Mathematical quantification and statistical analysis of bombus (hymenoptera:apidae) dorsal color patterns

Evolution of Müllerian mimicry [similarity in appearance that confers protection to two or more organisms which are unpalatable or hazardous to a common predator (Wickler 1965)] has been an important topic in the study of evolutionary adaptation and visual signaling via color patterns since Fritz Müller first noticed it among Amazonian Heliconius butterflies. It has been documented in a wide variety of taxa, vertebrate and invertebrate alike, from birds to Chauliognathus beetles and bees. In bumble bees (Bombus), Müllerian mimicry has been hypothesized to occur in the form of color pattern complexes composed of often distantly related species. Understanding how these color patterns are developmentally and genetically regulated would contribute to an understanding of proximate mechanisms underlying natural selection and adaptation. However, this first requires a clear understanding of the color pattern elements themselves; that is, what are the actual units under genetic regulatory control? To date, bumble bee color patterns have been characterized relatively simply, minimizing pattern detail in the coding of individuals. To begin to decipher the mechanisms underlying the evolution of bumble bee mimicry, it is important to include the pattern details in the coding of individuals. This would allow insights into the true pattern, thus providing a basis for constructing a general quantitative scheme of the pattern elements and developing ground rules to explain how the pattern changes among individuals. The results of my coding and statistical analyses of the color patterns of 175 species of Bombus indicate that their color patterns are composed of developmental elements. The elements are dorsal regions that together comprise a model for the spatial arrangement and development of bumble bee color patterns. Morphological boundaries between metasomal tergites, thoracic lobes, and cuticular folds form the boundaries of these elements. Finally, the light colors white, yellow, orange, and grey appear more frequently than the dark colors red, tawny, brown and black in elements on the scutellum whereas dark colors are more frequent on the pronotum, scutum and metanotum. Dark and light colors were proportionally equally frequent in elements on tergite 4 of the metasoma.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Entomology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Cech, Juraj

Contributors dc:contributor

• Cameron, Sydney A.
• Rapti, Zoi

• Bumble bee
• Mullerian mimicry complex
• color pattern element

Statement dc:rights

• Copyright 2011 Juraj Cech

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/24242

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/24242