It cannot get any less obvious.

In many primitive species–regardless of galaxy–the issue of predation dictates that the creatures will evolve to evade detection, simply grow too large to be considered a target or become an apex predator.

Homo sapiens seem to defy this rule: their offspring’s cries resonate for miles around like a beacon to hungry creatures, the female adults even seem to prefer travelling around irritably noisily wearing strange, impractical and health-hazardous footwear called ‘high-heels’. Hardly a wonder why they have to engineer bubble environments.