at the whole of understanding about the family. It was designed as a definitive work, covering all aspects of their biology and evolution, and as part of it every known species was re-evaluated and many of them redescribed. They agreed with prior authors on the semi-aquatic nature of hadrosaurs, but re-evaluated Cope's idea of weak jaws and found quite the opposite. The teeth were rooted in strong batteries and would be continuously replaced to prevent them getting worn down. Such a system seemed incredibly overbuilt for the job of eating soft Mesozoic plants, and this fact confused the authors. Though they stil proposed a diet of water plants, they considered it likely this would be supplemented by occasional forrays into browsing on land plants. Twenty years later, in 1964, another very important work would be published, this time by John H. Ostrom. It challenged the idea that hadrosaurs were semi-aquatic animals, which had been held since the work of Leidy back in the 1850s. This new approach was backed using evidence of the environment and climate they lived in, co-existing flora and fauna, physical anatomy, and preserved stomach context from mummies. Based on evaluation of all this data, Ostrom found the idea that hadrosaurs were adapted for aquatic life incredibly lacking, and instead proposed they were capable terrestrial animals that browsed on plants such as conifers. He remained uncertain, however, as to the purpose of the paddle-like hand Osborn had described, as well as their long and somewhat paddle-like tails. Thus he agreed with the idea that hadrosaurs would have taken refuge from predators in water. Numerous important studies would follow this; Ostrom's student Peter Dodson published a paper about lambeosaur skull anatomy that made enormous changes to hadrosaur taxonomy in 1975, and Michael K. Brett-Surman conducted a full revision of the group as part of his Graduate studies through the 1970s and 1980s. John R. Horner would also begin to leave his impact on the field, including with the naming of Maiasaura in 1979. Hadrosaur research experienced a surge in the decade of the 2000s, similar to the research of other dinosaurs. In response to this, the Royal Ontario Museum and the Royal Tyrrell Museum collaborated to arrange the International Hadrosaur Symposium, a professional meeting about ongoing hadrosaur research that was held at the latter institution on September 22 and 23 in 2011. Over fifty presentations were made at