Loop-by-loop fibrations are particularly enticing since they allow us to recycle the lower loop differential equations and integral bases. While previous loop-by-loop attempts have had some success [66, 96– 98]
Here m_1\ge 0 and m_2\ge 0 are the mutation rates to and from the beneficial allele, s\ge 0 denotes the strength of the selective advantage of the beneficial allele, \nu \ge 0 governs the variance of the reproductive mechanism and W=(W(t,x))_{t \ge 0, x \in \mathbb {R}}...