Eternal Recurrence and Evolution

Nietzsche's concept of Eternal Recurrence, taken literally, consists in a closed, exhaustive, repetition of the same sequence, and, so, seems to entail the denial of both a progression from Human to Super-Human, and Evolution, in general.  Nevertheless, the concept of Recurrence cannot completely eliminate the possibility of a progression.  For, even if the same sequence repeats, e. g. the seasons, two cycles are differentiated by their order, i. e. one comes after the other, but not vice versa.  So, Eternal Recurrence constitutes a spiral, not a circle, and, hence, entails the possibility of a progression from one cycle to the next.  Regardless, as has been previously discussed, it seems more likely that he conceives it as a heuristic device that transforms the Past from a burden into a resource for Future creativity, i. e. the origination of a superior species, perhaps via miscegenation and/or eugenics, as he suggests in some places.