To establish this fact, however, took recreating the giant beasts' stomachs in a lab—albeit at a much smaller scale. By combining living bacteria and plant matter known to exist during the time of dinosaurs, the researchers simulated the chemistry in dinosaur guts.
The puzzle was how some sauropod dinosaurs grew to dozens of tons in size. Our modern understanding of biological processes suggest no animal should be able to grow this large. And in the age of dinosaurs, nutrient-rich flowering plants had not evolved into the dominant forms we know today. These massive creatures must have survived on even less nutritious plants.
One of the scientists, Dr. Jürgen Hummel of the University of Bonn, speculates sauropods obtained their massive size through a slow metabolism and an advanced digestive system. "We assume that the herbivorous dinosaurs must have had a kind of fermenter, similar to the rumen in cows today."
Dr. Hummel created an array of artificial stomachs to test the nutritive value of a wide spectrum of plants. Surprisingly, the dinosaur-age plants were more nutritious than expected. One variant of the dinosaur brew proved to be more productive even than some grasses.
More questions remain about sauropod digestion including just how they processed such tough plant matter. Modern animals rarely eat Equisetum, a reed-like plant that tested high on the nutrition scale. Equisetum is so tough it would have quickly ground down the dinosaurs' teeth. The researchers speculate sauropods simply gulped these plants whole, or perhaps swallowed stones to help mash the plants in their stomachs.
Photo Credit: (c) Frank Luerweg, Uni Bonn