This thesis focuses on protoplanetary disks: flattened structures of gas and dust around young stars in which planets are expected to form and grow.

Promotores: S.F. Portegies Zwart, E. M. Rossi

The work presented in this thesis is based on ALMA surveys of protoplanetary disks in three star-forming regions: Lupus, OMC-2, and NGC 2024.

This thesis explores the theoretical and observational properties of distant massive galaxies that harbour active black holes in their centres and shine brightly at radio wavelengths.

In the research programme Microbial Sciences we perform state-of-the-art research in the field of biotechnology and microbial sciences.

In this thesis, I targeted the orchid genus Lepanthes, one of the six genera of angiosperms that surpasses 1,000 species in the Neotropics, as a study model to investigate the evolutionary processes that promoted species diversifications.

The mission of the Plant Science research programme is to contribute to the sustainable production of high quality crops, flowers and high-value bio-based products. This is realised by generating fundamental knowledge of basic biological processes related to development of plants and their interaction…

Has there been continuity or change in US counterterrorism policy since 9/11? What factors led to the continuity or change, and how do we classify any such continuity or change?

In the past years access to EU law has been significantly enhanced via services such as EUR-Lex. This development not only allows for easy retrieval of individual legal acts, but for collecting information about the evolution of EU law in the aggregate as well.

Recent studies of Neandertal body mass and skin surface indicate raised energetic requirements in this lineage compared to anatomically modern humans.

This interdisciplinary research project explores several adaptive machine learning methods which can give insight into the interaction between human and machine. The ultimate goal is open and natural communication between humans and AI that should result in mutual trust, cooperation and coordination…

β-Lactamases are enzymes that can break down β-lactam substrates, such as antibiotics, preventing the use of these antibiotics for the treatment of various infectious diseases. However, some compounds, β-lactamase inhibitors, can block these enzymes allowing for possible treatments using a combination…

All crested and marbled newts (the genus Triturus) suffer from an unusual genetic abnormality, called a balanced lethal system, that kills exactly half of their offspring. How can a trait so disadvantageous have survived millions of years of natural selection?

In an unpredictable environment bacteria evolve the same strategy as shareholders who try to protect themselves against unpredictable swings in the stock market. Experimental evolution biologist Dr Bertus Beaumont published an article on this discovery on 5 November in the journal Nature.

The Institute of Biology Leiden (IBL) is an internationally oriented institute for research and education in biology. Some of their staff members are part of the Leiden Human Evolution Collective.

For the first time, researchers were able to grow organoids from snake venom glands. The lab-grown 3-D structures can produce snake venom molecules. This is a major step in finding treatments to tackle snakebite, which causes over 100,000 deaths each year. Publication in top journal Cell.

Leiden biologists have shown that a gene present in plants, animals and yeasts does play an important role in plants, although for years the gene was considered unimportant. It turns out the gene plays a crucial role in the development of vascular tissue in plants. Publication in Nature Plants on 11…

Bacteria found in soil specialise in the colony by division of labour. Some of the bacteria produce antibiotics, even when it comes at the expense of their individual reproduction success, to defend their colony against competitors. Publication in Science Advances.

The origin and evolution of galaxies are closely tied to the cyclic feedback processes between stars and the interstellar medium (ISM).

The research that is united in the Liveable Planet programme, touches upon a wide range of aspects of human life. The goal is to deepen and expand the scope and to connect more researchers. The following case studies are examples of current research projects.

Promotores: Prof.dr. J. Zaanen & Prof.dr. K.E. Schalm

Insect egg development in a warming world: the eco-evo-devo of embryonic developmental time: What is the genetic basis of developmental time?

Our research regularly receives attention in the (Dutch) popular media. Here is an overview.

An understanding of our past helps students grasp the complexities of our world today and how our current biology and social structures came to be. By leveraging student interest into what makes us human, we help guide them to engage with topics ranging from archaeology to climate change, medicine,…

CERQ is a questionnaire measuring cognitive coping strategies developed by Dr. Nadia Garnefski and Dr. Vivian Kraaij.

Twenty years from now, the world population is estimated to be around 9 billion people (now 8 billion). In combination with the improvements in living standards and the corresponding growth in consumption, this population will result in an enormous increase in the demand for food, consumables, water…

If an algorithm has to learn to understand language, simply having a lot of data doesn’t help much. Like us, a computer has to learn the language in interaction with others. Tessa Verhoef is fascinated by how this interaction works.

These are the proposed research projects for LEAPS 2019. Please note that not all projects will go ahead and some may still be added in the near future. Final funding decisions lie with the Faculty sponsors. And please make a note that if you are interested in an ESA project, to check if your state…

An international team of researchers including Leiden archaeologists has produced convincing evidence that 300,000 years ago pre-Neanderthal people had a high level of cognitive complexity. New insights into early human capabilities and behaviour.

The IBL has four Divisions: Animal Sciences, Plant Sciences, Microbial Sciences and Science Communication and Society.

The formation of stars and planets happens over multiple scales, which can interact. In particular, planet formation happens in the dense, complex environment of star forming regions.

The Graduate School Office of the Faculty of Archaeology provides support to the Faculty Board in PhD affairs. It is also closely linked with the Leiden University Strategy and Academic Affairs Department and other University Leiden Graduate Schools.

Reputation literature has provided crucial insights about the evolution of the US regulatory state. Daniel Carpenter’s influential account painstakingly demonstrates the relevance of reputation to bureaucratic ‘power’ and to early institutional state-building in the US context. We argue that adopting…

This Thesis shows discoveries in non-linear astrochemical kinetics as well as a deeper analysis of dark clouds chemistry.

Historical evolution law

The impact of the phenotypic plasticity of P. aeruginosa and the distinct CF lung microenvironments on antibiotic drug effects and resistance remains poorly understood.

This dissertation investigates the propagation of solitary waves in the presence of random disturbances.

Exchanges between different cultures and institutions of learning have taken place for centuries, but it was only in the twentieth century that such efforts evolved into formal programs that received focused attention from nation-states, empires and international organizations.

Update : March 2020 A.J. Mills

This project investigates the well-preserved agricultural terraces of the Inn valley and the evolution of resource use in the inner Alps.

The information below concerns courses that our group teaches in Leiden. 

Research at Leiden Observatory spans the full width of modern astrophysical enquiry. It is based on observation, theory, simulation, and experiment. Two broad clusters characterize the ongoing research. Within each theme, researchers carry out their personal and specialized research programme. The two…

To answer questions that look beyond individual entities, network science studies the interactions taking place in complex systems. These complex systems can often have temporal information on when an interaction occurs.

The Institute of Biology Leiden (IBL) is an internationally oriented institute for research and education in biology. We are part of the Faculty of Science at Leiden University.