Sauropod necks
It is not clear whether saurpods kept their neck vertical or horizontal. Most sauropods lack high vertebral apophyses at the basis of the neck. This has been interpreted as a hint for weakness, thence sauropods would have kept their necks horizontal. However, for a simple problem of momentum, it is much easier to hold a heavy cylinder vertically than horizontally. In fact, the posture requiring much stronger vertebral apophyses is the horizontal one. However, a sauropod with a vertical neck would have needed a really high blood pressure in order for oxygen to reach its brain. But even with a horzontal neck, the head of a Brachiosaurus is already higher than a giraffe's, which is often considered as a reference animal for maximal possible height... Then anyway sauropods must have had some special blood-pumping adaptations. A completely vertical neck would also probably imply an important break in the continuity of the backbone. But one could wonder what would be the use of such a long neck if sauropods did not use it for browsing on higher trees. |