Brontosaurus Returns!! Separation from Apatosaurus

Brontosaurus and Apatosaurus

The confusion between Brontosaurus and Apatosaurus dates back to 1903.
The Field Museum of Natural History in the United States re-examined the fossils of a dinosaur named Apatosaurus in 1877 and another named Brontosaurus in 1879. In 1903, the research team concluded that "Apatosaurus and Brontosaurus, once thought to be two different genera, are actually the same genus." As a result, Apatosaurus, which was named first, became the valid name, and the name Brontosaurus became invalid.

However, this finding was not widely known to the public, and the name "Brontosaurus" could be seen in general books and encyclopedias until the 1970s. Unsurprisingly, the name Brontosaurus has disappeared from recent encyclopedias.

The Return of the Genus Brontosaurus

On April 7, 2015, the Universidade NOVA de Lisboa in Portugal published a paper on "the evolution of the Diplodocidae family" in the online academic journal PeerJ.
According to the paper, titled "A specimen-level phylogenetic analysis and taxonomic revision of Diplodocidae (Dinosauria, Sauropoda)," "enough differences were found between the fossils once discovered as Brontosaurus and Apatosaurus to constitute separate genera." The skeleton of Brontosaurus is said to be more slender than that of Apatosaurus, with one end of the scapula being roundly expanded and the ankle bones being longer. The paper proposes that Brontosaurus and Apatosaurus should be distinguished.

If the results of this study are accepted, the name "Brontosaurus" may be revived as an official scientific name (genus name) after about 110 years.

*** Update ***
As of 2018, the majority view denies the independence of Brontosaurus.
It was pointed out that what was considered Brontosaurus was "the body of an Apatosaurus with the head of a Camarasaurus," and the name became invalid once again.