USF's Museum Blog

Intern-connectivity: Memoirs of the Eocene — Giant Skulls and Ethafoam at the California Academy of Sciences

by Dakota Harr (MA, 2019)

One of my most exciting projects at the California Academy of Sciences during my Summer 2019 Geology Collections internship was the work I did on a massive skull of the prehistoric mammal, Brontops. Standing at around 8-feet tall and 16-feet long, (roughly the size of an African Elephant today), Brontops was an impressive sight during the late Eocene epoch of North America. With a big stocky body and large y-shaped horn situated right on the end of the nose, superficially Brontops resembled a massive rhinoceros, but is actually more closely related to today’s horses. At 5’3, if I curled up in the fetal position, the skull alone is the size of my whole body. Impossibly large and incredibly handsome, I jumped at the chance to give this guy some much needed love and repair and rehouse him in his own little ethafoam bed.

dakota1The Eocene is certainly one of my favorite epochs, being the time of creatures that look like they have come straight out of some 90’s creature feature horror flick.  I simply can’t get enough of the bizarre-looking life that thundered across the Earth some 37 million years ago. During this time, North America was home to truly bone-chilling creatures, such as Enteledonts, otherwise known as “Hell Pigs” (and for good reason, imagine the love child of a werewolf and warthog roughly the size of a small car and you have a pretty good idea of what was going on during this epoch).



Upper Skull of Brontops. Dakota’s head for scale.

My project was essentially to repair damage done to the zygomatic arch (essentially the cheekbone) of the Brontops skull with the use of reconstructive epoxies and adhesives and then to create a custom foam storage jacket to help reduce the chance of future damage to the delicate bone. When thinking about fossil collections, damage might be one of the last things that comes to mind. After all, how delicate can a big hunk of dinosaur femur be? While for the most part, fossils are pretty sturdy, they do often succumb to damage due to the force of their own weight putting pressure on delicate areas, causing breakage and a loss of valuable anatomical information. Contrary to popular belief, most fossils are not found in one solid piece but usually in hundreds of fragments that then have to be carefully reconstructed with adhesives and epoxy by experts in order to create the full skeletal form of the ancient beasts typically on display in museum exhibits.

dakota2 copy 2In truth, the adhesives are more susceptible to damage than the actual fossil material, especially when under the stress from inappropriate temperatures and/or storage methods that degrade properties of adhesives and distribute the mighty weight of a fossil predominantly on areas made weak due to previous reconstruction efforts or simply natural causes. Therefore, once the zygomatic arch had been reconstructed, my main goal was to create a sturdy foam jacket that would get the Brontops skull off its teeth and fitted into a comfortable structure that took the pressure off all its weakest points. This was a long process, mostly due to the length of time and effort it takes to carve out huge chunks foam into complementary structures. The hours of measuring and cutting away foam was worth it in the end though, as I was able to create something that would better preserve this fascinating specimen to inspire the imaginations and probably a few nightmares of future generations of museum visitors and scientists alike.


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