unn atural ) ▁grouping ▁since ▁they ▁found ▁different ▁species ▁to ▁group ▁among ▁the ▁sub species . ▁ ▁The ▁orn ith olog ists ▁Hein ▁van ▁Gr ouw ▁and ▁Julian ▁P . ▁H ume ▁concluded ▁in ▁ 2 0 1 6 ▁that ▁many ▁of ▁the ▁old ▁accounts ▁had ▁errors ▁in ▁the ▁bird ' s ▁proven ance , ▁that ▁it ▁was ▁en demic ▁to ▁Lord ▁How e ▁Island , ▁and ▁suggested ▁when ▁the ▁spec im ens ▁were ▁collected ▁( between ▁March ▁and ▁May ▁ 1 7 8 8 ) ▁and ▁under ▁which ▁circumstances ▁they ▁arrived ▁in ▁England . ▁They ▁concluded ▁that ▁the ▁Lord ▁How e ▁sw am phen ▁was ▁a ▁valid ▁species ▁which ▁changed ▁colour ation ▁with ▁age , ▁after ▁re construct ing ▁the ▁colour ation ▁of ▁ju ven ile ▁birds ▁before ▁turning ▁white ▁( which ▁was ▁distinct ▁from ▁other ▁sw am ph ens ). ▁Van ▁Gr ouw ▁and ▁H ume ▁found ▁the ▁Lord ▁How e ▁sw am phen ▁an atom ically ▁more ▁similar ▁to ▁the ▁Austral as ian ▁sw am phen ▁than ▁the ▁Philipp ine ▁sw am phen , ▁and ▁suggested ▁that ▁studies ▁with ▁more - complete ▁data ▁sets ▁than ▁the ▁earlier ▁DNA ▁might ▁yield ▁different ▁results . ▁Due ▁to ▁their ▁an atom ical ▁similar ities , ▁ge ographic ▁proxim ity ▁and ▁the ▁re colon isation ▁of ▁Lord ▁How e ▁and ▁Nor folk ▁Island ▁by ▁Austral as ian ▁sw am ph ens , ▁they ▁found ▁it ▁likely ▁that ▁the ▁Lord ▁How e ▁sw am phen ▁was ▁desc ended ▁from ▁Austral as ian ▁sw am ph