In the public sphere, the more ‘flashy’ parts of palaeontology tend to get all the press – excavating fossils in exotic locations and publishing new scientific discoveries. But equally important is how the fossils are cared for, so they are available for research and display, both now and long into the future. One of Te Papa’s most important mandates is preserving New Zealand’s taonga for generations to come. A key role of palaeontology staff is to provide access, expertise and support to anyone visiting our fossil collections – be they iwi, researchers, students, fossil collectors, artists, or other museum professionals. The third in a series of palaeo blogs, William Parker, Hazel Richards, Alan Tennyson, and Felix Marx from the Natural History team describe collection and care processes at Te Papa.
Making a list, checking it twice
It might surprise you to know that less than 0.01% of Te Papa’s fossil collection is actually on display. We have nearly 60,000 catalogued specimens (comprising over a million bones) stored back of house – from tiny shark teeth to moa bones and skulls of ancient whales. Context is everything for fossils, so every single specimen needs to be associated with its key information. What kind of animal is it? When was it found? By whom? Where? Which rock layer was it in? Were there other fossils found with it? How was it prepared? The list goes on.
We keep track of all this information by giving each specimen a unique registration number that is physically written onto it. That number is then associated with its digital catalogue record in our database, where we maintain loads of other data about that fossil, like tracking its physical location in our collection stores, photographs or scans of the specimen, its history of going on loan or display, and any changes in its condition over time.
Consolidation is key
After millions of years in the ground, fossils are often incredibly fragile and prone to crumbling, fracturing or splintering. To handle these taonga safely, we reinforce and protect them using special museum-grade substances known as consolidants. Commonly, we use a polymer resin called Paraloid B-72, which comes as a jar of transparent beads that are then dissolved in acetone to various concentrations.
A friable and fragile specimen might need to be stabilised with a runny, low-concentration consolidant capable of seeping below the outer surface. Eventually, the acetone evaporates, and the resin it carried hardens to strengthen the specimen. Need a thick glue to stick a broken bone back together? Use a gooier 50% solution. Want to undo a previous join? Just use acetone to dissolve the resin and reverse the adhesion process.
Next time you see a fossil on display, look carefully at its surface – if there’s a sheen, it’s probably been coated with a consolidant.
Home – safe and sound
After consolidation and cataloguing, each fossil needs a place within the collection. Smaller fossils tend to be stored in vials or boxes made from archival cardboard, which is chemically inert and free from acids that could harm specimens over long periods of time. Larger fossils are housed within purpose-built foam stillages, which protect them from vibration. Each fossil then goes into a drawer, cabinet or compactus (large, moveable shelving) in our storerooms. These areas are climate controlled, with tight limits on temperature and humidity. Not too hot, not too cold – just right for fossils.
Being in Wellington poses another challenge for looking after fossils – earthquakes. Our shelves are fitted with barriers and ‘seat belts’ that prevent boxes and specimens from toppling out during a big shake.
We hope you’ve gained some insights into the less ‘exciting’ but absolutely critical parts of doing palaeontology. Keep a lookout for our next instalment, when we’ll focus on one of New Zealand’s most significant fossil sites.
