Episode 13 – The Fossil Preparation Lab

Listen to Episode 13 on PodBean, iTunes, or Stitcher!

In this episode, we report from inside the fossil prep lab itself! Our friends Shawn, Shayleigh, and Davis talked us through the intricate work of Fossil Preparation.

In the News:
How Did Plesiosaurs Swim?
Physics meets paleontology as a researcher explores how the long necks of plesiosaurs might have affected their movement through water. [Report]
A Surprise Mass Extinction!
By compiling data from all over the fossil record, researchers revealed a mass extinction of large marine animals around the start of the Ice Age. [Report]
The Bone-Crushing Croc
Not all the top predators of the Jurassic were dinosaurs. Razanandrongobe was a giant predatory croc that roamed Madagascar. [Report by David]
The Warm Eggs of Dinosaurs
Some dinosaurs are known to have sat upon their nests like modern birds. A new study picks apart the chemistry of the eggs to deduce just how warm they were. [Report]

What is Fossil Prep?

When fossils first come out of the ground, they are rarely pretty. Often broken, crushed, and caked with sediment, most ancient remains need some work before they can be properly studied or displayed. That work is fossil preparation.

The goal of prep work is to restore the fossil to as pristine a condition as possible without damaging or erasing any potentially important bits of anatomy or chemistry in the process.

As we discussed in this episode, there are a few major steps involved. Every fossil site (and lab) is different, so the steps and techniques will differ depending on the situation, but here’s a general overview of what to expect from fossil prep:

Workstation1
Behold the fossil preparator’s workstation! Inside that plaster jacket are bits of a prehistoric peccary, and surrounding it are the various tools and solutions that will be used to restore it. Photo by Shayleigh Maden at the Gray Fossil Site

Identification
Before any work can be done, a preparator needs to know what they’re working with. The prep-plan will change depending on what kind of fossil it is, how it’s preserved, what exactly needs to be done, and what is planned for it. A big smashed-up T. rex femur destined for a museum display will go through a different procedure than a delicate but well-preserved snake vertebra intended for chemical analysis.

Consolidation
Fossils are old, and often very fragile. No matter how well you clean and glue your specimen, it won’t matter much if the bones are ready to crumble to dust! Consolidants are chemical mixtures that seep into the tiny cracks and crevices in fossils and cement them together.

Different labs use different solutions – as our guests discussed in this episode, some of the mixtures they’re using at the Gray lab are made specifically for the bones at this particular site.

The techniques that preparators use to apply these chemicals will also vary quite a bit, from swabbing them on with paintbrushes to injecting them delicately with insulin needles.

Workstation2
This is also a preparator’s workstation! This one is focused on sorting through tiny microfossils like frogs, salamanders, snakes, and more. Photo by Davis Gunnin at the Gray Fossil Site.

Cleaning
At best, your fossil might be coated with some light dust you can brush right off. At worst, it might be caked in rock-hard sediment. All of this masks the important features that researchers need to see. The paleontologist’s fossil-cleaning tool-kit is an eclectic mix of equipment: dental picks, toothbrushes, carpentry tools, micro-jackhammers (really!), and more. Fluids like water and alcohol are also important to break down the dirt.

OLYMPUS DIGITAL CAMERA
Here, David scrapes away at sandstone to expose the bones of a fossil lizard from California. This was not a job for a toothbrush! Photo by Sandy Swift.

Reconstruction
Few creatures make it through the fossilization process unbroken. The goal of piecing a fossil back together is rarely to put the hip bone to the leg bone to the toe bone, but instead to repair the individual bones.

In fact, sometime bones are intentionally not reunited – at the Gray Site, for example, the mastodon’s lower tusks will not be placed back inside the jaw, so that they can be studied separately.

20170615_163352
Slowly but surely, this Gray Site mastodon upper tusk is coming together. Photo by David Moscato

It takes a lot of patience, a steady hand, and a good knowledge of skeletal anatomy to find the right fits. It’s a bit like doing a jigsaw puzzle, except every piece is a different shape and size, some pieces are missing completely, other pieces are highly damaged, and you don’t actually know what it will look like until it’s done. But every piece has a fit – you just need to find it.

And More!
Depending on the lab, work might also include sorting through microfossils, opening up plaster jackets to pull out the fossils inside, labeling and organizing the fossils, and all sorts of other tasks.

20170615_161133
Inside this plaster jacket is a chaotic mess of rock, dirt, and a highly damaged mastodon skull (see the teeth!) – it will be many months before this fossil has gone through all of the prep steps. Photo by David Moscato

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