[dwild]

Humans were a 5th dimensional race? That was never the case.

Why would another race give a damn about some primitive lifeforms? Why not? Haven't you heard of Green Peaces?

[undersuit]

Post-humans are conjectured by Cooper to be a 5th dimensional race. (Post-)Humans would be very interested in setting up the events in the past(woah slippery slope) that set the stage for the eventual emergence of post-humans.