Population Genetics and Molecular Evolution of Carrion-Associated Arthropods

A population is defined as a group of organisms of the same species that inhabit a particular geographic
area, but which are also capable of interbreeding with inhabitants of other geographic areas (Hartl and
Clark 1997). Therefore, this discussion should begin with the overall goal of defining a population of
carrion-frequenting insects. There are two classic models which would be appropriate to define populations
of carrion insects: the island model (Wright 1951) and the stepping stone model (Kimura and Weiss
1964). The island model assumes equal migration in and out of defined populations (=islands), whereas
the stepping stone model assumes a greater degree of exchange between neighboring populations in
which isolation by distance is observed. The actual population structure is likely a mixture of these two
models for carrion insects and is not well known or defined. This chapter will focus on describing the
population structure of carrion insects using existing molecular genetic techniques.