I am an ecologist and ethnobiologist with broad interest in the impacts of modern and traditional human activities on forest ecosystems. I am also fascinated by the interplay between biodiversity loss and cultural erosion. I study the ecological ramifications of culture change and work to preserve and revitalize traditional ecological knowledge (TEK). I enjoy not only the academic dimensions of research but also translating research findings into practical applications to address modern challenges related to biodiversity and climate change.
1. Amazon Forest
The implication of subsistence activities for plant dispersal and forest biodiversity
My prior research has shaped my motivation to understand the nexus between biological and cultural diversity. I lived with the Hotï to investigate the ecological and cultural implications when indigenous communities shift from semi-nomadic to sedentary lifestyles. I was able document their TEK on weevil cultivation, which revealed a wealth of information palm and weevil ecology, some of which remains unstudied. I also quantified how shifts in the intensity of subsistence activities could influence dung-beetle biodiversity. To gain deeper insights into plant dynamics under minimal human disturbance, I investigated plant-animal interactions at Cocha Cashu, Peru to discern how plant dispersal, genetics and competitive interactions might be altered with human disturbance.
My current work in the Amazon focuses on understanding how hunting and resource extraction influence forest regeneration and tropical biodiversity. Working with collaborators at OIST and the San Diego Zoo Alliance, I integrate field experiments, genetic studies, spatial analyses, to understand how human activities alter plant-animal interactions, and plant regeneration through their impacts on plant dispersal, gene flow, and competitive interactions. To effectively monitor how mammal movements influence plant dispersal and spatial genetics across multiple sites and scales, we are developing NGS sequencing workflow and bioinformatic pipeline to identify snps for several non-model Amazonian plant species.
Forest tree functional and taxonomic biodiversity across disturbance gradient and recovery and resilience to typhoon events
I lead plant biodiversity research at OIST with the support of collaborators including our amazing OIST OKEON field team. Okinawa is a biodiversity hotspot of Japan housing many endemic and endangered species. Okinawan forests makeup only 0.1% of forests in Japan, yet they are home to nearly a third of the 1250 plant species documented in the country.
We established and censused 14 tree plots across the island between 2019-2021. Our data on tree diversity, stand biomass serves to address questions on how forest tree functional and taxonomic diversity and stand biomass changes across a human disturbance gradient. With increasing typhoon frequency and intensity, we are using canopy cover data to assess typhoon damage and to understand how tree diversity, stand density influence forest resilience and typhoon recovery. Our tree data provides baseline information for ongoing projects with arthropods, birds, and mammals. We have also collected plant samples to eventually generate a DNA barcode reference library for future research.
Soil DNA metabarcoding
Soil microbial diversity are important components of the bottom-up effects in forest ecosystems. Microbial diversity is shaped by ongoing feedbacks between above and below ground processes, and these are further affected by human disturbance and climate. We have initiated preliminary work to refine the field and laboratory protocols to eventually assess differences in soil microbial diversity across our tree plots to understand the role of plant biodiversity, human disturbance, and typhoon events on microbial.
Reforestation and traditional knowledge
Forests have long served as sanctuaries to humans, with people managing their resources for their survival. Since the advent of the industrial era however, the balance of human-forest interaction has been disrupted, leading to widespread deforestation, and exacerbating our present climate challenges. University campuses globally span vast areas and some like OIST, built within biodiverse habitats. As institutions of research the research and education, we are poised to promote biodiversity and cultural conservation by example and through education and outreach. Using our tree biodiversity data and research on traditional knowledge, we initiated a volunteer-led campus reforestation project to replant native trees within in the lawn areas of the campus adjoining small forests. The hope is to continue such reforestations on campus and in the nearby communities to both promote biodiversity conservation and revitalize interest in the traditional uses of trees as forest corridors and natural barriers against typhoons.
OIST: Evan Economo
San Deigo Zoo Wildlife Alliance: Varun Swamy, Mrinalini Erkenswick Watsa
Field Project International: Gideon Erkenswick
Kennedy, S, Calaor J, Zurápiti Y, Hans J, Yoshimura M, Choo J, Andersen JC, Callaghan J, Roderick GK, Krehenwinkel H, Haldre Rogers, Gillespie RG, Economo EP (2022) Richness and resilience in the Pacific: DNA metabarcoding enables parallelized evaluation of biogeographic patterns. Molecular Ecology https://doi.org/10.1111/mec.16575
Choo J, Gill B, Zuur A, Zent EL, Economo EP (2019) Impacts of an indigenous settlement on the taxonomic and functional structure of dung beetle communities in the Venezuelan Amazon. Biodiversity and Conservation 29:207-22 http://doi.org/10.1007/s10531-019-01879-5
Choo J, Carrasco C, Alvarez-Loayza P, Simpson BB, Economo EP (2017) Life history traits influence the strength of distance- and density-dependence at different life stages of two Amazonian palms. Annals of Botany 120:147-158 https://doi.org/10.1093/aob/mcx051
Sheehan MJ, Choo J, Tibbetts EA (2017) Heritable variation in colour patterns mediating individual recognition. Royal Society Open Science https://doi.org/10.1098/rsos.161008
Choo J, Juenger TE, Simpson BB (2012) Consequences of frugivore-mediated seed dispersal for the spatial and genetic structures of a neotropical palm. Molecular Ecology 21:1019-1031 https://doi.org/10.1111/j.1365-294x.2011.05425.x
Choo J, Ishak H, Simpson B, Mueller U, Juenger T (2010) Characterization of 14 microsatellite loci in a tropical palm, Attalea phalerata (Arecaceae). American Journal of Botany 97:105-106 https://doi.org/10.3732/ajb.1000281
Choo J, Zent EL, Simpson BB (2009) The importance of traditional ecological knowledge for palm-weevil cultivation in the Venezuelan Amazon. Journal of Ethnobiology 29:113-128 https://doi.org/10.2993/0278-0771-29.1.113
Choo, J (2008) Potential ecological implications of human entomophagy by subsistence groups of the Neotropics. Terrestrial Arthropod Reviews 1: 81-93 https://doi.org/10.1163/187498308x345442
Choo J, Pang E, and Prociv P (2000) Hookworms in dogs of Kuching, Sarawak (North Borneo). Transactions of the Royal Society for Medicine and Health 94: 21-22 https://doi.org/10.1016/s0035-9203(00)90425-5