Why did people think Stegosaurus had two brains?

August 2, 2012. Contrary to a popular myth, Stegosaurus did not a have a butt brain. Photo by the author at the Utah Field House of Natural History in Vernal, Utah. There's no ... Even if we assume that the expansion in dinosaurs was a glycogen body, we don't yet know what biological role the feature played. read more

As noted here, the stegosaurus had a brain no bigger than a lime, although this is bigger than people initially thought, since it used to be believed that the stegosaurus’ brain was no bigger than a walnut, it still means that the dinosaur had statistically, the smallest brain of any dinosaur we’re currently aware of. read more

One of the many dinosaur myths I wrote about the other day on my blog is that stegosaurus had two brains. Having a brain about the size of a lime, stegosaurus probably wasn’t the brightest bulb on the Christmas tree, and popular culture assumed that it would need a second brain to sustain its relatively enormous body. read more

For decades, popular articles and books claimed that the armor-plated Stegosaurus and the biggest of the sauropod dinosaurs had second brains in their rumps. These dinosaurs, it was said, could reason “a posteriori” thanks to the extra mass of tissue. read more