ZOOL 304
Class Notes
Chapter 6
Text reading: Chapter 6.
- Introduction
- Comment on text Chapter 6
Introduction
Adaptive evolution is genetic change in a population due to the correlation of hereditary variation with variation in reproductive success. Understanding adaptive evolution involves understanding all aspects of this process.
The nature of genetic change in populations is understood through the principles of population genetics and quantitative genetics. In these disciplines, the correlation between genetic variation and fitness variation is taken as given and is represented abstractly by selection coefficients (in population genetics ) or by response to selection (in quantitative genetics). This understanding forms the core of modern evolutionary theory, as introduced in Chapters 3, 4 and 5.
However, neither population genetics nor quantitative genetics explains why the correlation between hereditary variation and variation in reproductive success exists in the first place. This correlation emerges from a set of causal relationships between genetic differences and trait differences (introduced in Chapter 6), and a set of causal relationships between trait differences and fitness differences (considered broadly in Chapter 8). Together these relationships form a causal loop which yields ongoing adaptive evolution.
Chapter 6 discusses some of the principles which relate genetic information to organismal form and function. At least for Spring term of 2003, this topic will be omitted from ZOOL 304.
Notes for chapter 1 / 2 / 3 / 4 / 5 / 6 / 7 / 8 / 9 / 10 / 11 / 12 / 13 / 14 / 15 / 16 / 17
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