I wanted to do a three-way comparison between my carnivoran skulls, but I’m too impatient to wait till I’ve got the fox’s skull out of its head. So here are the two I have now: the badger (left) and the cat (right):

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(Both skulls appear with their first three cervicals.)

As you can see, the badger is more impressive in every way. It’s physically bigger of course, but also much more robust, as most easily seen in the zygomatic arches and the fully fused skull. Also relevant is the huge sagittal crest, which you will recall anchored hugely oversized jaw-muscles. In comparison, the cat’s jaw muscles were like those of pussy-cats.

It’s like the difference between a tyrannosaur and an allosaur.

You can see the crest more clearly — and general robustitude — in anterodorsolateral view:

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We really do underestimate what awesome animals badgers are. One of the many reasons I would never participate in a badger cull is simple, straightforward fear.

Do not meddle in the affairs of badgers, for they are unsubtle and quick to bite your arm off.

There’s no sense in decapitating a badger if you’re not going to make good use of the severed head. So here’s what I did with mine. First, a reminder of the state it was in after yesterday’s adventures:

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Ideally, I would have liked to skin the head — it would have made subsequent stages easier and less messy. But as I noted last time, badgers have very tough skin, and it was hard to do anything with it. I feared that the force necessary would at best damage the underlying bone, and at worse give me a nasty cut.

So I satisfied myself with trimming away the flesh collar, leaving the head-and-anterior-neck segment a little shorter, and of a suitable size to go into the saucepan:

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See?

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Then it was a simple matter of filling with hot water …

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… then bringing it all up to a simmer, and giving it a couple of hours while I played some Skyrim and watched an episode of Elementary. Once I’d drained the water off, here’s the result of the first simmer:

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As you can see (you may need to click through to make it out properly), that tough skin has contracted so hard that it’s pulled away from the skull at the top, exposing part of the distinctive midline crest.

Anyone, with the skin now softened it was relatively easy (though disgusting) to peel it off. Once all the rest of the superficial soft-tissue was gone, the massive massive muscles that attached to the midline crest were apparent.

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I broke these off:

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You can see one of them in the last photo. It really is a substantial piece of equipment: and you can see as well that the muscle mass going through the zygomatic arches is substantial.

You may also notice that at this stage, I’ve left the nose intact. That’s because I didn’t want to risk damaging the delicate nasal turbinates by pulling the soft-tissue away too roughly. Instead, I left it on for the second simmer:

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As you can see, it came out from that with the meat much more cooked, and so easier to remove:

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In my previous adventures preparing mammal skulls, I’ve found that one of the most satisfying moments is when the mandible (lower jaw) comes away from the cranium. You really feel that you’re making progress then, and it becomes much easier to reach some of the tricker areas of soft-tissue. That doesn’t happen with badgers: they jaws are permanently articulated, with cylindrical articular condyles wrapped in incomplete bone-tunnels. (I hope I can show you this properly one preparation is complete.)

Anyway, I was able to do a much better job of removing the meat this time: only scraps are left, and I was also at this point able to remove and begin cleaning the first few cervical vertebrae. I have the atlas, axis and damaged third. (I discarded the last of these, since it’s not complete.) Here’s the state of it at this point:

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And that skull in right lateral view, hopefully dispelling any remaining misconceptions you may have had about badgers being cute:

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As you can see, there were still plenty of scraps of hard-to-remove flesh clinging on, especially around the jaws and the base of the cranium. So it was time for simmer number three. I will spare you yet more photos of my saucepan, and instead skip straight to the skull as it appeared after this phase, and after I’d remove more of the flesh. Much nicer:

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You may be wondering, what is the best way to clean the teeth of a dead and partially prepared badger skull? Sometimes the obvious answer is the right one, and this is one of those occasions. A toothbrush is the tool of choice, and it works wonders with the base of the cranium, too. (Warning: do not allow the toothbrush to re-enter civilian society after this experience.)

Here we have the skull with the mandible open:

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Do not get bitten by a badger.

Skull in dorsal view:

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(I will prepare nicer, scientific-quality photographs in orthogonal views once preparation is complete — as I have done for other skulls.)

One of the many things that’s impressed me about this badger is how very much meat there was on its skull. I kept it, or most of it, and now you have the privilege of seeing the skull and its soft-tissue together:

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This is dramatically different from how we think of heads, or at least of how I do. I think this is because when we hear “skull”, we’ve been conditioned by years of Scooby Doo and Indiana Jones to think “human skull”. And I think that human heads much more closely match the profile of their skulls than those of badgers do theirs.

Of course this is just another way of saying that there is a lot more muscle on a badger skull, which is another way of saying that this is a seriously powerful animal. I know I keep making this point, but I think it’s a point well worth making. The world has had quite enough of this kind of thing (from here):

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And its time that we all started to give badgers the credit they deserve. They are basically small bears with misleadingly endearing facial coloration.

(BTW., when I say that I kept the meat, I mean that I kept it until I’d taken that photo. Then I threw it away. I’ve not kept it permanently, I’m not a sicko. No, I’m not.)

I leave you with one of the less successful old music-hall jokes:

  • First man: I say, I say I say! What’s the best way to remove the brain from a dead and partially cooked badger skull?
  • Second man: Actually, there is no good way. The best I’ve found is to shove a chopstick through the foramen magnum, swirl it around to break up the tissue, then shake the bits out and repeatedly rinse.
  • First man: That’s disgusting.
  • Second man: I never said it wasn’t.

Here is the residue, in our sink:

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Fiona, if you’re reading this: I promise I will have this all nicely cleaned up before you return from your parents’ house with the boys.

(Did I mention that Fiona had taken the boys to her parents’ house? It’s not because of the dead badger. It’s just coincidence. I think.)

 

Over the last couple of weeks, I’ve been fortunate enough to acquire two medium-sized native mammals, both roadkill specimens in good conditions: a fox and a badger:

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But I’ve found from bitter experience that prepping out the entire skeleton of good-sized animals like these is a lot of dirty smelly work. So I decided to make things easier on myself by only prepping the skulls of these two.

Step one: remove the heads.

What follows is not pretty. Parental advisory: you should avoid this post if you feel a misguided sentimentality about the already-dead corpses of deceased animals.

I considered several approaches, as recommended by commenters on this blog and people on Twitter, but ended up taking the butcher’s approach — mostly because I have a good, sharp knife, but lack some of the tools needed for other approaches.

I took on the fox first. I cut through the skin surrounding its neck, and peeled it back far enough to reveal the neck musculature:

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From there, it was pretty easy to slice away the muscles down towards the vertebrae — but impossible to get right to the vertebrae themselves, because they’re surrounded by gloop including not only muscles, but ligaments, fascia and tendons:

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I’d hoped to be able to feel my way to an intervertebral joint, and ease it apart with the knife. But that turned out to be difficult. It was also going to need a lot of force, and I was worried that down in among all that gloop, I might slip and cut myself.

So I used our the axe we use for chopping firewood. It would have been terrible for dealing with the flesh, but it was fine for the bones:

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Then it was the same procedure for the badger. I started by cutting a ring around the skin of the neck and peeling back.

Straight away, it was obvious that the badger is a much more serious piece of kit than the fox. It’s not as long, but it’s heavier, and much more muscular, and it has way tougher skin. I don’t know if foxes and badgers ever fight, but if they do, my money is on the badger every time. It would bite much harder and its claws are epic, too. The only thing the fox would be better at is running away.

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Then, as with the fox, I sliced away the meat till I reached the bony core of the neck:

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And again, the axe finished the job. I was left with a pair of decapitated corpses:

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And, more importantly, a pair of heads:

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Also, some evidence of my activities in the bloodstained chopping block. I hope the neighbours don’t see this and leap to the wrong conclusion:

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What to do with the sadly unloved postcrania? I have no further use for them, so I decided to bury the bodies. I went down to the bottom of our garden, only to find all the sheep in the adjacent field coming over to see what I was doing:

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Best stay back, sheep! Or you could be next!

I dug a hole, which is a lot more work than it looks. Predictably, given than I am England during what passes for springtime, it suddenly stared hailing while I was digging. But eventually, I was done:

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In went the postcranial pair:

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And pretty soon, you’d never have known anything had happened here.

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Next time: exciting adventures with the badger head!

The pheasant comes apart

March 26, 2016

A couple of weeks ago, I was given a pheasant, which I reduced to science and food. When we last saw it, it was down to a skinned and partially defleshed head/neck and feet. It’s been through a couple of defleshing rounds since then, and today I was able to take it fully apart:

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At the moment, the bits are laid out on this plate, drying. Small amounts of soft-tissue remain (and more on the second foot), which may need the attentions of invertebrates to fully clean.

It pains me to admit, but even though I have kept the cervical vertebrae, for most people the skull will be the interesting part. Here it is in a little more detail, disarticulated into about ten units. The mandible is to the right of this image; the rostrum to the left of it, and the main cranial section to the left again:

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To the sides are the bones that laterally connect the rostrum to the braincase: zygomatics, quadrates and what have you. They are laid out roughly in the right positions, though the two quadrates may have been switched. Once everything is clean and dry, I’ll glue it back together, using my ostrich skull to help guide me.

The feet are trickier. Here’s the one I took apart:

 

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At the top of the photo, you see a mass of ossified tendons, which operated the toes from more proximal areas. This is how all bird feet work, and it’s such a great scheme that it seems weird everything doesn’t do it.

Below these, we have the tarsometatarsus to the right, and the four digits to the left. Each digit has its phalanges in the right order, but I don’t know what order the digits themselves should be in. To help me get that right, I pulled out of prepping the other foot down, hence its current semi-zombified state:

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I’m hoping it’s still intact enough to guide me as a reassemble the bones of the other foot. (Once that’s done, I may also take this one to completion, or I may decide that one pheasant foot is enough.)

Anyway, it’s nice to be progressing this specimen. Next, I need to figure out the best way to decapitate a medium-sized mammal (like a fox or badger) without damaging the skull, and using no special equipment.

The process of reassembling my cat skull continues. I now have the sphenoid and both nasals now back in place, and the time has come for the now-traditional multiview. (Previous examples: pig skull, wallaby skull, sheep skull.

Click through for seriously high resolution (9602 × 7642).

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And here it is on a black background:

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As though you need to be told: the top row shows the dorsal view, the middle row (from left to right) shows posterior, right lateral and anterior views, and the bottom row shows the ventral view.

Enjoy!

Regular readers will remember that I recently fished my cat skull out of the tub where invertebrates had been hard at work defleshing it, and put it to soak — first in soapy water, then in clean water, and finally in dilute hydrogen peroxide. It was in a pretty terrible state, having either been smashed by a car, or damaged by my rather unsophisticated process of removing the head from the torso. Here’s a reminder:

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After bleaching in H2O2, the skull parts looked much better, but were still very delicate. Here is the main portion of the cranium, missing the braincase and the right upper jaw, upside down, in right posteroventral view.

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Putting it back together was difficult. I am using regular water-soluble wood glue, largely so that if I make a mistake I can just soak the wrongly-joined bits apart and try again.

I started by gluing the braincase (at the top of the plate in the first picture) onto the back of the main cranium piece. Unfortunately, as you’ll see below, I wasn’t able to get a very clean join — I can only assume that one or other part was slightly distorted by whatever force broke the skull apart. Still, having done that, I had a better platform to reattach the right upper jaw (lower left of the plate). I was then able to reattach the broken-off part of the right zygomatic arch (at about 4 o’clock on the plate, just to the right of the lower of the two dentaries, and below a vertebra). It didn’t fit quite right, but what can you do? FInally, I was able to reattach another small piece — at 6:30 pm on the plate — which I think is part of the left auditory bulla.

That gave me a workable cranium (though I have some bits left over — see below.) It was time to repair the right dentary. Its articular cylinder (not really a condyle, despite its name) had somehow got blasted off, as had its retroarticular process: it was quite satisfying to figure out how those Shards Of Mediocrity fitted onto the main part of the dentary.

With that done, I had to glue together the two dentaries. That’s hard to do: it’s awkward to brace them in position for the glue to set, and difficult to get the angle between the two bones correct so that the two articular cylinders both sit neatle in their receptacles in the cranium. Here’s the solution I came up with:

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I rested the cranium upside down, covered the jaw with some thin, pliant plastic (actually a sandwich bag) and used the cranium itself as a perfectly proportioned brace to hold the dentaries in place. Then I was able to glue them more or less correctly, and to reinforce the joint with more glue once the first lot had set.

I’ve still not got it quite right — the mandibular symphysis is wonky — but I think it will do. And if I change my mind, I can always soak the mandible apart and try again.

(As a matter of fact, I’d already done that once, having initially glued the dentaries together at the wrong angle, so that the assembled mandible was too narrow, and wouldn’t articulate properly with the cranium.)

So now I have a pretty good mandible and cranium, as well as the first five cervical vertebrae (all but one of the postzygs of C5, which was lost in the head-removal process.) Here is the whole thing, put together, in dorsal view:

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(You can see where the left zygomatic arch is damaged: the bones are not articulating correctly, as they do on the right.)

And here is the same assembly in left dorsolateral view:

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And finally, the skull in anterodorsal view:

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Note that the left canine is truncated. I am completely certain that this, at least, is not my doing, and must be damage that was done in life. Note, too, how the mandible is visibly wonky from this angle. Hmm. Maybe I will reset it again.

At the end of this process, I have a pretty nice cat skull. Unfortunately, I have seven shards left over, none of them more than about fifteen millimeters long. Here they are:

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I’d welcome any help in figuring out what these bits are, and where on the skull they should be reattached. I don’t want to just throw them away. Click through for much higher resolution to get a better idea of what’s what. The top right piece is such a weird shape that someone must know what it is. The two peices at bottom right seem to be pairs, but I don’t know what they are a pair of. The rest? No idea.

I leave you with the dorsal view again, but this time in glorious 3D for those of you who have been wise enough to get some red-cyan 3D glasses. (Seriously folks, they’re like fifty cents a pair. Just get some. You won’t regret it.)

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Some time soon: those first five cervicals in more detail.

Just under a year ago, the children across the road, who know I’m interested in comparative anatomy, told me that they’d found a dead cat by the side of the road, and asked whether I wanted it. Silly question, of course I did!

I’ve learned from bitter experience that prepping the whole skeleton out of an animal is a very time-consuming process — so time-consuming that I usually just don’t get around to it. This time, I thought I’d just do the skull. So I removed the head (not a pleasant process) and discarded the body.

I did the usual sequence of simmerings with the head, peeling off the skin and fur, then removing muscle, till I was down to just bone, gristle, and the hard-to-remove bits of soft tissue that always adhere in one place or another. At that point, I left the bones in a plastic tub in the woodshed, with a couple of holes in the lid so that invertebrates could get in and deal with the remaining gloop.

Yesterday I had a look (and a smell), and it seems all the soft-tissue is gone, thanks to the hard work of the tiny collaborators who never make it into the acknowledgements. So I soaked the skull pieces in soapy water for a day. Then today, I rinsed them off and left them to soak in pure water for a few hours. Finally, I changed the water, and added some H2O2 to degrease the bones. They are now foaming away merrily. Tomorrow I’ll take them out, rinse them off one more time, dry them, and see what state they’re in.

Here’s how they look today, after rinsing:

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And here is a closeup of a mandible (slightly foreshortened):

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“But Mike”, you ask, “Why is it in so many pieces?”

I actually don’t know. As I was taking the head apart, it seemed to be whole, but as it got down to the raw bone, it was apparent that the skull was very badly damaged. In the picture above, the main part of the cranium is upside down, half way down the left hand side. Below it is the rest of the cranium, the left side of the upper jaw. Above that is the back of the cranium, most of the braincase. The whole thing just came apart into three pieces — and not along sutures. This is breakage.

I’m not sure how it happened. At first, I thought it must be how the cat died — maybe struck a glancing blow by a car. But I increasingly wonder whether I stupidly did this myself in the process of removing the head from the torso. (I did not use a scalpel.)

Anyway, we’ll see how well the pieces can be reassembled once they have dried out. I’m optimised that I can still wind up with a pretty good cat skull.