Dinosaur intelligence has been a point of contention for paleontologists. Non-avian dinosaurs were once regarded as being unintelligent animals but have largely been appraised more generously since the dinosaur renaissance. This new found optimism for dinosaur intelligence has led to highly exaggerated portrayals in pop-cultural works like Jurassic Park. Paleontologists now regard dinosaurs as being very intelligent for reptiles, but generally not as smart as their avian descendants. Some have speculated that if the Cretaceous–Paleogene extinction event had not occurred, the more intelligent forms of small theropods might have eventually evolved human-like levels of intelligence. Popular misconceptions of dinosaur neurology include the concept of a second brain in the pelvis of stegosaurs