▁ ▁Pale o - Ind ians ▁origin ated ▁from ▁Central ▁Asia , ▁crossing ▁the ▁Ber ing ia ▁land ▁bridge ▁between ▁eastern ▁Si ber ia ▁and ▁present - day ▁Al aska . ▁Hum ans ▁lived ▁throughout ▁the ▁Amer icas ▁by ▁the ▁end ▁of ▁the ▁last ▁gla cial ▁period , ▁or ▁more ▁specifically ▁what ▁is ▁known ▁as ▁the ▁late ▁gla cial ▁maximum , ▁no ▁earlier ▁than ▁ 2 3 , 0 0 0 ▁years ▁before ▁present . ▁Details ▁of ▁Pale o - Ind ian ▁migration ▁to ▁and ▁throughout ▁the ▁American ▁continent , ▁including ▁the ▁dates ▁and ▁the ▁routes ▁tra ve led , ▁are ▁subject ▁to ▁on going ▁research ▁and ▁discussion . ▁ ▁The ▁routes ▁of ▁migration ▁are ▁also ▁deb ated . ▁The ▁traditional ▁theory ▁is ▁that ▁these ▁early ▁migr ants ▁moved ▁when ▁sea ▁levels ▁were ▁significantly ▁lower ed ▁due ▁to ▁the ▁Qu atern ary ▁gla ci ation , ▁following ▁her ds ▁of ▁now - ext inct ▁ple ist oc ene ▁meg af a una ▁along ▁ice - free ▁cor rid ors ▁that ▁stretch ed ▁between ▁the ▁Laurent ide ▁and ▁Cord iller an ▁ice ▁sheets . ▁Another ▁route ▁proposed ▁is ▁that , ▁either ▁on ▁foot ▁or ▁using ▁primitive ▁boats , ▁they ▁migr ated ▁down ▁the ▁Pacific ▁coast ▁to ▁South ▁America ▁as ▁far ▁as ▁Chile . ▁Any ▁arch ae ological ▁evidence ▁of ▁coast al ▁occupation ▁during ▁the ▁last ▁Ice ▁Age ▁would ▁now ▁have ▁been ▁covered ▁by ▁the ▁sea ▁level ▁rise , ▁up ▁to ▁a ▁hundred ▁metres ▁since ▁then . ▁The ▁recent ▁finding ▁of ▁ind igen ous ▁Austral