levins {primer} | R Documentation |
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 <HStevens@muohio.edu>
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')
[Package primer version 1.2.0 Index]