Fossilized dung found with late Cretaceous titanosaurids suggests a broad, unselective plant diet. Besides the plant remains that might have been expected, such as cycads and conifers, there were an unexpectedly wide range of monocotyledons, including palms and grasses (Poaceae), including ancestors of rice and bamboo. This has given rise to speculation that herbivorous dinosaurs and grasses co-evolved.