Student projects
Students that are interested in plant - pollinator interactions are very welcome to do a project under my and Peter Klinkhamers' supervision (both bachelor and master level). The work can be observational at the community level in combination with simple theoretical modelling or experimental with a small subset of species. Don't hesitate to contact me for more detailed information (see Contact). Field work and experiments can be done preferably in the dunes in Meijendel (The Netherlands, April - September), but it is in principle also possible to do a project in Spain (February - May) or Colorado (June - August). Fieldwork in Spain or Colorado will last between 4 and 8 weeks. For a study in Spain or Colorado we have to find funding (e.g. LUF). For a project in Colorado an application has to be written by me and the student and this has to be accepted by the RMBL (housing possibilities e.g.).
Bachelor / Master project with fieldwork
Rocky Mountains
Summer 2010
Interaction patterns in plant – pollinator networks:
Butterflies
and their nectar plants
Supervision:
Martina Stang (Postdoctoral
researcher)
Peter Klinkhamer (Section leader)
Time of student project in Leiden:
6 to 9 months
between April and December 2010
Field work in USA:
8 to 12 weeks (between June and
August 2010)
Place field work:
Rocky Mountain Biological Laboratory (Crested Butte,
Colorado, USA)
For further information please contact
Martina Stang
before 1st of February 2010
(because
of housing assignment at RMBL, raising of money)
Sylvius gebouw, room 3.5.6b,
Tel: 071 527 5114
email: m.stang@biology.leidenuniv.nl
Overall background: Understanding interaction patterns between flowers and pollinators at the level of whole communities is important for biodiversity conservation because species form a complex web of interactions. A change in species composition due to climate change, invasive species and species loss might change the interaction patterns of the plants and animals and thus influence the stability of the whole community. Community, food web and network theories provide a framework to characterize the overall patterns of interaction (e.g. the degree of generalization or specialization of the species), but there is still a need to better understand the mechanisms that determine these patterns in order to predict the potential consequences of species change and loss.
Specific project background: Who visits whom can be explained surprisingly well by the combination of two general mechanisms. First, the nectar that the pollinators search for in flowers is often deeply hidden, and only pollinators with tongues longer than the threshold set by nectar depth will bother to visit such a flower. Second, the visitors to a given flower type will be a representative sample of all insect species with long enough tongues, and will reflect the relative abundances of these species (Stang et al. 2006, 2007, 2009). Simple probabilistic models based on these mechanisms are able to predict which kind of species interact, but they are not able to predict how often the interactions occur (visitation frequency). In this project we are searching and testing factors that will predict flower visitation frequency of butterflies. Beside nectar depth and abundance we will include resource availability (nectar production rate) and resource requirements (based on body mass). Optimal foraging theory, allometric scaling laws, and size and number trade-offs form the theoretical background for choosing these factors.
Project description: There are three main questions: (1) Do large butterflies visit more plant species than small ones? (2) Do large butterflies visit flowers faster and more often than small butterflies? (3) Do the preferred nectar plants have few, large and nectar rich flowers or many, small and nectar poor flowers? The student will study the butterflies and their nectar plants in a dry meadow community. The analysis of the data will be mainly based on regression analysis. The results of the student project will be incorporated as scaling factors in the probabilistic models. With the model the consequences of species loss for the reproductive success of the species and the stability of the whole community will be predicted more realistically than it is up to now possible.
Practical information: The RMBL is a famous field station in an old miner’s village at 3000 m in the Colorado Rocky Mountains visited by scientists and their students from all over the US. The fieldwork can be done alone or in a team of two to three people (one student from Leiden, one or two students from the US and Martina Stang). The collaborators of the project in the US are Nickolas Waser and Mary Price (University of Arizona and RMBL). The potential student will have the unique chance to exchange experiences with the students from the undergraduate research program, who are doing a variety of ecological research projects at the field station (see website), and to join seminars. The costs of the stay at RMBL and travelling can be funded (the proposals for LIFS / RMBL have to be written in March, we can help). The research meadows are in walking distance from the cabins so no driving license is needed. Please plan 2 months for writing project proposal (April to May), 2 to 3 months field work, 2 to 4 months data analysis and writing (September to December).
Costs: 1280 to 2970 Euro (10 weeks, depending on cabin, meal plan choice etc.) + 900 Euro (flight), funding possibilities for about 2000 - 2500 Euro: LISF, RMBL (deadlines: 30th of March)
Literature: Martina Stang; Peter G. L. Klinkhamer; Nickolas M. Waser; Ingo Stang; Eddy van der Meijden (2009) Size-specific interaction patterns and size matching in a plant-pollinator interaction web, Annals of Botany 2009; doi: 10.1093/aob/mcp027 PdF
Former Projects:
Kirsten Kaptein: “Can blossom complexity predict the diversity of flower visitors in a Mediterranean vegetation type” (February - May 2003), University of Leiden, Institute Biology Leiden (IBL), Section Plant Ecology Abstract
Kirsten Kaptein
Vera Geluk: “The relationship between size parameters of blossoms and their visitors in a Mediterranean plant- and insect community” (February - May 2003), University of Leiden, Institute Biology Leiden (IBL), Section Plant Ecology
Vera Geluk (in front) and Manja Kwak (right)
Melissa Pickett: “The relationships among butterfly size, visitation rate, handling time, and floral display size” (June - August 2009), RMBL, Colorado, USA
Abstract: Kirsten Kaptein: “Can blossom complexity predict the diversity of flower visitors in a Mediterranean vegetation type”
The aim of this study is to predict
the diversity of flower visitors on basis of floral characteristics. There
have been several attempts to classify blossoms in relation to the aim
of this study. A new attempt is the use of an index of blossom complexity.
Blossom complexity is a measure of blossom functioning in relation to guiding
and restriction of flower visitor movements and precision of pollen deposition
on the visitors. The relationship between the index of blossom complexity
and the number of species has been tested in the dunes of Meijendel, The
Netherlands. A negative linear relationship between blossom complexity
and the number of species has been found there. In this study we tested
the same relationship in a Mediterranean vegetation community in the south
east of Spain.
In the selected study area we have studied 15 out of the 26 occurring flowering
plant species, throughout the whole spectrum of complexity. Each plant species
was observed for four times 15 minutes spread over the whole day. During that
time all the visitors were scored for what they fed on and were caught to determine
the body- and tongue-length. The visitors were then divided into visitor guilds.
On the 15 observed plant species we found in total 108 insect species visiting
the flowers, 51 functional morphological classes and 64 taxonomic morphological
classes.
Regressions showed a negative linear relationship between blossom complexity
and visitor diversity. This has been found whether diversity was measured as
the number of species (R²=0,38), the number of visitor guilds based on function
and size (R²=0,316) or the number of visitor guilds based on taxonomy and size
(R²=0,352). The easiest way to predict the diversity of flower visitors
is to use taxonomic morphological classes. This is because the insect order of
a visitor (taxonomy) is much easier to determine in the field than its species
name or feeding behaviour.
The relationship between blossom complexity and the diversity of flower visitors
in Alicante is almost the same as the relationship in Meijendel. This gives an
indication that the index of blossom complexity is broadly applicable.