Where do we treat sampling design, sample size, and the problem of unsampled populations within the study area? I thought this would be treated in lecture 3.

Maybe we can introduce the general idea here and then come back to it again in later lectures.  The sample design will vary depending on the question and analytical methods.  In addition, unsampled populations have an effect on the interpretation of the genetic data.  However, different spatial methods are more/less sensitive to missing sites (independent of use of genetic data or some other sort of data - networks being particularly sensitive to missing sites).  This would be a great area to point out the need for further research as the interaction between genetic sampling needs and spatial sampling needs is poorly understood. 

I agree with Melanie that a general sampling design recommendations are not possible because it depends on the question.  But it is true that I didn't introduce the topic at all and it is important and needs attention.  I'll think about how to introduce it and then others can continue the theme.

Lisette