The connection between selection and adaptation.
What is an adaptation? http://en.wikipedia.org/wiki/Adaptation
1. Examples of problems: (To be discussed in class)
a. Fish and swords paper
b. Zebras and stripes
2. for homework A bit of History: Skim the following paper, paying particular attention to the problems Gould and Lewontin felt were plaguing evolutionary thinking at that time. Re-read the pages describing the blue bird experiment. The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme. STEPHEN JAY GOULD AND RICHARD C. LEWONTIN Link to a pdf download of this paper can be found on the schedule.
In class we will
a List the problems with the adaptationist programme as detailed by Gould and Lewontin.
b Critique the work on blue birds. What are some of the problems with the conclusions drawn from that work or how bad can a study of adaptation be?
c. Describe the solutions to the adaptationist programme proposed by Gould and Lewontin.
3. What now are the main factors limiting adaptation
http://evolution.berkeley.edu/evolibrary/article/misconcep_01
a. What are the limits to natural selection?
Note now we assume that other factors besides, mutation and sexual reproduction maintain variation.
b. List the reasons why “bad genes” persist?
4. A more in depth look at why adaptations are not perfect and difficult to study.
Read the limits to adaptation chapter from Stearns and Hoestra
In class, we will define and give reasons that the following can constrain selection and so affect the “perfection of adaptations.
a. Gene flow
b. Time lags
c. Trade off
d. Constraints
5. You should be familiar with the examples discussed in Stearns and Hoestra.
6. How to recognize adaptation
https://evolution.berkeley.edu/evolibrary/article/0_0_0/misconcep_06
a. How can you recognize an adaptation?
b. Describe two types of traits that are not adaptations.
A more in depth look at how to recognize “true adaptation”
Skim Chapter 10, from page 270 of Ridley.
c. How does he suggest adaptation should be studied? Are his methods in agreement with defining an adaptation as outlined on the Evo 101 website.
d. Describe the examples Ridley uses to illustrate why adaptations are not perfect.
e. How we can determine whether features are due to some constraint (such as a trade off) or an adaptation?
d. In this chapter Ridley introduces the idea of a morphospace and what it can tell us about adaptation. Be able to summarize his ideas.
e. Ridley elsewhere in his evolutionary text states, “Pluralism is appropriate for the study of evolution, not of adaptation. “
7. An important application of the modern study of adaptation.
http://evolution.berkeley.edu/evolibrary/article/conover_01
a. What was the effect of artificial selection on silversides and what significance does it have for commercial fishing.
b. Did Conover use any of ideas discussed by Ridley or regarding adaptation in general on the website evo101?
c. Was size the only trait that responded in Conover experiments to selection?
For those interested in Evolutionary medicine.