Speaker
Nadav Shnerb
Description
All environments vary in time, and these fluctuations affect the survival
and reproduction of individuals. Uncorrelated fluctuations among
individuals produce demographic stochasticity (genetic drift). Coherent
fluctuations across entire populations (environmental stochasticity)
produce random fluctuations in allele fitness and in carrying capacity.
In some cases, and in particular under the standard Moran dynamics,
fluctuating fitness acts as a balancing selection mechanism and
stabilizes an attractive coexistence state. Noise induced stabilization
(NIS) of this type affects dramatically the evolutionary dynamics. I will
present a few results that have to do with the evolutionary process in
fluctuating environment, with and without NIS. These include:
1. The chance of ultimate fixation, the time to fixation and the time to
absorption (either fixation or loss) for a two-allele system under drift,
fluctuating selection and fluctuating carrying capacity [1-3].
2. NIS assisted stochastic tunneling [2].
3. Site-frequency spectrum for multi-allele system [4].
4. The speed of evolution under fluctuating selection in the
successional-fixation phase and in the clonal interference phase [5].
5. Inference problems, the effect of environmental stochasticity on
dn/ds ratio, McDonald-Kreitman test, coalescence theory and so on.
[1] Fixation and absorption in a fluctuating environment. M Danino, NM
Shnerb, Journal of theoretical
biology 441, 84-92 (2018).
[2] Noise-induced stabilization and fixation in fluctuating environment,
I Meyer, NM Shnerb, Scientific
reports 8 (1), 9726 (2018).
[3] Stability of two-species communities: drift, environmental
stochasticity, storage effect and selection,
M Danino, DA Kessler, NM Shnerb, Theoretical population biology 119,
57-71 (2018).
[4] Theory of time-averaged neutral dynamics with environmental
stochasticity, M Danino, NM Shnerb,
Physical Review E 97 (4), 042406 (2018)
[5] Environmental stochasticity and the speed of evolution, M Danino,
DA Kessler, NM Shnerb, Journal
of Statistical Physics 172 (1), 126-142 (2018)
Primary author
Nadav Shnerb
