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Thijs Janzen

@thijsjanzen.bsky.social
150 followers 284 following 29 posts

Scientific Programmer @ TRES, University of Groningen, Netherlands

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franz @franzanth.bsky.social · 06/10/2026
Hello, since Redbubble did me dirty (suspension without explanation while owing me money) let's experiment a little bit! If I've known you long enough not to abuse my work and you want a print/sticker/whatever from me, pay me what you want, I'll give you high resolution files. Try me! #Art #SciArt
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EvoBio Crash Course @evobiocc.bsky.social · 07/10/2026
There is still time to apply! You can find the registration link and course information at evobiocrashcourse.github.io We hope to make this edition our best one yet! ✨🐞🦎
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Euan Angus Young @euantheyoung.bsky.social · 07/10/2026
Delighted to share that my final PhD chapter is now published in @molbioevol.bsky.social! 🤩 Read all about our study testing whether trade-offs can explain why genetic variants promoting breast cancer persist in populations: doi.org/10.1093/molb... 🧵
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James Balamuta @coatless.bsky.social · 04/10/2026
webrarian is a new R package. It turns a folder of R scripts and data into a static website where R runs in the visitor's browser, with no compute server and nothing to install. blog.thecoatlessprofessor.com/posts/introd... #rstats #webr #webassembly
A card for the R package webrarian. Large text reads "A folder in. A website out." On the left, a small card lists a folder named lab-01 holding lab.R, setup.R and a data folder. A red arrow points from it to a browser window that shows a scatterplot of car weight against miles per gallon with brick-red points. The address coatless-wasm.github.io/webrarian is on the card.
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Fons van der Plas @fonsvanderplas.bsky.social · 01/10/2026
We have an open PhD position on how nitrogen deposition affects plant and arthropod biodiversity. The research includes large-scale fieldwork across Northwestern Europe with hands-on experiments. Interested? See www.wur.nl/en/vacancy/p...
wur.nl
PhD: Effects of atmospheric nitrogen deposition on plant and insect diversity
Are you a highly motivated and enthusiastic ecologist who wants to uncover how nitrogen deposition affects plant and arthropod biodiversity? Are you excited by the idea of combining large-scale fieldw...
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Jonathan Eisen @phylogenomics.bsky.social · 30/09/2026
Wow. Just wow. Did I say wow?
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bioRxiv Molecular Biology @biorxiv-molbio.bsky.social · 13/09/2026
DNA methylation correlates with lifespan and predicts remaining lifespan in the zebra finch www.biorxiv.org/content/10.64898/20…
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Hanna Kokko @kokkonut.bsky.social · 23/09/2026
There is still time to apply! I'll start reading the applications this Friday.
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EvoBio Crash Course @evobiocc.bsky.social · 23/09/2026
The Evobio Crash Course is coming back for its fifth edition! Join us from December 7 to December 18 for an incredible line up of classes and tutorials from amazing researchers in the field! The course is open to all, completely free and held online. Registration is OPEN, please share widely!
Poster for the Evobio Crash Course. Online from December 7-18, 2026.
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Thijs Janzen @thijsjanzen.bsky.social · 17/09/2026
How does collaborating work in Quarto? Providing comments and making corrections and such?
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Thijs Janzen @thijsjanzen.bsky.social · 24/08/2026
Update to 1.71.13: cran.r-project.org/web/packages... New additions are better support for polytomous trees, and the information table has been updated accordingly. Enjoy!
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bioRxiv Evolutionary Biology @biorxiv-evobio.bsky.social · 20/06/2026
Caste-specific ageing emerges from the evolution of resource allocation in eusocial insects www.biorxiv.org/content/10.64898/20…
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Thijs Janzen @thijsjanzen.bsky.social · 16/06/2026
Always looking to further improve, if something is missing from the package, let me know! 7/7
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Thijs Janzen @thijsjanzen.bsky.social · 16/06/2026
Lastly, in the README file, you can now find an updated table of all supported summary statistics, including information on the impact / requirement of a root branch. All statistics now also check whether the given tree is rooted if this is required for the statistic to be calculated. 6/7
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Thijs Janzen @thijsjanzen.bsky.social · 16/06/2026
The Blum statistic has been renamed to 'sshape' statistic, in line with treebalance.wordpress.com (thanks Sophie Kersting for pointing this out!). (the old 'blum' function remains available for backwards compatibility) 5/7
treebalance.wordpress.com
TREE BALANCE
Visit the post for more.
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Thijs Janzen @thijsjanzen.bsky.social · 16/06/2026
Under the hood, computation of many eigenvalue dependent statistics was sped up drastically, and made matrix-free, allowing calculation for arbitrarily large trees (previously, this was memory limited). 4/7
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Thijs Janzen @thijsjanzen.bsky.social · 16/06/2026
Two new Vignettes have been added, showing relationships between summary statistics (including the inv sum of br len), and the impact of tree size on summary statistics. 3/7
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Thijs Janzen @thijsjanzen.bsky.social · 16/06/2026
As indicated by the increase of the version number from 70 to 71, treestats added a summary statistic: the inverse sum of branch lengths. This statistic sums 1 / bl for all branch lengths between each tip and the root. It seems to be quite unrelated to other statistics. 2/7
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Thijs Janzen @thijsjanzen.bsky.social · 16/06/2026
The treestats package has been updated to version 1.71.12, in case you haven't kept track of the latest improvements, I got you covered! cran.r-project.org/web/packages... 1/7
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Chris Simms @chrisnsimms.bsky.social · 11/06/2026
This discovery amazed me: A whale "graveyard" extending over 1,200 km. The remains or fossils of about 480 whales found in a total survey area of about 0.64 square kilometres, with one of the fossils dating back more than 5 million years. 🧪 🐋 🦑 🦊 #cetaceans www.livescience.com/animals/whal...
livescience.com
Scientists discover 5 million-year-old whale graveyard stretching for hundreds of miles in the Indian Ocean
Researchers have discovered a "megasite" of dead whales along with new species of marine life feasting on the corpses.
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Stephen Turner @stephenturner.us · 02/02/2024
Phylogenetic tree statistics: a systematic overview using the new R package 'treestats' www.biorxiv.org/content/10.1... 🧬🖥️ github.com/thijsjanzen/... cran.r-project.org/web/packages...
cran.r-project.org
treestats: Phylogenetic Tree Statistics
Collection of phylogenetic tree statistics, collected throughout the literature. All functions have been written to maximize computation speed. The package includes umbrella functions to calculate all...
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Menno Schilthuizen @schilthuizen.bsky.social · 09/06/2026
Explore this gift article from The New York Times. You can read it for free without a subscription. www.nytimes.com/2026/06/08/o...
nytimes.com
Opinion | 3,000 Different Species Are Killed for Supper. Why Do We Allow It?
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Thijs Janzen @thijsjanzen.bsky.social · 09/06/2026
if their review meets a minimal bar.
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Thijs Janzen @thijsjanzen.bsky.social · 05/06/2026
Tools to go deep into R, 'deeply-R', right? right?!
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Stephen Heard @stephenbheard.bsky.social · 26/05/2026
Good teaching has a substantial amount of stand-up comedy, costuming, or whatever else can grab student attention. At first this felt cheap - but I learned to work with it.
scientistseessquirrel.wordpress.com
Good teaching is 15% straight-up entertainment – and that’s OK
I spent a good fraction of my career’s work effort on teaching, and – like most academics – I had very nearly no idea what I was doing. I’d never had a moment’s formal training in teaching, and, at…
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Riley Cran @rileycran.bsky.social · 25/03/2026
New work for GitHub: Monaspace. 🔤 A superfamily of 5 open-source typefaces for code. Full case study here: lettermatic.com/custom/monas...
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Thijs Janzen @thijsjanzen.bsky.social · 16/03/2026
@bramvandijk.bsky.social this might be right in your ballpark!
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Loukas Theodosiou @bioinformatician.bsky.social · 12/03/2026
#ggtree has a relatively steep learning curve. But after looking at a few Python alternatives eg., toytree, ETE, Bio.Phylo it's hard to match its layout versatility. 21 tree variants with just a few lines of code. #rstats #phylogenetics #bioinformatics
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Eduardo Amorim @cegamorim.bsky.social · 13/03/2026
Dogs evolved to eat your leftovers! Comparing dog & wolf genomes revealed dogs have up to 30 EXTRA copies of the amylase gene (AMY2B) that helps digest starch. This is a key genomic signature of living alongside humans & table scraps for thousands of years 🐕 www.nature.com/articles/nat... #2026MMM
Adapted from Axelsson et al. 2013 Fig 2c: Histogram showing the distribution of diploid amylase copy number in wolf (n=35, blue) and dog (n=136, red). Dogs carry more copies of the starch-digesting gene AMY2B than wolves. Additional copies make dogs better than wolves at digesting starchy foods like grains & vegetables.
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Thijs Janzen @thijsjanzen.bsky.social · 03/03/2026
Love the video explainer! Such a smart and smooth way to bring abroad your topic and avoid people having to wade through the bureaucratic representation of it. (and the pub setting is lovely as well)
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Groningen Institute for Evolutionary Life Sciences @gelifes.bsky.social · 11/12/2025
💃DaNCES with #carnivores – interested in studying predator-prey interactions? Read more about the DaNCES framework by @marinapapa.bsky.social and others, simulating #collectivebehavior of #predators and #prey below ⬇️ doi.org/10.1177/1059... #Biology #Science #Research #AdaptiveBehavior
doi.org
A Data-Inspired Framework to Simulate Collective Behaviour of Predator-Prey Systems - Marina Papadopoulou, Hanno Hildenbrandt, Charlotte K. Hemelrijk, 2025
The collective escape of prey from predators is a classic example of adaptive behavior in animal groups. Across species, individual prey have evolved a large re...
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Groningen Institute for Evolutionary Life Sciences @gelifes.bsky.social · 16/12/2025
#Coralreefs are dying off rapidly: we have reached the first #climate tipping point. 🧪 “Humans are changing the world so quickly that #corals can’t keep up anymore.” Sancia van der Meij, a marine biologist from #GELIFES, expresses her concern: rug.nl/research/gelifes/_news/2025/20251017-coral-reefs
rug.nl
Koraalriffen sterven af – en dat heeft grote gevolgen voor mens en dier
Wereldwijd sterven koraalriffen dermate snel af, dat we inmiddels het eerste klimaat-kantelpunt hebben bereikt, rapporteerden wetenschappers afgelopen...
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Groningen Institute for Evolutionary Life Sciences @gelifes.bsky.social · 21/01/2026
🔔 Update: A new #PhDPosition at the University of Groningen (@rug.nl)! If you: 🧪 have a Master's in #Biology 🌱 are interested in #PlantBiology, #Physiology, and/or #MolecularBiology Then this is a perfect opportunity! We at #GELIFES are looking forward to working with you 😉 #PhD #PhDLife
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Thijs Janzen @thijsjanzen.bsky.social · 03/02/2026
WTF
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Shaun Killen @shaunkillen.bsky.social · 25/11/2025
🧵1/9 There are 35,000+ fish species, but we have formal social-behaviour classifications for a tiny fraction. Most knowledge lives in the experience of researchers, fishers, divers, aquarists, naturalists, and Indigenous communities, but almost none of it is centralised. So we built ShoalBase.org.
shoalbase.org
ShoalBase | Join, Explore, Contribute Now
ShoalBase offers a global database on fish social behaviour, supporting research, conservation, and ecology through community contributions and visual data mapping.
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Matthew Asker @masker.science · 10/12/2025
Up to 10 doctoral positions at the Max Planck Institute for Evolutionary Biology now open for application! Start date September 2026. More info here: www.evolbio.mpg.de/imprs
Poster advertising doctoral positions in 2026 at the International Max Planck Research School for Evolutionary Biology.
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Thijs Janzen @thijsjanzen.bsky.social · 11/12/2025
Woah, that R logo is absolute fire! Immediately set it as my application icon! (and also, the workshop looks really cool as well!)
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Thijs Janzen @thijsjanzen.bsky.social · 06/12/2025
This is wonderful. High-end Technology together with straightforward ecology.
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bioRxiv Evolutionary Biology @biorxiv-evobio.bsky.social · 04/12/2025
Statistical and structural bias in birth-death models www.biorxiv.org/content/10.64898/20…
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Mike Morrison @mikemorrison.bsky.social · 12/11/2025
Play a little game and choose the right icon for each role in science. Play our CRediT Roles icon game/survey, and help make scientific authorship clearer and more accessible! creditsurvey.sciux.org #OpenScience #ScienceUX
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George Turner @dlimnothrissa.bsky.social · 26/11/2025
Part 1 version 1 of my Malawi cichlid ID guide is out now. 2 more parts for follow, with my intention being to revise, expand and improve each over time. This one is essentially a companion to our whole genome sequence paper in Science (Blumer et al. 2025). ecoevorxiv.org/repository/v...
ecoevorxiv.org
Identification of the Cichlid Fishes of Lake Malawi/Nyasa Part 1: Cyrtocarina (the ‘benthic’ or ‘hap’ sub-radiation).
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Dugdale Research Group @hannahdugdale.bsky.social · 18/11/2025
Congratulations to Dr @euantheyoung.bsky.social who defended his PhD yesterday on 'Family matters: The role of trade-offs in shaping human life-histories and health' research.rug.nl/en/publicati... @rug.nl supervised with @erikpostma.bsky.social @lummaalab.bsky.social 🎉
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Mark A. Hanson @hansonmark.bsky.social · 11/11/2025
We wrote the Strain on scientific publishing to highlight the problems of time & trust. With a fantastic group of co-authors, we present The Drain of Scientific Publishing: a 🧵 1/n Drain: arxiv.org/abs/2511.04820 Strain: direct.mit.edu/qss/article/... Oligopoly: direct.mit.edu/qss/article/...
A table showing profit margins of major publishers. A snippet of text related to this table is below.

1. The four-fold drain
1.1 Money
Currently, academic publishing is dominated by profit-oriented, multinational companies for
whom scientific knowledge is a commodity to be sold back to the academic community who
created it. The dominant four are Elsevier, Springer Nature, Wiley and Taylor & Francis,
which collectively generated over US$7.1 billion in revenue from journal publishing in 2024
alone, and over US$12 billion in profits between 2019 and 2024 (Table 1A). Their profit
margins have always been over 30% in the last five years, and for the largest publisher
(Elsevier) always over 37%.
Against many comparators, across many sectors, scientific publishing is one of the most
consistently profitable industries (Table S1). These financial arrangements make a substantial
difference to science budgets. In 2024, 46% of Elsevier revenues and 53% of Taylor &
Francis revenues were generated in North America, meaning that North American
researchers were charged over US$2.27 billion by just two for-profit publishers. The
Canadian research councils and the US National Science Foundation were allocated US$9.3
billion in that year.A figure detailing the drain on researcher time.

1. The four-fold drain

1.2 Time
The number of papers published each year is growing faster than the scientific workforce,
with the number of papers per researcher almost doubling between 1996 and 2022 (Figure
1A). This reflects the fact that publishers’ commercial desire to publish (sell) more material
has aligned well with the competitive prestige culture in which publications help secure jobs,
grants, promotions, and awards. To the extent that this growth is driven by a pressure for
profit, rather than scholarly imperatives, it distorts the way researchers spend their time.
The publishing system depends on unpaid reviewer labour, estimated to be over 130 million
unpaid hours annually in 2020 alone (9). Researchers have complained about the demands of
peer-review for decades, but the scale of the problem is now worse, with editors reporting
widespread difficulties recruiting reviewers. The growth in publications involves not only the
authors’ time, but that of academic editors and reviewers who are dealing with so many
review demands.
Even more seriously, the imperative to produce ever more articles reshapes the nature of
scientific inquiry. Evidence across multiple fields shows that more papers result in
‘ossification’, not new ideas (10). It may seem paradoxical that more papers can slow
progress until one considers how it affects researchers’ time. While rewards remain tied to
volume, prestige, and impact of publications, researchers will be nudged away from riskier,
local, interdisciplinary, and long-term work. The result is a treadmill of constant activity with
limited progress whereas core scholarly practices – such as reading, reflecting and engaging
with others’ contributions – is de-prioritized. What looks like productivity often masks
intellectual exhaustion built on a demoralizing, narrowing scientific vision.A table of profit margins across industries. The section of text related to this table is below:

1. The four-fold drain
1.1 Money
Currently, academic publishing is dominated by profit-oriented, multinational companies for
whom scientific knowledge is a commodity to be sold back to the academic community who
created it. The dominant four are Elsevier, Springer Nature, Wiley and Taylor & Francis,
which collectively generated over US$7.1 billion in revenue from journal publishing in 2024
alone, and over US$12 billion in profits between 2019 and 2024 (Table 1A). Their profit
margins have always been over 30% in the last five years, and for the largest publisher
(Elsevier) always over 37%.
Against many comparators, across many sectors, scientific publishing is one of the most
consistently profitable industries (Table S1). These financial arrangements make a substantial
difference to science budgets. In 2024, 46% of Elsevier revenues and 53% of Taylor &
Francis revenues were generated in North America, meaning that North American
researchers were charged over US$2.27 billion by just two for-profit publishers. The
Canadian research councils and the US National Science Foundation were allocated US$9.3
billion in that year.The costs of inaction are plain: wasted public funds, lost researcher time, compromised
scientific integrity and eroded public trust. Today, the system rewards commercial publishers
first, and science second. Without bold action from the funders we risk continuing to pour
resources into a system that prioritizes profit over the advancement of scientific knowledge.
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Sebastian Höhna @hoehna.bsky.social · 11/11/2025
PhD position available in evolutionary genomics/bioinformatics (hoehnalab.github.io/job_adverts/...). Topic: analyzing gene expression evolution across several firefly species and linking expression changes to genomic architecture. The position is jointly supervised with @anaevolcatalan.bsky.social
hoehnalab.github.io
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Marianthi Tangili, PhD @mtangili.bsky.social · 10/11/2025
Extremely proud of my good friend and colleague @euantheyoung.bsky.social whose work is featured in @nrc.nl. Read bellow for some excellent science and fascinating results. 👪🤰👶🧬
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Euan Angus Young @euantheyoung.bsky.social · 10/11/2025
1/13 New paper out! www.science.org/doi/10.1126/... Historical records across thousands of women showed that mothers with more children had shorter lifespans during a famine, fitting an evolutionary explanation for why we age @hannahdugdale.bsky.social @lummaalab.bsky.social @erikpostma.bsky.social
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Hadley Wickham @hadley.nz · 06/11/2025
Do you teach #rstats? Do your students complain about how lame and old-fashioned dplyr is? Don't worry: I have the solution for you: github.com/hadley/genzp.... genzplyr is dplyr, but bussin fr fr no cap.
github.com
GitHub - hadley/genzplyr: dplyr but make it bussin fr fr no cap
dplyr but make it bussin fr fr no cap. Contribute to hadley/genzplyr development by creating an account on GitHub.
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Henrik Bengtsson @henrikbengtsson.bsky.social · 05/11/2025
The detectCores() apocalypse is creeping up on us 👻🐛 As more people are getting access to 128+ CPU cores, code spinning up parallel cluster with detectCores() workers fails - not enough #RStats connections available Friends, do *not* default to detectCores(), bc www.jottr.org/2022/12/05/a...
jottr.org
Please Avoid detectCores() in your R Packages
The detectCores() function of the parallel package is probably one of the most used functions when it comes to setting the number of parallel workers to use in R. In this blog post, I’ll try to explai...
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Thijs Janzen @thijsjanzen.bsky.social · 31/10/2025
Potato-tomato
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Dugdale Research Group @hannahdugdale.bsky.social · 15/10/2025
Congratulations to Dr @friggspeelman.bsky.social who was awarded a PhD yesterday 🎉 @rug.nl on 'Socially monogamous partnerships in birds: Causes, consequences, and pair-bond strength' research.rug.nl/en/publicati... A fantastic achievement!
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