▁use ▁of ▁tools ▁by ▁early ▁humans ▁was ▁partly ▁a ▁process ▁of ▁discovery ▁and ▁of ▁evolution . ▁Early ▁humans ▁evol ved ▁from ▁a ▁species ▁of ▁for aging ▁hom in ids ▁which ▁were ▁already ▁b ip ed al , ▁with ▁a ▁brain ▁mass ▁approximately ▁one ▁third ▁of ▁modern ▁humans . ▁Tool ▁use ▁remained ▁relatively ▁un changed ▁for ▁most ▁of ▁early ▁human ▁history . ▁Appro xim ately ▁ 5 0 , 0 0 0 ▁years ▁ago , ▁the ▁use ▁of ▁tools ▁and ▁complex ▁set ▁of ▁behav iors ▁emer ged , ▁believed ▁by ▁many ▁arch ae olog ists ▁to ▁be ▁connected ▁to ▁the ▁emer gence ▁of ▁fully ▁modern ▁language . ▁ ▁Stone ▁tools ▁ ▁H omin ids ▁started ▁using ▁primitive ▁stone ▁tools ▁millions ▁of ▁years ▁ago . ▁The ▁earliest ▁stone ▁tools ▁were ▁little ▁more ▁than ▁a ▁f ract ured ▁rock , ▁but ▁approximately ▁ 7 5 , 0 0 0 ▁years ▁ago , ▁pressure ▁fla king ▁provided ▁a ▁way ▁to ▁make ▁much ▁fin er ▁work . ▁ ▁Fire ▁ ▁The ▁discovery ▁and ▁use ▁of ▁fire , ▁a ▁simple ▁energy ▁source ▁with ▁many ▁prof ound ▁uses , ▁was ▁a ▁turning ▁point ▁in ▁the ▁techn ological ▁evolution ▁of ▁hum ank ind . ▁The ▁exact ▁date ▁of ▁its ▁discovery ▁is ▁not ▁known ; ▁evidence ▁of ▁bur nt ▁animal ▁b ones ▁at ▁the ▁C rad le ▁of ▁Hum ank ind ▁suggests ▁that ▁the ▁domestic ation ▁of ▁fire ▁occurred ▁before ▁ 1 ▁Ma ; ▁scholar ly ▁cons ensus ▁indicates ▁that ▁H omo ▁ere ct us ▁had ▁controlled ▁fire ▁by ▁between ▁ 5