ically ▁cert ifiable ▁sites ▁of ▁bur ial ▁during ▁this ▁time ▁were ▁in ▁Illinois ▁and ▁Ohio . ▁These ▁have ▁come ▁to ▁be ▁known ▁as ▁the ▁Hope well ▁tradition . ▁Due ▁to ▁the ▁similarity ▁of ▁earth works ▁and ▁bur ial ▁goods , ▁research ers ▁assume ▁a ▁common ▁body ▁of ▁religious ▁practice ▁and ▁cultural ▁interaction ▁existed ▁throughout ▁the ▁entire ▁region ▁( re ferred ▁to ▁as ▁the ▁" H ope w elli an ▁Inter action ▁S phere "). ▁Such ▁similar ities ▁could ▁also ▁be ▁the ▁result ▁of ▁reci pro cal ▁trade , ▁oblig ations , ▁or ▁both ▁between ▁local ▁cl ans ▁that ▁controlled ▁specific ▁territ ories . ▁Access ▁to ▁food ▁or ▁resources ▁outside ▁a ▁cl an ' s ▁territory ▁would ▁be ▁made ▁possible ▁through ▁formal ▁agre ements ▁with ▁neighb ors . ▁Cl an ▁heads ▁would ▁then ▁be ▁buried ▁along ▁with ▁goods ▁received ▁from ▁their ▁trad ing ▁partners ▁to ▁symbol ize ▁the ▁relationships ▁they ▁had ▁established . ▁Under ▁this ▁scenario , ▁permanent ▁settlement s ▁would ▁be ▁likely ▁to ▁develop , ▁leading ▁to ▁increased ▁agricult ural ▁production ▁and ▁a ▁population ▁increase . ▁ ▁Cer am ics ▁during ▁this ▁time ▁were ▁th inner ▁and ▁better ▁quality ▁than ▁earlier ▁times . ▁Ex amples ▁also ▁show ▁pot tery ▁also ▁was ▁more ▁decor ated ▁than ▁Early ▁Wood land . ▁One ▁style ▁was ▁the ▁T rem pe ale au ▁phase ▁which ▁could ▁have ▁been ▁seen ▁by ▁the ▁Hope well ▁in ▁Indiana . ▁This ▁type ▁included ▁a ▁round ▁body , ▁and ▁lines ▁of ▁decor ation ▁with ▁cross - etch ing ▁on ▁rim . ▁The ▁Hav