Tokyo Metropolitan University Graduate School of Science
Department of Biological Sciences
Tokyo Metropolitan University Graduate School of Science
Department of Biological Sciences

Research Laboratories

ANIMAL ECOLOGY (Adam L. Cronin and Yu Okamura)

Research Overview

Our laboratory is interested in looking at the behavior of biological systems from individuals in groups to the ecosystem level. We want to understand how these behaviors evolve and dictate ecological roles, as well as how organisms utilize them to adapt to change. To this end, we use different groups of organisms, with particular focus in hymnopterans such ants, bees, and wasps.


Some of our work include the following themes: 

  1. Complex systems biology
  2. Evolutionary ecology
  3. Invasive species ecology
  4. Pollinator network ecology
  5. Host plant adaptation mechanisms in herbivorous insects
  6. Ecological and evolutionary understanding of interactions between organisms


We are always looking for enthusiastic graduate students. Don't hesitate to contact us if you are interested in doing research with us! 


Department Laboratory Page

Animal Ecology Laboratory


Current Projects

(1) Complex systems biology

Highly integrated animal societies such as colonies of social insects can achieve complex tasks far beyond the capabilities of any single individual. These often-sophisticated collective tasks are achieved without centralised leadership and with only rudimentary individual intelligence. We study how groups can compile information to exploit the intelligence of the swarm, and how swarm-based systems may be more robust and flexible than individuals in the execution of group tasks such as decision making and collective movement.

(2) Evolutionary ecology

Social organisms can exploit a range of life-history strategies unavailable to individual organisms through the extended phenotype of the group, and this may help explain their success in adapting to different environments. Social insects, for example, have a range of adaptive mechanisms to cope with different environments, including alternative reproductive strategies, shifts in trophic ecology and/or variation in social structure. We explore the evolutionary ecology of these adaptive mechanisms using a combination of field-based ecological and behavioural studies, computer simulations, natural isotopic analysis, and molecular phylogenetic and population genetic analyses.


(3) Invasive species ecology 

Social organisms employ a variety of reproductive strategies that can influence offspring survival and dispersal. These strategies, differing in the degree of offspring investment, may significantly impact species ecology and ecosystem dynamics as a whole. By combining field studies, genetic analyses, and mathematical modeling, we examine how various reproductive and dispersal strategies in ants shape life-history traits. 


(4) Pollinator network ecology 

Invasive species are a growing global concern but also provide an opportunity to study the adaptive dynamics of adaptive responses to novel environments. We use various invasive species as models to investigate how ecological factors and invasion history influence behaviour, ecology, and evolution, both of the invasive species and the invaded community.


(5) Host plant adaptation mechanisms in herbivorous insects 

Plants and herbivorous insects exhibit remarkable diversity and play crucial ecological roles in terrestrial ecosystems. In plant-herbivore interactions, plants employ a wide array of chemical compounds as defense mechanisms, while herbivores have evolved adaptations to overcome these challenges posed by their host plants. This interaction has been shaped by co-evolution, driving speciation bursts and escalating trait evolution on both sides. Our research focuses on the molecular mechanisms, ecological consequences, and evolutionary aspects of host plant adaptation in herbivorous insects. By investigating these processes, we aim to understand how the co-diversification of plants and herbivores has been driven. To address this question, we employ a wide range of approaches, including molecular experiments, genome editing, field studies, and population genetics.


(6) Ecological and evolutionary understanding of interactions between organisms  

Organisms live in a complex web of interactions with various other organisms. These interactions take many forms, such as predator-prey relationships between plants and herbivorous insects, as well as symbiotic or parasitic associations. We focus on understanding the mechanisms that establish these interactions in the field and their ecological consequence especially focusing on non-model insect species. We conduct research on a wide range of topics, including the evolution of sex pheromones among closely related insect species and symbiotic relationships between insects and microorganisms. Our approach primarily utilizes chemical ecology methods to uncover the underlying principles of these interactions.


Staff Highlight

Dr. Adam L. Cronin
Associate Professor
Dr. Yu Okamura
(岡村 悠)
Associate Professor
 (from April 2025)
Email:
adamcronin[at]gmail.com 
okamura-bs[at]tmu.ac.jp
Read more:

(Researchgate Profile)

(ResearchMap Profile)

(TMU Faculty Profile (Japanese))

(ResearchMap Profile)

(TMU Faculty Profile (Japanese))



Lab Information:
Department Laboratory Page (Japanese)


Recent Publications

1. Coinvasional disruptions to island pollinator networks 

Marta Quitián, Isaac Planas-Sitjà, Maki Morooka, Anna Traveset, Simon M. Tierney, Adam L. Cronin. Conservation Biology, e70304. Apr 2026

2. Variation in soldier investment is linked to the evolution of termite soldier defense strategies 

Akiya Satoh, Isaac Planas-Sitjà, Adam L. Cronin & Nobuaki Mizumoto. Evolutionary Ecology, 40, 21. Feb 2026

3. Unravelling the biosynthesis of phenylphenalenones: insights from metabolites and enzymes in Musella lasiocarpa 

Hui Lyu, Lukas Ernst, Yoko Nakamura, Yu Okamura, Tobias G. Köllner, Katrin Luck, Benye Liu, Yu Chen, Ludger Beerhues, Jonathan Gershenzon, Christian Paetz. Phytochemistry Letters, 69:103109. Oct 2025

4. It’s complicated: the role of false brood cells as an anti-parasite strategy in Hymenoptera is not simple despite their ubiquity 

Lucas R Hearn, Adam L Cronin, Danielle Giuretis, Mark I Stevens, Michael P Schwarz. Biological Journal of the Linnean Society, 145(4): blaf048. August 2025

5. Inter-sexual phenotypic divergence is correlated with habitat structure in an invasive lizard 

Maki Morooka, Marta Quitián, Adam L Cronin. Behavioral Ecology, 36(3): araf033. Apr 2025

6. Varroa mites exhibit strong host fidelity despite spatial desegregation of mite and host species in Vietnam

Thi Thu Ha Nguyen, Yong-Chao Su & Adam L. Cronin. Apidologie 56, 36. Mar 2025

7. Symbiosis and horizontal gene transfer promote herbivory in the megadiverse leaf beetles 

Roy Kirsch, Yu Okamura, Marleny García-Lozano, Benjamin Weiss, Jean Keller, Heiko Vogel, Kayoko Fukumori , Takema Fukatsu, Alexander S. Konstantinov, Matteo Montagna, Alexey G. Moseyko, Edward G. Riley, Adam Slipinski, Fredric V. Vencl, Donald M. Windsor, Hassan Salem, Martin Kaltenpoth, Yannick Pauchet. Current Biology. 35(3) 640-654.e7. Feb 2025

8. Phenylphenalenones and Linear Diarylheptanoid Derivatives Are Biosynthesized via Parallel Routes in Musella lasiocarpa, the Chinese Dwarf Banana 

Hui Lyu, Lukas Ernst, Yoko Nakamura, Yu Okamura, Tobias G. Köllner, Katrin Luck, Benye Liu, Yu Chen, Ludger Beerhues, 

Jonathan Gershenzon. Organic Letters, 26(26) 5522-5527. Jun 2024  

9. De novo genome assembly and annotation of Leptosia nina provide new insights in the evolutionary dynamics of genes involved in host-plant adaptation of Pierinae butterflies 

Yu Okamura, Heiko Vogel. Genome Biology and Evolution, 16 (5) evae105. May 2024

10. Functional heterogeneity facilitates effectual collective task performance in a worker-polymorphic ant 

Takuto Sakai, Isaac Planas-Sitjà, Adam L Cronin. Behavioral Ecology, 35(1) arad096. Jan 2024



See more: (Google Scholar (Cronin)) (Researchgate (Okamura))


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