In a cyclic universe, new matter and energy are created about every trillion years when two sheet-like "branes" collide along an extra dimension of space. Branes are predicted by string theory. ... Once the universe is emptied out, a weak attractive force brings our universe's two branes together in a cosmic collision.
Answer:
What increases the frequency of adaptive mutations? = hitch-hiking.
Explanation:
the mutator allele increases in frequency by hitch-hiking, thus facilitating the appearance of a second adaptive mutation
4444444444444444444444444444444444444444
