Science Daily has an article about a peer reviewed paper that shows that Brontosaurus (the ‘thunder lizard’) is distinctly different than Apatosaurus.  The authors, a group of paleontologists from Portugal and the UK, think they have conclusive evidence.

The history of Brontosaurus is complex, and one of the most intriguing stories in science. In the 1870s, the Western United States formed the location for dozens of new finds of fossil species, most notably of dinosaurs. Field crews excavated numerous new skeletons mostly for the famous and influential paleontologists Marsh and Cope. During that period, Marsh’s team discovered two enormous, partial skeletons of long-necked dinosaurs and shipped them to the Yale Peabody Museum in New Haven, where Marsh worked. Marsh described the first of these skeletons as Apatosaurus ajax, the “deceptive lizard” after the Greek hero Ajax. Two years later, he named the second skeleton Brontosaurus excelsus, the “noble thunder lizard.” However, because neither of the skeletons were found with a skull, Marsh reconstructed one for Brontosaurus excelsus. Brontosaurus was a massive animal, like Apatosaurus, and like another long-necked dinosaur from the Western United States, Camarasaurus. Because of this similarity, it seemed logical at the time that Brontosaurus had a similarly stout, box-like skull to that of Camarasaurus. However, this reconstruction was later found to be wrong.

Shortly after Marsh’s death, a team from the Field Museum of Chicago found another skeleton similar to both Apatosaurus ajax and Brontosaurus excelsus. In fact, this skeleton was intermediate in shape in many aspects. Therefore, paleontologists thought that Brontosaurus excelsus was actually so similar to Apatosaurus ajax that it would be more correct to treat them as two different species of the same genus. It was the second extinction of Brontosaurus — a scientific one: from now on, Brontosaurus excelsus became known as Apatosaurus excelsus and the name Brontosaurus was not considered scientifically valid anymore.

The final blow to “Brontosaurus” happened in the 1970s, when researchers showed that Apatosaurus was not closely related to Camarasaurus, but to yet another dinosaur from the same area: Diplodocus. Because Diplodocus had a slender, horse-like skull, Apatosaurus and thus also “Brontosaurus” must have had a skull more similar to Diplodocus instead of to Camarasaurus — and so the popular, but untrue myth about “Brontosaurus” being an Apatosaurus with the wrong head was born.

But now, in a new study published in the peer reviewed open access journal PeerJ and consisting of almost 300 pages of evidence, a team of scientists from Portugal and the UK have shown that Brontosaurus was distinct from Apatosaurus after all — the thunder lizard is back!