Taking this to a greater extreme, the terror birds (and their relatives the bathornithids), eogruids, geranoidids, gastornithiforms, and dromornithids (all extinct) all evolved similar body shapes – long legs, long necks and big heads – but none of them were closely related. Furthermore, they also share traits of being giant, flightless birds with vestigial wings, long legs, and long necks with some of the ratites, although they are not related.[4][5]