Wider applications of the simulator

Although the simulator depicts a particular and relatively obscure case of evolution, many of the lessons from it also apply to evolution in general. Mutations occur at random; their generation is usually independent of the environmental conditions and mutations can appear before a change to an environment in which they provide an advantage; and a new mutation can build on earlier mutations to produce complex phenotypes. All three of these factors are visible in the simulator.

Summary of points learnt

Hopefully, after reading the lessons and carrying out the simulator exercise you will have an understanding of the following things:

About Campylobacter jejuni:
  • It is found in the majority of chicken
  • It is the leading cause of food poisoning in the developed world
  • Occasionally, infection can be followed by a debilitating paralysis called Guillian-Barré syndrome
  • C. jejuni has a number of phase variable genes

About phase variation:
  • Phase variable genes contain hypermutable regions
  • This results in reversible, heritable switching on and off of phase variable genes
  • This switching can have important phenotypic consequences

Share this page: