J.C. (Jacco) van Rijssel
Associate Researcher, Marine Zoology, Lake Victoria cichlids
- j.c.van.rijssel@biology.leidenuniv.nl
- Phone
- +31 (0)71 527 4503
- Room Number
- Sylvius Building, 6th floor, room 6.5.14a
Courses
2007 Course French, semi-advanced 1, certificate, The Language Academy, University of Amsterdam
2007 Assisstance Integrative Zoology, Leiden University.
2007 Course Laboratory Animal Science (Biomedical Sciences), Leiden University, certificate art. 9.
2006 Ethnobotanical Knowledge Systems, Institute of Environmental Sciences, Leiden (CML), certificate.
Proffesional experience
01/08-09/08 Internship Institute of Environmental Sciences, Leiden (CML)
Lion (Panthera Leo) ecology and livestock conflicts in Waza National Park, Cameroon.
02/07-08/07 Internship Institute Biology Leiden (IBL), section: Behavioural BiologyBlackbird (Turdus merula) song divergence between city and forest: due to anthropogenic noise or density differences?
01/06-07/06 Internship Institute Biology leiden (IBL), section: Integrative ZoologyInfluence of swimming on testis histology of male silver eels (Anguilla anguilla L.)
Research interests
My research interests lay in the ecology and evolution of behavioral and morphological traits in vertebrates, especially fish. My PhD-project focuses on the contemporary morphological changes in Lake Victoria cichlids in the past 30 years. I try to find out over what time period these changes occurred and in relation to which environmental parameters in the lake (e.g. Nile perch predation, DO-levels, food availability). Further, I try to reveal whether or not these changes are due to phenotypic plasticity or genetic changes.
The main focus at the moment is to see which morphological changes have occurred in 6 different (although closely related) Lake Victoria cichlid species. With the use of modern geometric morphometry techniques and digital calipers, outer body morphology is studied. Next to outer body morphology, inner body morphology can give more information about which morphological structures (gills, muscles, pharyngeal jaws) have changed in relation to the ecological changes in the lake. That is why we are studying above mentioned structures (and more) with a three year time interval from 1978 up till now. Common garden experiments with an old (lab) fish and modern (field) cichlids will tell us more about plastic and heritable traits. Therefore hypoxia experiments are part of this research to reveal the genetic and phenotypic plasticity involvement in morphological modifications
Publications
Palstra, A., Schnabel, D., Nieveen, M., van Rijssel, J., de Jong, D., Spaink, H., van den Thillart, G. (2007) Reproductive inhibition in male European eels is less severe than in females as shown by GnRH-stimulation of quantified gonadotropin expression in the pituitary and testis development. European Aquaculture 2007 workshop on European eel reproduction. October 24, Istanbul (Turkey).
Ripmeester, E.A.P., Kok, J.S., van Rijssel, J.C., Slabbekoorn, H.H. (2008) Intra-individual variation in habitat-dependent birdsong divergence: an integrated study on the influence of territory density and ambient noise. Behavioral Ecology and Sociobiology 64:3, 409-418
Fobuzie, P.N., Kok, J.S., van Rijssel, J.C., Buij, R., Croes, B.B., de Iongh, Udo de Haes, H.A.(2010) Threat of rapid extermination of the lion (Panthera leo leo) in Waza National Park, Northern Cameroon. African Journal of Ecology, 48:4, 888-894
Van Rijssel, J.C., Witte, F. (2010) Contemporary morphological changes in Lake Victoria cichlids. Cichlid Science 2010 meeting. August 29, Basel (Switzerland)
Monday, January 24, 2011