▁of ▁soci eties ▁in ▁Europe , ▁South ▁America , ▁Africa ▁and ▁Asia , ▁co ined ▁the ▁term ▁" pop ulation ▁explos ion , ", ▁and ▁played ▁a ▁major ▁role ▁in ▁the ▁naming ▁and ▁development ▁of ▁the ▁ ▁dem ographic ▁transition ▁model . ▁He ▁was ▁also ▁one ▁of ▁the ▁original ▁sch ol ars ▁in ▁the ▁development ▁of ▁the ▁theory ▁of ▁over urban ization . ▁He ▁is ▁also ▁cred ited ▁with ▁co ining ▁the ▁term ▁" zero ▁population ▁growth " ▁ ▁although ▁ ▁George ▁St ol nitz ▁claimed ▁to ▁have ▁that ▁distinction . ▁ ▁Davis ▁had ▁several ▁children ▁while ▁esp ous ing ▁limitations ▁on ▁child b ear ing ▁world wide . ▁Davis ▁also ▁published ▁an ▁influ ential ▁article ▁with ▁Wil bert ▁E . ▁Moore ▁entitled ▁" Some ▁Princi ples ▁of ▁Str at ification ," ▁which ▁was ▁a ▁very ▁influ ential ▁functional ist ▁account ▁of ▁the ▁reasons ▁for ▁social ▁inequality . ▁Davis ▁and ▁Moore ▁synth es ize ▁Dur k heim ▁and ▁Par s ons ▁to ▁argue ▁for ▁the ▁" function al ▁necessity " ▁of ▁some ▁positions ▁over ▁others : ▁those ▁that ▁are ▁highest ▁paid ▁go ▁to ▁the ▁most ▁deser ving ▁individuals ; ▁at ▁the ▁same ▁time , ▁the ▁differential ▁re wards ▁motiv ates ▁individuals ▁to ▁work ▁to ▁fill ▁positions ▁they ▁might ▁otherwise ▁not . ▁Thus , ▁from ▁this ▁perspective , ▁ill ness ▁is ▁a ▁devi ant ▁state ▁because ▁it ▁means ▁that ▁the ▁individual ▁may ▁not ▁be ▁able ▁to ▁fill ▁their ▁role . ▁Soci olog ists ▁see ▁this ▁article ▁as ▁a ▁parad ig m atic ▁case ▁of