rand.neutral

0th

Percentile

Random neutral ecosystem

Given the size of the metacommunity $J$, and the fundamental biodiversity number $theta$, generate an object of class count using a stochcastic mechanism consistent with the neutral theory.

Keywords
math
Usage
rand.neutral(J, theta=NULL, prob.of.mutate=NULL, string = NULL, pad = FALSE)
Arguments
J
Size of metacommunity
theta
Fundamental biodiversity number $theta$. User must supply exactly one of theta and prob.of.mutate.
prob.of.mutate
Probability of mutation $nu$: $theta=2*J*nu$.
string
String to add to species names. By default (ie string being NULL), species are named “1”, “2”,$...$. Argument string supplies a prefix for these species names; a good one to use is “spp.”. This argument is useful because printing a count object can be confusing if the species names are all integers.
Boolean, with default FALSE meaning to return a count object having only extant species, and TRUE meaning to pad the count with extinct species to J species. Use this when a vector of length J is required consistently (see examples section).
Details

Uses the simulation method on page 289 of Hubbell (2001).

Note

If pad is TRUE, and you set string to “extinct”, things will break.

References

S. P. Hubbell 2001. “The Unified Neutral Theory of Biodiversity”. Princeton University Press.

untb

• rand.neutral
Examples
rand.neutral(1000, 9)
rand.neutral(1000, 9, string="spp.")

data(butterflies)
rand.neutral(no.of.ind(butterflies), optimal.theta(butterflies),string="spp.")

# what is the distribution of abundance of the second ranked species if
# J=10, theta=0.7?