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Rebuilding the skull of Emily the badger


This is the fifth post that I have written about my badger skeleton, Emily, who I found as a roadkill near my village. I left to decompose in Mortuary wood, checked her again in August, then finally had to collect her in December after a bad storm blew down the wood where she was hidden, before cleaning her.  This week I am going to talk about the skull and putting it back together again.   

The big surprise when I collected Emily was that although her head looked intact when I found her. Her skull had been massively fractured, as if she was just hit on the chin by a car or lorry when she stepped out to cross the road. When I first found her, I wasn't even sure if I could ever repair her skull, but I've done the best I can, and even though it's not perfect, I'm quite proud of how she looks.

The smashed skull

Here's what I had to work with. There were 29 pieces of bone or teeth (plus another one which I found later), some of which were obvious, and others which I couldn't rebuild, like the nasal turbinates (the thin papery bones inside the nasal cavity). In the end , some bits were still missing, but after checking the remains twice I still couldn't find them.

Glueing the pieces back together is tricky. I used ordinary general  glue from B&Q which dries clear, and wire and blu-tac. Some people use a bowl of rice to rest the skull on after you glue a bit together, my family reads the Guardian so all I had to use was couscous.

Left side and top of skull

The first problem was because badger skulls have the lower jaws permanently attached to the skull with a hinge, which makes them very unusual. Because of this, I decided to glue the skull in two main parts, left and right, so the jaw could be reattached before the two halved were glued together.

The two bits of skull that are circled are the two bits that we glued together first. The bigger piece is the top of the braincase with the sagittal crest (a ridge down the skull which jaw muscles attach to), and the smaller bit was another bit of braincase. I identified it because it was curved, smooth on one side but wrinkly on the other.

This is the wrinkly side, the inside of the braincase. The smaller piece is at the top. Once they are pushed into the couscous (rice or sand works well for Telegraph or Sun readers) you can add the clue along the crack. You can wipe off any excess with baby wipes.

The next two bits were the left side of the skull, and the top of the snout, just in front of the eyes. Both bits were easy to recognise:

When that bit was attached, the braincase and sagittal crest part could be glue on as well. This was now the full left side of the skull, and most of the top.

The next part was to add more pieces onto the braincase on the other side. This piece was the side of the braincase and the right ear.

I used white-tack to help it stay together while the glue set on the inside. The white-tac had to be peeled off really carefully afterwards, though.

This is the inside of the braincase again. The glue was really messy but it didn't matter too much as no-one would see it, and the more glue made it stronger.

Some of the bits we joined together were really small. This tiny triangle went inbetween the braincase part and the ear bone part

This is the back of the skull, where the spine enters the braincase. That piece is called the foramen magnum which is Latin for "hole as big as a  chocolate covered ice lolly". Between that piece and the top of the braincase was a gap where the pieces had been smashed or lost. That meant that piece had to be held in place just by the ear bones on either side. At this stage that part wasn't glued in place.

This is it at the same stage looking down from the front.

This was as much as I could do on the left side and braincase for the moment !

The right side and underneath

The bits I glued next were the roof of the mouth (palate) and the right side of the skull, including the zygomatic arch (the cheekbone which which goes around the upper back part of the jaw). The third smaller bit was the final part of the zygomatic arch, which included the 'hinge' that the lower jaw slots into.

This is what the two bigger bits looked like when they were glued together. I glued in the front incisors at the same time. There are only five so far because the socket for the sixth one, on the right, was broken in half between the two pieces.

Again I used cous-cous to let the three pieces to set. You can see the third piece at the back of the skull. It is starting to look good !

The next part was the right ear bone which fits behind the back of the zygomatic arch. This had to be glued on strongly, because it would hold the foramen magnum piece in place.

Lower jaws

Here I had a problem. When the badger decided to headbutt the car, the point of impact was the front right of the jaw, shattering it into lots of pieces. A badger jaw is one of the strongest bones I know of, but this one was not just strong enough., and the right side (at top) had snapped off. The rough bit on the left side (lower one) is just the join between the two halves of the jaw.

With a LOT of testing I found two very small parts of bone which reconstructed the front lower part of the jaw.

When I put the other side of the jaw against it it looks complete from this angle, doesn't it ? But no, there is a huge chunk missing from below and the two sides only meet for a couple of millimeters overlap, not enough to hold a join.

I didn't know how to join the jaws now until dad suggested I could join them by wires. First of all I drilled a hole in the base of the left side (the small bits glued in front weren't strong enough to drill through).

This is the bit of wire that we were going to use. It would go from the left side, bends round, and back into the left part, joining the two.

This is it from underneath in the left part first. The angle it was bent at was too much at this stage, but you get the idea. The hole it went in on the broken right side is the root canal, which is a small tunnel which goes underneath the teeth.

This is it bent and glued. To keep it in place we put another bit of wire bent with a hook at each end to fit in the other end of the root canal.

To glue it I used the cous-cous and rubber band to keep it in place.

Putting the three parts together

Here are the two halves of the skull I made earlier. The join was good but not perfect. I think the skull must have flexed at the point of impact, so the joins are very difficult to get back perfectly on both sides. Also this was only my first attempt of doing this:

Before the two halves were put together I checked the jaw fitted

This was a first attempt at gluing the two halves, so the crack at the top is bigger than in the final version. If you look carefully, you can see the big bit missing from the jaw, and the wire.

Finding an extra bit

After laying out the skeleton I realised that the tail bones were missing, so I sent Dad went back out to the wood to see what he could find. He found the tail (gross story) and this is what he also found doing a fingertip search !

It was the missing bit of the jaw !

I took apart the jaw, and it fitted perfectly ! I glued it here, then rewired. The wire was still needed because there was a bit in front which was still missing.

The final result

  It took me about a week to go from this to this:

This is the left side:

This is from the back:

The teeth and jaws, with the gap at the point of impact:

And this is all the pieces that were needed to reconstruct the jaw:

This is the right side:

And from above:

This was the jigsaw puzzle of a braincase:

I'd LOVE to have found all the missing pieces, but with the body not being fully decomposed, they must have got lost in the fur, and after looking twice with rubber gloves on, I don't think I'll ever find them now. But this is till one of my favourite skulls now because it was put back together from scratch !

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matt said...

The skull is broken because the animal looks at the car before it gets hit so the skulls of most road kill are broken like that, But you did a good job fixing it!

Ric said...

Astonishing achievement, well done Jake (and Nick!)

neil said...

looking forward to get your book next month jake

Psydrache said...

Oh, I love such puzzles like this and you did a good job on it. It's a good idea to use white-tac stuff and what a clever idea with the wire.

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