2/27 Biology update and homework due 3/13

Hi folks,

First off NO CLASS NEXT WEEK.  Next week is spring break for us so there won't be class.  Enjoy the time off (or…take the time to do some extra studying…your call.  :)   )

This week we took a bit of time to review some of our most recent quiz questions.  It looks like we are getting a good handle on the evolution concepts but I wanted to make sure a few key points are clear.   

With that in mind, we also did a very interesting lab today.  Using a paper airplane design as a model bird, we explored how random mutations and natural selection could slowly evolve a species into one that is more fit for its environment.

For homework this week please answer the following questions about today's lab.  I've included data from each of my biology classes so you can see a larger sample size.  The write up for the lab is on page 314 and 315 in your book if you wish to refer to it.

1. What was "selecting" for the successful bird?

2.  What represented the "mutations". 

3.  In each trial you used a "clone" of the previous generation.  Why is the term clone appropriate?

4.  If you consider that all groups started with the same species of bird, would you say that by the end of the lab each group would have created a different species from each other group or not?  Defend your answer.

5.  Is this lab an example of disruptive, directive, or stabilizing selection?  (May need to use your notes or the book if you don't recall these terms.)  Why do you think so?

6.  Did each generation always progress?  In other words, did each generation get a farther flyer?

7.  How does this lab represent natural selection?

8.  In a way, there were three traits that were adapting in order to create a better flyer.  Which three traits were involved in this model?

10.  Describe two aspects of this investigation that model evolution of biological organisms.

11.  How might this lab help explain the observations Darwin made about finches on the Galapagos Islands?

12.  How would you say the term "fitness" is represented in this lab?

13.  Using this lab, give an example of each of Darwin's four postulates (DOGS).  (Hint: one of them actually is not represented in this lab.)

14.  How would you alter the lab if the environment this population of birds was in was very very windy, so that if a bird left the ground it may be blown out to sea?  What would you change to model this new scenario.