Tag Archives for teeth

Friday mystery object #455 answer

Last week I gave you a challenge to get your teeth into:

As I suspected, everyone managed to figure out what type of animal this is, since these teeth are quite distinctive (as mammal teeth often are).

To start with, there are canines and incisors in the premaxilla (the top jaw). These are missing from things like cows, sheep and deer. So it’s not one of them. The premolars are adapted to grinding rather than cutting, so it’s not some kind of pig or carnivore.

The molar teeth are low-crowned, unlike the teeth of grazers like horses which are high crowned, to cope with the wear and tear of silica-toughened grasses. This suggests an animal that browses on softer vegetation. Also, the lophs (those ridges of enamel that join the tooth cusps) are well defined and quite distinctive in their shape. That rules out most other herbivores, including the camels and their relatives.

It turns out that this is a species that I’ve featured on the blog before (although it was almost 11 years ago!) Not a Baird’s Tapir as most people thought, but a Malayan Tapir Tapirus indicus Desmarest, 1819.

I think it’s understandable that nobody got the correct species, since the specimen is a subadult (check out the molar in the jaw that’s still developing) which will somewhat alter the proportions compared to an an adult – especially considering the photos I gave you were restricted to the teeth and missed all the useful features of the rest of the skull.

So well done to everyone who worked out that the teeth belonged to a tapir!

Friday mystery object #455

At the Dead Zoo we get quite a lot of enquiries asking for identifications, and many of these requests are for teeth. Mammal teeth are usually quite distinctive – for instance, tooth morphology underpins a lot of small mammal palaeontology as teeth preserve well and can be identified to genus/species with reasonable accuracy. Additionally, they can often give a good indication of diet.

With that in mind, I took a photo of some teeth that I found in the collections, to see if you can work out which species they belong to:

For the mammal fans among you this is probably way too easy, so please try to keep your answers a little bit cryptic, just so that everyone has a chance to figure it out for themselves. Have fun!

Friday mystery object #444 answer

Last week I gave you a couple of skulls from the collections in the Dead Zoo to have a go at identifying:

It’s pretty obvious that they are rodents, based on those paired incisors. But there are a lot of rodent species out there…

These are small and, based on the size, we can immediately rule out all anything bigger than a Brown Rat. The anterior portion of zygomatic process, where it meets the maxilla (the front parts of the cheek bones) are broad and triangular, narrowing to very fine arches where it meets the temporal porocess (the rear part of the arch of the cheek bone). This is something I associate with voles.

The teeth are also distinctively ‘voley’ with their zig-zagging cusps.

There are still a lot of vole species out there, but if you’re familiar with identifying specimens from owl pellets in the UK you’ll probably recognise that the specimen on the left has a very distinctive second molar, with a small fifth cusp. This is a tell-tale indicator of the Short-tailed Field Vole Microtus agrestis (Linnaeus, 1761), while the more rounded cusps of the specimen on the right are more in keeping with a Bank Vole Myodes glareolus (Schreber, 1780).

So congratulations to Chris Jarvis in the comments, and to the Scarborough Museum and Galleries Collections Team on Twitter, who managed to leave sufficiently clear but cryptic clues to the identity of these skulls:

I hope you enjoyed these smol skulls and the pointers provided to separate them.

Friday mystery object #378

This week I’ve gone for a slightly more artsy image for the mystery object than usual:

You can click on the pictures to get a large version, which you might find useful.

I foolishly forgot to measure the specimen or include a scale bar, so I’ll update with a length as soon as I get back to the specimen. Sometimes it’s nice to rely just on morphology, so let’s see if anyone can work out what this is before I provide more information. [UPDATE: it’s 84mm long]

Have fun!

Friday mystery object #326 answer

Last week I gave you this dissected mandible to have a go at identifying:

20180322_162222-01.jpeg

I thought it might be fun to get a poetic response and I wasn’t disappointed. There were some great efforts and I thoroughly enjoyed unpicking the clues from the verses people crafted in response. Of course, a poetic soul is only so much use in this game – you also need to work out what it is.

Bob Church was the first with a bardic response that was unambiguously on target for the identity of the mystery specimen:

Though the bone’s a disaster
There’s enough left to answer
What this rolly polly animal could be
It might sound a bit funny
But mix a turtle and bunny
And you’ll find the bowled over family

Of course, if you mix a turtle and a bunny you get something that looks like the artistic creation by John Tenniel in 1865 to illustrate Lewis Caroll’s Mock Turtle from Alice’s Adventures in Wonderland:

alice_par_john_tenniel_34

Gryphon and Mock Turtle with Alice, by John Tenniel in 1865

The animal in question is actually remarkably similar in appearance:

9-banded Armadillo by Ereenegee, 2011

9-banded Armadillo by Ereenegee, 2011

It’s the Nine-banded Armadillo, Dasypus novemcinctus Linnaeus, 1758, a decidedly odd animal that lives in South, Central and southern parts of North America.

Most mammals have well differentiated teeth, so the homogeneity of these in shape (or homodont condition) suggested that you were dealing with something a bit unusual, with simple peg-like teeth, open roots and no enamel. That makes the mandible quite distinctive, even with some missing teeth.

The one slightly confusing thing about this half a jaw is that it appears to have tooth holes (or dental alveoli) for 10 teeth (as recognised by salliereynolds, who also got the identification right), but armadillos are only meant to have eight teeth in each side of their upper and lower jaws.

I thought this difference might throw you off the Armadillo scent a bit, but clearly I was wrong. The difference in this jaw will probably be because it comes from a young animal which still has milk teeth (or the alveoli for them) that aren’t all replaced by the adult teeth.

These insectivorous armoured animals are unusual in a variety of ways beyond their dental idiosyncrasies. They have imbricated bony nodules or plates embedded in their skin (or osteoderms) that forms a tough armour:

mysob3a

Dorsal view

mysob3b

Ventral view (width ~5cm)

They also consistently give birth to four offspring every time, originating from a single egg that splits into four. So every Nine-banded Armadillo has three identical siblings. I think this fact alone qualifies them as one of the weirder animals out there.

More mysteries next week!

 

*Juliette Kings may have got in with the first identification, with reference to the Armadillo’s habit of jumping straight up in the air when alarmed and occasionally screaming, but it sounded a bit more like she was suggesting Goat.

Friday mystery object #264 answer

Last week I gave you a tricky mystery object in the form of a dusty bag:

Bag o-bones

Of course, I’m not truly that mean, so I also provided a characteristic part of the specimen:

mystery264

Despite being a bit broken, it’s fairly clearly the mandible of a felid, given the shape of that one molar and the limited sockets for the missing premolars, suggesting something with a very reduced tooth count – something that most of you spotted straight away.

The size is a bit small for a Tiger or Lion, it’s a bit big for a Puma or Cheetah and it’s not quite as robust as I’d expect from a Jaguar, leaving us with the likely identification of Leopard Panthera pardus (Linnaeus, 1758). So well done to joe vans and palreyman1414 for ‘spotting’ what it was (terribly pun, I know).

Here’s a nice Leopard skull from the Grant Museum of Zoology collections to give a sense of scale.

leopard

More mystery objects to come from the Grant next week, but if you’d like to see another specimen from the collection, my latest specimen of the week, that looks at the darker side of the Walrus might be of interest.

Friday mystery object #260 answer

Last week I broke the news that in October I’ll be taking on the role of curator at the Grant Museum of Zoology at UCL. Many thanks to everyone for their congratulations and kind comments – it’s wonderful to have so much support!

I’m excited to get started in my new role, but I will be sad to no longer be the go-to person for identifying materials used in the Horniman’s Anthropology collections. This gave me the chance to see some lovely objects, like this little statue:
mystery260
I asked if you had any thoughts on what it might be, and you gave some great answers, mostly involving an ungulate canon bone or metacarpal / metatarsal. However, palaeosam and palfreyman1414 spotted that this isn’t made of bone, while Chris went one better by making a nice reference to ‘Horsing around near the river’ – a reference to the meaning of the name Hippopotamus.

The key to identifying this is to look at the curve of the statue and the view from underneath. That cavity shape (plus the gentle curve) is exactly what you’d expect from the upper canine of Hippopotamus amphibius Linnaeus, 1758 – so well done Chris!

There’s a helpful guide to identification of ivories by the US Fish & Wildlife Service, which is well worth a look to help with this sort of thing. Hopefully that’ll be a helpful resource for my colleagues at the Horniman in my absence… although they know where to find me if they need help in future!

Friday mystery object #243 answer

Last week I gave you this nightmarish looking mystery object to identify:

mystery243

There were lots of great suggestions about what it might be, with most of you in the right area of the animal kingdom with a legless critter in mind. In particular a fairly primitive type, with aglyphous or ‘groove-less’ teeth (as opposed to snakes characterised by having opsithoglyphous or ‘backward grooved’, proteroglyphous or ‘forward grooved’ and solenglyphous or ‘pipe grooved’ teeth).

There were several suggestions of Boa constrictor – specifically the right maxilla (upper jaw), but they have a straighter top to the maxilla and a differently shaped process that connects with the frontal and ectopterygoid bones (check out Udo Savalli’s snake skull anatomy page to see what those terms mean).

Anaconda was also suggested, but the anterior (front) part of  the maxilla is not squared off enough.

Nicola Newton, rachel and Alex Kleine all suggested Python, which is what I think it is. I’m not certain of the species, but it’s definitely a big one – I’m leaning towards the Reticulated Python Python reticulatus (Schneider, 1801).

Just to give you a better idea of which bone it is, here it is compared to the skull of another large Python skull from the Horniman’s collection:

mystery243b

and to give a better sense of scale, here it is with my (fairly large) hand for comparison:

mystery243a

My very rough estimate of the length of the animal, based on other skeletal material I’ve seen, is around 5m – that’s one snake I wouldn’t want to get on the wrong side of!

Friday mystery object #231 answer

Last Friday I gave you this distinctive skull to identify:

mystery231

I knew it would be a bit of an easy one, given the highly unusual teeth, but it seemed too interesting a specimen to not use.

As cryptically suggested by many of you (Jamie Revell, Nigel Monaghan, henstridgesj, rachel, cromercrox, Robin Birrrdegg, Allen Hazen and Crispin), this is indeed the skull of a Crabeater Seal Lobodon carcinophaga (Hombron & Jacquinot, 1842).

Jerzy Strzelecki, 2000

These seals are specialised for catching krill, hence the strange shape and tightly fitting nature of their teeth, which act as a filter to strain the tiny crustaceans from ocean water.

Because these seals live in the waters all around the Antarctic, monitoring their population is particularly difficult, so estimates of their numbers vary considerably, from 2 million to 12 million (which is the more likely figure).

As with most abundant animals they have predators, in particular Leopard Seals. Apparently 78% of adult Crabeaters bear scars of Leopard Seal attacks, which can be seen clearly on the live individual in the image above. Most of the attacks happen before the Crabeaters reach a year old and get a bit too big to be easy prey, but in that first year there is apparently a huge mortality rate, with only 20% of seals making it to their first birthday. Good old Mother Nature is never one for sentiment.

Friday mystery object #207 answer

A very late and brief answer to the last mystery object I’m afraid – hopefully I’ll get back on track soon, once everything has calmed down a bit!

I gave you this object to identify:

mystery207

 

It was a bit of a mean one, since these teeth are mostly broken with several missing. but there were some great answers.

Several of you recognised these as teeth from a juvenile Old World primate, so well done to henstridgesj, Jake and Jakob Ramlau. Jakob also alluded to dogs in his answer and I wonder if he managed to spot that the  primate was a Dog-faced Baboon Papio cynocephalus (Linnaeus, 1766) or Yellow Baboon as it’s also known.

mystery207_full

I’ll take some time to talk about deciduous teeth sometime soon, once I’m able to sit down and get back to blogging properly!

 

 

Friday mystery object #207

This week I have a difficult mystery object for you to have a go at identifying. It was found in a crate of stray teeth and bones that recently came to light and I’m afraid it’s not in the best condition. Any idea what this incomplete run of teeth may have come from?

mystery207

Click for a bigger image

As usual you can put your comments, questions and suggestions below and I’ll do my best to respond as quickly as possible. Good luck!

Oddjects No.1

I’ve been running my mystery object for over three years now and I’ve decided to add another kind of post in order to share some of the odd and interesting objects that I come across as I work in the collections of the Horniman Museum.

To share these specimens I’ve chosen the name ‘Oddjects’ as a portmanteau of ‘Odd’ and ‘Objects’. Here’s the first:

Oddject1

This happens to be a Wolffish (Anarhichas sp.) specimen that was a mystery object back in 2010, but here I just want to use the specimen to capture the imagination and spark discussion rather than provide much in-depth interpretation.

What does this make you think of?

I hope you enjoy the Oddjects I plan to share – if you do I would heartily recommend also checking out the Twitter and Tumblr feeds for the Horniman’s collections review projects as they also share some great objects.

Friday mystery object #175 answer

On Friday I gave you this anthropological mystery object to identify:

I asked you what the teeth might have belonged to and where in the world might this necklace be from.

It’s always a bit tricky to identify worked material as it will often be different from what you’d see or expect in the wild state and you lose the context of the rest of the specimen. Nonetheless, these teeth are quite distinctive to a particular group of animals.

Barbara Powell, 23thorns and Robin got the right general area with suggestions of Islands in the South Pacific, in particular New Guinea. 23thorns also nailed the animal group with his suggestion of  Continue reading →

Friday mystery object #58 answer

On Friday I gave you this skull as a mystery object, dredged as it was from the memory card of my severely concussed camera:

This was a slightly sneaky object, because I had a feeling that quite a few of you would make the same mistake as I did when I first saw this skull, by assuming that it’s from a large rodent. The large front teeth (the incisors) support this, since enlarged first incisors are a feature of the rodents.

Rodents also have a large gap behind those incisors called a ‘diastema’ – which this skull has for the lower jaw (or mandible), but you may notice that the upper jaw has three incisors in the pre-maxilla (that’s bone in the front bit of the upper jaw) before the diastema. This is easier to see in a side (or lateral) view:

You might notice that there’s a small tooth behind the third incisor in the upper jaw – that’s a canine. You might also notice the faint wiggly line in the bone of the jaw just above the canine – that’s the junction (or suture) between the maxilla and the pre-maxilla bones. The canine is the first tooth in the maxilla and all the incisors are in the pre-maxilla (this is the same for all mammal teeth).

Rodents only have two teeth in the pre-maxilla, not six. They also have no canine teeth in the maxilla. That means this mystery object cannot be a rodent. Here’s what a rodent’s diastema looks like (the suture between maxilla and pre-maxilla is really clear in this photo):

Lagomorphs (rabbits and hares) have teeth similar to rodents, except they have an extra pair of incisors behind the front pair in the maxilla – these are called ‘peg teeth’:

Rabbit_peg-teeth

Peg-teeth in a Rabbit skull

Clearly the mystery object has more incisors than this, plus those canines, so it can’t be a lagomorph either.

So what beastie has six upper and two lower incisors? Several of you worked out that this was a marsupial from the dentition (namely Cromercrox, jonpaulkaiser, David Craven and Zigg), but only Prancing Papio and Jamie Revell managed to get it to species, namely the  Continue reading →