.

• Carnivores, such as lions, have sharp canines to kill and tear meat.


Physical Adaptation

Physical Adaptation

Camouflage• Camouflage (use of color in a

surrounding)• The chameleon can change its

color to match its surroundings.


Mimicry• looking or sounding like

another living organism• The Viceroy butterfly uses

mimicry to look like the Monarch butterfly. Can you tell them apart?


Physical Adaptation

Chemical defenses (like venom, ink, sprays)• Skunk• Octopus• Snake


Physical Adaptation

Hibernation• inactivity (sleeplike state) during

winter.• During hibernation, the animal’s

temperature decreases, and its breathing & heart rate becomes very slow.


Behavioral Adaptations

Migration: • To move from one location to

another when the seasons change.

• Some organisms migrate short distances like frogs from pond to pond and sheep migrate from the mountain to valleys during winter.


Behavioral Adaptations

Quick Action – Natural Selection

Draw SomethingTalk to a partner about this scenario.Rat snakes are very similar except for the color variations. Some are green, black, and orange and even striped. If they come from a similar ancestor, why is there such a wide variation of colors?Fold a piece of paper into fourths. Based on its color quickly draw each rat snake in the environment in which it is likely to live. You have 5 minutes. Go!


Natural Selection

Selective Breeding video

•The process by which humans choose a plant or animal to breed based on specific traits.

•This is done by choosing which plants or animals will sexually reproduce to create the desired offspring.


https://www.youtube.com/watch?v=fHS-OY9XDZc

Natural Selection

Selective Breeding•Also called elective breeding

•Only occurs when humans intervene

•Adaptations happen over a shorter period of time than natural selection.


Natural Selection

•Engineered to contain foreign DNA that the organism could not obtain in traditional breeding.

•Usually used to introduce a beneficial trait

•Controversy as to whether GMO foods should be labeled as such


ExamplesCorn - insect resistance

Soybeans - herbicide tolerance

Rice - vitamin enrichment

Potatoes - virus resistance

GMOs – Genetically Modified Organisms

Quick Action – INB Template

Natural Selection INB Template

1. Cut out the Template along the solid line.

2. Glue tabs into your notebook.

3. The Template should open like windows.

4. Write your notes behind each flap.


Quick Action – Natural Selection

Say SomethingBrainstorm with your partner other plants and animals which have been selectively bred. Share the answers with the class.


Check for Understanding

Can you…1. Identify changes in genetric traits over

several generations?

2. Differentiate between natural selection and selective breeding?


natural selection€¦ · natural selection organism an individual animal, plant or single-celled...

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