, ▁the ▁hypothesis ▁of ▁an ▁Indian ▁origin ▁appears ▁a ▁pri ori ▁imp laus ible . ▁The ▁earliest ▁evidence ▁for ▁the ▁late en ▁in ▁Islam ic ▁art ▁adjacent ▁to ▁the ▁Indian ▁Ocean ▁occurs ▁in ▁a ▁ 1 3 th - century ▁Egypt ian ▁artifact ▁which , ▁however , ▁is ▁assumed ▁to ▁show ▁a ▁Mediter rane an ▁vessel . ▁Ex c av ated ▁dep ict ions ▁of ▁Muslim ▁vessels ▁along ▁the ▁Eastern ▁African ▁coast ▁uniformly ▁show ▁square ▁s ails ▁before ▁ 1 5 0 0 . ▁▁▁ ▁After ▁ 1 5 0 0 , ▁the ▁situation ▁in ▁the ▁Indian ▁Ocean ▁dram atically ▁changed , ▁with ▁nearly ▁all ▁vessels ▁now ▁being ▁late en ▁rig ged . ▁As ▁Portuguese ▁h ull ▁design ▁and ▁construction ▁methods ▁are ▁known ▁to ▁have ▁been ▁subsequently ▁adopted ▁by ▁Eastern ▁Muslim ▁ship build ers , ▁it ▁is ▁assumed ▁that ▁this ▁process ▁also ▁included ▁the ▁late en ▁rig ging ▁of ▁the ▁novel ▁car avel . ▁Within ▁four teen ▁years ▁of ▁da ▁G ama ' s ▁arrival , ▁late ens ▁were ▁sp otted ▁by ▁the ▁Portuguese ▁on ▁local ▁vessels . ▁ ▁Independent ▁in vention ▁in ▁South ▁Se as ▁▁ ▁The ▁" V " - sh aped ▁and ▁m ast less ▁late en ▁rig , ▁known ▁as ▁c rab ▁cla w ▁sail , ▁of ▁the ▁se af aring ▁people ▁of ▁O ce ania , ▁which ▁was ▁in ▁use ▁as ▁far ▁east ▁as ▁T ong a ▁and ▁Sam oa ▁at ▁the ▁time ▁of ▁European ▁contact , ▁is ▁generally ▁assumed ▁to ▁be ▁an ▁independent ▁in vention ▁on ▁the