We have analyzed the base-pair probability distribution of 16S and 16S-like and 23S and 23S-like ribosomal RNAs of Archaea, Bacteria, chloroplasts, mitochondria and Eukarya, as predicted by the partition function approach for RNA folding (McCaskill, 1990). A quantitative analysis of the...

Although mass extinctions probably account for the disappearance of less than 5% of all extinct species, the evolutionary opportunities they have created have had a disproportionate effect on the history of life. Theoretical considerations and simulations have suggested that the empty niches...

A particular class of ordinary differential equations (ODE) describing catalyzed, template-induced, and erroneous replication is investigated. The ODEs can be split into a replicator part accounting for the correct replication and a mutation term accounting for all miscopying processes. The set...

The dynamics of a network of autocatalytically replicating species in a continuously stirred tank reactor can be described by a replicator equation in the limit of small flux rates.

The collapse of ancient societies such as the Mesa Verde-region pre-Hispanic Pueblos has puzzled generations of scientists. Many explanations for particular cases have been suggested, from combinations of social, political and economic factors (Tainter 1988), to climatic factors such as drought....

In a recent publication (Bergman et al., 1995) we used a diploid version of the NK model of fitness landscapes (Kauffman and Levin, 1987; Kaufman, 1989) to investigate properties of Wright's shifting balance theory of evolution (reviewed in Wright, 1977). The NK model is a relatively simple way to...

We study percolation on small-world networks, which has been proposed as a simple model of the propagation of disease. The occupation probabilities of sites and bonds correspond to the susceptibility of individuals to the disease and the transmissibility of the disease respectively. We give an...

This paper examines how web design firms in the emergent new media industry probe and experiment with possible forms and sources of value giving shape to the new economy. Focussing on the collaborative engineering of cross-disciplinary web-design project teams, we examine how websites emerge as...

A recent spate of writings has argued that in a fundamental sense, science is reaching limits. The basic claims of this work is twofold. First, it is argued that for many areas of inquiry, notably physics, chemistry, and biology, science has provided an essentially accurate view of nature. The...

We demonstrate the existence of a phase transition in combinatorial optimization problems. For many of these problems, as local search algorithms are parallelized, the quality of solutions first improves and then sharply degrades to no better than random search. This transition can be...