yan ▁R ift ▁Valley , ▁where ▁the ▁oldest ▁known ▁stone ▁tools ▁were ▁found . ▁Stone ▁tools ▁recently ▁discovered ▁at ▁the ▁Shang chen ▁site ▁in ▁China ▁and ▁dated ▁to ▁ 2 . 1 2   mill ion ▁years ▁ago ▁are ▁claimed ▁to ▁be ▁the ▁earliest ▁known ▁evidence ▁of ▁hom in ins ▁outside ▁Africa , ▁sur pass ing ▁D man isi ▁in ▁Georgia ▁by ▁ 3 0 0 , 0 0 0 ▁years . ▁ ▁H omo ▁ere ct us ▁ ▁Between ▁ 3 ▁and ▁ 2   mill ion ▁years ▁ago , ▁H omo ▁spread ▁throughout ▁East ▁Africa ▁and ▁to ▁Southern ▁Africa ▁( T el anth rop us ▁cap ensis ), ▁but ▁not ▁yet ▁to ▁West ▁Africa . ▁Ar ound ▁ 1 . 9   mill ion ▁years ▁ago , ▁H omo ▁ere ct us ▁migr ated ▁out ▁of ▁Africa ▁via ▁the ▁Lev antine ▁cor rid or ▁and ▁Horn ▁of ▁Africa ▁to ▁E uras ia . ▁This ▁migration ▁has ▁been ▁proposed ▁as ▁being ▁related ▁to ▁the ▁operation ▁of ▁the ▁Sah aran ▁p ump , ▁around ▁ 1 . 9   mill ion ▁years ▁ago . ▁H omo ▁ere ct us ▁dispers ed ▁throughout ▁most ▁of ▁the ▁Old ▁World , ▁reaching ▁as ▁far ▁as ▁S out heast ▁Asia . ▁Its ▁distribution ▁is ▁trac ed ▁by ▁the ▁Old owan ▁l ith ic ▁industry , ▁by ▁ 1 . 3   mill ion ▁years ▁ago ▁extending ▁as ▁far ▁north ▁as ▁the ▁ 4 0 th ▁parallel ▁( X ia och ang li ang ). ▁ ▁Key ▁sites