Back on Alpha, all those affected are given a full medical work-up. The results show no after effects from their experience on Retha. Bergman speculates the ravine was the nexus of a time warp. The temporal field present in the mist caused the regression of their bodies (clothes and equipment included) to an earlier stage of evolutionary development; the transformation extended to their minds, giving them a Cro-Magnon level of knowledge and intelligence. Unfortunately, there will be no opportunity for a proper study as the Moon has since moved out of range of the planet.