On Animal Teeth, or Why I’m Not a Dentist

Since my last post using comparative anatomy was rather popular, I figured I should write a similar post for this week, starting with the most important part of the skeleton for zooarchaeologists (in my opinion) – teeth!

In my experience, teeth are the best skeletal elements to recover. Why? They’re one of the more easily identifiable parts of the skeleton and one of the more variable skeletal elements across different species.

Unfortunately for me, they’re also some of the…well, grossest parts of the skeleton. Nothing will put the fear of root canals and cavities in you like looking at any worn down tooth from a cow or sheep!

Here is a small sampling of teeth from different animals and how you can easily identify them, in very informal and non-technical-sounding ways:

Pig

Pig teeth might be the weirdest looking teeth I encounter regularly (besides my own…and if you’re my dentist reading this, no I will never get braces, I can’t afford them!). The easiest way to ID them is to recognise how similar they look to human teeth…but just slightly off. Basically, I like to say that the molars look like human teeth that have popped a bit like popcorn. Yes, I’m aware of how gross that is – but that’s how I remember them!

Pig Teeth
Yuck – here are the teeth of a domestic pig.

Dog

Dog teeth have a sort of “wave”-like shape to them that makes them a bit distinct. Often, I’ve found that their molars and premolars not as pointed and sharp as a cat’s teeth (see below), but that isn’t always the case, of course. In any case, dog teeth are quite bulky in comparison to cat teeth.

Dog Mandible
A detailed look at a dog mandible (Photo Credit: Melissa Rouge, Colorado State University)

Cat

Cat teeth have a somewhat similar shape to dog teeth, but I’ve found that they are somewhat more pointy than most dog teeth (although again, this may not always be the case). In comparison to dog teeth, cat teeth are also relatively smaller and not as bulky. A larger set of teeth that may look cat-like could indicate you’ve got another member of the Felidade family (i.e; lion, lynx).

Cat teeth
The dainty, pointy teeth of a domestic cat.

Sheep

The easiest way to ID sheep teeth is to check for a “house shingle”-like appearance. I have found that in comparison to animals with similar looking teeth (cows and horses), sheep teeth are also rather thinner. Be careful, though – sheep and deer teeth are remarkably similar in size and appearance!

Sheep Teeth
The maxilla and mandible of a sheep – note that house shingle look!

Cow

As mentioned above, cow teeth are similar in appearance to sheep with a slight “house shingle”-like appearance. However, given the difference in size, cow molars and premolars will be larger and bulkier, usually.

Cow teeth
Compare these cow teeth with the sheep teeth above

Rodents

And finally, some of the smallest teeth you’ll run into: rodents! To be frank, if you find very small teeth, it is most likely from a rodent of some kind. The front incisors may be a bit more difficult to ID if found alone as they are much larger than the other teeth and may be mistaken for a bit of rib bone. These teeth are what create the pattern of gnawing attributed to rodents that looks like long striations or lines on the bone (more on that in a future post!).

Rat teeth
The skull and mandible of a rat – look at that incisor!

If you’re looking for a more in depth comparison of mammal teeth, I would recommend Mammal Bones and Teeth by Simon Hillson (1992). It’s a great guide that I use in my work with some really clear diagrams.

On Seals, the Dogs of the Sea

The other day, a group of archaeologists (myself included) stood around trays of assorted animal bones from a recent surface collection. It was just a cursory glance at the assemblage, but of course the mind immediately starts identifying bones that jump out at you.

“That’s a dog mandible…that’s a cow tooth…that’s bird, for sure…and that’s…a dog too?”

It was a fragment of a mandible that certainly looked like a dog at first glance…and yet, there was something a bit off. After looking at it for some time, it finally hit me: oh, it’s a seal. The dogs of the sea.

Seal and Canine Mandibles

When you start off in zooarchaeology, you start to find big indicators that immediately help you narrow down an identification – little “shortcuts”, if you will. Case in point – identifying seals based on comparing them to dogs.

Above, you’ll see a dog mandible and a sea mandible. Side by side, it’s a bit easier to see the difference between the two. But on its own, it’s not that difficult to mistake a seal mandible for that of a dog. I chalk it up to the teeth shape being very similar, and some slight similarities in the shape of the mandible itself (note – the mandible that was originally in question was smaller than the above mandible, so a bit easier to mistake for a dog!).

So with that in mind, it’s a bit handy to keep that in your mental toolkit. Got a mandible that looks like a dog’s, but something’s a bit…off? Might be a seal!

Seal Skull

Of course, there’s plenty of variation in dog skulls among different breeds that maybe that’s not the best conclusion to jump to, so here’s another tip: check the sort of overall bone there is. Does it look rather porous? Well, that’s an easy sign that you’re dealing with some sort of marine animal! So if you have a mandible that looks dog-like, but has a porous quality to it? Either it’s a mythical sea dog (in that case please send me photos)…or most likely, some kind of seal.

UPDATE: After further conversation with another zooarchaeologist, it turns out that dog mandible might actually be a wolf mandible! Oops…well, point still stands, I guess!

Seal pelvis