Ok, so my idea is for an anomalous phenomenon where a small population of a species will rapidly evolve and develop new traits unusual for the clade the species are in. E.G. flippers in predatory cats, extremely long legs in goldfish, etc. The traits always somehow solve an evolutionary challenge within the species, but the rapid evolution usually means they split off from the original species enough too be considered a separate species.
Now, the directed aspect comes from when a small tribe of humans previously not known in Antarctica was discovered. These people claimed that an entity would appear in their dreams, and afterwards the next few children born would have new evolutionary traits E.G. shorter stature, increased amount of hair, decreased metabolism, etc which coincides with sleep disturbances noted in animals being affected by the anomaly.
Thoughts?