
Creates animated plots of two famous abundance models from ecology; the Lotka-Volterra competition and exploitation models
anm.LVcomp(n1, n2, r1, r2, K1, K2, a2.1, a1.2, time = seq(0, 200), ylab =
"Abundance", xlab = "Time", interval = 0.1, ...)anm.LVexp(nh, np, rh, con, p, d.p, time = seq(0, 200), ylab = "Abundance",
xlab = "Time", interval = 0.1, circle = FALSE, ...)
anm.LVc.tck()
anm.LVe.tck()
Initial abundance values for species one. To be used in the competition function anm.LVcomp
, i.e.,
Initial abundance values for species two in the competition function, i.e.,
Maximum intrinsic rate of increase for species one, i.e.,
Maximum intrinsic rate of increase for species two in the competition model anm.LVcomp
, i.e.,
Carrying capacity for species one, i.e.,
Carrying capacity for species two, i.e.,
The interspecific effect of species one on species two, i.e., the term
The interspecific effect of species two on species one, i.e., the term
Initial abundance values for the host (prey) species. To be used in the the exploitation model anm.LVexp
, i.e., the term
Initial abundance values for the predator species in the the exploitation model, i.e., the term
The intrinsic rate of increase for the host (prey) species, i.e., the term
The conversion rate of prey to predator, i.e., the term
The predation rate, i.e., the term
The death rate of predators, i.e., the term
A time sequence for which competition or exploitation is to be evaluated.
Y-axis label.
X-axis label.
Animation speed per frame (in seconds).
Logical, if TRUE
a circular representation of the relation of prey and predator numbers is drawn.
Additional arguments from plot
.
The functions return descriptive animated plots
The Lotka-Volterra competition and exploitation models require simultaneous solutions for two differential equations. These are solved using the function rk4
from odesolve
.
The interspecific competition model is based on:
where
The exploitation model is based on:
where
The term anm.LVe.tck
and anm.LVc.tck
.
Molles, M. C. (2010) Ecology, Concepts and Applications, 5th edition. McGraw Hill.
Crawley, M. J. (2007) The R Book. Wiley
# NOT RUN {
#---------------------- Competition ---------------------#
##Species 2 drives species 1 to extinction
anm.LVcomp(n1=150,n2=50,r1=.7,r2=.8,K1=200,K2=1000,a2.1=.5,a1.2=.7,time=seq(0,200))
##Species coexist with numbers below carrying capacities
anm.LVcomp(n1=150,n2=50,r1=.7,r2=.8,K1=750,K2=1000,a2.1=.5,a1.2=.7,time=seq(0,200))
#----------------------Exploitation----------------------#
#Fast cycles
anm.LVexp(nh=300,np=50,rh=.7,con=.4,p=.006,d.p=.2,time=seq(0,200))
# }
Run the code above in your browser using DataLab