Two sauropods put next to a human for size comparison.
Sauropods were the largest creature to ever roam the earth. The largest of these, the Apatosaurus, was 70 to 90 feet long, 10 to 15 feet high, and weighed between 33 and 38 tons. Sauropods had incredibly large necks but not very large heads, which allowed them to cover lots of ground as they swept the fields looking for things to eat. . One Sauropod, the Mamenchisaurus, had a neck that was about 46 feet in length. Some dinosaurs held their necks in a more vertical position, therefore reaching high up in trees to reach leaves and things, while others held their necks in a more horizontal position to reach food on the ground easier. One theory stated that Sauropods may have had a second brain in the end of their tail, but scientists later discovered that to be a large obtrusion of the spinal cord, which may have controlled movements in the legs and tail. This enlargement was larger than the small brain in the Sauropod, however, which at first confused scientists. These dinosaurs walked on four legs, each foot having five toes. They had very large stomachs to eat all of the food they needed to energize their ginormous bodies. Their teeth were blunt and pencil-shaped. .
Sauropods ate mostly conifers, which dominated plant life when they lived. They also might have eaten foods such as: Ginkos, seed ferns, cycads, bennettitalean ferns, club mosses, and horsetails. There is no way to determine what the exact diet of these dinosaurs was, but they certainly could have had different diets according to the different species. . There are two basic tooth types for Sauropods; a robust tooth form, and a peg-like tooth form. The Diplodicus, which had the peg-like tooth, is thought to have eaten soft and aquatic vegetation, or it softly pulled from terrestrial vegetation. The Camarasaurus, which had the robust tooth form, is thought to have eaten rougher and more firm vegetation. Scientists try to determine a dinosaur's eating patterns by looking at the patterns on the teeth of the dinosaurs, but these are all simply guesses and cannot be proven. Some things can be learned from looking at tooth-marks, but certainly not everything. .
This video shows how a dinosaur could survive with such a large neck and small head.