Currently, over 50% of the world’s population lives in urban areas. By 2050, this estimate is expected to be 70%. This urban growth, however, is not uniformly distributed around the world. The majority of it will occur in developing nations and create megacities whose populations exceed at least 10 million people. Not all urban areas, however, are growing. Some are actually losing populations b...

Roberta L. Millstein Department of Philosophy University of California, Davis Davis, CA, USA [email protected] Abstract Biologists studying ecology and evolution use the term “population” in many different ways. Yet little philosophical analysis of the concept has been done, either by biologists or philosophers, in contrast to the voluminous literature on the concept of “species.” This is...

Recently, ecology has shown a strong interest in network theory. The question, as with any other emerging field, is to what extent we are making real progress in understanding ecological and evolutionary processes or just telling the same stories with fancy new words. I first present a biased overview of the development of network theory, focusing on its search for common patterns across seemin...

social network theory, we examine how the structure of relations among organizational populations affects differences in rates of foundings across geographic locales. We hypothesize that symbiotic and commensalistic interpopulation relations function as channels of information about entrepreneurial opportunities and that differing access to such information influences the founding rate. Empiric...

Patchiness has been increasingly recognized by ecologists as a ubiquitous phenomenon in nature. Therefore, substantial research has been directed at modeling the dynamics of metapopulations in patchy habitat settings (e.g., den Boer, 1968; Levins, 1969, 1970; Levins and Culver, 1971; Roff, 1974a,b; Levin, 1976b, 1978; Hastings, 1982, 1991; Hanski, 1983, 1985, 1991; Fahrig and Merriam, 1985; DeA...

Development issues in developing countries belong to complex situations where society and environment are intricate. However, such sites lack the necessary amount of reliable, checkable data and information, while these very constraining factors determine the populations' evolutions, such as villagers living in Sahelian environments. Beyond a game-theory model that leads to a premature selectio...

It is a well known fact that the local stability of an equilibrium point in a system of ordinary differential equations doesnot necessarily imply its global stability. However, the usual methods used in the analysis of stability of equilibrium points in population models establishes only local stability. The restriction to sufficiently small perturbations of the initial conditions frequently ru...

Aaron M. Ellison Harvard University, Harvard Forest, PO Box 68, Petersham, MA, USA E-mail: [email protected] Abstract Bayesian inference is an important statistical tool that is increasingly being used by ecologists. In a Bayesian analysis, information available before a study is conducted is summarized in a quantitative model or hypothesis: the prior probability distribution. Bayes Theo...

For a population with any given number of types, we construct a new multivariate Moran process with frequency-dependent selection and establish, analytically, a correspondence to equilibrium Lotka-Volterra phenomenology. This correspondence, on the one hand, allows us to infer the phenomenology of our Moran process based on much simpler Lokta-Volterra phenomenology, and on the other, allows us ...

based on mathematical equations, are hampered by the qualitative nature of ecological knowledge. In this article, we demonstrate that qualitative reasoning provides alternative and productive ways for ecologists to develop, organize, and implement models. We present a qualitative theory of population dynamics and use this theory to capture and simulate commonsense theories about population and ...