Radius (bone) ulna (center of the circle) to the edge of the radius (the circle). The ulna acts as the center point to the circle because when the arm is rotated the ulna does not move. In four-legged animals, the radius is the main load-bearing bone of the lower forelimb. Its structure is similar in most terrestrial tetrapods, but it may be fused with the ulna in some mammals (such as horses) and reduced or modified in animals with flippers or vestigial forelimbs. Radius (bone) The radius or radial bone is one of the two large bones of the forearm, the other
Dreadnoughtus parts of the skeleton suggest that the only known individual of "Dreadnoughtus schrani" was approximately long and stood about 2 stories tall. At 1.74 m, its scapula is longer than any other known titanosaur shoulder blade. Its ilium, the top bone of the pelvis, is also larger than any other, measuring 1.31 m in length. The forearm is longer than any previously known from a titanosaur, and it is only shorter than the long forearms of brachiosaurids, which had a more inclined body posture. Only "Paralititan" preserves a longer humerus (upper arm bone). Although each species likely had slightly different