One of the most common questions asked about our specimens, from visitors of all ages, is ‘Is it real?’. This seemingly simple question is actually many questions in one and hides a complexity of answers.
In this FAQ mini-series we’ll unpack the ‘Is it real?’ conundrum by looking at different types of natural history specimens in turn. We’ll ask ‘Is it a real animal?’, ‘Is it real biological remains?’, ‘Is it a model?’ and many more reality-check questions.
This time: Skeletons and bones, by Mark Carnall
Them bones, them bones… They are all over the place in most museums of natural history: suspended above you, parading around you, or towering menacingly over you in the case of the attention-grabbing Tyrannosaurus rex. When it comes to skeletons you might think the ‘Is it real?’ question is pretty easy to answer; the bones are there, tangibly real, right?
Bones are only found in fish, amphibians, reptiles, birds, and mammals. Other animals possess hard parts which can confusingly be named using similar language, such as the cuttlebone of cuttlefish, or the ‘skeletons’ of corals. These hard parts may resemble bone but are formed in different ways to true bone like the ones we possess.
Unlike taxidermy, discussed in the previous instalment, on the face of it bones are less easy to manipulate and so less likely to be subjectively represented. But individual bones did not exist individually in life, and articulated skeletons, where bones have been attached together, have been manually reassembled to illustrate the shape of the whole animal. The accuracy of an articulated skeleton can depend on a number of things, including the skill and knowledge of the person doing the assembly, the completeness of the bone material, and even the preparation of the bones themselves.
In life, the skeletons of the bony animals are also supported by hard but spongy cartilage and tendons which are not so easily preserved after death. Yet it is the support of the cartilage and tendons, and the form of the surrounding muscle tissue, which gives an animal its natural appearance.
Some articulated skeletons do not account for this non-bony connective tissue. For example, all of the vertebrae in an articulated backbone may be touching each other, whereas in life there would actually be a disc in between each vertebra. Articulated skeletons are often positioned so that parts of the skeleton can be easily seen and accessed, even if the positioning is not realistic or even physiologically possible.
There are also lots of smaller bones which often aren’t preserved as they are too fragile or don’t attach to other bones in life. Examples include clavicles, or collar bones, penis bones, and the hyoid, a bony structure in the neck that supports the tongue. Some skeletons are composite specimens, so they may be made up of bones from multiple individuals to replace missing or damaged parts. Other parts of skeletons on display in museums may have been reconstructed with plaster or filler.
The way that a specimen is ‘skeletonised’ – the processes used to prepare a skeleton from a carcass – can also have a huge effect on the size and shape of bones, altering the size by up to 10 per cent, which can introduce errors in bone measurement, especially for small-boned bats, rodents, lizards, frogs, and fish.
So while there’s a tendency to assume that skeletons are more ‘real’ than other kinds of preserved specimens, they too have their biases. The next time you look at a skeleton try to imagine what is natural and unnatural about its construction, and ask yourself – is it real?
Next time… Fossils
Last time… Taxidermy