Evolution of Complex Density-Dependent Dispersal Strategies

Evolution
Our inspiration
Model
Results
Summary
Evolution of
Complex Density-Dependent Dispersal Strategies
Kalle Parvinen, Anne Seppänen and John Nagy
University of Turku, Finland
Department of Mathematics
[email protected]
Applied Mathematics
seminar 2.3.2012
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Outline
1
Evolution
2
Our inspiration
3
Model
Local model
Metapopulation model
Adaptive dynamics
Example
4
Results
5
Summary
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Example
Theory
Questions
Evolution
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Example
Theory
Questions
Not examples of evolution
butterfly metamorphosis
cell differentiation: osteoclast
[Boyle et al, Nature 2003]
human development
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Example
Theory
Questions
Evolution
The theory of evolution by natural selection assumes:
individuals differ by their trait,
different survival probability
traits are heritable
too many offspring, not all can survive
struggle for existence
Charles Darwin
Individuals that survive and reproduce before dying
(1809-1882)
are on average, better suited to their local
environment
Therefore...
As time passes by the distribution of traits change.
More fitted become more general: Adaptation
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Example
Theory
Questions
Evolution
Some questions:
Why nature is green?
Why multicellular organism evolved?
Why helping behavior evolved?
Why we have two genders?
Why senescence?
Why dispersing evolved?
Can we prevent evolution of drug resistance?
Can we control cancer?
And so many more!
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
American pika
Question
American pika - Ochotona princeps
distribution map
order: Lagomorpha
small, diurnal herbivore
native to cold climates
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
American pika
Question
American pika - Ochotona princeps
talus - rocky slopes
Kalle Parvinen, Anne Seppänen and John Nagy
hay pile for winter
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
American pika
Question
Bodie metapopulation
ore dumps - patches
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
American pika
Question
Question
Dispersal is selected for, because of...
Resource competition
Fluctuating environment
Kin competition
Density dependent dispersal
Large patches: threshold strategy
[Gyllenberg and Metz:2001]
Larger patch models “dilute” the kin benefits
Our question:
How density-dependent dispersal evolves in metapopulation
with small local populations?
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
American pika
Question
Strategy types
Examples of density dependent dispersal strategies
a) threshold for large patch-sizes
b) threshold
emigr.
1
emigr.
1
0
0
x̃ density
local population
1
c) monotone
2
3
4
5
6
7
8
9
10
7
8
9
10
local population size
d) non-monotone
emigr.
1
emigr.
1
0
0
1
2
3
4
5
6
7
8
local population size
9
10
Kalle Parvinen, Anne Seppänen and John Nagy
1
2
3
4
5
6
local population size
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Strategies
Emigration:
Natal dispersal: probability that an individual born in a patch
with n inhabitants will emigrate immediately after birth
Adult dispersal: rate to emigrate from a patch with n
inhabitants
e = (e1 , e2 , ..., eK )
Natal dispersal: 0 6 ei 6 1
Adult dispersal: ei > 0
Immigration:
Probability to stay in a patch when encountered
m = (m0 , m1 , ..., mK −1 )
0 6 mi 6 1
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Local model
a)
Adult dispersal, local dynamics
Birth or
immigration
Immigration
0
1
Birth or
immigration
Death or
emigration
Death or
emigration
2
Death or
emigration
Death or
emigration
Birth or
immigration
Birth or
immigration
Birth or
immigration
Death or
emigration
Death or
emigration
k
K
Local extinction
b)
Natal dispersal, local dynamics
Immigration or
birth without
emigration
Immigration
0
1
Death
Immigration or
birth without
emigration
Immigration or
birth without
emigration
2
Death
Immigration or
birth without
emigration
Immigration or
birth without
emigration
k
Death
Death
K
Death
Local extinction
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Death
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Metapopulation model
Infinite number of patches
Patches connected via global dispersal
Forward Kolmogorov equations for natal dispersal
d
dt p0
d
dt pn
= −αm0 Dp0 + d1 p1 + µ(1 − p0 ),
= [αmn−1 D + (n − 1)bn−1 (1 − en−1 )]pn−1
−[n(bn (1 − en ) + dn ) + αmn D + µ]pn
+(n + 1)dn+1 pn+1 ,
d
p
=
[αmK −1 D + (K − 1)bK −1 (1 − eK −1 )]pK −1
dt K
−[KdK + µ]pK
PK −1
d
p m
dt D = −αD
PK n=0 n n
+ n=1 nbn en pn + KbK (1 − eK )(1 − η)σpK − νD.
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Assumptions
Assume
Separation of time scales:
fast ecological dynamics
slow evolutionary dynamics
The resident is in its population dynamical attractor
A mutant appears
rare
slightly different phenotype
What happens? Can the mutant invade?
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Evolution
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Evolution
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Evolution
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Evolution
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Evolution
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Evolution
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Fitness
Invasion fitness r
Exponential growth when rare.
If r > 0 then invasion is possible.
[Metz et al., 1992, 1996; Geritz et al., 1997, 1998]
Rmetapop - metapopulation reproduction ratio
Operates on dispersal generations
lnRmetapop and r sign equivalent
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Local model
Metapopulation model
Adaptive dynamics
Example
Adaptive dynamics cont.
Singular strategy
Singular strategies
Fitness gradient equals to 0.
Attracting vs. repelling
Unbeatable vs. beatable
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
Strategy types
Examples of density dependent dispersal strategies
a) threshold for large patch-sizes
b) threshold
emigr.
1
emigr.
1
0
0
x̃ density
local population
1
c) monotone
2
3
4
5
6
7
8
9
10
7
8
9
10
local population size
d) non-monotone
emigr.
1
emigr.
1
0
0
1
2
3
4
5
6
7
8
local population size
9
10
Kalle Parvinen, Anne Seppänen and John Nagy
1
2
3
4
5
6
local population size
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
Density-dependence vs. density-independence
K = 10, k = 7
Natal dispersal
Adult dispersal
10
ESS uniform
TSS dens.dep. e
TSS dens.dep. e,m
8
pop.size
pop.size
10
6
4
2
0
ESS uniform
TSS dens.dep. e
TSS dens.dep. e,m
8
6
4
2
0
0
0.2
0.4
0.6
0.8
1
0
0.2
µ
0.6
0.8
1
µ
1
av.emigr.
1
av.emigr.
0.4
0.8
0.6
0.4
ESS uniform
TSS dens.dep. e
TSS dens.dep. e,m
0.2
0
0.8
0.6
0.4
ESS uniform
TSS dens.dep. e
TSS dens.dep. e,m
0.2
0
0
0.2
0.4
0.6
0.8
1
µ
Kalle Parvinen, Anne Seppänen and John Nagy
0
0.2
0.4
µ
Evolution of dispersal
0.6
0.8
1
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=0
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=1
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=2
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=3
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=4
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=5
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=6
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=7
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=8
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t=9
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 10
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 20
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 30
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 40
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 50
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 100
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 150
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 160
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 170
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 180
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 190
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 200
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 210
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 220
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 230
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 240
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 245
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 250
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 255
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 258
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
A Trait Substitution Sequence
K = 10, k = 7, ν = 0.08, µ = 0.06
t = 260
emigration
1
0
1
2
3
4
5
6
pop.size
Kalle Parvinen, Anne Seppänen and John Nagy
7
8
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
Just an exception?
Attracting vertices of the strategy space
ñ
single-step
multi-step
0
0.2
0.4
µ
0.6
0.8
1
8
c) K = 8 emigration
and immigration
1st step up
10
9
8
7
6
5
4
3
2
1
b) K = 8
emigration only
1st step up
1st step up
a) K = 10
emigration only
ñ
7
single-step
multi-step
6
5
4
3
2
1
0
0.2
0.4
µ
0.6
0.8
8
single-step
multi-step
6
5
4
3
2
1
1
Expected threshold
ñ = k 1 − µb < k
Kalle Parvinen, Anne Seppänen and John Nagy
ñ
7
Evolution of dispersal
0
0.2
0.4
µ
0.6
0.8
1
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
Phase plane plot
a)
b)
µ = 0.048
)
µ = 0.055
d)
µ = 0.058
0.6
0.6
0.6
0.6
0.4
0.4
e6
1
0.8
e6
1
0.8
e6
1
0.8
e6
1
0.8
0.4
0.4
0.2
0.2
0.2
laements
PSfrag
replaements
PSfrag
replaements
PSfrag
replaements
0
0
0
0.2
0.4
0.6
0.8
1
0.2
e5
e)
0.4
0.6
0.8
1
0
0
0.2
e5
f)
µ = 0.070
0.2
0
0
0.4
0.6
0.8
1
0
g)
µ = 0.075
h)
µ = 0.080
0.8
0.8
0.6
0.6
0.6
0.4
0
0.2
0.4
0.6
0.8
1
0
0
e5
0.2
0.4
0.6
0.8
1
e5
1
µ = 0.085
0.2
0
0
0.2
0.4
0.6
0.8
1
e5
e1 = e2 = e3 = e4 = 0
e7 = e8 = e9 = e10 = 1
Kalle Parvinen, Anne Seppänen and John Nagy
0.8
0.4
0.2
0.2
0.2
laements
PSfrag
replaements
PSfrag
replaements
PSfrag
replaements
0
0.6
e6
0.8
0.6
e6
0.8
e6
1
e6
1
0.4
0.4
e5
1
0
0.2
e5
1
0.4
µ = 0.065
Evolution of dispersal
0
0.2
0.4
e5
0.6
0.8
1
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
Strategy Complements?
Emigration and immigration are not always complements
mi 6= 1 − ei
Immigrant does not know his neighbors
Newborn knows his mother is there
K = 10, k = 7, µ = 0.07
1
strategy
strategy
K = 10, k = 7, µ = 0.1
e
mnn
0
0
2
4
6
8
local population size, n
10
Kalle Parvinen, Anne Seppänen and John Nagy
1
e
mnn
0
0
2
4
6
8
local population size, n
Evolution of dispersal
10
Evolution
Our inspiration
Model
Results
Summary
Density-dependence
Natal dispersal
Adult dispersal
Adult dispersal
Non-monotone density dependence?
a) t ∈ [0, 10], µ = 0.25
c) t ∈ [80, 750], µ = 0.25
6
2
emigr.
emigr.
5
1
4
3
2
1
0
0
1
2
3
4
5
6
7
8
local population size, n
9
10
b) t ∈ [10, 80], µ = 0.25
1
2
3
4
5
6
7
8
local population size, n
9
10
d) t ∈ [750, 10000], µ = 0.25
8
3
emigr.
emigr.
7
2
1
6
5
4
3
2
1
0
0
1
2
3
4
5
6
7
8
local population size, n
9
10
Kalle Parvinen, Anne Seppänen and John Nagy
1
2
3
4
5
6
7
8
local population size, n
Evolution of dispersal
9
10
Evolution
Our inspiration
Model
Results
Summary
Take-home messages
Nature is full of exciting questions.
Intuition is not always right.
Complex density dependent dispersal may evolve.
Adult dispersers may benefit more
from conditional dispersal strategies.
Hypothesis: bang-bang type dispersal at Bodie.
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal
Evolution
Our inspiration
Model
Results
Summary
Thank you!
Kalle Parvinen, Anne Seppänen and John Nagy
Evolution of dispersal