The Evolution of Robustness

In Darwin’s theory of evolution by natural selection, the key phrase is “survival of the fittest”: those organisms that are best fit to carry out the tasks of living in their world are the ones that survive. But they won’t live forever — they must have offspring that inherit the traits that made them fit in order for evolution to proceed.

This conceptual framework is fine for understanding the evolution of traits that affect survival and numbers of offspring. But what about the rules of inheritance themselves? These rules are also organismal traits, although they need not have any effect on how well the parents survive or how many offspring they have. In fact, the rules of inheritance say what the offspring are, rather than how many there are. Classical mathematical models of evolution have little to say about the evolution of these rules. How, then, can “survival of the fittest” shape the rules of inheritance?

Read the full story on the EES blog

The Tooth of Time

One of the main reasons evolution can be difficult to grasp, or even accept, is the time scales involved. Biological evolution does usually not occur right in front of our eyes (other than in laboratory experiments), but happens over many generations. Most people, especially in increasingly urbanized environments largely disconnected from the natural world, will never get to see any significant evolutionary change during their own lifetime.

Read the full piece in ORBITER magazine

Kurt Gödel: A postcard from Vienna

Kurt Gödel was one of the greatest mathematicians of the 20th century. He made many important contributions to mathematical logic and philosophy, but is best known for his incompleteness theorems. Loosely speaking, the theorem states that the dream of phrasing all of mathematics in terms of a formal system, based on a set of axioms and the rules of logic, is bound to fail: there will always be statements that are true but whose truth cannot be proved within the axiomatic system itself. This abruptly ended a longstanding quest by some mathematicians to construct a set of axioms sufficient for all of mathematics.

Read the full story in Plus magazine

How Did Life Begin?

My 3-part series of popular science articles on the history of origin of life research has been published in ORBITER magazine. Part 1 presents a “pre-history” of how the origin of life became a real scientific problem in the first place (for many centuries it actually wasn’t!). Part 2 presents a brief overview of 20th century scientific progress on origin of life research, from the idea of a primordial soup to that of an RNA world, and beyond. Finally, part 3 presents a brief history of autocatalytic sets, from Stuart Kauffman’s original idea published in 1971, to some of the most recent insights.


I’m staying in a little village called Lackenberg, to do some hiking in the area. After arriving, I walked around a bit in and around the village, and then watched a beautiful sunset from the balcony of my hotel room.

Read more

A Partial Lunar Eclipse

On Tuesday 16 July, 2019, there was a partial lunar eclipse visible from most of Europe. I decided to spend the night in a hut halfway up a mountain near Vienna to watch this eclipse, and invited some colleagues to come along. We were lucky that it was a mostly clear sky that evening, making for excellent viewing from just over 1200m up.

Read more

Beating the Avatar Blues

When the movie Avatar was released in late 2009, a strange thing happened with many people who saw it. They got depressed, even suicidal. It wasn’t because they disliked the movie, but because they liked it so much, they wanted to live in a gorgeous, almost utopian, world like Pandora, rather than on planet Earth. Pandora, the fictitious alien moon portrayed in the movie, has an amazing natural beauty, and human-like inhabitants (the Na’vi) living in peaceful harmony with it.

Read the full piece on ORBITER magazine

The Power of Snooker

A particular mathematical relationship known as a power law has been observed in many day-to-day situations, from the frequencies in which words are used in natural languages to the connectivity distribution in Facebook friendship networks. As it turns out, though, such a power law can also be found in snooker statistics. And if the amazing Ronnie O’Sullivan continues to produce centuries at the same rate, the mathematical correspondence will be even better!

Read the full story on Plus magazine

The February 2019 Supermoon

A “supermoon” happens when a full moon occurs around the same time that the moon is at its closest point to the earth (perigee) in its elliptical orbit around our planet. This means that the full moon will appear extra large and bright. In fact, it can appear up to 30% larger and brighter compared to the opposite, a “micro-moon”, when the full moon occurs around the same time that it is furthest away from the earth (apogee). Last night happened to be the brightest supermoon of 2019.

Read more

The Chat Noir Cabaret

My good friend Charles Tichenor has been playing the piano since he was a little kid. And he’s still going at it tirelessly at his weekly Chat Noir Cabaret show at the Los Magueyes Mexican restaurant on Burro Alley in Santa Fe, NM, USA. Here’s a short slide show to give an impression of his performances.

Read more

A Home for Complex Systems Science

In complex systems science, the notion of complexity is often summarized with the phrase “the whole is more than the sum of its parts“. This expression can be traced all the way back to the early Greek philosopher Aristotle (Metaphysics, Book VIII, 1045a.8-10) and mathematician Euclid (Elements, Book I, Common Notion 8). It was therefore appropriate to have a conference on complex systems in Greece. As part of a delegation from the Institute for Advanced Study of the University of Amsterdam, I attended this conference to learn more about recent advances in complex systems science, and about some ancient Greek history. Read more