• Genetic Variation
• Mutations
  • Mutations are random
  • The Lederberg experiment
• Causes of mutations
  • Reviewing DNA
  • Types of mutations
  • Case study: sickle cell anemia
• Gene flow
  • Gene flow: details
• Sex and genetic shuffling
  • Sex and genetic shuffling: details
• Development
  • Types of developmental change
  • Ontogeny and phylogeny
  • Developmental constraints
  • Understanding complexity
  • Hox genes

Genetic Variation

Without genetic variation, some of the basic mechanisms of evolutionary change cannot operate.

There are three primary sources of genetic variation, which we will learn more about:

1. Mutations are changes in the DNA. A single mutation can have a large effect, but in many cases, evolutionary change is based on the accumulation of many mutations.


2. Gene flow is any movement of genes from one population to another and is an important source of genetic variation.


3. Sex can introduce new gene combinations into a population. This genetic shuffling is another important source of genetic variation.

Genetic shuffling is a source of variation.

	Lesson plans for teaching about variation

Mutations