Evol Ecol Res 3: 37-50 (2001)     Full PDF if your library subscribes.

Advantages of seed dispersal: A re-evaluation of directed dispersal

Daniel G. Wenny*

Illinois Natural History Survey, Savanna Field Station, 3159 Crim Drive, Savanna, IL 61074, USA


e-mail: dwenny@inhs.uiuc.edu

ABSTRACT

Seed dispersal can be advantageous (1) in escape from density- or distance-dependent seed and seedling mortality, (2) by colonization of suitable sites unpredictable in space and time, and (3) by directed dispersal to particular sites with a relatively high probability of survival. Most previous research on the consequences of seed dispersal has focused on escape and colonization because adaptations ensuring directed dispersal are not expected under the paradigm of diffuse mutualism that characterizes the modern view of seed dispersal evolution. In this paper, I suggest that directed dispersal is more common than previously believed even in the absence of plant adaptations to promote it. Directed dispersal may be seen in particular among animal-dispersed plants and in arid ecosystems or successional areas, but has been overlooked due to the lack of detailed data on seed shadows generated by particular species, and the fact that the alternative advantages of dispersal are not mutually exclusive. Although directed dispersal is never thought to be the only advantage of dispersal, it may often be ecologically important if one dispersal vector has a disproportionate effect on plant recruitment. Furthermore, in human-disturbed and managed ecosystems, directed dispersal may be important in restoration. More studies detailing the consequences of different patterns of seed dispersal will be useful for conservation and management strategies.

Keywords: colonization, directed dispersal, dispersal quality, escape, nurse plants, recruitment foci, safe sites, seed dispersal, seed shadow.

DOWNLOAD A FREE, FULL PDF COPY
IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.

 

        © 2001 Daniel G. Wenny. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.