The concept that host plant favorites would be used for more rapid and/or efficient growth of the "locally adapted" individuals was tested in a preliminary way using the giant swallowtail butterfly, Papilio cresphontes. Populations feeding only on northern prickly ash, Zanthoxylum americanum (from Wisconsin), primarily (or exclusively) on hoptree, Ptelea trifoliata (in Ohio) and on lime prickly ash, Z. fagara, or Citrus, (in Florida) were compared on alternate hosts and on their actual local hosts under controlled environmental conditions. While the results with final instar larvae generally support the feeding specialization hypothesis with regard to more rapid and/or more efficient growth on local food plant favorites, we are hesitant to extrapolate these results to the species as a whole for several reasons dis- cussed herein.
Scriber, J. Mark and Dowell, Robert V.
"Host Plant Suitability and a Test of the Feeding Specialization Hypothesis Using Papilio Cresphontes (Lepidoptera: Papilionidae),"
The Great Lakes Entomologist: Vol. 24
, Article 5.
Available at: http://scholar.valpo.edu/tgle/vol24/iss1/5