Experimental field tests of Batesian mimicry in the swallowtail butterfly Papilio polytes

Abstract

The swallowtail butterfly Papilio polytes is known for its striking resemblance in wing pattern to the toxic butterfly Pachliopta aristolochiae and is a focal system for the study of mimicry evolution. Papilio polytes females are polymorphic in wing pattern, with mimetic and nonmimetic forms, while males are monomorphic and nonmimetic. Past work invokes selection for mimicry as the driving force behind wing pattern evolution in P. polytes. However, the mimetic relationship between P. polytes and P. aristolochiae is not well understood. In order to test the mimicry hypothesis, we constructed paper replicas of mimetic and nonmimetic P. polytes and P. aristolochiae, placed them in their natural habitat, and measured bird predation on replicas. In initial trials with stationary replicas and plasticine bodies, overall predation was low and we found no differences in predation between replica types. In later trials with replicas mounted on springs and with live mealworms standing in for the butterfly's body, we found less predation on mimetic P. polytes replicas compared to nonmimetic P. polytes replicas, consistent with the predator avoidance benefits of mimicry. While our results are mixed, they generally lend support to the mimicry hypothesis as well as the idea that behavioral differences between the sexes contributed to the evolution of sexually dimorphic mimicry.

Genetic switch in UV response of mimicry-related pale-yellow colors in Batesian mimic butterfly, Papilio polytes

“…Recently, it has been suggested that bird predators may not be able to distinguish the hind wing colors among mimetic and nonmimetic females (7). Meanwhile, field experiments have reported mimetic females to be less predatory than nonmimetic females (48). Figure 7 shows that the pale-yellow region, which is difficult to discern in the human eye, may be discriminated by predator birds and Papilio butterflies.…”

Spatial phylogenetics of butterflies in relation to environmental drivers and angiosperm diversity across North America

“…Butterflies (Papilionoidea) serve as an ideal study group for researchers and naturalists due to their diurnal activity, often vibrant and showy colors, and specialized larval host plant associations 7,8 . Not only are they the most collected and photographed insects 9 , but many species and clades of butterflies have become models for studying diverse ecological and evolutionary processes, such as Batesian and Müllerian mimicry (e.g., butterflies in the genus Heliconius [10][11][12][13] ), genetics and migration (e.g., butterflies in the genus Danaus ), and adaptation to agricultural systems (e.g., the common and widespread cabbage white, Pieris rapae 14 ). Butterflies also serve as pollinators and bioindicators of change and are one of the few insect groups where conservation agencies such as the IUCN have made at least initial assessments of species endangered status 15 .…”

What's in a band? The function of the color and banding pattern of the Banded Swallowtail

“…Papilio larvae (Prudic, Oliver, & Sperling, 2007;Tullberg, Merilaita, & Wiklund, 2005), little is known about the defensive strategies of Papilio adults beyond studies that have examined convergent wing pattern elements used in both Batesian and Müllerian mimicry rings (e.g., (Kitamura & Imafuku, 2015;Ohsaki, 1995;Palmer et al, 2018;Uésugi, 1996)).…”

“…Swallowtail butterflies (Lepidoptera: Papilionidae), in particular, are large and colorful species distributed worldwide that display a large diversity of wing color patterns (Aubert, Legal, Descimon, & Michel, ). While numerous studies have examined visual signals displayed by Papilio larvae (Prudic, Oliver, & Sperling, ; Tullberg, Merilaita, & Wiklund, ), little is known about the defensive strategies of Papilio adults beyond studies that have examined convergent wing pattern elements used in both Batesian and Müllerian mimicry rings (e.g., (Kitamura & Imafuku, ; Ohsaki, ; Palmer et al, ; Uésugi, )).…”

“…To test the protective benefit of both the transversal band as well as its blue‐green color, we constructed four different paper model variants of the Banded Swallowtail and tested how frequently each model got attacked by predators in the native habitat of the butterflies. Artificial paper models have been used in other studies involving predation and mate preferences to great effect, showing that these models are effective imitations of their real counterparts (Finkbeiner, Briscoe, & Reed, ; Ho, Schachat, Piel, & Monteiro, ; Palmer et al, ; Stevens, Hardman, & Stubbins, ; Wee & Monteiro, ). To test the protective benefit of the transversal band, we created a variant model where the continuous band was shifted to highlight the shape of the forewings and hindwings, rather than transverse them.…”