Publikationsserver der RWTH Aachen University
Seed dispersal by ants and its consequences for the phenology of plants : a study system for mutualistic animal plant interactions
Abstract
dc:descriptionThe hypothesis was tested that ant dispersed plant species are adapted to the seasonal variation in ant activity, i.e. that ant dispersed plant species produce ripe fruits when the activity of their seed dispersers is especially high. Two testable predictions of this hypothesis exist: 1. Ant dispersed and differently dispersed plant species differ in their seasonal development, i.e. ant dispersed plant species fruit (flower) earlier or later in the year than other plant species. Floristic investigations yielded ant dispersed plant species to flower and fruit 1.5-2 month earlier than non-ant dispersed plant species. Since other factors such as growth form, seed size or pollination mode may have caused this seasonal difference, multivariate analyses were performed. The results demonstrated that these additional factors had only little influence on the seasonal difference and that the effect was mainly due to the mode of seed dispersal. 2. At times when ant dispersed plant species produce ripe fruits the ant activity must be higher than at times when non-ant dispersed plant species do. Investigations of seasonal frequencies of ant individuals and of seasonal seed removal rates revealed ant activity to be especially high from May to July. Mean fruiting time of ant dispersed plant species was the beginning of July. Mean fruiting time of non-ant dispersed plant species was end of August / beginning of September. Statistical tests revealed that if ant dispersed plants had fruited as late as the other plants, they would have suffered a significant loss in seed removal. These results support the hypothesis drawn up in the beginning. The early fruiting times of ant dispersed plants appear to be an adaptation to the seasonal variation in ant activity.
Degree
thesis:*- Grantor dc:publisher
- Publikationsserver der RWTH Aachen University
- Year dc:date
- 2000
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Oberrath, Reik
- Contributors dc:contributor
-
- Böhning-Gaese, Katrin
Subjects
dc:subject × 6Rights
dc:rights- Statement dc:rights
-
- info:eu-repo/semantics/openAccess
- Language dc:language
- eng
Identifiers
dc:identifier.*- OAI identifier oai:identifier
- oai:publications.rwth-aachen.de:60043