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which is the basic equation of population dynamics. If the survivorship and fecun- dity schedules hold constant, the population’ ...
As we saw earlier in this chapter, the geometric model can be readily translated into the exponential model: Nt=N 0 ert Hence, i ...
Dispersal, dispersion, and distribution 7 This chapter explores some of the reasons why populations are found where they are. We ...
the juveniles leave voluntarily, their behavior being innately determined by their genes (e.g. in Belding’s ground squirrels (Sp ...
polygynous species, females invest more in each offspring than do males, and so their reproductive success is determined by reso ...
does not arise because no quadrats are involved, but no simple measure is presently available for distributions of distances tha ...
by an upper and lower limiting temperature but it is demarcated within those bounds by rainfall whose effect varies with tempera ...
winter. Only four North American species can withstand the cold to reside year round in the Arctic: the raven (Corvus corax), th ...
influenced by soil type, soil fertility, vegetation cover, and distribution of water (Parer 1987). High temperatures are often c ...
Perhaps not apparent at first sight is the restricted availability of water for wildlife in cold regions. Not only are many of t ...
the middle of the wet season 9 months after the previous rains; but both occur when the swamp grasslands are most available. So ...
and morphological varieties that differ from central populations (Lesica and Allendorf 1995). Many species of wildlife have been ...
For this kind of random walk model, most trajectories tend to find their way back to a position not far from the initial startin ...
∆Nx=Nx,t+ 1 −Nx,t=− 2 dNx,t+dNx−1,t+dNx+1,t We then rearrange terms on the right-hand side of the equation: ∆Nx=d[(Nx−1,t−Nx,t) ...
displacements for all individuals, and divides this sum by the total sample size to estimate mean-squared displacement. Dis then ...
the density gradient, which we have already suggested fuels a high rate of diffusion. The net result is a population that explod ...
disperser, changes in disperser motivation, or heterogeneous environmental effects on dispersal tendency (Turchin 1998). Nonethe ...
The first term represents colonization of new sites, and the second term represents extinction. Provided that c>e, this model ...
Well-studied examples of metapopulation dynamics in vertebrates are less com- mon. Long-term studies of pool frogs along the coa ...
abound in the natural history literature, as we discuss in Chapter 18. The importance of habitat loss may be magnified in the fu ...
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