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It is argued that a good understanding of population dynamics can lead to a better appreciation of the impact of immigration on niche conservatism at species' borders. It may also promote a deeper understanding of such impact on niche conservatism in any species with populations which would become extinct deterministically in the absence of regular immigration, and which is beyond its current niche due to immigration. A simple one-locus haploid model that considers population dynamics, gene flow and local selection is examined.

Dispersal or the movement between population is favored by chaotic population dynamics in constant but patchy environments. In such systems, subpopulations on different patches with minimally different initial conditions will diverge as their population curves unfold. In the long term, the rank order of geometric growth rate or fitness among patches should vary, even if the environment is constant. A model which illustrates the basic effect of this pattern is presented.

Mathematical analysis shows that in a simple apparent competition model with two prey species and a shared predator, the dominant prey species is that which supports the highest predator density. In a more complex model, in which the two prey species also share the same resource, the dominant species decreases the resource to lower levels and increases the predator to higher levels than that of the other species, assuming that they have equal predation rates. When unequal predation rates are allowed, the rule to be applied depends on the relation between the mass-balance constraints of the two prey species.

Phenotypic and genetic variation in dispersal characters within and among communities and environmental sensitivity of dispersal propensity was quantified in experiments. A two-patch model was studied to analyze how patterns of spatial and temporal variation in carrying capacities affect natural selection on dispersal. A certain amount of dispersal was preferred by selection under most conditions of habitat variability. The system also defined parameters for coexistence of competing species in different environments.

The article announces awards given to the naturalists in 2007 including the Edward Osborne Wilson Award to George Venable, the Sewall Wright Award to Dolph Schluter and the Young Investigator's Prizes to Andy Gardner, Maurine Neiman, Daniel Ortiz-Barrientos and Sander van Doorn.