levins {primer}

Classic Metapopulation Model

Description

A function for the classic metaapopulation dynamics, for use with ode in the deSolve package.

Usage

levins(t, y, parms)

Arguments

t

Argument for time

y

A scalar for the population variable

parms

Vector or list of parameters

Value

Returns a list of length one, for use with ode in the deSolve package.

Component 1

vector of the state variable (a scalar for the proportion of sites occupied).

Author(s)

Hank Stevens <[e-mail]>

References

Levins, R. (1969) Some demographic and genetic consequences of environmental heterogeneity for biological control. Bulletin of the Entomological Society of America, 15, 237–240.

Stevens, M.H.H. (2009) A Primer of Ecology with R. Use R! Series. Springer.

See Also

gotelli, hanski,lande, MetaSim, clogistic

Examples

## The function is currently defined as
function (t, y, parms)
{
    p <- y[1]
    with(as.list(parms), {
        dp <- ci * p * (1 - p) - e * p
        return(list(dp))
    })
  }
library(deSolve)
p <- c(ci=.1, e=.01)
time <- 1:10
initialN <- .3
out <- ode(y=initialN, times=time, func=levins, parms=p)
plot(time, out[,-1], type='l')