Tag Archives for bone

Friday mystery object #527 answer

Last week I gave you this skeleton from the stores of the Dead Zoo to have a go at identifying:

The comments came flooding in, with some slightly off and some very much on target.

The robust skeleton and stocky build of this animal, combined with some interesting bony processes – especially in the pelvic region – offered up some pretty good indicators of the type of critter we’re looking at.

The forward-facing processes of the pelvis were initially mistaken for a baculum, but on a closer look their dual nature becomes more apparent:

These are epipubic bones, which aren’t found in Placental mammals – but this is definitely a mammal – so this is either a Marsupial or Monotreme.

The lack of a skull makes it a little harder to immediately figure out what this might be, but the feet are useful – very useful in fact:

These look like the feet of a digger with those big, robust, triangular claws – but not just a burrowing digger like a Wombat – more like an ant and termite specialist whocan break open their nests. That offers a key clue.

This is the skeleton of a species of spiny anteater – one of the four species of Echidna. The feet actually offer a further diagnostic clue to the species, since most species have five claws, while just one has three – the Three-toed or Western Long-beaked Echidna Zaglossus bruijnii (Peters & Doria, 1876).

This particular specimen was originally on display in the Dead Zoo under its old name Pro-echidna Bruijnii:

Photo of Three-toed Echidna skeleton NMINH:1883.285.1 at the National Museum of Ireland – Natural History taken by Illustratedjc, 2015.

The specimen has been taken off display along with everything else in the building over the last year or so, in preparation for a big refurbishment project.

When it was decanted, along with skull, the fragile right-hand-side rear limb was removed. In the photo above you can see where a claw is detaching – possibly as a result of incorrect foot positioning on the mount (Echidna feet point sideways and backwards, which seems to have confused some mounters). In other places, cotton tape was used to stabilise some of the more wobbly robust elements.

Being able to work through items like this while they’re in storage will be helpful, since it will allow us a chance to remove the worst of the dust from what may have been 140 years of display, and to make some small repairs to things like the detaching claw so it doesn’t get lost. Changing the foot position may be a bigger job, but it’s something to consider.

So while the Dead Zoo may be closed, we’re keeping busy checking the condition of the other 10,000 object we had on display, and working out what we need to do to put them back!

Friday mystery object #523 answer

Last week I gave you this mystery mandible to help me identify:

It was found in a box of mixed shells and bony fragments, with no label, and nothing to offer a clue to its origin. This is very unusual, since these sorts of boxes of miscellany were mainly addressed years ago, but this one was well tucked away and somehow escaped being dealt with.

It’s fairly easy to recognise this as being the right mandible of some kind of cat. The Felidae have a reduced tooth count, with those hyper-carnivorous bladed premolars forming a meat-shearing carnassial row that’s very distinctive. So that’s the easy bit done.

The hard bit comes next, since the cats all share this same dental configuration, making the specific kitty in question a bit harder to narrow down. However, the size is a useful clue. This is much too big to be something like a Domestic Cat, Serval or Ocelot, but it’s also too small to be one of the big Big Cats – like the Lion or Tiger:

Tiger skulls facing off – the scale of these skulls is much greater than the mystery mandible

This leaves some of the medium-large Big Cats and perhaps a very large Small Cat (i.e. the Cheetah). Let’s start by ruling out that last one – the size is still a bit on the big side, but also the Cheetah has a more gracile coronoid process that curves, and a relatively shorter toothrow. Pumas also have a more rounded coronoid process.

The Jaguar also has a more rounded coronoid process, and has a more robust mandible, that’s just built thicker to deal with the high bite forces these cats generate:

That leaves us with the Snow Leopard and the not-snow-Leopard, both of which have the more pointed coroid process that we see in the mystery object. However, the Snow Leopard has downwards inflected angular process, that’sI suspect may relate to the increased gape needed to use the excessively long canine teeth in this species:

The answer to last week's mystery mandible
Snow Leopard skull, showing the hypertrophied canines normal in this species.

So, by a process of elimination, we’re left with Leopard Pathera pardus (Linneaus, 1758). This species varies significantly in size and the morphology can be quite variable, since the species has a wide distribution, from Eastern Russia to as far West as Senegal.

This actually reminds me of a very similar mystery object from the Grant Museum of Zoology that I shared 10 years ago, so I’ hope that provided something useful for reference so I’m glad I trawled through some of my past posts to help solve this one. My thanks to everyone who offered their thoughts on this one – it’s great to see so many of you come to the same conclusion!

Friday mystery object #522 answer

Last week I presented this mystery bone from the Words on the Wave exhibition at the National Museum of Ireland on Kildare Street:

The bone is over a thousand years old, so it’s unsurprising that a few of the processes that could be useful for identification have been worn down a little:

That said, there was plenty of information remaining to allow several of you to identify the animal, bone type and side of the animal this is from. Adam Yates was first to the comments and he also left a very helpful Toot on Mastodon, detailing the diagnostic features:

@mike @PaoloViscardi The prominent third trochanter and really well-developed supracondylar fossa on the lateral caudal surface at the distal end of the shaft should get you there. You won't have to look beyond familiar farmyard beasts to find it.

For me, the supracondylar fossa on the lateral caudal surface is the instant give-away. For those who don’t speak anatomese, that’s the bit that flares out from the side of the shaft of the bone (which is actually missing a bit in this example).

This is a feature I always associate with the Perissodactyla (the tapirs, rhinos and horses), and this one is nowhere near robust enough for anything other than one of the horses. It’s also fairly small (although the lack of a scale bar doesn’t make this obvious).

This a left femur that I suspect is from a Horse Equus ferus caballus Linnaeus, 1758, but it could also be from a Donkey Equus africanus asinus Linnaeus, 1758. It can be tricky to tell these species apart, especially when the bone is a little worn down and you only have a few photos to work from – so best to err on the side of caution and leave it at an identification of Equus sp.

If you’re in Ireland and wanted to take a look at this object – and a selection of remarkable mediaeval manuscripts from the Abbey of St Gall, Switzerland, some of which are returning to Ireland for the first time in 1000 years – you have until the 24th of this month, I’d definitely recommend it!

Friday mystery object #522

This week I have another bony mystery object for you:

This one is currently on display in the beautiful Words on the Wave exhibition at the National Museum of Ireland on Kildare Street, but the focus is on the inscription on the bone, rather than the species the bone came from:

So, I’d love to hear your thoughts on what this is? Have fun with it!

Friday mystery object #521 answer

Last week I had a genuine mystery object for you to identify that was freshly dug out of the ground:

While there were a few suggestions of baked goods on social media, plenty of you spotted what it actually is – with a nod to Adam Yates who was first with the correct identification.

The side view is probably the most useful for setting context, as it shows the smooth curve of the head of an articular surface, with an adjacent tuberosity (or sticky-up-bit, if you prefer):

This is what you expect to see at the proximal end of a humerus (that’s bit that works with the shoulder). It’s pretty big – the scale bar is 8cm and the head of this humerus is a good bit wider across, so that also tells us something.

Another key observation comes from the underside of the humerus head:

You can just make out a rugose pattern on the underside of this piece of bone, which tells us that this is an unfused epiphysis that has become detached from the rest of the humerus. That means the animal that this piece of bone came from was young enough to still be growing, as the bones hadn’t fused.

All of that information leads us to the conclusion that the animal this piece of humerus came from was large, but still young. For me, that says that this humerus is from a Cow Bos taurus Linnaeus, 1758.

I suspect this mystery object represents the remains of a Victorian meal, based on where it was found – just under the floor of the Dead Zoo. It came to light during the investigation works on the building, which are currently underway. The building work started in 1856, so that gives us a good idea of when this beef shoulder was probably eaten.

Friday mystery object #514 answer

Last week I gave you another guest mystery object from regular contributor Andy Taylor FLS FBNA:

Image by Andy Taylor FLS FBNA, 2025

This proved to be a tricky challenge. The large size and the lack of a halux (the rear-facing small toe found in many birds) makes this seem like the feet of some sort of Ratite, which is the group of birds that includes a variety of flightless examples, including Ostriches, Emus, Cassowarys, Rheas, and Kiwis – many of which lack the hallux.

Image by Andy Taylor FLS FBNA, 2025

However, these feet do not belong to a Ratite – and in the comments, many of you seemed to notice that there was something funky with the arrangement of the toes and bones that may have offered a clue to indicate that fact. Even though they’re not from a Ratite, there are some useful pointers that can be taken from the similarities, since form follows function and if we know Ratite feet can look similar to these, then perhaps it’s worth asking “why is that?”

Many (although not all) Ratites have three forward-facing robust toes, although the Ostriches are a bit of an exception, as they only have two toes per foot. In the evolutionary push to be fast on your feet, too many toes can make you slow – just look at how horses have lost all but one of theirs.

Ratites also lack a hallux, and their claws don’t curve. These features all reflect the fact that Ratites don’t perch on branches, they’re heavy, and they spend most, if not all, of their time walking around on dry grasslands (actually, this isn’t true for Kiwis or the extint Moas that have more scrubby or habitats, but these Ratites do have a hallux). These are all useful things to consider when thinking about potential species that these feet could be from.

If you think of large and heavy birds that don’t perch and have a grassland habitat the list of possible options gets narrowed down quite quickly. Sereimas and Secretary Birds are out, as they have a hallux and more curved claws. Storks, Megapodes and Galliformes all also have a hallux. But one type of bird matches the description very well – the Bustards (or Otididae if you prefer).

The size means it must be one of the larger species of Bustard, but I suspect that it would be difficult to confirm the identification to species level without good quality reference material, since there are quite a few species. But in this case we’re luck to know the species, since Andy has the information – these feet belonged to a Great Bustard Otis tarda Linneaus, 1758.

It’s a species I’ve talked about before in a previous post and I really appreciate Andy sharing the images and information from his collection, and all the thoughts and comments that came in about the mystery object from the community here on Zygoma. Thanks for taking part!

Friday mystery object #514

This week I have another guest mystery object for you from regular contributor Andy Taylor FLS FBNA:

Image by Andy Taylor FLS FBNA, 2025
Image by Andy Taylor FLS FBNA, 2025
Image by Andy Taylor FLS FBNA, 2025

I’m keen to hear your thoughts on what the owner of this magnificent pair of feet might have been in the comments below. If it proves very difficult then myself of Andy might be tempted to offer up some clues, but I have a suspicion that some of you might work it out yourselves. Either way, I hope you enjoy the challenge!

Friday mystery object #513 answer

Last week I gave you this mystery object found by the family of one of my colleagues to have a go at identifying:

Image by Andrew Brady, May 2025

Adam Yates got the ball rolling with some key observations about this skeletal element that provides a handy set of clues to look for when assessing vertebra:

The element is easier than than the taxon. It is a thoracic vertebra from a mammal because it has zygapophyses (so therefore not a fish), flat centrum faces (so therefore not bird or reptile), and rib articulation facets (so therefore not from the neck, lumbar or tail regions). Which mammal is less easy, I’m pretty sure it is isn’t a relative of flipper, but that’s all I’ve got now.

Adam was also right in flagging that it’s not from a cetacean – their transverse processes are longer and less robust than we see in this mystery specimen. However, this bone was found on the beach on Achill Island, so there’s a good chance it’s from a species that’s frequently in the water.

Then Joe Vans, Kat Edmonson and Adam got stuck in with consideration of the possible species and specific thoracic vertebra, and as part of that there was reference to images from John Rochester’s Flickr pages. As far as I’m concerned, John’s pages are some of the best resources available for osteological comparison and I use them regularly.

The discussion ended up converging on the 5th thoracic vertebra (or T5 as it would be commonly referred to) of a Harbour Seal, based on specimens imaged by John here: https://www.flickr.com/photos/jrochester/14181517647 – best compared to this image of the mystery specimen:

Image by Andrew Brady, May 2025

This could well be correct, but I personally think it may be from a different species of seal. The size is fairly large (based on the hand that provides some scale), yet the epiphyses of the articular surfaces are not fully fused, suggesting that this is from a subadult animal:

This suggests to me that the animal had some more growing to do before reaching full size, which may impact on some of the features, but it also makes me think that the vertebra is probably on the smaller end of the size range for the species.

For me that would suggest a Grey Seal Halichoerus grypus (O. Fabricius, 1791) and looking at another of John’s pages: https://www.flickr.com/photos/jrochester/24441096790/in/photostream/ I would expect it to be in the T6 or T7. This also tracks for me in terms of the shape of the neural canal, which seems narrower and taller (generally more square) in the Grey Seal compared to a broader and perhaps more triangular neural canal in the Harbour Seal.

I suspect a measurement of the size would help confirm one way of the other, so I’ll see if I can get that to be sure. I hope you enjoyed the challenge of working this out, and I’d love to hear your thoughts if you think it could be something else!

Friday mystery object #513

This week I have another guest mystery object for you, found on a beach by the family of one of my museum colleagues:

Image by Andrew Brady, May 2025
Image by Andrew Brady, May 2025
Image by Andrew Brady, May 2025
Image by Andrew Brady, May 2025
Image by Andrew Brady, May 2025

Let me know your thoughts about the species, where in the body this particular bone came from, and any other deductions you might have about the animal? I look forward to seeing if you agree with my thoughts!

Friday mystery object #506 answer

Last week I gave you a charismatic critter to have a go at identifying:

I only provided a close-up of the face of the specimen, since I didn’t want to make it too easy, and when you see the whole skeleton it’s pretty obvious which animal this is from:

This is, of course, a Pichiciago or Pink Fairy Armadillo Chlamyphorus truncatus Harlan, 1825.

These tiny Argentinan armadillos are incredibly cute, with their silky fine hair and huge forefeet with massive claws (all the better for burrowing, my dear), although it’s a little hard to see that from the skeleton, so here’s this specimen’s skin:

Several of you worked out what this was, but Adam Yates was the first to post the answer – so well done Adam.

One of the observations from Kat Edmonson was about the protuberences from the top of the skull – for which I’ve yet to find any functional explanation. It may be as simple as providing a structure to support the armoured shield over the head area, but it’s not present in other armadillo species, so I’m not sure how this would work.

Since this species burrows and spends a lot of time in the sand hunting for ants and insect larvae, it may be that the bony protrusions help channel sound to help with prey detection and predator avoidance – but that is pure speculation. I’d love to hear your thoughts on this feature!

Well done to everyone who worked out the identity of this mystery object – while it may be distinctive, it’s an unusual wee beastie.

Friday mystery object #501 answer

Last week I gave you this piece of bone to have a go at identifying:

I have to admit, it’s even harder than I thought it would be, so I should probably apologise about now! Adam Yates got as close as I think is really achievable from just this photo, dropping the clue:

He was very stern and he flipped me the bird when I suggested it looked like a ship: galley-form you could say.

This of course is a hint that the bone is a sternum from a bird in the Order Galliformes. Adam then followed up with:

I’m grousing because its proving difficult for me to identify beyond tribe level

This points us in the direction of the Tetraonini – the tribe within the Galliformes that contains the various species of Grouse. I’m entirely in agreement with Adam. Bird sterna are quite characteristic, as you can see from the gallery of different sterna below:

The chicken sternum in the images above (first one pictured) is the closest in form to the mystery object. The Galliformes have a tiny flat section to their sternum, with long processes coming off to support the pectoral muscle, unlike most other birds which have large flat sections to accommodate the muscle. This likely reflects the low use that the flight muscles tend to get in the Galliformes, which generally (although not exclusively) avoid flying if possible.

The fact that the sternum is showing its ventral side and it’s broken in several places, it’s really not feasible to definitively identify it to species based on the available information.

However, I have some additional context, because this piece of bone is actually just a small piece of set-dressing in a diorama from the Dead Zoo, depicting a Peregrine Falcon nest:

In this diorama the Peregrine chicks are being served a tasty portion of Red Grouse:

Since the bones of the Red Grouse would have been removed as part of the taxidermy process, there’s every chance that some of those bones used in the dressing of the diorama may have come from the specimen, although I’m sure there would be plenty of bones from Pheasants and other Red Grouse available in the taxidermy studios of Williams & Sons, where this was made.

So well done to everyone who got as far as Galliformes – I promise it won’t be quite so difficult next time!

Friday mystery object #489 answer

Last week I gave you this specimen from the Dead Zoo to have a go at identifying:

It didn’t take long for Chris Jarvis to drop a great clue to the correct answer, and it seems that overall it was a bit of an easy one for quite a few of you. I admit that I’m not overly surprised by that, since it’s pretty distinctive.

The scapula is long and curved, the humerus is relatively short and robust, the radius and ulna are robust and quite flattened, as are the digits on that wide and splayed-out hand. All of these elements add up to a flipper shape, but unlike the flipper of a cetacean or seal, it has quite short digits.

That’s because this is the left arm of a slow-moving aquatic mammal that plods along under the water (as much as plodding is possible whilst being underwater), rather than a hydrodynamic fast-swimming beastie with a flipper shaped to cut through the water.

There are still a few possible species that fall into this category, but of then all, there is only one with such a curved scapula shape – the Dugong Dugong dugon (Müller, 1776).

Dugong (Dugong dugon) underwater. Image by Gejuni, 2015

I picked this mystery object because it’s from one of several specimens that we’ve been working on recently, in preparation for transport out of the Dead Zoo, as we prepare for a major capital project on the building. The limbs, skull and tail were removed and the vertebrae and ribs stabilised in a structure that we call a “stillage”:

With enough wrapping and packing this specimen will be ready to crane out of the building in the near future, and it’s just one of several thousand specimens that will be making the move. If you’re interested in hearing more about the project, you can listen to an interview I did recently with Sean Moncrieff on NewsTalk.

I hope you enjoyed working out what this limb belonged to, and I suspect that there will be more tales (and possibly tails) from the decant coming up in future posts. Happy Friday!

Friday mystery object #482 answer

Last week I gave you this specimen to identify, which came to me as an enquiry, after being found in the sea by a fisherman:

I don’t think it posed too much of a challenge, despite some damage, which has left sections looking a bit different to usual for this skeletal element – which is a section of the lower jaw or mandible.

This piece of the mandible includes the ramus (the rear part of the jaw behind the toothline where it rises up), coronoid process (the section of bone that rises up through the inside of the cheekbones, and where the temporalis muscles attach to power part of the action of the jaw) and the mandibular condyle (the hinging articulation point where the lower jaw meets the rest of the skull).

The scale bar shows that it’s fairly large, and the shape of the coronoid process and articular condyle are what I would consider to be quite distinctive to herbivores, since a long ramus isn’t well suited to resisting forces from struggling prey or meat-cutting bites.

From this point I find it’s useful to check an image I prepared earlier (and by earlier, I mean about 10 years ago):

A quick comparison makes it fairly clear that the mystery object is part of the mandible of a Cow Bos taurus Linnaeus, 1758, based mainly on the shape and orientation of the mandibular condyle.

There are of course species that could possibly turn up in Irish waters, that aren’t on my mandibles photo – in particular, Giant Deer, which Ireland seems to have a lot of. However, I have easy access to those specimens in the Dead Zoo and they have a similar mandibular condyle orientation to a Red Deer.

So well done to everyone who worked it out – I hope my explanation of the anatomy of the rear part of the mandible makes sense and maybe offers some pointers for identifications you might be faced with in the future!