Wednesday: February 22nd Class Agenda

1.) Class will divide into four groups. ALL four groups will read BOTH articles.

However, Groups 1 & 2 will be responsible for leading the group discussion on the article:

“Adaptation: The Case of Penguins” and sharing the answers to the article questions.

While Groups 3 &4 will be responsible for leading the group discussion on the article:

“Darwin and Natural Selection” and sharing the answers to the article questions.

(Please do not write on the articles, write on loose leaf paper. All responses to questions must be submitted before the end of class. Therefore, please pay close

attention when your peers are sharing article

Ms. Fisher 2/22/12

Objective For Today:

Through reading different articles on adaptation and natural

selection with your peers, you will further develop your understanding on natural

selection and know what factors play a role in this process. Today,

you will complete and submit corresponding worksheets that

go with these articles.

Articles Read on Evolution

• Adaptation: The Case of Penguins

• Darwin and Natural Selection

Article: “Adaptation the Case of Penguins”1.) What were some of the questions that naturalists were beginning to ask at the turn of the 19th century?

Why would a deity create parasites that would eat away at the insides of an organism, and what would the purpose be of creating a bird that could not fly? Why do certain things/patterns exist in nature? Hmm… Adaptation

2.)What is the difference between natural selection and adaptation?

Natural Selection is the mechanism that explains how things change; adaptation explains why they change.

Adaptation is based on the concept, organisms change over time as a result of natural selection. Adaptive evolution is driven by increased survivorship/increased reproductive success. This happens when individuals in a population gain an advantage because of special traits that they share in common. If trait is beneficial, over time the species will develop the trait because their offspring out reproduce others.

3.) Briefly explain how adaptive natural selection works by using an example but not the same as the example in this article.

http://www.youtube.com/watch?v=2k2UxiHREUM

4.) What are some of the factors that play a role in natural selection?Availability of food

Ex: Darwin’s Finches & beak sizes

Darwin was struck by the fact that birds were slightly different from one island to another. He

realized that the key to why this difference existed was connected with the fact that the various

species live in different kinds of environments.

Predator-prey relationshipsClimateEx #1: Penguins control their body temperature

in extreme climate conditions with an elaborate circulatory system. The arteries and veins in their

extremities are situated very close together so that they can exchange heat.

5.) Make a list of some penguin adaptations and how those adaptations help penguins survive.

Penguins control their body temperature in extreme climate conditions with an elaborate circulatory system. The arteries and veins in their extremities are situated very close together so that they can exchange heat.

Behavioral adaptation: they shiver to increase metabolic heat production and they pant/ expose their feet to get rid of excess heat.

6.) What are some adaptations that you possess that help you be successful in your environment?

We do not have wisdom teeth. This helps us be successful because we have a smaller jaw then the primitive hominid.

Darwin and Natural Selection Article

1.) If Charles Darwin did not invent the concept of evolution, what was his contribution to science?

Darwin carried out RESEARCH that documented evolution has occurred and then made the idea

acceptable for the general public.

2.) What was Darwin’s background and what did he study at the universities in Edinburgh and Cambridge?

At Edinburgh Darwin started as a medical student. Two years later he went to Cambridge to study theology. Here he became very interested in the scientific ideas of geologist Sedgwick and naturalist Henslow.

Galapagos Islands

Finches from the Galapagos Islands

Darwin’s Finches (movie) @time 6:15

http://www.youtube.com/watch?v=n3265bno2X0

3. Uniformitarianism is the geologic theory that states the forces that acted on the earth in the past continue to act on the earth today. What evidence do we have of this?

Fossils

Geological Evidence

5.) What is adaptive radiation?

Branching evolution in which different populations of species become reproductively isolated from each other by adapting to different ecological niches and eventually become separated species.

As Darwin observed on the Galapagos Islands. The finch species differed from each other in beak size and shape. Beak varieties were associated with diets based on different foods. He concluded that when the original South American finches reached the islands, they dispersed to different environments where they had to adapt to different conditions.

6.) What did Darwin mean by “decent with modification?”

Every population consists of individuals that are slightly different from one another. Those individuals having a variation that gives them an advantage in staying alive long enough to successfully reproduce are the ones that pass on their traits more frequently to the next generation.

7.) What is natural selection?

Process that results in the survival and reproductive success of individuals or groups best adjusted to their environment.

8.) What did Thomas Malthus contribute to our knowledge of populations?

He observed that human populations will double every 25 years unless they are kept in check by limits in food supply. Darwin realized that all plants and animals have the same potential, (to rapidly increase;) unless kept in check by predators.

9.) How do the peppered moths demonstrate natural selection?

During the 19th century pollution darkened the bark on trees. When moths landed on these trees, the dark colored ones were harder to spot by birds who ate them; subsequently, they more often lived long enough to reproduce. Over generations, the environment continued to favor darker moths. As a result, they progressively became more common.

http://www.youtube.com/watch?v=LyRA807djLc&feature=player_embedded#!

10.) What made Darwin decide to publish his ideas more than 25 years after his voyage?

He received an essay from a young British naturalist; Alfred Wallace. Wallace came upon the same explanation of evolution as he did. Therefore, Darwin published his book, on The Origin of Species.

Alfred Wallace

11.) What was missing from Darwin’s understanding of natural selection?

Recombination of

parental traits in

offspring which allows

for each generation to

have continued variation.

12.)What was Mendel’s

Contribution?

DNA,

genetic inheritance

13.) What evidence did Boucher de Perthes collect to show that humans had changed over time?

Perthes collected ancient stone tools. Since he found these artifacts in association with the bones of extinct animals, he concluded that they must have been made at the time that those animals lived.

Assessment:

Objective for Today:

Through reading different articles on adaptation and natural selection with

your peers, you will further develop your understanding on natural selection and

know what factors play a role in this process.

Availability of Food

Predator-prey relationship

Climate

Ms. Fisher 2/22/12