Gregor Rolshausen, PhD

Redpath Museum & Dept. of Biology McGill University
859 Sherbrooke Street West
H3A2K6 Montreal, Quebec
tel. +1-514-398-4086 ext 00714
gregor.rolshausen @ mail.mcgill.ca

• Contemporary local adaptation and phenotypic divergence
• Establishment/Reversal of reproductive barriers
• Incipient isolation events
• Parallel evolution
• Evolution of signals in (plant-)animal communication
  

Current

• Microevolutionary consequences following oil contamination
  I recently joined the Lab of Andrew Hendry to study Guppies (Poecilia reticualta) and killifish (Rivulus hartii) that dwell in oil contaminated streams in southern Trinidad.
  
  My three major research goals are: (1) To investigate how eco-toxins (i.e. crude oil pollution) drive contemporary local adaptation, reproductive isolation, and diversification in natural populations. (2) To distinguish 'plastic' from 'microevolutionary' responses driven by human-induced pollution. (3) To determine the extent to which local adaptation in response to pollution occurs in parallel between different populations from the same species (guppies) and between two different species (guppies vs. Killifish)? To approach these questions I combine experimental field studies, lab assays, genetic analyses and statistical tools.
  
  Anthropogenic disturbance is a potent agent of evolution driving substantial life history changes and phenotypic divergence in affected species often exerting stronger selection coefficients than in natural contexts. Assessing how humans alter (micro-)evolution in wild populations represents a tremendous scientific challenge and the guppies and killifish from Trinidad are a very interesting opportunity to gain more insight into this important concern.
  
  Supervisor & Collaborators: Andrew Hendry (McGill), Paul Bentzen (Dalhousie University), Subhasis Goshal (McGill), Dawn Phillip (University of West Indies), Chris Harrod (Belfast University)
  
  Funding Organisation: DAAD, PostDoc Stipend
  

Former

• Reproductive isolation and population divergence along migratory divide
  For my PhD thesis I studied migratory birds to investigate contemporary microevolution following a recent migratory divide.
  
  Migratory divides are contact zones between populations with distinct migratory orientations. Like hybrid zones migratory divides provide exceptional insights into processes involved in adaptive divergence and reproductive isolation along ecological gradients. One particularly impressive example is the migratory divide in central European blackcaps (Sylvia atricapilla).
  
  Supervisor & Collaborators: H.Martin Schaefer (University of Freiburg), Gernot Segelbacher (University of Freiburg), Keith Hobson (Environment Canada)
  
  Funding Organisation: Deutsche Forschungsgemeinschaft DFG grant
  
  
• Evolution of signals in (plant-)animal communication systems
  
  Fruit-frugivore interactions and secondary plant compounds
  
  Anthocyanins are plant pigments responsible for the reddish and violet colours of various plant structures and play a major role in attracting pollinators and seed-dispersers. Because they link both, the visual signal character and the beneficial role for consumers, anthocyanins in fruits are a very interesting research basis for the evolution of signals in frugivore-systems.
  
  I studied frugivory in migrating Blackcaps with different overwintering habitats. Research interests were the impact of different winter diets on health status.
  
  Signalling systems in plant-herbivore interaction
  
  During my Diploma thesis I explored the hypothesis that plants can signal there defence strength to herbivores visually. In particular I scrutinised autumnal leaf colouration as a potential honest signal of defensive strength in the mountain ash (Sorbus aucuparia).
  

• Rolshausen G., Segelbacher G., Hobson K.A., Schaefer, H.M. (in prep). Distance in stable isotope signature relates to genetic distance along a migratory divide.
• Rolshausen G., Hobson K.A., Schaefer H.M. (2010) Spring arrival along a migratory divide of sympatric blackcaps (Sylvia atricapilla). Oecologia 162 (1): 175-183.
• Rolshausen G., Segelbacher G., Hobson K.A., Schaefer, H.M. (2009) Contemporary evolution of reproductive isolation and phenotypic divergence in sympatry along a migratory divide. Current Biology 19 (24): 2097-2101.
• Segelbacher G., Rolshausen G., Weis-Dootz T., Serrano D., Schaefer H.M. (2008) Isolation of ten tetranucleotide microsatellite loci in the blackcap (Sylvia atricapilla). Molecular Ecology Ressources 8: 1108-1110
• Schaefer H.M., Rolshausen G. (2007) Reply. How to investigate a putative signal? Stick to the right method when assessing the response of a receiver. Biology Letters 3: 152-153.
• Rolshausen G., Schaefer H.M. (2007) Do aphids paint the tree red? Can herbivore resistance or photoprotection explain colourful leaves in autumn? Plant Ecology 191: 77-84.
• Schaefer H. M., Rolshausen G. (2007) Aphids do not attend leave colour as handicap signal, but to the handicap of reproductive investment. Biology Letters 3: 1-4
• Schaefer H. M., Rolshausen G. (2006) Do alternative hypotheses evoke 'red alert' among co-evolutionists. BioEssays 28: 960-961.
• Schaefer H. M., Rolshausen G. (2006) Plants on red alert – do insects pay attention? BioEssays 28 (1): 65-71.