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Leiden University celebrates curiosity at 449th Dies Natalis

How has evolution shaped our curiosity? And how does that curiosity ensure that we now have the technological ability to discover whether we are alone in the universe? This was all covered during the celebration of Leiden University’s 449th Dies Natalis.

It is our role to be curious, Hester Bijl said in her opening address. ‘By constantly asking new questions, we keep knowledge alive for the time when we need it.’ But we also have to take responsibility as academics, she stressed. Because new insights and technologies have implications for the whole of society. That makes it important to ‘have an honest conversation about the results, the uncertainties and sometimes also the risks of our work’, she said.

Hester Bijl
Mariska Kret gives her Dies speech

Origins of our behaviour

Why is it that we curb our curiosity and have reservations about people who are different from us?  Professor Mariska Kret (Cognitive Psychology) reflected on this in her Dies lecture. She looks at the origins of our behaviour from an evolutionary perspective. Bonobos, who once lived in a food-rich, safe area, appear curious about and share food with bonobos that they do not know. Chimpanzees, however, who mainly lived in less hospitable conditions, are wary of other groups.

Kret’s research shows that humans and other primates use emotional expressions to judge whether a stranger can be trusted. Subtle expressions such as pupil dilation play an important part in this because they subconsciously show how someone is really feeling. ‘Uncovering the evolutionary underpinnings of our behaviour would help to further solve the puzzle of human drivers and, where possible, help people make better decisions’, said Kret. 'Curiosity is the basis of science. Fundamental, curiosity-driven research often has more applications in society than research that solves a direct problem.’

Quiz on research objects

Between the various speeches, science communications adviser Marieke Epping sparked the audience’s curiosity. In an online quiz, she asked questions about special objects from various Leiden studies and researchers provided the answers.

Lennard Kwarkernaak, for example, showed the audience a block of material that proved to be rubber that can count This material has a ‘memory’, which couuld track how many lorries drive over a bridge, for instance. Archaeologist Valerio Gentile brought a replica bronze sword, which fencers have actually fought with. The damage to the sword tells us something about the fighting styles used in the Bronze Age.

LUMC researcher Anne van der Does showed the audience a plastic plate, which proved to be an organ-on-a-chip. The chip contains all the cells that are found in our lungs but in miniature. The technique can be used to test new drugs for example, and for further research into lung disease. Cognitive psychologist Michiel van Elk had the audience guessing about what proved to be a ‘god helmet’. This can be used to induce spiritual experiences. At least, that is what visitors to the Lowlands Festival thought, but in reality it is a placebo helmet that does nothing at all. Yet many participants in his study proved susceptible to spiritual trips, and that is what  Van Elk was researching.

Sara Seager

Honorary doctorate for astrophysicist Sara Seager

Canadian-American astrophysicist Sara Seager, a professor at the Massachusetts Institute of Technology, received an honorary doctorate for her research on the atmospheres of exoplanets: planets orbiting stars other than our sun. A pioneer in her field, Seager has developed groundbreaking methods to help discover another Earth. ‘From the birth of a single star billions of years ago to our gathering today, we’ve all been part of an ongoing cosmic story’, she said in her acceptance speech. ‘Let us all commit to continue exploring the unknown.’

Space for bold ideas

After a musical interlude by the Leiden Student Choir and Collegium Musicum Orchestra, Seager gave the second Dies Lecture. She spoke about her search for life outside our solar system but also about the importance of bold ideas in science. In her research on exoplanets, the line between what is considered normal and folly is constantly shifting, she said. She was repeatedly told in the 1990s that the field had no future.

‘But astronomers have since found thousands of exoplanets’, Seager continued, showing data from the James Webb Space Telescope. ‘Let this land: by eye we can see signs of an exoplanet atmosphere. An incredible time for astronomy.’ Seager also spoke about sophisticated space telescopes that are specially designed to find and identify Earth twins. ‘We still have a long journey ahead of us, but are thrilled with where we are now.’ She then wished everyone, ‘clear skies, clear thoughts, and your own incredible journey of exploration.’

Annetje Ottow spoke to three people who are doing something for society with their curiosity.

President of the Executive Board Annetje Ottow discussed curiosity with three people with links to the university who use their curiosity to help society. Alumnus Ruben van Dijk wants to inspire young people and get them excited about their archaeological heritage. With his Past Forward programme, he demonstrates this archaeological heritage and relates it to their world. For example, he cooks Ancient Roman recipes with them.

Alumnus Willemijn Vader is trying to understand why some cancers respond to certain therapies whereas others do not. With her Vitroscan company, she is using patient cells to see whether it is possible to predict a treatment’s success.

Marret Noordewier, an assistant professor and head of research at the Psychology & Economic Behaviour Knowledge Centre, works on policy issues with lots of different partners. She wants them to understand the reality of people with financial stress. And she looks at whether these people can cope with the system they end up in.

At the end of the ceremony, Ottow looked ahead to the Dies Natalis in 2025. Then it will be time for a big celebration: the university will celebrate its 450th anniversary. In a video. Ottow revealed the theme of the anniversary: ‘ahead of the times’. 

Re-watch the live stream of the Dies Natalis.

450 years of Leiden University

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Photos: Monique Shaw

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