Thilo Gross

→ Are you interested in multiscale phenomena such as the complex dynamics that arise in biology, chemistry, neuroscience, and physics when multiple spatial or temporal scales interact? 🧪

Then join us this summer in Groningen for the summer school:

lnkd.in/gViS3cCZ

The call for our 2026 Postdoc Cohort is now open. We offer 4 full-time positions. Apply until August 24th. hifmb.de/jobs
Please spread the word.
#postdoc #jobsinscience #marinebiodiversity #antarctica
@awi.de @hillebr1.bsky.social @ibaums.bsky.social @thilogross.bsky.social @merenbey.bsky.social 🦑

They have to destroy scientific research to eliminate the point at which civilians from every warzone connect and recognize themselves. How can you build a quantum computing lab without Iranians? Or an ML theory lab without Israelis? Better to let progress die than to allow that they might meet.

The rot is spreading ...

This focus on using research funding to support business is harmful.

How individual systems and their connections react to each other to ensure stability of the whole. We live in a complex world with a plethora of connections and interactions. Many important processes, such as power grid dynamics, ecological interactions, opinion formation, or brain plasticity, can ...

Our new article in Chaos. One of my favorite articles so far. Connecting different disciplines and building on recent breakthroughs in ancient fields (Linear Algebra!).

link.growkudos.com/1ebwrn9qkn4

doi.org/10.1063/5.02...

insane moment in world history right here

The dynamics of microbial cooperation... Cheap metabolites make for shaky friendships; but pricier ones can keep the peace... 🦠

Thanks @janamassing.bsky.social for leading the charge! And great working again w/ @akfbio.bsky.social & @thilogross.bsky.social

I would just leave the country in which there is a financial crisis in higher education. In fact, I have.

Norrköping campus at sunset

We are hiring postdocs in Computational Social Science
📍SweCSS, Norrköping, Sweden
⏰Deadline June 3
🔗https://liu.se/en/work-at-liu/vacancies/26854
Please apply // help us spread the word

New paper led by @janamassing.bsky.social, with @jdyeakel.bsky.social and @thilogross.bsky.social, on dynamics of cooperative bacteria: www.biorxiv.org/content/10.1...

To explore this further we need models that can exhibit both tipping and gradual transitions in biodiversity. The cross-feeding model proposed here is a very simple model that fills this need.

Of course there is still much room for improvement, but this is how far we got.

Thresholds for ecological responses to global change do not emerge from empirical data - Nature Ecology & Evolution The utility of the threshold paradigm, such that relatively small perturbations drive abrupt ecosystem changes, is challenged by a synthesis of 36 meta-analyses, which detected few signatures of thres...

There is another reason why this is interesting. Presently there is a debate whether or when biodiversity in diverse systems can actually tip. See for example this paper by @hillebr1.bsky.social et al.

www.nature.com/articles/s41...

In the lab we then supply the community with growth media which supply some of the metabolites. This effectively removes these metabolites as limiting requirements. So this can be also modelled as an attack: C(x)->C(B(x)), where B describes the medium.
...

Illustration of the microbial sampling procedure. As a result of sampling a tipping point is crossed.

Why is this interesting: First, it shows why diversity tends to collapse in small samples. By missing some of the producers of metabolites we can cross the tipping point. In the equations we can model this effect of sampling as an attack on the network: We replace M(x)->M(A(x)).

Of course this is the classic two-folds scenario of tipping, so when we vary a second parameter (e.g. mean number of producers per metabolite), we find a nice Cusp bifurcation. This shows that the transition from high diversity to low diversity can occur by tipping/gradually depending on params...

Figure showing that changing the mean number of consumer requirements leads to tipping. The transitions occur in the characteristic pattern of two fold bifurcations with a region of hysteresis in the middle.

For reasonable choices of parameters this system exhibits tipping points between a low and high diversity state ...

Equation: c* = C(m*), m*=1-M(1-c*)

So this becomes a percolation problem. The whole setup is captured by two nice eqs. Here c* is num of bacteria chance m^* is num of metabolites, and C, M, are the GFs for number of requirements, number of producers per metabolite ...

So this becomes a directed bipartitie network, but if you want you can also think of it as a multilayer net or hypergraph.

What fascinates me is the algebraic structure: Bacteria in the system need ALL their requirements to be met, whereas metabolites need ONE of their producers to be present...

So this is about about crossfeeding, that is the exchange of molecules between bacteria. Think of this as a network where each node is a species of bacteria or a type of metabolite. Directed links indicate which metabolites are required by, or produced by the bacteria. ...

Cross-feeding creates tipping points in microbiome diversity | PNAS A key unresolved question in microbial ecology is how the extraordinary diversity of microbiomes emerges from the interactions among their many fun...

Hey, new paper by @cleggtom.bsky.social and me is just out in @pnas.org. This combines a lot of things that start with B: Biodiversity, Bipartite Networks, Bifurcations, Bacteria, ...

www.pnas.org/doi/10.1073/...

And yes, I know, Fig 1 looks like one of 'those' papers but please read on ...

A picture of our group member Laura Barth. She is wearing a maroon winter jacket, navy blue knitted beanie, and glasses. You can see her dark curly hair sticking out under the beanie. Laura is standing outdoors on a wooden pier by a calm body of water. She has a slight, friendly smile and is looking at the camera. Behind her are forested hills and a cloudy sky, creating a serene atmosphere.

Meet our group members! Time to hear about the wonderful @laurabarthm.bsky.social:

"Hi, I’m Laura! I’m a physicist by training and a PostDoc researcher working with physics-informed neural networks to enhance the interpretability of ecological models and improve forecasting.

YouTube video by Complexity Papers Bridge-building, Chinese Postman, and Hierholzer's Algorithm (NC 3-2)

I finally got around to edit the second part of the video on the walk (it mostly explains the math of how it was made).
youtu.be/g52Lcr3rRHc
(The first part is here: youtu.be/Mnaf2Y_ydq8 )

Everybody should read this ...

Great idea!

A picture of our group member Srilena Kundu. The picture shows a woman with shoulder-length black hair, wearing glasses, a black top, and a patterned vest. She smiles brightly at the camera. She is outdoors on a sunny day, standing on a grassy area with trees and a large body of water visible in the background. The sky is clear with scattered white clouds.

Meet our group members! Today let's hear from the wonderful @srilenak.bsky.social:

"Hi, I’m Srilena, a HIPP postdoc in the Biodiversity Theory group. I have a background in Applied Mathematics with a research focus on theoretical ecology. My research approach combines mathematical modeling, ...

Thank you for finding this great content!

new on @NaturePhysics review:
"Network renormalization"
www.nature.com/artiles/s422...
Preprint: arxiv.org/pdf/2412.12988

#complexnetworks #brain #connectome

The link seems to be broken.

Indoors I use the same shure MV as everybody, but I do most of my videos outside, which also solves this.