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The Q? Blog

Giving Fossils a Facelift

by Devin Reese -- Feb 14, 2017

Devin is the lead digital science writer for the Q?rius website. She writes and gathers media for the Smithsonian Science How? webcast series,...

A broken, fossil tyrannosaurid dinosaur tooth found on the ground in the Judith River Formation in Montana. Smithsonian photo by Michelle Pinsdorf.
A broken, fossil tyrannosaurid dinosaur tooth found on the ground in the Judith River Formation in Montana. Smithsonian photo by Michelle Pinsdorf.

A fossil, if you think about it, has not shown its best face in a long time, maybe never. It has spent millions of years embedded in rock, ice, tar, or amber. It is a fossil preparator’s job to remove a fossil from the surrounding materials to reveal it for study and display. The difficulty of the preparation depends not only on what the fossilized organism is, but also how it has changed over time.

We think of fossils as animals or plants that have mineralized (changed to rock). But, that is only part of the story. Fossils are defined as any traces of life 10,000 years old or older. A fossil can be as subtle as a footprint or as substantial as a skeleton. Whether it mineralizes or not depends on the conditions it experiences and for how long. Living material buried in ocean sediment might get totally replaced with minerals, while living material in a peat bog might survive for thousands of years nearly unchanged. 

A fossil preparator’s work often begins in the field, with the extraction of a fossil from the landscape where it is discovered. Along with the fossil comes a lump of surrounding material, which is left on as protection for packaging and transport to a fossil preparation lab. There, a fossil preparator uses an array of specialized tools to remove the material around the fossil. Depending on the matrix, tools may range from soft brushes to metal dental picks or even air-powered, needle-tipped jackhammers. 

But not all fossil organisms are created equal. Usually the hard parts of an organism, such as bones, shells, or stems, have fossilized. The soft parts decay or are eaten away. A fossil preparator must piece together fossilized bits of the organism like a puzzle, restoring missing parts using information from other sources about what they should look like. This makes a preparator part scientist, part detective, part artist, and part engineer.

Preparator Michelle Pinsdorf prepares fossils for display and research at the Smithsonian’s National Museum of Natural History. Learn more about her job, and how volunteers play a role, in the "Smithsonian Science How" webcast on Thursday, March 9, 2017. During Inside the Smithsonian’s Fossil Prep Lab (airs at 11 a.m. and 2 p.m. EST on the Q?rius website), Michelle will take you on a tour of the Fossil Prep Lab while answering your questions live. You can also get teaching resources to use with the webcast.