Siobhán O'Brien

Siobhán O'Brien

@siderophile.bsky.social

Assistant Prof @ Trinity College Dublin. Microbial Ecology & Evolution. Eurovision fanatic. Mammy of two party animals. Probably awake. 🇮🇪

522 followers89 following55 posts

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Siobhán O'Brien
@siderophile.bsky.social

We rely on healthy soil microbial communities to support ecosystem functioning and plant growth, but what happens when soils are exposed to multiple environmental stressors simultaneously? Spoiler: it's not good doi.org/10.1093/isme...

academic.oup.comFungicide and warming interact to reduce soil ecosystem functioningAbstract. Soil microbial communities are essential to the functioning of their ecosystems, providing vital services such as plant growth promotion and bior

Siobhán O'Brien reposted

EMPSEB 31
@empseb.bsky.social

We are thrilled to announce that the 32nd edition of the European Meeting for PhD students in Evolutionary Biology (EMPSEB) will be held in Slovenia! More details coming soon. Follow us to stay updated!

Siobhán O'Brien reposted

Meaghan Castledine
@mcastd.bsky.social

🦠Fully funded PhD project with myself, Angus Buckling, Jo Lello and Phil Mitchelmore🦠 How should we design phage therapeutics for bacterial co-infections? How do interactions between pathogens affect treatment efficacy? Please get in touch if you have any Qs 💃 shorturl.at/39Xea

Siobhán O'Brien
@siderophile.bsky.social

really enjoyed this, finally some really solid data on the question of whether cross-feeding actually matters in soil. A great mix of wet-lab experiments and genomics that feed into each other beautifully.

Christian Kost@kostchristian.bsky.social

Very happy that our paper Obligate cross-feeding of metabolites is common in soil microbial communities just came out in Nature Microbiology. See here 👇 Paywalled version: www.nature.com/articles/s41... Free read-only version: rdcu.be/fBHAb

nature.comObligate cross-feeding of metabolites is common in soil microbial communities - Nature MicrobiologyCultivation-dependent techniques, computational analyses and genome-scale metabolic models show widespread amino acid auxotrophies, suggesting that soil microorganisms exist within integrated ecologic...

Siobhán O'Brien reposted

Sadhbh Dodd
@sadhbhnidhubhda.bsky.social

So lovely to have finished the last conference of my PhD in the same place that I started 4 years ago🥹 talk about a full circle moment !

Siobhán O'Brien@siderophile.bsky.social

And that’s a wrap on #MENI2026! What a great day of microbial evolution research, and a pleasure to host at Trinity with @paulinedscanlan.bsky.social

Siobhán O'Brien reposted

Ákos T Kovács
@evolvedbiofilm.bsky.social

Fungicide Drives De Novo Evolution of Multidrug Resistance in the Plant Growth Promoting Rhizobacterium, Pseudomonas fluorescens Evolutionary Applications by @kelbrick.bsky.social, @jpjhall.bsky.social and @siderophile.bsky.social onlinelibrary.wiley.com/doi/10.1111/...

onlinelibrary.wiley.comFungicide Drives <fi>De Novo</fi> Evolution of Multidrug Resistance in the Plant Growth Promoting Rhizobacterium, <fi>Pseudomonas fluorescens</fi>Soil microbial communities underpin key ecosystem processes, including plant health, nutrient cycling and primary productivity. In agricultural soils, beneficial soil bacteria are often exposed to mu...

Siobhán O'Brien reposted

James Orr
@jamesaorr.bsky.social

One of ecology’s oldest questions - how does population growth change as density increases? - remains surprisingly contentious. In our new @plosbiology.org paper we contribute to the ongoing debate by applying the idea of “Growth-Density Inversion”: doi.org/10.1371/jour.... 1/6

doi.orgGrowth-density inversion in Escherichia coli reveals superlinear, not sublinear, density dependenceSublinear density dependence has been widely reported empirically, but this is at odds with resource competition theory. This study uses a tightly controlled test in a microbial model system to reveal...
Siobhán O'Brien
@siderophile.bsky.social

We rely on healthy soil microbial communities to support ecosystem functioning and plant growth, but what happens when soils are exposed to multiple environmental stressors simultaneously? Spoiler: it's not good doi.org/10.1093/isme...

academic.oup.comFungicide and warming interact to reduce soil ecosystem functioningAbstract. Soil microbial communities are essential to the functioning of their ecosystems, providing vital services such as plant growth promotion and bior
Siobhán O'Brien
@siderophile.bsky.social

In our new paper, led by @kelbrick.bsky.social, we show that fungicide and warming applied together causes massive non-additive losses in community respiration and metabolic capacity, with legacy effects that also reduced plant growth. The stressors applied alone had little/no impact on functioning

Siobhán O'Brien
@siderophile.bsky.social

Hence, assessing the impact of fungicide on soil microbes as a single stressor may underestimate fungicide effects under future (& current) climate conditions, where multiple stressors may interact.

Siobhán O'Brien reposted

Gavan Reilly
@gavreilly.com

“The famine is over! The curse be damned!! Hit the nuclear button! Mayo have won the All-Ireland!!” An all-time great sports commentary moment from Stephen Grealis and Martin McHugh on Mayo’s Midwest Radio. #gaa

Siobhán O'Brien reposted

European Society for Evolutionary Biology
@eseb.bsky.social

Safe to say that we are very excited about this here at ESEB! Huge thanks to Brian Golding for entrusting us with the fantastic service that you have created and curated for the years! Follow @evoldir.bsky.social

EvolDir@evoldir.bsky.social

📣 EvolDir is now managed by @eseb.bsky.social! We are delighted to be taking the reins and express our gratitude to both Brian Golding who began this service to the community in the mid-1980s and to @rdmpage.bsky.social who ran this account until now 👏 You can now find evoldir here: evoldir.net

Siobhán O'Brien
@siderophile.bsky.social

New data from the lab, showing how fungicides can drive rapid selection for multidrug resistance In soil bacteria - even under warming. This was probably the most clear cut data I’ve ever seen (collected by @kelbrick.bsky.social), with clear selection on efflux pump regulator PFLU_3160. Enjoy!

bioRxiv Microbiology@biorxiv-microbiol.bsky.social

Fungicide drives de novo evolution of multidrug resistance in the plant growth promoting rhizobacterium, Pseudomonas fluorescens https://www.biorxiv.org/content/10.64898/2026.04.01.715857v1

Siobhán O'Brien
@siderophile.bsky.social

Just a few weeks left to register - places are filling up fast!

Siobhán O'Brien@siderophile.bsky.social

MENI is back! Join us in Dublin this August 2026 for our 3rd Meeting for Microbial Evolution in Ireland. We are delighted to have @rachelmwheatley.bsky.social @drrebeccajhall.bsky.social @jpjhall.bsky.social and @tweethinking.bsky.social join us as keynote speakers this year. miniurl.com/MENI

Siobhán O'Brien reposted

Daniel Padfield
@padpadpadpad.bsky.social

PLEASE SHARE. PhD Opportunity with me, Ben Raymond and Jan Engelstaedter and Andrew Letten at University of Queensland. Experimentally testing mechanisms of how temperature may change selection and spread of AMR in E. coli. Coupled with some advanced modelling and sequencing. 🧪🦠 #microsky

Siobhán O'Brien
@siderophile.bsky.social

Some very juicy emails in these files also - especially like this absolute belter from Bob Trivers

Stu West@stuwest.bsky.social

Strange discovery that an email about inclusive fitness was forwarded to Jeffrey Epstein, with the emailer quoting Jerusalem and comparing themself to Einstein. Are you one of the >100 evolutionary biologists now in the Epstein files? www.justice.gov/epstein/file...

Siobhán O'Brien reposted

Stu West
@stuwest.bsky.social

Strange discovery that an email about inclusive fitness was forwarded to Jeffrey Epstein, with the emailer quoting Jerusalem and comparing themself to Einstein. Are you one of the >100 evolutionary biologists now in the Epstein files? www.justice.gov/epstein/file...

Siobhán O'Brien
@siderophile.bsky.social

Combined anthropogenic stressors (warming and fungicide) synergistically reduce soil microbial ecosystem functioning (respiration, metabolic capacity, plant performance, fungicide resistance). A tour-de-force by @kelbrick.bsky.social! www.biorxiv.org/content/10.6...

biorxiv.orgFungicide and warming interact to reduce soil ecosystem functioningSoil microbial communities are essential to the functioning of their ecosystems, providing vital services such as plant growth promotion and bioremediation. However, intensively managed environments such as agricultural soils are increasingly challenged with multiple harsh environmental stressors from the compounding effects of climate change and conventional agricultural practices. Understanding how soil communities will respond to environmental stress along multiple axes is key for predicting how environmental change will impact terrestrial soil ecosystems. We combine experimental evolution with community phenotyping, 16s rRNA metabarcoding, fungicide resistance assays and plant experiments, to show that fungicide and warming temperatures together drive a synergistic reduction in soil community respiration rates, metabolic capacity and plant growth promotion (Hordeum vulgare), which would have been missed by looking at stressor effects independently. Dual stressors caused widespread loss of metabolic activity, particularly for carbohydrates and carboxylic acids, highlighting impairment of community function. Fungicide-evolved soil isolates had a 16-fold increase in fungicide resistance, but only in the absence of warming, suggesting that the dual stressor treatment constrained fungicide adaptation. Together, our findings suggest that the number of stressors (rather than the nuances of individual stressors) may be key for predicting soil microbial community responses to environmental change across multiple axes. ### Competing Interest Statement The authors have declared no competing interest. BBSRC, BB/T009446/1 IRC New Foundations and Community Foundation Ireland, NF/2022/39250777 NERC, NE/S00713X/1

Siobhán O'Brien reposted

EMPSEB31
@empseb31.bsky.social

🏔️ EMPSEB31 is heading to the mountains! This year we’ll meet in Oberwiesenthal, Germany (8–12 June 2026), a quiet mountain town in the Ore Mountains, right on the Czech border. Think forest trails, open skies, and fresh air. Join us for a week of science and fun!🌿 #EMPSEB31 #EvoBio #PhD