An elementary model of animal aggregation is presented. The gorup size distributions resulting from this model are truncated power laws. The predictions of the model are found to be consistent with data that describe the group size distributions of tuna fish, sardinellas, and African buffalos.<p> <p>...</p></p>

The fossil record of life has been shown to provide evidence for scaling laws in both time series and in some statistical features. This evidence was suggested to be linked with a self-organized critical phenomenon by several authors. In this paper we review some of these models and their...

A new model ecosystem consisting of many interacting species is introduced. The species are connected through a random matrix with a given connectivity . It is shown that the system is organized close to a boundary of marginal stability in such a way that fluctuations follow power law...

The topology of the proteome map revealed by recent large-scale hybridization methods has shown that the distribution of protein-protein interactions is highly heterogeneous, with many proteins having few links while a few of them are heavily connected. This particular topology is shared by...

The dynamics of biological populations often appear quite complex, exhibiting considerable year-to-year variation in local abundances. One approach to dealing with ecological complexity is to reduce the system to one or a few species, for which meaningful equations can be written and even...

Why are some ecosystems so rich, but yet contain so many rare species? High species diversity, together with rarity, is a general trend in neotropical forests and coral reefs. But the origin of such diversity and the consequences of food web complexity in both species abundances and temporal...

In a recent paper, we analysed the dynamics of traffic flow in a simple, square lattice architecture. It was shown that a phase transition takes place between a free and a congested phase. The transition point was shown to exhibit optimal information transfer and wide fluctuations in time, with...

The clustering of dead bodies by ants is simulated, using a cellular automaton model, the rules of which are carefully derived from experiments. Starting from a random spatial distribution of corpses, a cemetery organizes itself into clusters of corpses. The dynamics of clustering can be...

A prominent feature of comparative life histories in the well documented negative correlation between growth rate and life span [1,2]. Patterns of resource allocation during growth reflect life-history differences between species [1,2]. This is particularly striking in tropical forests, where...