Abstract
Platyphora leaf beetles form a vast group of tropical species each feeding on a restricted set of host plants and exhibiting bright coloration warning predators against their chemical protection. These beetles offer an exceptional opportunity for understanding the evolution of phytochemical sequestration. Indeed, qualitative studies of defensive secretions indicate that Platyphora species acquire toxicity via sequestration of plant secondary metabolites. All produce pentacyclic triterpene saponins from sequestered plant amyrins, but our analyses also indicate that many Platyphora species produce a dual chemical defence, that is, they are additionally protected by lycopsamine-type pyrolyzidine alkaloids that they also sequester from their host. This paper reports on the evolution of chemical defence and host affiliation in Platyphora leaf beetles as reconstructed on a molecular phylogeny of mitochondrial and nuclear DNA sequences. The analyses indicate that dual sequestration could be the key mechanistic means by which transitions among ecological specializations (i.e. restricted host-plant affiliations) are made possible.
Full Text
The Full Text of this article is available as a PDF (217.0 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Adler LS. Alkaloid Uptake Increases Fitness in a Hemiparasitic Plant via Reduced Herbivory and Increased Pollination. Am Nat. 2000 Jul;156(1):92–99. doi: 10.1086/303374. [DOI] [PubMed] [Google Scholar]
- Daly J. W., Garraffo H. M., Hall G. S., Cover J. F., Jr Absence of skin alkaloids in captive-raised Madagascan mantelline frogs (Mantella) and sequestration of dietary alkaloids. Toxicon. 1997 Jul;35(7):1131–1135. doi: 10.1016/s0041-0101(96)00212-7. [DOI] [PubMed] [Google Scholar]
- Eisner T., Hendry L. B., Peakall D. B., Meinwald J. 2,5-Dichlorophenol (from ingested herbicide?) in defensive secretion of grasshopper. Science. 1971 Apr 16;172(3980):277–278. doi: 10.1126/science.172.3980.277. [DOI] [PubMed] [Google Scholar]
- Eisner T., Meinwald J. The chemistry of sexual selection. Proc Natl Acad Sci U S A. 1995 Jan 3;92(1):50–55. doi: 10.1073/pnas.92.1.50. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hartmann T., Theuring C., Witte L., Pasteels J. M. Sequestration, metabolism and partial synthesis of tertiary pyrrolizidine alkaloids by the neotropical leaf-beetle Platyphora boucardi. Insect Biochem Mol Biol. 2001 Oct;31(11):1041–1056. doi: 10.1016/s0965-1748(01)00052-2. [DOI] [PubMed] [Google Scholar]
- Hasegawa M., Kishino H., Yano T. Dating of the human-ape splitting by a molecular clock of mitochondrial DNA. J Mol Evol. 1985;22(2):160–174. doi: 10.1007/BF02101694. [DOI] [PubMed] [Google Scholar]
- Kishino H., Hasegawa M. Evaluation of the maximum likelihood estimate of the evolutionary tree topologies from DNA sequence data, and the branching order in hominoidea. J Mol Evol. 1989 Aug;29(2):170–179. doi: 10.1007/BF02100115. [DOI] [PubMed] [Google Scholar]
- Mebs D. Toxicity in animals. Trends in evolution? Toxicon. 2001 Jan;39(1):87–96. doi: 10.1016/s0041-0101(00)00155-0. [DOI] [PubMed] [Google Scholar]
- Rausher M. D. Co-evolution and plant resistance to natural enemies. Nature. 2001 Jun 14;411(6839):857–864. doi: 10.1038/35081193. [DOI] [PubMed] [Google Scholar]
- Termonia A., Hsiao T. H., Pasteels J. M., Milinkovitch M. C. Feeding specialization and host-derived chemical defense in Chrysomeline leaf beetles did not lead to an evolutionary dead end. Proc Natl Acad Sci U S A. 2001 Mar 20;98(7):3909–3914. doi: 10.1073/pnas.061034598. [DOI] [PMC free article] [PubMed] [Google Scholar]