The following are excerpts from letters that I received from you. Here goes.

My name is Cherie from your Biology 215 class, I have problem with the

Following questions.

1. What is the difference between an organisms short-term responses to

environmental changes as opposed to the long term evolutionary changes?

This topic is covered on pages 1049 and 1050. A short-term response would be an animal moving out of the sun to cool down. In your long-term evolutionary changes, the whole population would change.

2. If play increases the probability that an organism will get injured, then what is the evolutionary use of play activities?

This topic is covered on page 1064 of your text. Everything has a cost and a benefit. If organisms do it, then the benefits must outweigh the cost. Be able to list the benefits to play.

3.How can one describe behavior in an evolutionary context?

Well this one is a bit more obtuse. A general discussion of various types of behavior is covered in the last half of the text. I would read page 1057. this is a biology class and everything has to be described in an evolutionary contex. (A hint would be to look at fitness)

4. What are boom and bust cycles? And how do they relate to an organisms

reproductive strategy?

Boom and bust cycles are when ecosystems experience periods of richness followed by periods of lacking. An example would be a wet summer where there are many plants and animals and a dry summer when very little plants grow. I would look at pages 1096 to 1101, especially the K and R selected traits.

5. How does the nonequilibrial model view communities as mosaics of patches

at different stages of succession?

Well read about succession first on page 1124, then read page 1121-2 then read about the Nonequilibrial model. Basically what scientists first thought were very stable climax communities in reality have a mosaic (many small patches) of different levels of succession going on at all times. So in essence the whole forest is in equilibrium, but each square meter of the forest floor is not.

6. Explain the effects of human populations on biodiversity?

You can read about the widespread effects that man has on the environment starting with page 1122. We are changing things, just by the fact that there are over 4 billion of us on this planet. Be able to describe in detail how we are effecting biodiversity? First off are we increasing it or decreasing it? How are we having that effect?