Eastern/Canadian Tiger Swallowtails

[James J. Kruse]

On 15 Oct 1997, Semjase wrote:
> 
> Food plant differences?  Would you not need to determine if some insect
> apparently feeding on one species only in a particular environment will not
> also feed on a plant from a different genus which apparently is the
> food plant for the same insect in another environment.

Sure!  That is one possible scenario for testing food plant preferences of
an insect in different habitats. There are many examples of different
populations of the same species utilizing different food plant species.
The question of designating separate insect species comes in how distantly
related the plants are, as well as other evidence (such as interbreeding,
molecular sequence data, phenotypic differences, behavior, etc.).  In my
opinion, strong arguments for splitting species are arguments that include
a variety of evidence.

Cheers!
Jim Kruse
University of California at Berkeley
Dept. of Environ Sci, Policy and Mgmt.
Div. of Insect Biology
Sperling Lab
201 Wellman Hall
Berkeley, California, 94720-3113
(510) 642-5114/7410
http://www.CNR.Berkeley.EDU/sperlinglab/sperlinglab.html