The Fernbank Museum of Natural History opened in 1992 and is Atlanta’s biggest natural history museum. I work as a volunteer facilitator for the Walk through Time in Georgia exhibit, which is a permanent exhibit that aims to teach visitors about earth history through the Georgia rock record.
My favorite dinosaur display at the Fernbank museum is the Dinosaur Plaza. Situated directly in front of the museum, the Plaza features a family of bronze hadrosaurs — Lophorthon atopus — posed in the middle of a large oval reflecting pool, surrounded by lush gardens of native flowers, trees, and shrubbery.
The Dinosaur Plaza is new — it opened in 2009 — and in the wake of its opening, museum visitors voted on the names of the new dinosaur family. The mother hadrosaur was named Georgia, and her two juveniles were named Haddie and Ferny.
Lophorthon atopus was a small, potentially saurolophine hadrosaur; it did not have a hollow cranial crest like Parasaurolophus. Lophorthon atopus was found in the Selma Group of the Mooreville Chalk Formation and lived in the Early Campanian, so around 84 to 71 mya. No dinosaurs have been found in Georgia yet, but it is plausible that Lophorthon lived in Georgia because it was found nearby. Lophorthon atopus is poorly known dinosaur with only one known occurrence, although other indeterminate Hadrosauridae fossils have been found in the Selma Formation and nearby Blufftown Formation.
One of the things I love most about the Dinosaur Plaza is that Lophorthon atopus is an Appalachian dinosaur. Fernbank is a major cultural attraction and Atlanta icon, and so I think it’s important that the museum celebrate the natural history that is close to home.
The Giants of the Mesozoic exhibit is set up in the Great Hall. It’s really beautiful; the Hall is made of fossil-laden Solnhofen limestone and the high domed ceiling is completely made of windows, so the dinosaurs are lit by sunlight.
The exhibit features full scale fossil replicas of the giant Appalachian theropod Giganotosaurus and mega sauropod Argentinosaurus. The exhibit is meant to communicate not only how the dinosaurs themselves looked, but also how they interacted with each other and the environment around them. The Giganotosaurus is hunting the Argentinosaurus on mounts detailed with a fallen Auracaria tree and fossilized crocidilian, while cast replicas of 24 pterosaurs (21 Pterodaustro and 3 Anhanguera) are strung up above.
Giants of the Mesozoic has its name because it displays some of the largest known dinosaurs. The museum teaches that Argentinosaurus is the biggest dinosaur to ever walk the earth, but when Maximo moved into the Field Museum in Chicago, I assumed that Patagotitan had won that title. However, it seems difficult to truly say whether the Patagotitan at the Field would have been definitively larger than the Argentinosaurus displayed at Fernbank.
The genus Argentinosaurus has only one species, Argentinosaurus huinculensis. The type specimen is MCF PVPH-1, which consists of three anterior and three posterior dorsal vertebrae, a part of a rib, and a left fibula. I found that the holotype’s maximum dorsal centrum diameter, i.e., the diameter of the spine that was involved in carrying the heaviest part of the dinosaur, is 60 cm (Bonaparte and Coria 1993). This measurement of Patagotitan mayorum’s holotype, MPEF-PV 3400/5, is 59 cm in diameter (Carballido et al. 2017). The femur of Argentinosaurus is also larger than that of Patagotitan; the largest reported Patagotitan femur is 2.38 m long and has circumference of 101 cm (as reported in the Electronic Supplementary Materials to Carballido et al 2017) while the circumference of an incomplete Argentinosaurus femur is 118 cm and estimated to be 2.5 m long when complete (Mazzetta et al. 2004), and the circumference of a smaller complete femur is 111.4 cm (Benson et al. 2014).
So while Carballido et al (2017) estimated that Patagotitan was ultimately more massive than Argentinosaurus due to a taller neural spine (the top part of the vertebra that sticks out a bit), measurements of body parts that have to do with supporting mass (weight bearing parts of the anterior dorsal vertebrate and femora) are still larger in the Argentinosaurus. It seems to me that Argentinosaurus might have been ultimately bigger, but it’s hard to know for sure. As Garret always says, we need more fossils!
