▁en dem ism , ▁the ▁e colog ical ▁state ▁of ▁a ▁species ▁being ▁unique ▁to ▁a ▁defined ▁ge ographic ▁location . ▁ ▁Specifically , ▁ne o en demic ▁species ▁are ▁those ▁that ▁have ▁recently ▁ar isen , ▁through ▁diver gence ▁and ▁re product ive ▁isol ation ▁or ▁through ▁hy brid ization ▁and ▁pol yp lo id y ▁in ▁plants . ▁Pale o en dem ism , ▁the ▁other ▁sub - category , ▁refers ▁to ▁species ▁that ▁were ▁formerly ▁w ides p read ▁but ▁are ▁now ▁restricted ▁to ▁a ▁smaller ▁area . ▁ ▁Ex amples ▁ ▁" D ar win ' s ▁fin ches ", ▁residents ▁of ▁the ▁Gal á pag os ▁Islands , ▁have ▁been ▁used ▁since ▁the ▁ 1 9 th ▁century ▁as ▁an ▁example ▁of ▁how ▁the ▁descend ants ▁of ▁one ▁ancest or ▁can ▁evol ve ▁through ▁adapt ive ▁radiation ▁into ▁several ▁species ▁as ▁they ▁adapt ▁to ▁different ▁conditions ▁on ▁various ▁islands . ▁Charles ▁Dar win ▁wrote : ... one ▁might ▁really ▁fancy ▁that ▁from ▁an ▁original ▁pau city ▁of ▁birds ▁in ▁this ▁arch ip el ago , ▁one ▁species ▁had ▁been ▁taken ▁and ▁modified ▁for ▁different ▁ends ." ▁▁ ▁The ▁Gal á pag os ▁arch ip el ago ▁is ▁also ▁the ▁home ▁of ▁pale o en demic ▁species . ▁ ▁See ▁also ▁Spe ci ation ▁ ▁Notes ▁ ▁References ▁▁▁▁▁ ▁Category : End em ism <0x0A> </s> ▁The ▁Sie ge ▁of ▁Rome ▁was ▁fought ▁between ▁supp or ters ▁of ▁the ▁Sue bian ▁war rior ▁Ric imer ▁and ▁the ▁Western ▁Roman