The next step in the understanding of the genome organization, after the determination of complete sequences, involves proteomics. The proteome includes the whole set of protein-protein interactions, and two recent independent studies have shown that its topology displays a number of surprising...

Many complex systems can be described in terms of networks of interacting units. Recent studies have shown that a wide class of both natural and artificial nets display a surprisingly widespread feature: the presence of highly heterogeneous distributions of links, providing an extraordinary...

A model of biological morphogenesis is presented. The model is based in a gene-network cell description plus the interaction among cells. Here interactions between nearest cells are due to diffusion-like mechanisms and also to inductive, cell-to-cell interactions. The gene network properties are...

The Santa Fe Artificial Stock Market [13, 4] is an agent-based artificial model in which agents continually explore and develop expectational models, buy and sell assets based on the predictions of those models that perform best, and confirm or discard these models based on their performance...

In financial markets an excess of buying tends to drive prices up, and an excess of selling tends to drive them down. This is called market impact. Based on a simplified model for market making, it is possible to derive a unique functional form for market impact. This can be used to formulate a...

In this paper we study a simple learning paradigm for iterated normal form games in an evolutionary context. Following the decision theoretic concept of satisficing we design players with a certain aspiration level. If their payoff is below this level, they change their current action, otherwise...

Biogenesis and Evolution are viewed from the perspective of the universality of the metabolic chart with respect to primary metabolism and the phylogenetic specificity of secondary metabolism. This analysis is developed within the context of the evolution of the universal ancestor through...

The immune system uses many strategies to generate its enormous repertoire of diverse antibodies, but their relative importance is not understood. As part of a larger project to quantify their relative contributions, we have studied how the survival probability of an individual scales with the...

Development is the usual arena of evolutionary change in morphology, and much of evolution obviously depends on it. It is very common, however, for discussions of human evolution and developmental change to focus on individual characters (brain size, body weight, bipedalism, etc.). This...

We review recent work aimed at modelling species extinction over geological time. We discuss a number of models which, rather than dealing with the direct causes of particular extinction events, attempt to predict overall statistical trends, such as the relative frequencies of large and small...