Research in my laboratory focuses on the ecology, evolution, biogeography, and conservation of butterflies and other organisms in Southeast Asia.
In terms of number of species, number of individuals, or sheer biomass, insects are the dominant multicellular organisms inhabiting the planet's terrestrial biomes. Of the 30+ orders of insects, the taxonomy, distribution, and habits of the Lepidoptera (butterflies and moths) are perhaps best characterized, making this group well suited to comparative analyses.
Current research focuses on several inter-related themes: 1) ButterflyNet: integrating butterfly traits, distributions and phylogenomics; 2) the phylogeography of butterflies and other organisms across the Indo-Australian Archipelago; 3) the role of Buddhism and other religions in biodiversity conservation in Southeast Asia; and 4) the evolution of mimicry in Elymnias butterflies (Nymphalidae: Satyrinae).
ButterflyNet: An integrative framework for comparative biology
The world is crawling with insects, many of which play crucial roles as pollinators, prey, mutualists, and critical components of ecosystem health. Despite their significance, insects remain understudied, imposing major limitations on our understanding of the patterns and processes in insect ecology and evolution. Butterflies are the exception, however, thanks to the efforts of centuries of collectors and enthusiasts who have appreciated their beauty and fascinating biology. More is known about their morphology, species distributions, behavior, and larval resources than any other insect group. However, this information needs to be synthesized, placed in an evolutionary context, and made available for research. This project will achieve these two goals by reconstructing the evolutionary history of the approximately 18,800 described species and assembling a database of biological information about each species using field guides, social media, collections, and other sources. All of this information will be made available to the public via a website with the goal of catalyzing synthetic research and comparative studies. In addition to public outreach and education, the members of the research team will train graduate students and postdoctoral researchers in systematics and bioinformatics.
This project will produce a set of online tools and databases for comparative studies of butterflies. At the heart of the project is the assembly of a molecular phylogeny incorporating all known butterfly species. A hierarchical approach will be used to reconstruct butterfly relationships. To create a robust backbone phylogeny, approximately 500 loci will be captured from a single exemplar species from within each of the ~1,800 genera using anchored enrichment prior to sequencing. Genetic data from public databases and from our own sequencing efforts will then be collected to include remaining known species and complete the phylogeny. Model-based inference will examine the complexity of speciation, extinction, biogeography, and trait evolution. Existing locality data will be assembled from museum collections, inventories, citizen science monitoring networks, and expert knowledge to model species distributions using the integrative Map of Life framework. Species trait data have already been assembled for some groups and regions, but this project will create a consistent, harmonized trait database while also closing major gaps to create a globally comprehensive compilation of trait data on species life history, interactions, ecology, and distributions. All of these data layers will be made available through the Map of Life online platform, thus delivering community vetted and curated data and tools to catalyze comparative research.
Espeland, M., Breinholt, J., Willmott, K.R., Warren, A.D., Vila, R., Toussaint, E.F.A., Maunsell, S.C., Aduse-Poku, K., Talavera, G., Eastwood, R., Jarzyna, M.A., Guralnick, R., Lohman, D.J., Pierce, N.E. & Kawahara, A.Y. 2018. A comprehensive and dated phylogenomic analysis of butterflies. Current Biology 28, 770-778. [Abstract]
Sahoo, R.K., Lohman, D.J., Wahlberg, N., Muller, C.J., Brattstrom, O., Collins, S.C., Peggie, D., Aduse-Poku, K. & Kodandaramaiah, U. 2018. Evolution of Hypolimnas butterflies (Nymphalidae): Out-of-Africa origin and Wolbachia-mediated introgression. Molecular Phylogenetics and Evolution 123, 50-58. [Abstract]
Phylogeography of Volant Animals in Southeast Asia
Studies of island biogeography and geographical vicariance have been instrumental in understanding the spatial distribution of biodiversity. The Indo-Australian Archipelago (IAA) in Southeast Asia comprises thousands of islands and is divided by one of the most abrupt biogeographical transitions in the world: Wallace's Line. It is perhaps for these reasons that Alfred R. Wallace's nineteenth century observations in the IAA stimulated the development of biogeography (or zoogeography) as a field of study. Until recently, pragmatic considerations hindered the application of methodological advances made in other regions to the study of biogeography in the IAA, despite its suitability as a natural laboratory. However, the past ten years have seen a flurry of renewed investigation, including a number of studies on the geology of the region and molecular phylogenetic investigations of the organisms that inhabit it.
I have investigated the phylogeography of several widespread butterfly and bird species found on many of the region's major land masses, and found that some populations of these "widespread" species are distinct enough to merit recognition as distinct species. In addition, I uncovered novel spatial patterns of genetic variation and Wolbachia infection across the IAA.
D.J. Lohman*, M. de Bruyn*, T. Page, K. von Rintelen, R. Hall, P. K. L. Ng, H.-T. Shih, G. C. Carvalho, & T. von Rintelen. 2011. Beyond Wallace's Line: genetics and geology inform biogeographical insights in the Indo-Australian Archipelago. Annual Review of Ecology, Evolution, and Systematics. In press. *joint first authors [TOC]
Lohman, D.J., K.K. Ingram, D.M. Prawiradilaga, K. Winker, F.H. Sheldon, R.G. Moyle, P.K.L. Ng, P.S. Ong, L.K. Wang, T.M. Braile, D. Astuti & R. Meier. 2010. Cryptic genetic diversity in "widespread" Southeast Asian bird species suggests that Philippine avian endemism is gravely underestimated. Biological Conservation 143: 1885-1890. [Abstract]
Sheldon, F.H., D.J. Lohman, H.C. Lim, F. Zou, S.M. Goodman, D.M. Prawiradilaga, K. Winker, T.M. Braile & R.G. Moyle. 2009. Phylogeography of the magpie-robin species comples (Aves: Turdidae: Copsychus) reveals a Philippine species and novel dispersal patterns in the Indian Ocean and S.E. Asia. Journal of Biogeography 36: 1070-1083. [Abstract]
Lohman, D.J., D. Peggie, N.E. Pierce & R. Meier. 2008. Phylogeography and genetic diversity of a widespread Old World butterfly, Lampides boeticus (Lepidoptera: Lycaenidae). BMC Evolutionary Biology 8: 301. [PDF] [Additional File]
Buddhism and biodiversity conservation in Southeast Asia
Curbing the loss of biodiversity and natural habitats is one of the planet's most pressing issues, and this problem is most acute in South and Southeast Asia. ropical rain forests are the most biologically diverse terrestrial ecosystems on Earth and are found almost exclusively in developing countries. Economic realities often force the destructive extraction of forest resources for short-term gain (e.g., timber and bush meat), thus destroying their long-term value.
Biologists have been sounding the alarm bells about the dangers of habitat loss and species extinction for many years, and it is now clear that the solutions to curbing the planet's current mass extinction event will be inherently non-biological. These remedies will require cross-disciplinary efforts, and E.O. Wilson has argued that public education campaigns work too slowly to curb the planet's biodiversity loss before it is too late. He argues that religion provides the most effective conduit to communicate conservation imperatives with a large audience in an expedient manner.
We are currently surveying the diveristy of several indicator taxa in Buddhist temples and surrounding areas in Thailand and in Sri Lanka to assess the role that these temples have played in biodiversity conservation. In tandem with these surveys, we are surveying monks and villagers who live in and around these temples to gauge their attitudes toward conservation and their role as environmental stewards.
Sodhi, N.S., T.M. Lee, C.H. Sekercioglu, E.L. Webb, D.M. Prawiradilaga, D.J. Lohman, N.E. Pierce, A.C. Diesmos, M. Rao & P.R. Ehrlich. 2010. Local people value environmental services provided by forested parks. Biodiversity and Conservation, 19: 1175-1188. [Abstract]
Evolution of Batesian mimicry in Elymnias butterflies (Nymphalidae: Satyrinae) (NSF DEB 1120380)
The butterfly genus Elymnias is a little-studied but species-rich group of Batesian mimics distributed primarily in Southeast Asia. Species vary in color, pattern, and size because different Elymnias species frequently mimic dramatically different models. Despite its potential as a system for studying mimicry, the evolution of wing patterns, and Southeast Asian biogeography, there has been virtually no biological research on this genus.
Using multiple, independent genetic loci, we and the laboratory of Shen-Horn Yen will generate a phylogenetic tree to address several key questions, including: 1) Have similar mimetic wing patterns evolved convergently? 2) Does the inferred timescale of diversification conform to hypotheses regarding the biogeographical history of Southeast Asia? 3) Have isolated islands been colonized more than once, or have their respective suites of endemic species diversified in situ? 4) Is divergence within a single landmass associated with shifts in mimetic color pattern?
Because of its species richness and extreme interspecific morphological diversity, Elymnias promises to be an unparalleled system for the study of wing pattern evolution and the evolution of morphological novelty.
Wei, C.-H., Lohman, D.J., Peggie, D. & Yen, S.-H. 2017. An illustrated checklist of the genus Elymnias Hubner, 1818 (Nymphalidae, Satyrinae). ZooKeys 676: 47-152. [Abstract]