2024 HALDANE PRIZE SHORTLIST: Jahangir Vajedsamiei discusses his paper “Predicting key ectotherm population mortality in response to dynamic marine heatwaves: A Bayesian-enhanced thermal tolerance landscape approach“, which has been shortlisted for Functional Ecology’s 2024 Haldane Prize for Early Career Researchers:
👋 About the author
I am honored to be nominated for the Haldane Prize for my recent work published in Functional Ecology. My journey as a marine ecologist has been rooted in the fascinating yet vulnerable realm of coastal ecosystems. I began with a Master of Science in Marine Biology at Shahid Beheshti University in Tehran, Iran, under guidance of Dr. Behrouz Abtahi. Subsequently, I spent 4.5 years at the Iranian National Institute for Oceanography, collaborating with researchers such as Dr. Abolfazl Saleh to investigate how spatiotemporal changes in environmental conditions affect coral communities in the world’s warmest sea, the Persian Gulf.
Building on these experiences, I pursued my doctoral studies at the GEOMAR Helmholtz Centre for Ocean Research Kiel and Christian-Albrechts-Universität zu Kiel, Germany. Under the supervision of Prof. Dr. Martin Wahl, Dr. Christian Pansch, and Prof. Dr. Frank Melzner, my PhD research explored the underappreciated role of environmental fluctuations as modulators of stress in marine organisms.
🌊 Recent Research: A Bayesian-Enhanced Thermal Tolerance Landscape
My postdoctoral research at GEOMAR, in collaboration with Prof. Dr. Frank Melzner (Benthic Ecology group leader), Mr. Niklas Warlo (then an MSc student), and Prof. Dr. H.E. Markus Meier (Leibniz Institute for Baltic Sea Research), focused on the grave threat posed by climate change-induced marine heatwaves. Shallow coastal ecosystems are particularly susceptible to extreme temperature fluctuations, which can cause severe stress and mortality among resident species.
To study these impacts, we used the blue mussel (Mytilus), a foundational species along temperate coastlines. Our approach involved two experimental setups: (1) a controlled laboratory experiment subjecting mussels to constant heatwave conditions, and (2) an outdoor mesocosm experiment simulating dynamic temperature fluctuations. We monitored survival rates of both juvenile and adult mussels, as well as post-heatwave recruitment, to assess the resilience of new generations.
🦪 Predictive Modeling with ABC-SMC
A key innovation of this research was the integration of Approximate Bayesian Computation with Sequential Monte Carlo (ABC-SMC) to refine Thermal Tolerance Landscape (TTL) models using real-world dynamic heatwave data. Our results showed that ABC-SMC–refined TTL models accurately predicted survival declines under both constant and fluctuating heatwave scenarios. Notably, dynamic heatwaves exerted stronger adverse effects on the recruitment of new generations compared with mortality in older mussels—yet our models also suggest that mussel populations may retain significant resilience against even the most extreme projected heatwaves in the coming century.
🐚 Current Focus: Mitigating Environmental Stressors
I am currently a researcher at the Leibniz Institute for Baltic Sea Research, Warnemünde (IOW), where I continue to investigate how environmental stressors shape marine ecosystems. My ongoing projects include quantifying carbon capture and release in coastal habitats, particularly within mussel beds. Through this work, I strive to deepen our collective understanding of marine ecosystem dynamics and to develop predictive tools that support the conservation and sustainable management of vital coastal resources under changing climatic conditions. It is a privilege to have my work recognized for the Haldane Prize, and I remain committed to advancing research that illuminates and safeguards marine ecosystems for future generations.
Read the full list of articles shortlisted for the 2024 Haldane Prize here.
