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Chadi Saad-Roy

@chadisaadroy.bsky.social
1.6K followers 1.1K following 36 posts

Assistant Professor at the University of British Columbia in the Department of Mathematics and the Department of Microbiology and Immunology Interested in disease ecology and evolution, mathematical biology chadisaadroy.wordpress.com

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Reposted by Chadi Saad-Roy
Laurent Hébert-Dufresne @lhd.bsky.social · 17/08/2026
Interested in complex systems research in beautiful Vermont? Teams @vcsi.bsky.social hope to fill postdoctoral positions on very short notice. One position is at the intersection of cognitive and epidemiological modeling. DM for details or keep an eye out for postings on here.
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Sam Díaz-Muñoz (they / ella) @sociovirology.bsky.social · 05/08/2026
Hi Everyone! I will be broadcasting live from the Social Lives of Viruses 2026 conference @zoology.ubc.ca @ubcbiodiversity.bsky.social in beautiful Vancouver BC, organized by @asherleeks.bsky.social and myself with the support of Canadian Institutes of Health Research and @moorefound.bsky.social.
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Kayla King, Ph.D. @kayla-king.bsky.social · 04/08/2026
New King lab paper @currentbiology.bsky.social led by the brilliant @luismsilva.bsky.social on parasite shedders and spreaders: www.cell.com/current-biol...
cell.com
Transmission heterogeneity emerges from uncoupled parasite shedding and spreading
Silva et al. show that disease transmission emerges from multiple ecological bottlenecks rather than a single host trait. Separating parasite shedding from downstream infection success reveals why hos...
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Luís M. Silva @luismsilva.bsky.social · 04/08/2026
New paper out in @currentbiology.bsky.social ! 🎉 Who drives disease transmission? The answer seems obvious: measure who releases or disperses the most parasites. But after dissecting transmission step by step, we found that’s often not the case. 👇 🧵 #EvoSky #IDSky www.cell.com/current-biol...
cell.com
Transmission heterogeneity emerges from uncoupled parasite shedding and spreading
Silva et al. show that disease transmission emerges from multiple ecological bottlenecks rather than a single host trait. Separating parasite shedding from downstream infection success reveals why hos...
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theobioarne.bsky.social @theobioarne.bsky.social · 21/07/2026
What can we learn from disruptions of seasonal patterns of disease during the pandemic? A new paper by @michaelsieber.bsky.social in PLOS Global Public Health, journals.plos.org/globalpublic..., was featured in the German news such as @zeit.de or @spiegel.de - and may be of interest also here. 1/3
journals.plos.org
Shifts in seasonal timing of respiratory diseases and causes of death following a natural pandemic event
Seasonal respiratory infections typically surge within a limited time window, but what determines the exact timing within a given year is not well understood. Major causes of death show a similar seas...
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Jeff Groh @jeffgroh.bsky.social · 28/07/2026
Avocados come in 2 varieties - A-types start each day female and switch to male midday. B-types do the reverse. In work just published from the last chapter of my PhD, we show this system evolved 40+million yrs ago and is regulated by alleles of 1 transcription factor www.pnas.org/doi/10.1073/...
pnas.org
Balanced polymorphism in a floral transcription factor underlies the ancient rhythm of daily sex alternation in avocado | PNAS
In avocado and certain wild relatives in Lauraceae, a highly synchronized daily rhythm of floral sex timing promotes cross-pollination between two ...
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Luís M. Silva @luismsilva.bsky.social · 05/07/2026
1/🧵 Excited to finally share my latest paper (and my first solo paper)! 🎉 Pathogens evolve. Hosts respond. But does pathogen evolution simply change the magnitude of the host response, or does it reshape which host programmes are activated? 🤔 👇 doi.org/10.1038/s420... #Anopheles #EvoSky
doi.org
Host transcriptional signatures associated with disease tolerance and environmental persistence in a mosquito–microsporidian system - Communications Biology
Mosquito host transcriptomes reflect the evolution of contrasting microsporidian parasite life histories, linking virulence and environmental persistence to distinct gene expression programmes.
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Mallory Harris, PhD @malar0ne.bsky.social · 24/06/2026
Our scoping review "Emerging frontiers in infectious disease modelling: reassessing the data-driven feedback loop between human behaviour and disease dynamics" is out now! From a group of epidemiologists, behavioural scientists, & mathematicians. royalsocietypublishing.org/rsos/article...
royalsocietypublishing.org
Emerging frontiers in infectious disease modelling: reassessing the data-driven feedback loop between human behaviour and disease dynamics
Abstract. Mathematical models have produced important insights into the relationships between disease transmission, risk perception, and human behaviour. H
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Michael Sieber @michaelsieber.bsky.social · 01/07/2026
Have ideas for your own, independent research program in Theoretical Biology? Then come and join us as a Group Leader at the @mpi-evolbio.bsky.social in Plön, Germany!
mpg.de
Group Leader in Theoretical Biology (m/f/d)
Experience in Theoretical Biology, Applied Mathematics, Theoretical Physics
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Kayla King, Ph.D. @kayla-king.bsky.social · 26/06/2026
A new primer in @microbiologysociety.org on epidemic exponential growth with @bnashby.bsky.social @chadisaadroy.bsky.social and Dan Coombs: www.microbiologyresearch.org/content/jour... Fun collaboration!
microbiologyresearch.org
Microbial Primer: Understanding the exponential growth of epidemics
Microbiology Society journals contain high-quality research papers and topical review articles. We are a not-for-profit publisher and we support and invest in the microbiology community, to the benefi...
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Pamela Martinez @pamelapm.bsky.social · 29/05/2026
I'm very excited to share this preprint led by @sorenlouislarsen.bsky.social and Chloe Yand, and made possible by the collaboration with my friend and colleague @ayesha-mahmud.bsky.social. www.medrxiv.org/content/10.6...
medrxiv.org
Same household, different choices: variation in health behaviors related to respiratory viruses in Illinois
While SARS-CoV-2 and influenza continue to place a significant burden on population health, within-household differences in decisions towards vaccination and seeking care across these two pathogens, a...
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Harman Jaggi @harmanjaggi.bsky.social · 20/05/2026
Excited to share our new preprint on noise and determinism in Trinidadian guppy population dynamics! Thanks to all collaborators: Ron, Joe, Arshed, Dave & Simon. We develop a framework for quantifying how stochasticity alters equilibrium structure, stability and vulnerability to perturbations. 1/5
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Ben Ashby @bnashby.bsky.social · 15/05/2026
Paper is now published in @journal-evo.bsky.social: doi.org/10.1093/evol...
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Evolution Letters @evolletters.bsky.social · 27/04/2026
Thermal variability alone promotes adaptation but competition can restrict evolutionary responses in viral parasites By @kayla-king.bsky.social @craigmaclean.bsky.social and others not on Bsky. doi.org/10.1093/evle...
doi.org
Competition constrains parasite adaptation to thermal heterogeneity
Abstract. Temporal thermal heterogeneity is expected to favour intermediate, generalist phenotypes that can maintain growth across a broad thermal range bu
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Asher Leeks @asherleeks.bsky.social · 28/04/2026
We're recruiting! We're looking for two graduate students to join us at UBC in Vancouver. Fully funded and open to global applicants, with flexible start-date. Topics include theory, bioinformatics, and microbiology. More details: asherleeks.com/apply #socialviruses #evosky #virosky 🧪
Leeks Lab is recruiting. We study social evolution in viruses. We're recruiting for two fully funded PhD or MSc positions, starting from September 2026. Evolutionary theory / experimental microbiology / viral bioinformatics. Experience optional / enthusiasm essential. asherleeks.com/apply
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Victor Yman @vyman.bsky.social · 15/04/2026
Excited to share our new paper out today in @natcomms.nature.com Combining multiplex serology, mathematical modelling, and experimental validation reveals arbovirus transmission dynamics despite cross-reactivity. (1/2)
nature.com
Investigating antibody cross-reactivity and transmission dynamics of alphaviruses and flaviviruses using a multiplex serological assay - Nature Communications
Arboviruses often co-circulate, but cross-reactivity hampers serological diagnostics. Here, the authors paired multiplex serology with competitive immunoassays and Bayesian modelling to quantify antib...
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Asher Leeks @asherleeks.bsky.social · 14/04/2026
The Social Lives of Viruses is coming to Vancouver, Canada, from 4th-8th August 2026! This is a free meeting dedicated to all aspects of virus-virus interactions & evolution. To apply: socialviruses.zoology.ubc.ca @sociovirology.bsky.social #socialviruses #evosky #lovevirology #virosky
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Chadi Saad-Roy @chadisaadroy.bsky.social · 13/04/2026
Honoured to have been involved in this collaboration, led by the dream team of Kylee Hoffman and @ayesha-mahmud.bsky.social
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Pedro Vale @pfvale.bsky.social · 23/03/2026
This pre-printed article discusses insect oviposition as a tractable, mechanistically grounded model for behavioural immunity, linking individual egg-laying decisions to population level disease dynamics. 🪰🦠 doi.org/10.32942/X2W...
A drawing of fruit flies eating and laying eggs in a mix of clean and pathogen-contaminated substrates.
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Daniel Cooney @danielcooney1.bsky.social · 24/03/2026
I am happy to share this new preprint with Yuxuan Zhao, Kaisheng Zhu, and Yefei Zhang on Pattern Formation in a Spatial Public Goods Dilemma due to Diffusive or Directed Motion. arxiv.org/abs/2603.21025
arxiv.org
Pattern Formation in a Spatial Public Goods Dilemma due to Diffusive or Directed Motion
The costly provision of public goods serves as a model problem for the evolution of cooperative behavior, presenting a social dilemma between the collective benefits of shared resources and the indivi...
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MMEE @mmee-int.bsky.social · 03/03/2026
For the MMEE 2026 in Cork www.ucc.ie/en/matsci/ev... note the updated deadline! Submission of talks and poster presentations: March 30th, 2026.
ucc.ie
Mathematical Models in Ecology and Evolution | University College Cork
Learn, Study and Research in UCC, Ireland's first 5 star university. Our tradition of independent thinking will prepare you for the world and the workplace in a vibrant, modern, green campus.
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Emma Zajdela @mathemmatician.bsky.social · 17/03/2026
Had fun talking with @websedgescience.bsky.social at the #APSSummit26 on how physics & math can explain fashion cycles! @aps-dsnp.bsky.social @stevenstrogatz.com
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Carl T. Bergstrom @carlbergstrom.com · 18/03/2026
The need to preserve animal culture in conservation efforts. 🪶 Gift link.
nytimes.com
How to Bring a Bird’s Song Back From the Edge of Extinction
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Kayla King, Ph.D. @kayla-king.bsky.social · 03/03/2026
A nice collaboration from post-docs in my lab 😊 onlinelibrary.wiley.com/doi/full/10.... @jingdi.bsky.social @luismsilva.bsky.social @paradyseb.bsky.social @molecularecolup.bsky.social
onlinelibrary.wiley.com
Integrating the Microbiome Into Infection Ecology and Evolution in Wild Animals
Parasites are a ubiquitous force in nature threatening wildlife populations and ecosystems. Interactions between hosts and their parasites are impacted by host-associated microbiomes, which are essen...
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Chadi Saad-Roy @chadisaadroy.bsky.social · 18/03/2026
Very excited to share our latest article in Trends in Microbiology, with @ninan-abraham.bsky.social, @chilbe.bsky.social, @ayesha-mahmud.bsky.social, and Arne Traulsen! We highlight the importance of disentangling these interactions and suggest potential paths forwards
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Carl T. Bergstrom @carlbergstrom.com · 14/02/2026
Kea! 🪶
Young kea on a corrugated metal roof
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Simon Cauchemez @scauchemez.bsky.social · 19/01/2026
Dont miss the ESPIDAM summer program in June 2026 in Stockholm, covering many key concepts for ID modelling: stochastic models, AI for ID control, nowcasting and forecasting, phylodynamics, data analysis, network models, within-host models, health economics www.statistics.su.se/english/divi...
statistics.su.se
ESPIDAM, the European Summer Program in Infectious Disease Analysis and Modelling - Stockholms universitet
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Prakhar Jaiswal @prakharj.bsky.social · 07/01/2026
Happy to share our new paper in PLOS Biology journals.plos.org/plosbiology/... Showed that population bottlenecks don't uniformly drive “cooperation” but rather selectively shape which cooperative traits evolve #evolution #ecology #microbiology @vishuguttal.bsky.social @iamsamayp.bsky.social
journals.plos.org
Bottleneck size drives the evolution of cooperative traits in an aggregative multicellular myxobacterium
Population bottlenecks shape the evolution of cooperative traits in Myxococcus xanthus through life cycle trade-offs. This study shows that stringent bottlenecks favor growth and sporulation, while re...
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Carl T. Bergstrom @carlbergstrom.com · 16/12/2025
Looking for a faculty job at one of the world's great research stations? We're looking for a marine invertebrate biologist at UW's Friday Harbor Labs. apply.interfolio.com/178804
Assistant Professor without Tenure (WOT), Marine Invertebrate Organismal Biology
University of Washington: Academic Personnel & Faculty: College of the Environment: Aquatic and Fishery Sciences
Location
Friday Harbor Labs, WA
Open Date

Dec 12, 2025
Description

The School of Aquatic and Fishery Sciences (SAFS) and Friday Harbor Labs (FHL) at the University of Washington (UW) invite applications for the Riddiford – Truman Endowed faculty Chair, a position in the Without Tenure (WOT) track at the Assistant rank with specialization in marine invertebrate organismal biology. The successful candidate is expected to develop a collaborative, extramurally-funded and nationally recognized research program based at FHL that leverages FHL’s unique marine research infrastructure and natural setting. We especially welcome candidates whose scholarship in natural systems advances fundamental knowledge and contributes to environmental stewardship. All University of Washington faculty engage in teaching, research, and service.
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Prakhar Jaiswal @prakharj.bsky.social · 06/12/2025
Recently had the chance to hear @carlbergstrom.com on information foraging in the current space of LLMs. He and @jevinwest.bsky.social have crafted a course that touches various facets of LLMs. Just finished reading through its 18 modules. Absolutely loved it! thebullshitmachines.com
thebullshitmachines.com
Modern-Day Oracles or Bullshit Machines: Introduction
A free online humanities course about how to learn and work and thrive in an AI world.
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Matthew Silk @mattjsilk.bsky.social · 26/11/2025
Its very exciting to see this paper out in @behavecol.bsky.social. These conversations, expertly led by @delphinedemoor.bsky.social, have really shaped how I now think about working with social network data. Check out Delphine's thread to learn more!
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Sophie Jean Walton @sophiejwalton.bsky.social · 11/11/2025
Super excited that the bulk of my PhD work is now preprinted! Here we used whole-community competition, or coalescence, experiments to quantify selection acting on genetically diverged strains within larger communities. (1/n) www.biorxiv.org/content/10.1...
biorxiv.org
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Ben Longdon @blongdon.bsky.social · 25/09/2025
2 job adverts on a NERC project w myself + @darrenobbard.bsky.social on “What determines the virome: ecology and the environment, evolution, or species history?” early 2026 in @uniexecec.bsky.social - Postdoc: jobs.exeter.ac.uk/hrpr_webrecr... - RA: jobs.exeter.ac.uk/hrpr_webrecr... Pls share!
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Daniel Cooney @danielcooney1.bsky.social · 23/11/2025
I'm really excited to see this paper by @fernpizza.bsky.social, @baym.lol, et al. This is a great model system for studying multilevel selection, and the experimental work builds nicely on cross-scale theoretical modeling approaches that I've enjoyed learning about over the past few years. 🧵
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Chadi Saad-Roy @chadisaadroy.bsky.social · 02/09/2025
I'm super excited to have joined @ubcmath.bsky.social and @ubcmicroimmuno.bsky.social !! Please get in touch if you might be interested in graduate studies or postdoctoral research opportunities!
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Pedro Vale @pfvale.bsky.social · 12/08/2025
This piece on infection history as a driver of individual heterogeneity in infection outcomes was fun to think about and to write with @chadisaadroy.bsky.social and Mike Boots. Also suggest that systems like #Drosophila can offer useful tools to tackle the epidemiological consequences.
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Daniel Cooney @danielcooney1.bsky.social · 18/07/2025
I am really happy to share that there will be a @nitmb.bsky.social workshop next year on mathematical and biological features of evolutionary game theory. It was really fun to co-organize this workshop with Olivia Chu, Alex McAvoy, and @jplotkin.bsky.social. www.nitmb.org/evolutionary...
nitmb.org
Evolutionary Games: Mathematical Theory and Biological Insights
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Benny Rice, PhD @bennyrice.bsky.social · 17/07/2025
Out today in Science: Our work on tropical cyclones and malaria in Madagascar. Work inspired by many and done in collaboration with many www.science.org/doi/10.1126/...
science.org
Vaccination to mitigate climate-driven disruptions to malaria control in Madagascar
Extreme weather is common in high malaria burden areas and is likely to increase in severity owing to climate change–related severe weather events. Yet, data on infection rates after these events and ...
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theobioarne.bsky.social @theobioarne.bsky.social · 09/04/2025
Corina Tarnita and I have discussed the relation between theoretical ecology and evolutionary game theory since my sabbatical in 2022. Now the paper is out, doi.org/10.1073/pnas... Cooperation in nature may not be mysterious when there are growth differences- questioning the notion of cooperation.
doi.org
Reconciling ecology and evolutionary game theory or “When not to think cooperation” | PNAS
Evolutionary game theory (EGT)—overwhelmingly employed today for the study of cooperation in various systems, from microbes to cancer and from inse...
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Kayla King, Ph.D. @kayla-king.bsky.social · 31/03/2025
Come join us at beautiful UBC! The King Lab is recruiting a Post-doc Fellow to develop mathematical theory on infectious disease evolution and emergence, together with Ben Ashby (SFU) #zoonoses #biodiversity www.zoology.ubc.ca/kinglab/join...
zoology.ubc.ca
Join Us! | King Lab
Are you interested in joining the King Lab? More information here!
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Chadi Saad-Roy @chadisaadroy.bsky.social · 17/03/2025
I’m really thrilled to announce that I will join the University of British Columbia in September as an Assistant Professor in @ubcmath.bsky.social and @ubcmicroimmuno.bsky.social! Please get in touch if you might be interested in graduate studies or postdoctoral research opportunities!
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Carl T. Bergstrom @carlbergstrom.com · 27/12/2023
Today @billhanage.bsky.social and I have a commentary in PNAS, where we discuss the role of factors other than acquired immunity in generating bell-shaped epidemic curves. Our purpose is to provide context for Saad-Roy and Traulsen's model of human behavior and disease dynamics in the same issue.
pnas.org
PNAS
Proceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans...
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