David B. Ritland

Erskine College · Department of Biology

Mimics should not exist without their models, yet often they do. In the system involving queen and viceroy butterflies, the viceroy is both mimic and co-model depending on the local abundance of the model, the queen. Here, we integrate population surveys, chemical analyses, and predator behavior assays to demonstrate how mimics may persist in locat...

In the eastern United States, the mimetic viceroy butterfly (Limenitis archippus) exhibits clinal variation in wing color, ranging from a tawny orange phenotype (L. a. archippus) in the N to a dark mahogany phenotype (L. a. floridensis) in Florida. Geographic distributions of these two subspecies are roughly coincident with the ranges of the vicero...

Viceroy butterflies (Limenitis archippus), long considered palatable mimics of distasteful danaine butterflies, have been shown in studies involving laboratoryreared specimens to be moderately unpalatable to avian predators. This implies that some viceroys are Mllerian co-mimics, rather than defenseless Batesian mimics, of danaines. Here, I further...

This study documents the existence of a food plant related palatability spectrum in Florida queen butterflies (Danaus gilippus). Abdomens of butterflies reared on four asclepiad food plants differed significantly in cardenolide content and palatability to a generalist avian predator (Red-winged Blackbird). However, unpalatability did not directly p...

Understanding the dynamics of defensive mimicry requires accurately characterizing the comparative palatability of putative models and mimics. The Florida viceroy butterfly (Limenitis archippus floridensis) is traditionally considered a palatable Batesian mimic of the purportedly distasteful Florida queen (Danaus gilippus berenice). I re-evaluated...

Queen butterflies (Danaus gilippus) are generally considered unpalatable to predators because they sequester and store toxic cardenolides from their larval food plants. However, a major queen food plant in Florida, the asclepiadaceous vineSarcostemma clausum, is shown here to be a very poor cardenolide source, and queens reared on this plant contai...

Limenitis archippus floridensis are conventionally characterized as palatable Batesian mimics of distateful Florida queens Danaus gilippus berenice, but recent experiments indicate that both butterflies are moderately distateful, suggesting they may be Mullerian comimics. Viceroys and queens offered as models to red-winged blackbird Agelaius phoeni...

Batesian and Müllerian mimicry relationships differ greatly in terms of selective pressures affecting the participants; hence, accurately characterizing a mimetic interaction is a crucial prerequisite to understanding the selective milieux of model, mimic, and predator. Florida viceroy butterflies (Limenitis archippus floridensis) are conventionall...

DEFENSIVE mimicry has long been a paradigm of adaptive evolution by natural selection1–3. Mimics, models and predators in a batesian mimicry system (unpalatable model, palatable mimic) exist in a very different selective milieu from those in a müllerian system (involving ≳2 unpalatable 'co-models')1,4–6. Consequently, the incorrect characterization...

Viceroy and red-spotted purple butterflies (Limenitis archippus and Limenitis arthemis astyanax) are broadly sympatric in the E USA, but very rarely interbreed in most areas. However, the butterflies hybridize relatively frequently in N Florida and S Georgia. This elevated hybridization is due to a unique combination of ecological and biogeographic...

The eastern tiger swallowtail butterfly, Papilio glaucus L., is comprised of three putative subspecies (P. g. canadensis R & J, P. g. glaucus L. and P. g. australis Maynard) which have a total range of approximately one billion hectares across the eastern half of the U. S. and nearly all of Canada (Fig. 1). Based upon multivariate discriminant anal...

The eastern tiger swallowtail butterfly, Papilio glaucus L. has been presumed to be comprised of three parapatric subspecies (P. g. canadensis R & J, across Canada and the northern U.S.; P. g. glaucus L., in the eastern half of the U.S.; and P. g. australis Maynard, in Florida). Populations from 27 north latitude in Florida to 50 north latitude in...