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.

Contact Info and Websites:

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.

Contact Info and Websites:


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.


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.

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 study 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.

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.


Nao Takashina, JSPS 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.

Evropi Toulkeridou, PhD 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 to 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 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.

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.


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.

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.

Lazzat Aibekova, PhD Rotation Student (Winter 2019)

I am a first year student and I am currently doing my second rotation in the Biodiversity and Biocomplexity unit. In this lab I am analyzing the diversification patterns of five Madagascar ant genera, to find whether the evolutionary radiation is random or staged.


Fumika Azuma, Research Technician


Upon completing my undergraduate studies in University College London, I interned at Arilab to map the global distribution of all known ant species in order to identify species richness on a global scale. As a technician, I will continue with this project, while assisting lab members through micro-CT scanning and specimen curation. My interests lie in understanding the roles of historical and contemporary factors in controlling the spatial pattern of diversity, especially in tropical ecosystems. For my undergraduate thesis, I utilised GIS and spatial packages in R to map and model mangrove regrowth trajectories in abandoned aquaculture ponds in Singapore.

Susan Kennedy, Postdoctoral Researcher

I’m interested in applying high-throughput methods to understand the biodiversity, network structure, and functional traits of arthropod communities. I’m currently working on a project characterizing arthropod biodiversity across multiple Pacific archipelagoes, using metabarcoding of mixed samples to obtain high data yields at low cost. We’re also using molecular gut content analysis to characterize trophic relationships among these arthropods. By comparing arthropod communities in several island systems and across temporal, spatial and disturbance gradients, we can understand how the structure and function of these communities change over time and in response to environmental perturbation. For my PhD (UC Berkeley, Prof. Rosemary Gillespie), I used similar methods to assess how trophic ecology changes over evolutionary time within the adaptive radiation of Hawaiian Tetragnatha (long-jawed orbweaver) spiders. While I find all arthropods fascinating, spiders are my first love, and one of my personal goals has always been to share my enthusiasm for these marvelous little animals – to convert arachnophobes into arachnophiles wherever I go. Spiders and insects are among the most phylogenetically, ecologically and behaviorally diverse organisms in the world, and they have a tremendous amount to tell us about life on Earth.


Alexandre Ferreira, Visiting Research Student


I am a PhD student at Universidade Federal do Paraná, Brazil, under supervision of Rodrigo Feitosa and Marcio Pie, focusing my research on the taxonomy of the genus Pheidole in the Atlantic Forest. Besides the taxonomy of the group, I am also interested in the geometric morphometrics tools to explore morphological evolution, integration and spatial variation. In Economo Unit, I have been working with microCT data to understand the integration between the mandible and head shape in Pheidole and trying to correlate these variations with food preference.

Yazmín H. Zurita-Gutiérrez, PhD Student

I am interested in understanding how networks of interactions work. What are the rules behind them, what features stabilize them, and what makes them resilient or vulnerable. Ideally studying cascading effects.

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