Null models and dispersal distributions: a comment on an article by Caley
Article Abstract:
A null model for dispersal distributions against which an empirical data is to be compared is suggested by Caley. Caley presents Waser's geometric model which proposes that individuals dispersing from their place of birth move in a straight line and settle in the first unoccupied territory. The distribution of dispersal distances follows a geometric distribution if the unoccupied sites occur independently at random. The data on individual dispersal behavior includes the distribution of occupied and unoccupied sites and the direction in which the individual is moving. Caley's suggestion is that when Waser's model is applied a null model should also be fitted to determine which provides the description of the data. The fitting of the null model reveals that the population-level distance-specific steeling rate decreases with an increase in distance, though at the individual level it is a constant.
Publication Name: The American Naturalist
Subject: Earth sciences
ISSN: 0003-0147
Year: 1993
User Contributions:
Comment about this article or add new information about this topic:
The analysis and interpretation of seedling recruitment curves
Article Abstract:
Statistical techniques suitable for the interpretation of seedling recruitment data are presented. Application of the methods on a data collection indicate that seed banks do notexhibit a negative exponential decay pattern and that a number of recruitment models exist. Recruitment patterns that are age-specific are particularly difficult to interpret because of individual variation in viability and unobserved mortality. A model describing the recruitment process is developed.
Publication Name: The American Naturalist
Subject: Earth sciences
ISSN: 0003-0147
Year: 1993
User Contributions:
Comment about this article or add new information about this topic:
Plant outliers: an ecogenetic perspective
Article Abstract:
A study of the reproductive biology of outliers and of rare plants reveals that they produce lesser seeds per flower than plants within local populations but are capable of interbreeding over long distances. Outliers from large gatherings of interbreeding plants are the major sources of extrinsic pollen and seeds, disturbing the spacing of local populations forming the nuclei for new populations. Outliers serve as interpopulation links for pathogens and herbivores.
Publication Name: The American Naturalist
Subject: Earth sciences
ISSN: 0003-0147
Year: 1995
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Path modeling methods and ecological interactions: a response to Grace and Pugesek. Assembly rules: desert rodent communities are structured at scales from local to continental
- Abstracts: Testing the marine and continental fossil records: comment and reply. Middle Cretaceous reef collapse linked to ocean heat transport: comment and reply
- Abstracts: The phylogenetic component of cooperative breeding in perching birds: a commentary. Comparative analyses of phylogenetic effects in the life-history patterns of iguanid reptiles
- Abstracts: An empirical study of the economic effects of climate change on world agriculture. Societal adaptation to climate variability and change: an introduction
- Abstracts: Broad-terrane Jurassic flood basalts across northeastern North America: comment and reply. Jurassic paleopole controversy: contributions from the Atlantic-bordering continents