Cromorant=flightlessbirdDownfeathersfourchamberedheartFlightlessbirdGizzardOrnithologyEmu =flightlessbirdFlightfeathersSmallstiffwingsBodyfeathersbeehummingbirdKeratin=proteinin feathersBackbonePhylum -Chordata8,000speciesDifferentcoloredeggsostrich:largesteggsOil coatingmakeswingswaterproofAirssacs inbonessmallesteggsair sacsandlungsWarm-bloodedClass= AvesCropCromorant=flightlessbirdDownfeathersfourchamberedheartFlightlessbirdGizzardOrnithologyEmu =flightlessbirdFlightfeathersSmallstiffwingsBodyfeathersbeehummingbirdKeratin=proteinin feathersBackbonePhylum -Chordata8,000speciesDifferentcoloredeggsostrich:largesteggsOil coatingmakeswingswaterproofAirssacs inbonessmallesteggsair sacsandlungsWarm-bloodedClass= AvesCrop