 The flexibility of "Diplodocus" neck is debated but it should have been able to browse from low levels to about 4 m (13 ft) when on all fours.However, studies have shown that the center of mass of "Diplodocus" was very close to the hip socket; this means that "Diplodocus" could rear up into a bipedal posture with relatively little effort.It also had the advantage of using its large tail as a 'prop' which would allow for a very stable tripodal posture.