I would assume that if the earth was already in an STS density at this time, it would greatly benefit the 4th D STS control system to 'infuse' certain skills into the indigenous population, in order to propagate its existence. Whether this would mean showing them physically, or just inserting the knowledge into the group consciousness somehow I've no idea. Or maybe they did just get lucky with a lightening strike one day lol.
In terms of the original Homo Sapiens population which first entered the 3rd D STS environment I would be very surprised if the basic 'Earth 101' skills weren't given on entry, as a primer to expanding and becoming a fruitful crop in which to harvest off at the 4th D level. You wouldn't plant essential crops and then neglect to feed them now would you? They die off quicker than they could multiply.
Think of all the other things that we now know, but must of been amazing revelations once first 'discovered/observed' - metal smelting; alcohol fermentation etc.
Food for thought.