week 8- adaptive dynamics Flashcards
(14 cards)
what are the two roles in hermit crab contests
attackers: perform shell rapping
defenders: remain withdrawn
how do oxygen conditions affect hermit crab contest
in oxygen starved conditions time in between shell-rapping bouts increases
number of shell-rapping bouts until defenders are evicted by attackers does not depend on oxygen conditions
use Stuart fox tree to discuss what game theoretical model best describes hermit crab contests
hermit crab are attackers or defenders
no behavioural matching so contests best described as SAM or CAM
CAM: defenders compare the vigour of rapping with an absolute threshold rather that with a relative threshold when making their decision
what is adaptive dynamics
studies the long-term evolution of traits in populations assuming that:
1. mutations are infrequenent
2. individuals with the mutant strategy are rare
3. mutant phenotypes are only slightly different from the resident phenotypes
how does adaptive dynamics extend evolutionary game theory and quantitative genetics theory
-evolving traits are continuous (EGT)
-trait dynamics are described (EGT)
-density and frequency dependence is allowed (QGT)
-structured population dynamics are allowed (QGT)
-fitness landscapes are derived (QGT)
-mutational convariences and constraints can be examined (EGT)
-coevolution is integrated (QGT)
-Non-equilibrium population dynamics are allowed (QGT)
what three possibiities do invasion experiments in simple models yeild
- resident wins; mutant dies out
- mutant invades and takes over the population
- coexistence of mutant and resident
what is invasion fitness
initial per capita growth rate of a small variant population within a large resident population at ecological equilibrium
what is a pairwise invisibility plot (PIP)
contour plot of invasion fitness
how do we recognise in a PIP whether a singular point is an ESS
from the vertical line through the singular point
must lie in negative areas only
how do we recognise in a PIP whether a singular point can be reached
from the positive and negative areas
positive immediately left above and right below the diagonal
how do we recognise in a PIP whether an ESS can always invade
from the horizontal line through the singularity
must lie in a positive area only
how do we recognise in a PIP whether two stratergies can coexist
from antidiagonal
must lie in a positive area only
how do we recognise in a PIP whether two stratergies can coexist
coexistence stability:
Seeing this requires a trick: mirroring the PIP in a diagonal then overlay the two PIPs
if the antidiagonal is in positive area only: stable coexistence
what are typical PIPs
attractor: stable equilibrium dot in the middle
repellor: unstable equilibirum dots in corners
