▁the ▁sun ▁in ▁Africa . ▁With ▁regard ▁to ▁the ▁hypoth es ized ▁recent ▁African ▁origin ▁of ▁modern ▁humans , ▁the ▁author ▁arg ues ▁that ▁af ro - text ured ▁hair ▁was ▁the ▁original ▁hair ▁texture ▁of ▁all ▁modern ▁humans ▁prior ▁to ▁the ▁" Out - of - A frica " ▁migration ▁that ▁populated ▁the ▁rest ▁of ▁the ▁glo be . ▁ ▁According ▁to ▁Clar ence ▁( 2 0 1 2 ), ▁af ro - text ured ▁hair ▁may ▁have ▁been ▁adapt ive ▁for ▁the ▁earliest ▁modern ▁humans ▁in ▁Africa ▁because ▁the ▁relatively ▁sparse ▁density ▁of ▁such ▁hair , ▁combined ▁with ▁its ▁el astic ▁hel ix ▁shape , ▁results ▁in ▁an ▁air y ▁effect . ▁The ▁resulting ▁increased ▁circul ation ▁of ▁cool ▁air ▁onto ▁the ▁scal p ▁may ▁have ▁thus ▁served ▁to ▁facil itate ▁the ▁body - temper ature - reg ulation ▁system ▁of ▁hom in ids ▁while ▁they ▁lived ▁on ▁the ▁open ▁sav ann ah . ▁Af ro - h air ▁requires ▁more ▁mo ist ure ▁than ▁straight ▁hair ▁and ▁tends ▁to ▁shr ink ▁when ▁dry . ▁Instead ▁of ▁stick ing ▁to ▁the ▁neck ▁and ▁scal p ▁when ▁d amp ▁( as ▁do ▁stra ighter ▁text ures ), ▁unless ▁completely ▁d rench ed ▁it ▁tends ▁to ▁retain ▁its ▁basic ▁spring iness . ▁The ▁trait ▁may ▁have ▁been ▁retained ▁and / or ▁preferred ▁among ▁many ▁an atom ically ▁modern ▁populations ▁in ▁equ atorial ▁areas , ▁such ▁as ▁Pol yn es ians , ▁Mic ron es ians , ▁Mel anes ians , ▁Austral oid s