On Dinosaur Island you can select what each species eats. A recent article (quoted at length, below) shows why this is necessary to simultaneously maintain numerous species of large herbivores.
A new study by a Canadian Museum of Nature scientist helps answer a long-standing question in palaeontology — how numerous species of large, plant-eating dinosaurs could co-exist successfully over geological time.
Dr. Jordan Mallon, a post-doctoral fellow at the museum, tackled the question by measuring and analyzing characteristics of nearly 100 dinosaur skulls recovered from the Dinosaur Park Formation in Alberta, Canada. The specimens now reside in major fossil collections across the world, including the collections of the Canadian Museum of Nature. The work was undertaken as part of his doctoral thesis at the University of Calgary under the supervision of Dr. Jason Anderson.
Mallon’s results, published in the July 10, 2013 issue of the open-access journal PLOS ONE, indicate that these megaherbivores (all weighing greater than 1,000 kg) had differing skull characteristics that would have allowed them to specialize in eating different types of vegetation. The results support a concept known as niche partitioning, which dates to the 19th-century studies of Charles Darwin and came into its own in the 1950s with the development of the science of ecology.
A link to the article is here: