Sampling species abundance distributions: Resolving the veil-line debate

Prestonʹs classic work on the theory of species abundance distributions (SADs) in ecology has been challenged by Dewdney. Dewdney contends that Prestonʹs veil-line concept, relating to the shape of sample SADs, is flawed. Here, I show that Prestonʹs and Dewdneyʹs theories can be reconciled by considering the differing mathematical properties of the sampling process on logarithmic (Preston) versus linear (Dewdney) abundance scales. I also derive several related results and show, importantly, that one cannot reject the log-normal distribution as a plausible SAD based only on sampling arguments, as Dewdney and others have done.