Masashi Yoshimura, Staff Scientist


I am interested in morphological evolution and systematics of ants based on comparative studies using males. Male ants are unexplored resource for understanding ants’ evolution and diversity, because most part of our current morphological knowledge for ants is based on the workers, which are non-reproductive females. Detailed morphological examinations of male ants and male-female comparative studies following recent molecular phylogenetic studies will provide new remarkable characters that demonstrate their morphological evolution.

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Georg Fischer, Postdoctoral Researcher

I am interested in ant community ecology as well as biogeographic and evolutionary patterns, especially of diverse tropical ant assemblages. A big part of my work in the last years and during my current project is the taxonomy, biogeography and evolution of the extremely species rich and ecologically highly diverse genus Pheidole, and recently also of the genus Carebara, both of which are characterized by a pronounced worker differentiation into di- and polymorphic subcastes respectively. In both genera there are several cases of species which don’t follow the general “rules” and either developed an additional worker subcaste (often named supersoldiers or supermajors) or lost one or more of their worker castes. I’d like to find out more about their respective ecologies and possible underlying evolutionary patterns.

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Eli Sarnat, Taxonomist-at-Large


My current research focuses on better understanding the diversity of Pacific island ant faunas and preventing the spread of invasive ant species across the globe. I study the evolution, systematics and biogeography of Pacific ants, especially those of the Fijian archipelago. I am also developing identification guides to invasive, introduced and commonly intercepted ant species to help researchers, quarantine personnel and conservationists prevent their spread. I work on projects remotely from my solar-powered cybertaxomony lab in the Klamath-Sikisiyou mountains of Northern California.


Cong Liu, Graduate Student

I spent three years in the tropical forest (Xishuangbanna, China) to study fig and fig wasp mutualism for my Master’s degree. My research at that time was to answer how and why the body size of fig wasps evolved and its implications for stability in a fig-pollinator mutualism. I also did a lot of works about the behavior and pollination biology of fig wasps. During the time in the tropical forest, I had developed a broad interest in ecology, such as entomological ecology, evolutionary ecology, conservation, biogeography, plant-animal interaction and biodiversity. So after I got my master’s degree from the Chinese Academy of Sciences, I decided to pursue my Ph.D degree in OIST. I enjoy the peaceful life here where people live in great harmony. OIST is a paradise for researchers where my ideas can incubate. Since joining the lab I have been working on ant cuticular hydrocarbons, ant community ecology in China, and the optical properties of ant cuticle.

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Masako Ogasawara, Research Technician


New to the world of ants, I am now learning about their biology. In Arilab I help processing the field samples and curating the ant collection. So far, I have had the chance to work with ants from different places around the world including Fiji islands, China and Okinawa! I am originally from Yokohama in Japan, but have lived in Okinawa for thirteen years where I enjoy every day the beautiful landscapes and nature of the island.

Nitish Narula, Research Computing Technician

I recently graduated from New Mexico State University with an MS in Biology. While there, I was involved in an avian phylogenomic project using insertion-deletion characters. My academic background is in evolutionary biology, genomics, bioinformatics, and applied statistics. In the Economo lab, I work as a computing technician assisting the lab in its computational needs.


Julia Janicki, Computing Technician


I received my M.S. in Entomology from UW-Madison, focusing on beetle taxonomy and biodiversity; specifically, I conducted a survey of the primitive weevils in Wisconsin. While taking on my project, I became interested in ways of visualizing data and took up skills in interactive mapping and front-end web development. As part of my M.S. project I created an interactive web mapping application for my survey results. With a team, I have recently built that visualizes the GABI database. My interests include biodiversity, conservation, evolutionary biology, taxonomy, cartography, data visualization, and web development.


Kenneth Dudley, GIS & Remote Sensing Technician

I graduated from the University of Utah with undergraduate degrees in Geography, Japanese, and Environmental & Sustainability Studies. I then continued my studies in geography and obtained an MS in Geography at the University of Utah. My primary area of interest is remote sensing of vegetation using multispectral and hyperspectral datasets. I work with GIS and remote sensing datasets to study and model environmental phenomena. In my free time I create and update tools to improve processing of remote sensed images using Python and ENVI/IDL.


Chisa Oshiro, Research Administrator


I was born in Okinawa but went to the United States to get a Master’s degree in American Literature with a focus on environmental literature. I wrote about the relationship between humans and nature by comparing the thoughts of great authors, artists, and architects. I also wrote about culture, language, and identity. The mixture of these ideas gave me the desire to return to Okinawa with the goals of spreading public education, preserving nature, and improving self-reliant economic development in Okinawa. I am overjoyed to have the opportunity to pursue these goals at OIST by using my past administrative experience to help the everyday operations of Arilab’s research.

Patricia Wepfer, PhD Student

I am generally interested in spatial patterns of biodiversity and evolution in the context of biophysical/-geographical processes. In my PhD project I aim to understand diversification and connectivity in hard corals on the example of the genus Galaxea (Oculinidae). For this I collect fresh samples and museum specimens from all their Indo-Pacific distribution range and analyze them with population genomic tools.
Other interests and previous projects include traditional botany, community ecology of ants and the variation in the symbiotic community in corals.


Nick Friedman, Postdoctoral Researcher


I am interested in the origins of biodiversity: how did we get so many species, and how did they get to be so different from one another? My research focuses primarily on trait evolution, examining the history of evolutionary change, how trait physiological has changed, and what selective context explains the cause of that change. I use the Australian honeyeaters and allies (Meliphagoidae) as a model clade to study the evolution of morphology and elaborate plumage coloration in birds. I want to understand how these traits are driven by natural and sexual selection in different ways across the various biomes of Australia and Papua New Guinea. In the Biodiversity and Biocomplexity Unit at OIST, I also use these phylogenetic comparative approaches to explore patterns and mechanisms of diversification and disparification in ants.


Clive Darwell, Postdoctoral Researcher

I am interested in how biodiversity is structured within ecosystems and what patterns and processes can be identified to describe and explain it, and more specifically, in how ecological interactions in conjunction with the evolutionary and biogeographical histories of species determine the composition, structure and function of biodiversity. I am also interested in how these relationships are maintained or modified according to both environmental factors (e.g., climate change) and additional biotic pressures (e.g., in the face of competition, predation, or parasitism). Before moving on to ants, I have studied the fig-wasp and yucca-moth obligate mutualism systems in previous research.


Takuma Yoshida, Technician


I studied the systematics of the parasitoid wasp family Ichneumonidae as part of my graduation thesis at the laboratory of Systematic Entomology, Hokkaido University. In order to get an idea of their diversity on a global scale, I have been putting a lot of effort into collecting, making and managing specimens, which also led me to become interested in collection management. I have experience as a curation assistant at the Hokkaido University Museum and Muséum National d’Histoire Naturelle of Paris and have been learning how to manage insect collections. At OIST I am involved in the OKEON (OKinwa Environment Observation Network) project. My task is to manage insect specimens collected for this project. I train para-taxonomists and guide them to collect and sort insect samples from twenty-four sampling sites set up around Okinawa.

Francisco Hita Garcia, Staff Scientist

I am a systematicist interested in the biodiversity and evolution of ants on different spatial and organismal scales. My aim is to explore and document nature in order to increase our understanding of the biological patterns and processes that have shaped our planet’s biodiversity. My research broadly encompasses taxonomy, phylogenetics, and biogeography of ants. The backbone of my research is the revisionary taxonomy of a variety of ant genera based on an integrative approach combining traditional comparative morphology with modern techniques, such as phylogenomics and 3D modelling based on x-ray micro computed tomography. One of my current projects focuses on the evolution and biogeography of the African/Malagasy genus Terataner using next generation sequencing. The other large project I work on is the global phylogenomic study of the hyperdiverse genus Tetramorium. I want to reconstruct the evolutionary history of the genus to determine which underlying macroevolutionary and macroecological processes have led to its global success.


Dan Warren, Visiting Researcher

I have broad interests in evolution, ecology, conservation, and animal behavior. My primary research program focuses on the evolution of species’ environmental tolerances and spatial distributions, with frequent detours into conservation-oriented empirical studies. I also maintain active research programs in phylogenetic methods and theory, as well as the neuroecology of marine fishes. My work includes both basic and applied research, with a particular focus on developing quantitative methods. I am an author of several popular software packages for conducting evolutionary and ecological analyses, including Converge, AWTY, ENMTools, and RWTY. In my spare time I make odd little audio art things and compose music for documentaries.

Mayuko Suwabe, Technician

Until recently I have worked at the social educational facility as a coordinator of outdoor education for 8 years. I had taught some nature activities to school students and made cooperative relationships with the local communities. Before that, I studied the community ecology of ants in University of the Ryukyus, Okinawa. My research focused on the effects of forest disturbance on invasion of alien ants and distribution of native ants in the Yanbaru forest. At OIST, I am working as a research technician involved in OKEON (Okinawa Environment Observation Network) project and the fire ant management project of Okinawa.

Nao Takashina,Postdoctoral Researcher

I am a theoretical ecologist primary interested in ecosystem management and conservation biology where trade-offs between ecological and socioeconomic benefits are widely observed in practice. To address this dilemma, I try to develop frameworks for decision-making processes for better management and conservation actions. My ongoing projects include developing ecological sampling theory and methods for population estimation to provide required (not necessarily be perfect) ecosystem information at a minimal cost and time, as well as understanding effect of marine protected areas from a broad point of view (e.g., their optimal size and spatial structure, and impact on competition between fishers in terms of game theory).

Yuka Suzuki, PhD Student

I am interested in theoretical and computational study in biology. I used computer simulation to study protein conformation change while an undergraduate. I have been specifically excited about network concept in biology, and generally interested in ecology too, so I have decided to work on networks in ecology by applying network theory to them. I have analyzed habitat distribution networks of ants. I am currently studying larval dispersal connectivities among coral reefs using both theoretical and realistic connectivity networks.

Adam Khalife, Intern (Fall-Spring) 2017

I recently graduated from the Ecole Normale Supérieure de Lyon in France with a major interest in Ecology, Evolution and Behaviour. I have just started a PhD in the Université Pierre et Marie Curie, Paris, France, that focuses on the link between the evolution of skeletomuscular morphology and behavioural repertoire in ants. One of my goals is to understand the mechanisms underlying the legendary strength of worker ants. I developed my freeware workflow to analyse microCT data, from segmentation to quick visualization. I am visiting the Economo Unit for six months to learn more about the technical aspect of microCT, study the anatomical differences between ant workers and queens, and get involved in a big project of the unit about morphological evolution in Madagascar ants using geometric morphometry (landmarking).

Sam Ross, Visiting Research Student

I recently started a PhD with Ian Donohue at Trinity College Dublin on the impacts of global change on ecological stability. In the Economo Unit, I’ll be working with data collected as part of the OKEON-churamori project to test whether land-use and/or environmental variables affect the temporal dynamics of different species. Overall, I’m aiming to establish whether and how community regulation differs across Okinawa, and what this means for the temporal stability of the island’s bird and insect communities.

Evropi Toulkeridou, PhD Rotation Student

I have a degree in mathematics and a MSc in theoretical informatics, both at the Aristotle University of Thessaloniki, Greece. I have joined OIST as a PhD student since last year study computational biology. My current research interest is on computer vision and, more specifically, its application for the analysis of microCT data.

Julian Katzke, PhD Rotation Student

Insects are incredibly diverse and so are their ways of life. During my master’s in Bonn, I realized that these complexities span out into deep time I want to think of and answer questions on how insects reached this astounding level of diversity and what pathways they took in their evolutionary history. Ants are particularly interesting when we regard their emergence as social creatures and their rise to dominance and extreme diversity over a relatively short time span. Here in Arilab, I want to use modern techniques in data acquisition, visualization, and analysis.