The vast majority of species on earth are ectotherms or cold blooded animals, comprising 99.9% of all animal life. The rate at which ectotherms live their lives varies dramatically, with some animals completing their lifecycle in mere days, while others take decades. What is the physiological basis for this slow-fast lifestyle continuum?
Temperature may hold the key. Temperature directly affects physiological rates such as growth and development. As a consequence, warm-reared animals exhibit a fast lifestyle, whereas cold-reared animals exhibit a slow lifestyle. These thermal responses are poorly understood, but increasing evidence suggests limiting oxygen availability at higher temperatures to be an important explanatory factor.

In this PhD project you will take a cellular perspective to test the idea of oxygen shortage in warmer waters. You will study how (zebra) fish growth and development change with temperature and oxygen, using fish that have different cellular attributes (cell size and membrane fluidity). The project will include ecophysiological studies (quantifying oxygen requirements, growth and development in an experimental set-up), morphometric studies (gill morphology) and cellular studies (cell size and membrane properties).
By studying the physiological basis of responses to temperature in ectotherms, we not only get a better understanding of how animals respond to climate change, but also gain insight into the very fabric of life: the causes giving rise to the variation in life histories.

You are a creative, enthusiastic, result-driven person and have:
- an MSc in biology (e.g. ecophysiology, comparative physiology or thermal biology);
- experience with experimental design and scientific writing;
- good oral and written communication skills, and the ability to work in a team;
- a keen interest in research and the field of marine and aquatic sciences;
- a good working knowledge of statistical analyses would be beneficial (e.g. R).

Fixed-term contract: 4 years (or 5 years on a 0.8fte basis).

- you will be appointed for an initial period of 18 months, after which your performance will be evaluated. If the evaluation is positive, the contract will be extended by 2.5 years
- you will be classified as a PhD candidate in the Dutch university job-ranking system (UFO).
the gross starting salary amounts to €2,222 per month, and will increase to €2,840 in the fourth year

Radboud University

Strategically located in Europe, Radboud University is one of the leading academic communities in the Netherlands. A place with a personal touch, where top-flight education and research take place on a beautiful green campus in modern buildings with state-of-art facilities.

Faculty of Science

You will join a team of two other PhD candidates led by Dr Verberk studying the thermal biology of ectotherm animals. Wilco Verberk’s research group at the Animal Ecology and Physiology department aims to understand the physiological basis underlying variation in life history across species. Much work has focussed on how ectotherm animals deal with thermal challenges and whether thermal responses (e.g. with respect to growth, survival and population persistence) can be understood from an oxygen perspective. We primarily take a whole-animal perspective (studying for example metabolism, growth and survival) but combine this approach with field data and with more in-depth measurements (e.g. metabolites and cellular architecture). These thermal responses will be used to gain more insight into the physiology underpinning key life-history trade-offs that give rise to the slow-fast lifestyle continuum.

No commercial propositions please.