Evolution Unit

1. What is Evolution?

2. How does it work?

3. What is the evidence for it?

4. How does it connect to genetics?

clothespin beakSpoon beaker tong

Snack Clip"

Salad tong

hair clip

curling pin"

Write a paragraph about a time where someone asked you or told you to change.....and you did. Then, write about a time where someone asked you or told you to change....and you did not. (What were the consequences in both situations?

What is Evolution?

Evolution is changes to a species over time.

Organisms evolve due to changes in the environment. These changes in the environment cause the organisms to adapt (behavior or mutation) or die out (extinction).

The changes in the environment happen naturally (natural disaster or scarcity of food) or artificially (impact of humans).

Competition in an environment is what drives evolution.

Examples of natural selection:

Simulation 1: There are four organisms in an environment. Each needs one cheerio to survive. The food supply is four cheerios. Everyone is happy! A new organism moves into the area, but there now there are only four cheerios for five organisms. What will happen?

Example 2: Musical chairs......7 chairs, but 8 people!

Simulation 2: 2 male organisms competing for one female to reproduce. One will win her and the other will either have to find a less desirable mate or not continute his species.

Survival of the fittest!!! Survival of the fitter!

Cheerio lab will help answer the questions:

What is evolution and how does it work?

We will learn how organisms have to be better adapted to the environment when resources are limited.

How does evolution work?

change demandedby the environment

you

change (consequences)

don't change (consequences)

How does evolution work in wolves?

humans and trash wild (hate to hunt for food)

tamer (tolerated humans and ate food)

wolves

Evolution Movie Write-Up

1) How does evolution work in dogs?

2) What role did humans have in their development?

3) How are changes in traits carried on genes?

4) How can changes in traits result in changes in behavior?

What is the evidence for evolution?I. Fossil Records- a collection of fossils can tell the story of evolution.

II. Similarities in organism's physical and anatomical structures- structures can tell us about a species having a common ancestry

A) Homologous Structures- same parts, different functions (e.g. human arm and whale fin)

B) Analogous Structures- same functions, different parts (e.g. bird wing and fly wing)

C) Vestigial Structures- parts that used to have a function, but that function isn't needed anymore, so the part is not used. (Ex:

tailbone and appendix)

Theories of Evolution

1) Lamarka. if you use it, you get more of it and if you don't

use it, you lose it.

b. thought that organisms made adjustments to changes in the environment and then these adjustments would be passed on to offspring. (ex: reading)

c. did not know a lot about genetics

2) Darwin

a. natural selection

b. survival of the fittest (most adapted)

c. pass on adaptation to offspring

Modern Examples of Evolution

1. Drug Resistant Bacteria- antibiotics (pencillin)

2. Peppered Moth

How does evolution relate to genetics?

1) Species can adapt to changes in the environment by mutations in the genetic code and then these mutations are passed on to offspring.

2) Organisms that are closely related to each other have very similar DNA (ex: different breeds of dogs)

3) DNA analysis can be used to demonstrate common ancestry and evolution

4) Genetic evidence is the most valid form of proof for evolution