• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar

Carnegie Museum of Natural History

One of the Four Carnegie Museums of Pittsburgh

  • Visit
    • Buy Tickets
    • Visitor Information
    • Exhibitions
    • Events
    • Dining at the Museum
    • Celebrate at the Museum
    • Powdermill Nature Reserve
    • Event Venue Rental
  • Learn
    • Field Trips
    • Educator Information
    • Programs at the Museum
    • Bring the Museum to You
    • Guided Programs FAQ
    • Programs Online
    • Climate and Rural Systems Partnership
    • We Are Nature Podcast
  • Research
    • Scientific Sections
    • Science Stories
    • Science Videos
    • Senior Science & Research Staff
    • Museum Library
    • Science Seminars
    • Scientific Publications
    • Specimen and Artifact Identification
  • About
    • Mission & Commitments
    • Directors Team
    • Museum History
  • Tickets
  • Give
  • Shop

The Two-Headed Dinosaur

Apatosaurus is a sauropod, or long-necked plant-eating dinosaur, that lived in western North America during the late Jurassic Period roughly 150 million years ago. In the early 20th century, scientists couldn’t agree on what kind of head Apatosaurus had. No skull had ever been found attached to a neck of this dinosaur. So, when Carnegie Museum of Natural History mounted its most complete Apatosaurus skeleton in 1915, it did so without including a skull.

Apatosaurus louisae (right) as it was originally mounted in 1915, without a skull. At left is the skeleton of its relative Diplodocus carnegii.
Carnegie Museum of Natural History’s skeleton of Apatosaurus louisae (right) as it was originally mounted in 1915, without a skull. At left is the skeleton of its relative Diplodocus carnegii, better known as ‘Dippy.’ Credit: Carnegie Museum of Natural History.

The mount stood headless until 1932, when the museum followed prevailing scientific opinion of the day and placed a blunt-snouted, broad-toothed skull on the Apatosaurus. It remained there for another 47 years.

Apatosaurus and Diplodocus skeletons
Apatosaurus (right) and Diplodocus, ca. 1932, after a skull of the blunt-snouted sauropod Camarasaurus lentus had been mounted on the Apatosaurus skeleton. Credit: Carnegie Museum of Natural History.

In 1978, however, Carnegie Museum of Natural History paleontologist Dave Berman and museum research associate Jack McIntosh reasoned that a very different, more Diplodocus-like skull found with the Apatosaurus skeleton back in 1910 was most probably the correct one. A subsequent discovery of a still-connected Apatosaurus skull and neck proved them correct. In 1979, the museum’s Apatosaurus louisae was finally fitted with its proper skull – more than seven decades after its discovery! It remains that way today, on public exhibit in the museum’s dinosaur gallery, Dinosaurs in Their Time.

Apatosaurus Louise
Apatosaurus as it looks today, displayed with its correct skull, which closely resembles that of its relative, Diplodocus. Credit: Melinda McNaugher, Carnegie Museum of Natural History.

Matt Lamanna is a paleontologist and the principal dinosaur researcher at Carnegie Museum of Natural History in Pittsburgh.  Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

Related Content

Ask a Scientist: What kind of dinosaur was a megaraptorid?

Mesozoic Monthly: Dreadnoughtus

The Strange Saga of Spinosaurus, the Semiaquatic Dinosaurian Superpredator

sidebar

About

  • Mission & Commitments
  • Directors Team
  • Museum History

Get Involved

  • Volunteer
  • Membership
  • Carnegie Discoverers
  • Donate
  • Employment
  • Events

Bring a Group

  • Groups of 10 or More
  • Birthday Parties at the Museum
  • Field Trips

Powdermill

  • Powdermill Nature Reserve
  • Powdermill Field Trips
  • Powdermill Staff
  • Research at Powdermill

More Information

  • Image Permission Requests
  • Science Stories
  • Accessibility
  • Shopping Cart
  • Contact
  • Visitor Policies
One of the Four Carnegie Museums | © Carnegie Institute | Privacy Policy | Terms of Use | Accessibility
Rad works here logo