Our little apartment in Medellín is on the 7th floor. But that doesn’t prevent nature from doing its thing.

The food chain starts with a banana. We cut it up and put it on a wooden feeder. So far, we have been visited by Guacharacas (see video), Mieleros, Bichofues, Candelarias, Azulejos, Verdulejos, Mayos and today even a Carpintero.

No matter how hard these birds try to scrape the last piece of banana from the feeder, there is always something left. But it doesn’t go to waste! Because, believe it or not, ants find their way up to the seventh floor. And they feast on what is left of the banana.

(A small discussion can be found underneath this Lemmy post).

For some years now, I have seen this graph go around on social media. I think it’s a powerful image, because it shows us so clearly that it is happening in our lifetime and under our watch.

For that reason, I have also used it in some of my classes, yet always with the disclaimer the the graph does not show when it was made.

Nodules are red, violates are blue

I was today years old when I learned why the nitrogen fixing nodules on the roots of legumes tend to be red when you open them. It has to do with the Great Oxidation Event, which happened around 2.5 billion years ago, and is directly connected to the reason why our blood is red.

(This article also exists in Spanish: link)

Nitrogen is naturally scarce. It might make up the bulk of what we call “air”, but this nitrogen exists as N₂, and most organisms have no clue what to do with that. “Most organisms”, because there are a few bacteria that have evolved the capacity to capture nitrogen from the atmosphere, and turn it into molecules that are biologically useful, like NH₃.

If you like to go down a Python rabbit hole with me, to explore some of the basic dynamics of the greenhouse effect, Please continue. If not, get out while you still can!

Ok, so this page of Kump et al.’s “The Earth System” (third edition, 2010) briefly presents a simple model of the greenhouse effect: the “greenhouse effect of a one-layer atmosphere”.

It basically shows (with interesting, but ultimately, unnecessarily complex equations) that if…

The shamelessness with which gringos in Medellín relish in their financial advantage puzzles me.

“I worked hard for the money I’m spending.”

I’m sure you did, but not even close to as hard as you make your Colombian counterpart work for it.

“But I’m helping people by spending my money here.”

If you are serious, stop trying to 1. find the cheapest way to 2. satisfy your preferences and desires, and find ways to make your undeserved comfort alleviate other people’s undeserved discomfort.

Meeting yourself

Warning: This post contains some spoilers about the movie “Coherence”.

Imagine that, right now, through the door that is closest to you, someone walks in, and it is… you. A complete, full, physical double of yourself. This other you is as perplexed as you: similarly shocked to find a complete, full, physical double of itself.

If you think this would merely be interesting and cool you probably have not seen the movie “Coherence”.

Intro and disclaimer

I read this book with some friends. Someone had recommended it, and we felt that it was an appropriate time to reflect on what antisemitism has meant in the past, to better understand what it means in the present.

At the start I was a bit sceptical about this contemporary relevance: after all, a lot has happened since Sartre wrote this book (written in 1944, published in 1946). For example, to just mention something, the founding of the state Israel (in 1948). But after reading the book, I was surprised how helpful some of the arguments still are (at least to me).

Today I was accused of “tokenization” in sharing this powerful essay by Masha Gessen on Mastodon (see the reactions under this post).¹ Because of the character limit of a Mastodon post (at least on my server), I decided to turn my response into a little blog post.

In short, the principle that I was accused of violating looks like this: as an outsider to a community, I should not share/boost the view of a minority of that community, when that view disqualifies the concerns that are held by the majority of that community.

The current international order is like:

Put your own oxygen mask on first, order a glass of wine, purchase something shiny from the duty free shop, watch your favourite movie, take a little nap, before assisting others.

Mastodon post

In the spring of 2022, more than a hundred lecturers, organized under the banner of Casual UvA, laid down their marking work and joined a strike. Their demands were simple: 1) permanent contracts for structural work, 2) opportunities for professional development and 3) workload transparency.

After several weeks, the University of Amsterdam presented a new teachers policy that was meant to address the core concerns and frustrations of its lecturers. In response, the lecturers agreed to suspend the strike, hoping that the new policy would be as effective and generous as the university’s central management claimed it would be.