dinosaurs was comparable. From the 1960s onwards, a dinosaur renaissance took place, a quick increase in the number of studies and critical ideas, influenced by the discovery of additional fossils of Deinonychus, whose spectacular traits refuted what had become entrenched orthodoxy. In 1970, likewise the description of the furry pterosaur Sordes began what Robert Bakker named a renaissance of pterosaurs. Kevin Padian especially propagated the new views, publishing a series of studies depicting pterosaurs as warm-blooded, active and running animals. This coincided with a revival of the German school through the work of Peter Wellnhofer, who in 1970s laid the foundations of modern pterosaur science. In 1978, he published the first pterosaur textbook, the Handbuch der Paläoherptologie, Teil 19: Pterosauria, and in 1991 the second ever popular science pterosaur book, the Encyclopedia of Pterosaurs. This development accelerated through the exploitation of two new Lagerstätten. During the 1970s, the Early Cretaceous Santana Formation in Brazil began to produce chalk nodules that, though often limited in size and the completeness of the fossils they contained, perfectly preserved three-dimensional pterosaur skeletal parts. German and Dutch institutes bought such nodules from fossil poachers and prepared them in Europe, allowing their scientists to describe many new species and revealing a whole new fauna. Soon, Brazilian researchers, among them Alexander Kellner, intercepted the trade and named even more species. Even more productive was the Early Cretaceous Chinese Jehol Biota of Liaoning that since the 1990s has brought forth hundreds of exquisitely preserved two-dimensional fossils, often showing soft tissue remains. Chinese researchers such as Lü Junchang have again named many new taxa. As discoveries also increased in other parts of the world, a sudden surge in the total of named genera took place. By 2009, when they had increased to about ninety, this growth showed no sign of levelling-off. In 2013, M.P. Witton indicated that the number of discovered pterosaur species had risen to 130. Over ninety percent of known taxa has been named during the "renaissance". Many of these were from groups the existence of which had been unknown. Advances in computing power enabled researchers to determine their complex relationships through the quantitative method of cladistics. New and old fossils yielded much more information when subjected to modern ultraviolet light or roentgen photography, or CAT-scans. Insights from other fields of biology were applied to the data obtained. All this resulted in a substantial progress in pterosaur