3 research outputs found
日韓自動車産業の中国展開
Rate limitation due to encounters is fundamental to many ecological
interactions. Since encounter rate governs reaction rates, and thus,
dynamics of systems, it deserves systematic study. In classical
population biology, ecological dynamics rely on the assumption of
perfectly mixed interacting entities (e.g., individuals, populations,
etc.) in a spaceless world. The so-called mean field assumption
assumes that encounter rates are driven exclusively by changes in the
density of the interacting entities and not on how they are
distributed or move in space. Therefore, the mean field assumption
does not give any insight into relevant spatiotemporal statistical
properties produced by the trajectories of moving entities through
space. In the present study, we develop spatially explicit
simulations of random walking particles (i.e., Lévy walkers) to
evaluate encounter rate constraints beyond the mean field
assumption. We show that encounter rate fluctuations are driven not
only by physical aspects such as the size or the velocity of the
interacting particles, but also by different motion patterns. In
particular, superdiffusion phenomena might be relevant at low
densities and/or low spatial dimensionality. Finally, we discuss
potential adaptive responses of living organisms that may allow
individuals to control how they diffuse through space and/or the
spatial dimensions employed in the exploration process
Superdiffusion and encounter rates in diluted, low dimensional worlds
10 páginas, 3 figuras.Rate limitation due to encounters is fundamental to many ecological
interactions. Since encounter rate governs reaction rates, and thus, dynamics of
systems, it deserves systematic study. In classical population biology, ecological
dynamics rely on the assumption of perfectly mixed interacting entities (e.g.,
individuals, populations, etc.) in a spaceless world. The so-called mean field
assumption assumes that encounter rates are driven exclusively by changes in
the density of the interacting entities and not on how they are distributed or
move in space. Therefore, the mean field assumption does not give any insight
into relevant spatiotemporal statistical properties produced by the trajectories of
moving entities through space. In the present study, we develop spatially explicit
simulations of random walking particles (i.e., L´evy walkers) to evaluate encounter
rate constraints beyond the mean field assumption. We show that encounter
rate fluctuations are driven not only by physical aspects such as the size or the
velocity of the interacting particles, but also by different motion patterns. In
particular, superdiffusion phenomena might be relevant at low densities and/or
low spatial dimensionality. Finally, we discuss potential adaptive responses of
living organisms that may allow individuals to control how they diffuse through
space and/or the spatial dimensions employed in the exploration process.This study was
supported by funds provided by DARPA (HR0011-05-1-0057) and the Andrew W. Mellon Foundation.
FB’s work was also supported by a postdoctoral fellowhip from the Spanish Government (EX-2005-
1011) and the National Science Foundation (DEB-0083566).Peer reviewe