EcoVirtual (version 1.1)

simHub: Neutral Theory of Biogeography

Description

Simulates Community Dynamics as in the Neutral Theory of Biogeography

Usage

simHub1(S = 100, j = 10, D = 1, cycles = 10000, m.weights = 1,
  anima = TRUE)
simHub2(S = 100, j = 10, D = 1, cycles = 10000, m = 0.01,
  anima = TRUE)
simHub3(Sm = 200, jm = 20, S = 100, j = 10, D = 1, cycles = 10000,
  m = 0.01, nu = 0.001, anima = TRUE)

Arguments

S

number of species in the community.

j

individuals per species in the metacommunity.

D

number of deaths per cycle.

cycles

number of cycles in the simulation.

m.weights

Mortality weights for each species. Mortality rates of individuals of each species is proportional to species' abundances multiplied by these weights as in Yu et al. (1998). In neutral dynamics all weigths are equal. If length(m.weights)<S then species are divided in groups of (approximately) S/length(m.weights) and species of each group have a value in m.weights. This allows to create groups of species with different mortality probabilities and compare to the neutral dynamics.

anima

logical; if TRUE, the simulation frames of the metacommunity are shown.

m

colonization/immigration rate.

Sm

number of species in the metacommunity.

jm

individuals per species in the metacommunity.

nu

speciation rate.

Value

These functions returns a graph with the number of species in time (cycles) in the metacommunity.

They also return an invisible matrix with the results of species richness on each community per time.

Details

'simHub1' is the model without immigration.

'simHub2' incorporates immigration rate from the metacommunity

'simHub3' incorporates immigration and speciation rates in the metacommunity.

References

Hubbell, S.P. 2001. The Unified Neutral Theory of Biodiversity and Biogeography. Princeton University Pres, 448p.

Yu, D. W., Terborgh, J. W., and Potts, M. D. 1998. Can high tree species richness be explained by Hubbell's null model?. Ecology Letters, 1(3): 193--199.

See Also

extGame, randWalk, http://ecovirtual.ib.usp.br

Examples

# NOT RUN {
# }
# NOT RUN {
simHub1(S=10,j=10, D=1, cycles=5e3)
simHub2(j=2,cycles=2e4,m=0.1)
simHub3(Sm=200, jm=20, S= 10, j=100, D=1, cycles=1e4, m=0.01, nu=0.001, anima=TRUE)
# }
# NOT RUN {
# }