Overgrowth competition, fragmentation and sex-ratio dynamics: a spatially explicit, sub-individual-based model
Authored by PH Crowley, CR Stieha, DN McLetchie
Date Published: 2005
DOI: 10.1016/j.jtbi.2004.09.017
Sponsors:
United States National Science Foundation (NSF)
Platforms:
MATLAB
Model Documentation:
Other Narrative
Flow charts
Model Code URLs:
Model code not found
Abstract
Sessile organisms that compete for access to resources by overgrowing
each other may risk the local elimination of one sex or the other, as
frequently happens within clumps of the dioecious liverwort Marchantia
inflexa. A multi-stage, spatially implicit differential-equation model
of AT. inflexa growing in an isolated patch,. analysed in a previous
study, indicated that lone-term coexistence of the sexes within such
patches may be only temporary. Here we derive a spatially explicit.
sub-individual-based model to reconsider this interpretation when much
more ecological realism is taken into account, including the process of
fragmentation. The model tracks temporally discrete growth increments in
continuous space, representing growth architecture and the overgrowth
process in significant geometric detail. Results remain generally
consistent with the absence of long-term coexistence of the sexes in
individual patches of Marchantia. Dynamics of sex-specific growth
qualitatively resemble those generated by differential-equation models, suggesting that this much simpler framework may be adequate for
multi-patch metapopulation models. Direct competition between
fragmenting and non-fragmenting clones demonstrates the importance of
fragmentation in overgrowth competition. The results emphasize the need
for empirical work on mechanisms of overgrowth and for modeling and
empirical studies of life history tradeoffs and sex-ratio dynamics in
multi-patch systems. (C) 2004 Elsevier Ltd. All rights reserved.
Tags
growth
Population-dynamics
Size
Coral
Rhizome architecture
Marchantia-inflexa
Cellular
automata
Salvinia-molesta
Desert moss
Survivorship