Animal Sciences & Health
Behaviour and Cognition
Understanding the behaviour of animals and humans involves understanding of its function, evolution, and underlying mechanisms. We explore these mechanisms at and across different levels, from gene expression to cognitive processes. We use an explicitly integrative approach, reflected in interdisciplinary collaborations. Our focus is on the analysis of acoustic communication and the effects of anthropogenic noise on the functioning and health of animals.
Acoustic communication: from birdsong to language
Sound plays a crucial role in the lives of many animals. It is used for primary needs such as finding prey or avoiding predators but also for complex communication as in our own language. To understand mechanisms, form, function and evolution of the diverse acoustic communication systems in vertebrate animals, we study acoustic communication in water and in air. We use a combination of laboratory and field studies on a variety of model species, from fish and cetaceans to humans, but birds in particular.
Birdsong is a learned, complex mating signal, with pronounced individual variation. We examine the development of songs, the processes contributing to acoustic variation, the link with personalities and the impact of song variation on mate choice. We also address the evolution of songs and singing, and the causes and consequences of signal change. Through this model system, we gain understanding of fundamental processes like sexual selection and speciation and how learning affects trait evolution.
Birdsong is also considered to be the closest animal analogue of human speech and language. Comparative studies address similarities and differences in molecular and cognitive mechanisms involved in vocal learning and in the perceptual processing of speech in birds (with zebra finches as the prime model species) and humans. The aim of this work is to provide hypotheses about the mechanisms from which speech and language might have evolved.
Anthropogenic noise: sound in a changing world
The world is getting noisier by the day. A wide variety of noisy construction and traffic activities, on land, at sea and in the air, contribute to increasing sound levels for animals and humans. We examine the impact of anthropogenic noise on birds, fish and marine mammals. We investigate behavioural disturbance, masking effects on communication, causes and consequences of physiological stress, coping styles, and the potentially undermining impact on cognitive functioning and development. The zebrafish and zebra finch serve as indoor model species, but we also do outdoor experiments, on land and in open water. Our aim is to gain fundamental understanding of the impact of noise pollution and to provide science-based, practical advice for policy makers and legislators on monitoring and mitigation measures.
Links to other themes and collaborators
Our studies on vocal development, personality, stress and coping styles are strongly linked to the other themes in the cluster of Animal Sciences & Health. A key example is the interdisciplinary work on behavioural phenotyping and chronobiology using molecular approaches and stress physiology, with zebrafish as model organism. Within the Faculty of Science, the studies on the impact of anthropogenic noise nicely link to the expertise on environmental assessment and conservation at the Centre for Environmental Studies (CML). In the broader context of Leiden University, the studies of avian cognition, and in particular the comparative studies on speech and linguistic processing in birds, contribute to the research profile area “Brain function and dysfunction” and involve interdisciplinary collaboration with linguists and others within the Leiden Institute for Brain and Cognition (LIBC).