The evolution of synergism
Dr. Daniel Falush (Dept. Biology, Facul. Science, Kyushu Univ.)
5月12 日 （火） 午後１時３０分より
九大理学部３号館 ６階 ３６３１
数理生物学セミナー室
The mutational load of an asexual population is 1-exp(U)
, where
U is the total deleterious mutation rate per generation. In a sexual
population, the load may be substantially less than 1-exp(U)
, provided
that there are synergistic fitness interactions between mutations.
As a
result, synergistic interactions would make it possible for
sexual species
to survive a mutation rate of greater than one. Recent measurements
of
fitness interactions in the bacteria E. coli and the filamentous
fungus A.
niger found no synergism on average. I show that synergism is likely
to
evolve in response to a high mutation rate, but only if species
are
sexual. I argue that significant synergism may be restricted
to obligately
sexual species with a high mutation rate.