FY2014 Annual Report

Biodiversity and Biocomplexity Unit

Assistant Professor Evan P. Economo



Our lab seeks to understand how ecological and evolutionary processes interact to generate and regulate biodiversity across spatiotemporal scales and levels of biological organization.  Living systems are diverse from gene sequences to organismal morphology to communities and ecosystems.  Our goal as biologists is not just to document and catalogue this diversity, but understand the complex interactions and dynamics that generate and sustain biological variation.  The majority of research in FY2014 concentrated in three areas; our project on the evolution of the hyperdiverse genus Pheidole, and our “Global Ant Biodiversity Informatics (GABI)” project which focuses on compiling analyzing global distributions of past and present ant biodiversity, and work on a high-throughput ecological genomics pipeline to study high-throughput phylogenetics and population genomics.  Other ongoing projects include biodiversity theory, 3D morphometrics, and complex systems research.

1. Staff

  • Dr. Evan P. Economo, Assistant Professor
  • Dr. Benoit Guénard, Researcher
  • Dr. Béatrice Lecroq, Researcher
  • Dr. Masashi Yoshimura, Staff Scientist
  • Dr. Georg Fischer, Postdoctoral Scholar
  • John Deyrup, Technician
  • Nitish Narula, Technician
  • Masako Ogasawara, Research Assistant
  • Cong Liu, PhD Student
  • Patricia Wepfer, PhD Student
  • Yafei Mao, PhD Student
  • Hitomi Shinzato, Research Administrator

2. Collaborations

  • Evolution of hyperdiversity in the ant genus Pheidole
    • Type of research: joint research
    • Researchers:
      • Prof. L. Lacey Knowles (University of Michigan, USA)
  • New quantitative approaches for Island Biogeography
    • Type of research: joint research
    • Researchers:
      • Prof. Kostas Triantis (University of Athens, Greece)
  • Evolutionary Radiation of Terataner and Tetramorium ants
    • Type of research: joint research
    • Researchers:
      • Dr. Francisco Hita Garcia (Damstadt, Germany)
  • Global hyperdiversification of trap-jaw ants (Strumigenys)
    • Type of research: joint research
    • Researchers:
      • Doug Booher (UCLA)

3. Activities and Findings

3.1 Evolution of hyperdiversity in ecological, phenotypic, and geographic networks: testing the taxon cycle and alternatives in Indo-Pacific Pheidole

This project is a collaboration between OIST and U. of Michigan, funded by the National Science Foundation (USA).  The first phase of the project, now completed, was to generate a well-resolved phylogeny of the genus with representative taxa from around the globe, and more comprehensive sampling from our main area of interest; Indo-Malaya and Melanesia.  Our molecular dataset now includes over 1300 individuals from over 500 species from around the globe. 

In a parallel effort, we have created several datasets that complement the phylogenetic dataset and will be used for comparative analysis.  In our lab at OIST, we imaged over 1000 specimens with standard views.  We developed a system of geometric morphometric landmarks and a suite of discrete and continuous character data, and recorded data for all species in our study.  In addition, we have compiled a comprehensive database of distributional data for species in the genus.  In FY2014 we used these datasets to test integrated hypotheses for the joint evolutionary dynamics of morphology, ecological habit, and biogeographic distribution in the genus, and this work has been recently published (Economo et al., Proc. B., 2015)At the same time, we have been working on follow-up analyses on the evolutionary biogeography of this genus.

Figure 1:  a) Global Phylogeny of the ant genus Pheidole based on 9 loci (Economo et al. 2015).  Pheidole originated in the neotropics and subsequently radiated in the New World.  A single colonization of the Old World followed by a colonization of Australia-New Guinea led to two subsequent radiations.  b) Biogeographic modules detected by network analysis of Pheidole distributions (Economo et al. in preparation).

3.2 Global Ant Biodiversity Informatics (GABI) Project

Our understanding of large-scale biodiversity patterns is strongly biased towards a few groups of vertebrates and plants, while studies on insects, by far the most diverse organisms, are scarce. To address this gap in our knowledge, the Global Ant Biodiversity Informatics project (GABI) aim to compile over 200 years of ant research into a single database providing distribution information for all ant species. This will allow assessing our current knowledge, and to predict present and future distribution of all species; and when combined, analyze ant diversity across large scales. Questions relative to the ecological and evolutionary patterns of ants will be addressed at the light of the distribution of other organism groups, gradients of environmental factors or of specific biological traits (e.g. size).  In FY2014 we began analyzing this dataset, which now consists of over 1.3 million ant occurrence records.  We are currently using these data for analyses of global patterns of diversity, endemism, and diversification rate.

3.3 Biodiversity and Evolutionary Ecology of Indo-Pacific Ant Communities

Ants are among the most ubiquitous and ecologically dominant animal groups. Over millions of years, ant biodiversity has evolved and dispersed from Asia and Australia through the vast network of Pacific islands.  More recently, humans have unintentionally introduced many species from around the globe into the Pacific. We seek to understand the historical and contemporary processes that regulate ant biodiversity over time.  

In FY2014 we continued our projects on Indo-Pacific ants.  We processed recent collections made from Borneo and China. We have published new taxonomic (e.g. Sarnat et al., 2014, Hita Garcia et al. 2015) and molecular works (Clouse et al. 2014) on the systematics and evolution of species in this region. 

In addition, we began a large effort to understand the genetic structure of the entire ant fauna in Fiji, using our high-throughput ecological genomics pipeline (next section).  The goal is to sequence and develop population genomic data across the entire community and test hypotheses such as the taxon cycle and others.

3.4  OKEON Okinawa Environmental Observation Network

In collaboration with the Mikheyev unit here at OIST, in FY2013 we initiated a major initiative called OKEON, the Okinawa Environmental Observation Network.  The goal is to develop an observation system to measure and monitor the environment of Okinawa, in collaboration with the people of Okinawa.  The primary scientific goal is to develop long-term space-time data series from sites across the island, the goal of the to setup a high-throughput population genomics pipeline. 

In FY2014 we initiated operation of OKEON, focusing on the high-throughput sequencing pipeline and GIS initiatives.  The pipeline will combine sample processing and curation, molecular methods and lab automation, next-generation sequencing, and bioinformatics (e.g. Tin et al. 2014).  The data will be used to rapidly generate phylogenies and population genomics data from field samples.  The goal of the GIS efforts are to consolidate data layers on the current and historical status of Okinawa’s land environment and make it freely available.  Concaminant to that, we are modeling land use change over the last 40 years and its downstream effects.  The next fiscal year will build upon these efforts by initiating field sampling and outreach components of OKEON.

3.5 3D X-ray Computed Tomography for Insect Phenomics


Figure 2:  X-Ray computed tomograms showing the internal and exterior surface structure of a Pheidole major.

Since the earliest biological studies, description and quantification of biological structures has been a basic goal of biology as well as a first step toward deeper understanding of ecological and evolutionary processes.  In Entomology, the primary imaging tools have traditionally been optical microscopy and SEM, which are essential for certain tasks and allow us to see complex structures well. But these are limited in our ability to quantitatively characterize complex shapes, surfaces, and textures.  X-Ray CT has the potential to complement existing tools by providing a digital 3D image of the interior and exterior of the organism.  These images can be manipulated, dissected, measured, and quantified.  We have been developing imaging and post-processing techniques to better quantify the functional morphology of ants, including both external and internal structures.  In FY2013, we led the procurement and installation of an Zeiss X-Ray Microscope as a common resource at OIST and have initiated a project to develop a database of 3D ant tomograms.  We have since been developing post-processing routines to filter, segment, and quantify the images.  In FY2014 we have focused on refining scanning techniques and building a database of scanned specimens to support various projects.

3.6  Biodiversity Theory 

We continue our work developing theoretical approaches to understanding biodiversity dynamics.  In FY2014 we continued work on network models of spatial biodiversity processes, and applications to diversity dynamics in general across social and biological systems. We are also working on new statistical methods for inferring processes in island biogeography.

4. Publications

4.1 Journals

  1. Liu, C., Guénard, B., Hita Garcia, F., Yamane, S., Blanchard, B., Yang, D., Economo, E. New records of ant species from Yunnan, China. Zookeys, doi: 10.3897/zookeys.477.8775 (2015)
  2. Hita Garcia, F., Sarnat, E., Economo, E. Revision of the ant genus Proceratium Roger (Hymenoptera, Proceratiinae) in Fiji. ZooKeys, doi: 10.3897/zookeys.475.8761 (2015)
  3. Economo, E., Klimov, P., Sarnat, E., Guénard, B., Lecroq, B., Knowles, L. Global phylogenetic structure of the hyperdiverse ant genus Pheidole reveals the repeated evolution of macroecological patterns. Proceedings of the Royal Society Series B, doi: 10.1098/rspb.2014.1416 (2015)
  4. Tin, M., Economo, E., Mikheyev, A. Sequencing Degraded DNA from Non-Destructively Sampled Museum Specimens for RAD-Tagging and Low-Coverage Shotgun Phylogenetics. PLoS One, doi: 10.1371/journal.pone.0096793 (2014)
  5. Sarnat, E., Rabeling C., Economo, E., Wilson, E. First record of a species from the New World Pheidole flavens-complex (Hymenoptera: Formicidae) introduced to the southwestern Pacific. BioInvasions Records, doi: http://dx.doi.org/10.3391/bir.2014.3.4.13 (2014)
  6. Jarvis, E., et al. Whole-genome analyses resolve early branches in the tree of life of modern birds. Science, doi: Doi 10.1126/Science.1253451(2014)
  7. Ikeda, T., Yoshimura, M., Onoyama, K., Oku, Y., Nonaka, N., Katakura, K. Where to deliver baits for deworming urban red foxes for Echinococcus multilocularis control: new protocol for micro-habitat modeling of fox denning requirements. Parasites & Vectors, doi: 10.1186/1756-3305-7-357 (2014)
  8. Guénard, B., Cardinal-De Casas, A., Dunn, R. High diversity in an urban habitat: are some animal assemblages resilient to long-term anthropogenic change?. Urban Ecosystems, doi: 10.1007/s11252-014-0406-8 (2014)
  9. Clouse, R. M., Janda, M., Blanchard, B., Sharma, P., Hoffmann, B. D., Andersen, A. N., Czekanski-Moir, J. E., Krushelnycky, P., Rabeling, C., Wilson, E. O., Economo, E. P., Sarnat, Eli M., General, D. M., Alpert, G. D., Wheeler, W. C. Molecular phylogeny of Indo-Pacific carpenter ants (Hymenoptera : Formicidae, Camponotus) reveals waves of dispersal and colonization from diverse source areas. Cladistics, doi: 10.1111/cla.12099 (2014)

4.2 Books and other one-time publications

Nothing to report

4.3 Oral and Poster Presentations

  1. Economo, E., Guénard, B., Weiser, M., Narula, N. Global patterns of diversity and diversification in ants. The 62nd Ecological Society of Japan annual meeting, Kagoshima, Japan (2015).
  2. Yoshimura, M. Male genitalia and ant evolution. International Union for the Study of Social Insects 2014, Cairns, Australia (2014).
  3. Yoshimura, M. The diversity in reproductive system fond in Mystrium (Hymenoptera: Formicidae). 74th conference of The Entomological Society of Japan, Higashi-Hiroshima, Hiroshima (2014).
  4. Yoshimura, M. An evolutionary study of the male genitalia of ants. 57th meeting of The Myrmecological Society of Japan, Niigata, Japan (2014).
  5. Liu, C., Guénard, B., Economo, E. How do agricultural practices in South China affect ant communities?. International Union for the Study of Social Insects 2014, Cairns, Australia (2014).
  6. Guénard, B., Weiser, M., Economo, E. Ant global diversity: opening new possibilities in ant-biology. International Union for the Study of Social Insects 2014, Cairns, Australia (2014)
  7. Economo, E., Sarnat, E., Guénard, B., Lecroq, B., Knowles, L. Island communities in the context of global hyperdiversification. International Union for the Study of Social Insects 2014, Cairns, Australia (2014)
  8. Economo, E. The evolutionary ecology of island ant communities in the context of global hyperdiversification. Evolutionary Community Ecology @ Kyoto University, Kyoto, Japan (2014)
  9. Economo, E. Ecological and Evolutionary Assembly of Pacific Island Ant Communities. 61st Annual Meeting of Ecological Society of Japan, International Conference Center Hiroshima (2014)

5. Intellectual Property Rights and Other Specific Achievements

Nothing to report

6. Meetings and Events

6.1 The biodiversity and biogeography of woody plants: Informatics age answers to questions from the age of exploration

  • Date: 6/26/2014
  • Venue: OIST campus
  • Speaker: Andrew Kerkhoff, Associate Professor, Kenyon College

6.2 Wingless workers underlie the evolutionary success of ants

  • Date: 1/29/2015
  • Venue: OIST campus
  • Speaker: Christian Peeters, Professor, CNRS

7. Other

Nothing to report.