Proximal Pronunciation

Fun Facts

• ✓The proximal head of the femur in T. rex sits almost directly beneath the hip socket, proving it walked with an upright, bird-like posture rather than a sprawling lizard stance, a conclusion scientists confirmed by measuring joint angles in the 1970s.
• ✓In sauropods like Brachiosaurus, the proximal humerus is so massive it measures over 1.8 meters in circumference in large specimens, giving the upper arm more surface area for muscle attachment than almost any other land animal ever discovered.
• ✓Forensic paleontologists use the proximal growth plates of dinosaur bones to estimate age at death, because unfused plates indicate a juvenile, a technique first systematically applied to dinosaur bones by Jack Horner and colleagues in the 1980s.
• ✓The proximal tail vertebrae of Ankylosaurs are fused into a rigid handle called the handle region, which transferred the enormous force of a tail-club swing directly into the body without snapping the spine.
• ✓In birds, which are living dinosaurs, the proximal end of the ulna is covered in small bumps called quill knobs, and scientists found identical knobs on the proximal ulna of Velociraptor mongoliensis in 2007, proving it had feathers even though none were preserved.