Natural Selection Activity Ap Biology Essay

TIME:
One teaching period (40-50 minutes)

TEACHING PREPARATION & STRATEGY:
1. This is best done in conjunction with your introduction to natural selection. It could probably work as well before students study it, or after. Vary with different classes to see which works best. Let us know your conclusions.



2. Separate the cards into their 4 suits (all 13 cards for each suit), and place each set of 13 cards into a separate numbered envelope. Be sure you have enough sets for each team (of 2- 4). These sets can be re-used in subsequent periods.
3. Run off copies of instructions and discussion questions if desired (one set per team is fine).
4. Have scratch paper handy.

PROCEDURE:
1. Divide the class into teams (of 2-4 each)
2. Each team has at least a "recorder" and a "player".
3. The Recorder records the number of rounds played (tally mark for each)
4. Player(s): serve as shuffler, card handler, and/or observer.
5. You may introduce the "game" in various ways, depending on their background and experience.

 - a. Simply as "an interesting game" .. to be discussed as to its significance afterwards.
- b. Announce that this is a "Natural Selection" simulation.
- c. Point out that there is often confusion about natural selection being a random process, and many wonder how such a random process could produce useful complex structures in a reasonable time period.
- d. Let them read the Background and Instructions, do the activity, then be prepared to discuss the questions in class.

6. Point out that Odd-Numbered teams will follow procedure A, and Even-Numbered teams must do procedure B. When a team achieves the goal (full sequence ace-to-king), the recorder reports the number of rounds taken to do it. One of the players thoroughly shuffles the cards, returns them to the envelope, and hands it in to the teacher. That team goes to work on the questions, preparing for class discussion.

7. About 5-10 minutes after the last B team has turned in its number of rounds played, call a halt to all remaining team activity. Each remaining set of cards is thoroughly shuffled, returned to its envelope, and this is handed in to the teacher. Display the number of rounds taken by each team, and begin to discuss the questions. For a copy of reasonable responses to the Discussion questions, email your request from your school email address to the Webmaster. Specify this lesson.

8. Above all, it is critical that students come away with a clear understanding that cumulative natural selection (as Darwin postulated) is a primary source for all new characteristics that have arisen since life began. The cumulative aspect of this is critical partly to show how it increases probabilities for increasingly complex or new combinations in relatively short time spans. And... selection is NOT a random process.
The other function of the cumulative feature is that it builds upon already-successful structures. This has also been called "successive selection of adaptive combinations." It's this cumulative feature which is key to its creative potential. Natural selection is often assumed (incorrectly) to be simply an elimination process, removing all the ill-adapted mutations as they appear. However, especially with details of molecular structures and processes being continuously revealed and understood in diverse species, we have a growing body of observations most easily explained by descent with modification (= evolution), occurring as a result of cumulative natural selection.

EPILOG AND COMMENTS:
1. It is important that no religious group (or even "creationists", and certainly no students) be ridiculed for their beliefs that may claim that evolution is wrong. Simply make the general true statement that there are many who misunderstand and may innocently misrepresent evolution, and the point of this exercise is to clearly demonstrate what natural selection IS, and what it is NOT, primarily to clear up the widely held misconceptions. If asked where the misconceptions came from, explain that lots of new ideas can be misunderstood, and if someone writes articles presenting a misconception, many people accept it without questioning, and innocently repeat the ideas to others. This is especially true if the misconception seems to strengthen one's deeply held beliefs (example of confirmation bias).

2. For example, you can mention that some may have heard that an organ such as an eye or an enzyme system could not have arisen by pure chance within a reasonable length of time, therefore evolution could not produce such complex structures or processes, much less complete organisms. The premise is correct, but the conclusion is wrong, because the basic assumption is wrong: evolutionary biology does NOT make this claim. Rather, it claims that such structures and processes arose largely by the accumulation of favorable mutations through the process of cumulative natural selection. Mutation is a chance process (within limits); selection is a cumulative NON-CHANCE process. As the card game simulation showed, evolution by cumulative selection of favorable mutations (those that contribute to survival) is a relatively rapid process.

3. If you want to take an even closer look at the evolution of the eye, click here for web sites that do that. Note that there are also many web sites which attempt to discredit these evolutionary explanations for eye evolution, but an element common to all is their total disregard for cumulative selection and how this alone increases probabilities profoundly.

TRY THIS ENGAGING INTRODUCTORY STORY
share it with you here

PBS Evolution seriesfreeTeachers Guide

4.b. Another teacher tries this (above) and adds the following:
I used the activity in 5 classes of Pre-AP Biology today. My students are all Gifted and Talented/Vanguard students so my attempt at the vague intro suggested by another teacher [above] was soon clear on who/what we were discussing. I tried to change it up a bit and call the guy “Chuck” and spin it a bit more comedically and that seemed to keep their interest. I used this as the very first hands-on activity to introduce Natural Selection and will start with content tomorrow [Feb. 12, "Chuck's" birthday].

The activity itself was great and really challenged the GT students to keep going, even if it felt futile. They were more interested to know if any other groups finished (competitive as they are). The only changes I made to the activity were more procedural:
1.       I found that modeling how to shuffle and pretending to be Group A and then Group B really clarified what they were supposed to do with the cards. My students tend to read way too much into directions instead of just the basics so a quick run through as if I was each group was enough to clarify the first time.
2.       I had Group B shuffle and look until they found the ace. The directions suggest they can start with a “7” and go from there but that seemed to throw them off because the text just before it asks if the top card was an ace.

Overall, the students were engaged throughout the whole activity and the group discussion following the activity went well (thanks again for the suggested answers to the questions!).
Houston, Texas

EXTENSIONS & VARIATIONS:
1. Further evidence that species are the product of long term accumulated modifications can be found in the existence of pseudogenes (non functional DNA sequences that are nearly identical to certain functional genes). An excellent series of lessons available on this site enables students to experience the existence of pseudogenes by exploring the production of vitamin C in selected organisms and how this points to common ancestry. Take a look at the Pseudogene Suite. The existence of pseudogenes also suggests that natural selection provides a more parsimonious explanation for the origin of species than does "intelligent design", anaother name for what is essentially "scientific creationism", an excellent example of a pseudoscience.

2. In conjunction with this lesson, provide your students with a natural selection simulation experience which takes them through at least a few generations of selection, e.g. "The Chips Are Down" natural selection lesson, or "Natural Selection of Bean Hunters" .

3. Take a look at the handy summary: "Comparing Evolution Mechanisms" near the bottom of the "Introduction to Evolution" page. Darwin's and Lamarck's essential elements are compared, and a few common misconceptions are clarified. Scroll down to download the PDF file of this information.

4. Also consider doing Chaos & Order: Non-Random vs Random lesson.. This is a natural companion to the cumulative nature of natural selection: these are two important features of natural selection that are seldom addressed.

5. STEM: PRACTICAL APPLICATIONS of NATURAL SELECTION

 

REFERENCES:
1. In addition to those listed in the article by Dr. Heim:
Dawkins, Richard. 1996. Climbing Mount Improbable. New York: Norton & Co. See especially chapter 5.
A Critical Review of Behe's Darwin's Black Box and the flaws in the author's "irreducible complexity" ideas. Includes examples of complex structures and molecular processes whose probable evolutionary sequence by cumulative selection have been figured out.

 ATTRIBUTION

Some of the ideas in this lesson may have been adapted from earlier, unacknowledged sources without our knowledge. If the reader believes this to be the case, please let us know, and appropriate corrections will be made. Thanks.

Original article: "Natural Selection Among Playing Cards" by Werner G. Heim, in the April 2002 issue of The American Biology Teacher, vol. 64, no. 4, pages 276-278. Dr. Heim is Professor Emeritus of Biology, Department of Biology, The Colorado College, 14 East Cache La Poudre, Colorado Springs, Colorado 80903-3294; E-mail: wheim@coloradocollege.edu

Lesson adapted for ENSIweb lesson by Larry Flammer, September 2002, with kind permission of NABT and the author.

Some updating and correcting: 6 April 2007.

ГЛАВА 24 Дэвид Беккер стоял в телефонной будке на противоположной стороне улицы, прямо напротив городской больницы, откуда его только что выставили за причинение беспокойства пациенту под номером 104, месье Клушару.

Все внезапно осложнилось, пошло совсем не так, как он рассчитывал. Мелкая любезность, которую он оказал Стратмору, забрав личные вещи Танкадо, вылилась в поиски таинственного кольца, как в известной игре, где нужно находить спрятанные предметы.

Дэвид только что позвонил Стратмору и рассказал о немецком туристе.

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