  We have analyzed the relations between the mutational pressure, recombination
and selection pressure in the bit-string model with sexual reproduction. For
specific sets of these parameters we have found three phase transitions with
one phase where populations can survive. In this phase, recombination enhances
the survival probability. Even if recombination is associated, to some extent,
with additional mutations it could be advantageous to reproduction, indicating
that the frequencies of recombinations and recombination-associated mutations
can self-organize in Nature. Partitioning the diploid genome into pairs of
chromosomes independently assorted during gamete production enables
recombinations between groups of genes without the risk of mutations and is
also advantageous for the strategy of sexual reproduction.
