There are 7 families of flightless birds in total. They include the Kiwis, Cassowaries, Rheas, Ostriches, Tinamous, Emus and Penguins. There are also numerous flightless birds within other groups of...
We cannot fly because we as human beings do not have the ability to fly. Also because we don't have wings.we also are not areodynamic.and if we were ment to fly we would have wings or other powers.