▁and ▁all ▁except ▁Ly all ' s ▁w ren ▁have ▁a ▁prominent ▁super cil ium ▁above ▁the ▁eye . ▁The ▁pl um age ▁of ▁males ▁and ▁females ▁were ▁al ike ▁in ▁Ly all ' s ▁w ren ▁and ▁the ▁bush w ren ; ▁the ▁New ▁Zealand ▁rock ▁w ren ▁shows ▁slight ▁sexual ▁dim orphism ▁in ▁its ▁pl um age ▁and ▁differences ▁between ▁the ▁pl um age ▁of ▁rif le men ▁are ▁pron ounced , ▁with ▁the ▁male ▁having ▁bright ▁green ▁upper parts ▁and ▁the ▁female ▁being ▁d ull er ▁and ▁brow ner . ▁ ▁Both ▁the ▁New ▁Zealand ▁rock ▁w ren ▁and ▁the ▁rif le man ▁also ▁show ▁sexual ▁dim orphism ▁in ▁size ; ▁unus ually ▁for ▁passer ines , ▁the ▁female ▁is ▁larger ▁than ▁the ▁male . ▁The ▁female ▁rif le man ▁also ▁exhib its ▁other ▁differences ▁from ▁the ▁male , ▁having ▁a ▁slightly ▁more ▁u pt urn ed ▁bill ▁than ▁the ▁male ▁and ▁a ▁larger ▁h ind ▁cla w . ▁ ▁The ▁New ▁Zealand ▁wr ens ▁evol ved ▁in ▁the ▁absence ▁of ▁m amm als ▁for ▁many ▁millions ▁of ▁years ▁and ▁the ▁family ▁was ▁losing ▁the ▁ability ▁to ▁fly . ▁Three ▁species ▁are ▁thought ▁to ▁have ▁lost ▁the ▁power ▁of ▁flight : ▁the ▁st out - leg ged ▁w ren , ▁the ▁long - bil led ▁w ren ▁and ▁Ly all ' s ▁w ren . ▁The ▁ske let ons ▁of ▁these ▁species ▁have ▁mass ively ▁reduced ▁ke els ▁in ▁the ▁stern um ▁and ▁the ▁flight ▁fe athers ▁of ▁Ly all