To Replicate or Not?

Animal skulls become objects of wonder at the Museum. During programs, I watch as the majority of children cautiously rub an index finger along sharp teeth, or gaze like little Hamlets into now empty eye sockets. The most outgoing in the group will animate a skull while vocalizing deep growls or unfamiliar shrieks. But as much as we love learning from skulls, we almost always end up loving these teaching tools to death. 

Recently, we started experimenting with adding replica skulls to our teaching kits. There are a few reasons why we sometimes opt to use replicas rather than real skulls. 

This real bobcat skull is more delicate than it looks. Without our intervention, more teeth will likely
come loose and fall out over time, like the top incisor that is already missing. 

The first parts to go on a mammal skull are typically the teeth. Gums help to hold teeth into their sockets while an animal is alive, but all tissue rots or is removed during the cleaning process. Teeth become too loose to stay in the jaw on their own. While single-rooted teeth fall out more readily, those with multiple roots will often remain in sockets for some time. Eventually, though, they fall out or crack in the middle of a program. 

Other parts of the skull will come apart as bone becomes independent for the first time. For example, the fusion point of the two halves of a mandible, or lower jaw, weakens and the pieces eventually separate. We then fuse the jaw back together by gluing the two halves at the fusion point, and adhere a dowel between both parts to prevent them from flexing. But then it only takes one rowdy child to yank pieces apart again with enough effort. 

To add insult to injury, bones will naturally decompose over time. They may naturally become exposed to bacterial and fungal decomposers, who eat away at the proteins remaining within bone after an animal dies. While the process may take up to thousands of years in the right environment, all skulls eventually break down into "nothing." 

This bobcat skull replica mimics even the most minute details of a real skull,
but it is much more durable when put up against the strength and curiosity of young learners.

Fortunately for our teaching collection, replicas are much more durable than the real deal. All parts are cast as one piece, so educators almost never have to worry about small hands getting ahold of tiny teeth when we aren't looking. And they're often made of plastics, after all, which seem to survive in perpetuity.  Perhaps most importantly, an ample supply of teaching skulls doesn't have to directly rely on the death of an animal.