english: So that when there was a sudden accidental discovery by one member of the group, say the use of fire, or a particular type of tool, instead of dying out, this spread rapidly, horizontally across the population, or was transmitted vertically, down the generations.
non_english: Tako da kada se dogodilo iznenadno slučajno otkriće od strane jednog člana grupe, recimo upotreba vatre, ili određenog tipa oruđa, umesto da nestane ono se brzo širilo, horizontalnim putem kroz populaciju ili se prenosilo vertikalno, kroz generacije.