Friday mystery object #326 answer

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

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:

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

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:

Dorsal view

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 #326

Yesterday I was doing some work in the gallery of the Dead Zoo and found a specimen that needs a little light repair work to stick teeth back into sockets. I thought it might make an interesting object for you to have a go at identifying:

Any idea what this piece of mandible might belong to? It’s probably a bit too easy for some of the mystery object veterans, so please keep your suggestions cryptic and, if you’re in the mood, poetic.

Have fun!

Friday mystery object #325 answer(ish)

Last week I gave you the challenge of identifying this bit of bone found in a rockpool in Kimmeridge by 7 year old Annie:

mystery325a

It’s not the easiest item to identify for a variety of reasons. First of all it’s broken, only showing one end and probably missing quite a lot of the element. Next, the images don’t show all of the angles you might want to see and because the object is small the images aren’t as clear as you might like.

However, there are a few angles visible (see below) and there is a scale, so the main requirements to get an approximate identification are in place. I say approximate, because with something like this I think you really need the object in your hand where you can compare it to other material in detail if you want to make a confident identification.

Excuses aside, let’s take a look and see what it might be…

The first thing to note is that the bone is hollow with thin walls. This rules out fish, reptiles, amphibians and mammals (including humans jennifermacaire) – leaving birds.

Weathered mammal bones may have a void in the bone where the marrow would have been, but the cortex (outside layer) will be thicker and near the articular surface it tends to be quite solid.

Hollow bone = bird (usually)

Next, the articular surface of the bone is concave, which palfreyman1414 picked up on:

As far as I recall (mentally running through images in my head) both ends of the proximal limb bones in tetrapods have convex ends?

This is accurate, but while the proximal (near end) of the limb bones are convex, the more distal (far end) limb bones tend to have concave ends, so that helps narrow down what this bony element might be.

Concave articulation

For me the give-away here is the fact that there’s no ridge within the concavity of the articular surface, which means that it will allow movement in several directions – something that the bones of bird feet don’t really need, which is why bird lower legs, feet and toes have a raised ridge inside the articular surface that corresponds with a groove in the other surface, keeping the articulation of the joint tightly constrained.

Articulation of Shag phalanx showing raised ridge

However, bird wing need to make a wider range of motion (at least in some species), so the mystery object is most likely the distal end of a bird radius (the ulna tends to have a hook at the distal end). This is the conclusion that Wouter van Gestel and DrewM also came to (joe vans should’ve stuck to his guns).

Distal articulation if duck radius

Identifying the species of bird is a lot more complicated. The size suggests a pretty big bird, which narrows it down and the locality in which it was found makes some species more likely than others. I took a look at the radius of some species that are commonly found on the coast, like Guillemot, Herring Gull, Duck, Cormorant/Shag and Gannet, Skimmer, Pigeon and I also checked out Chicken, since their bones are probably the most commonly occurring on the planet.

Gannet radius with some distinctive structure around the articulation

Many of the species I checked had quite a distinctive structure around the distal radius articulation, but the gulls, ducks and chickens that I looked at had fairly unremarkable distal radius articulations, making it hard to definitively decide what the mystery object is based on the images.

Herring Gull radius

Chicken radius

So with that somewhat disappointing conclusion I admit partial defeat, but I can say that it’s not from a Cormorant, Shag, Gannet, Pigeon or Guillemot. Sorry I can’t be more specific Annie!

Unfortunately that’s just how the identification game works sometimes… we’ll try again with something new next week!

Friday mystery object #325

This week I have a genuine mystery object for you passed on from my NatSCA colleague Holly, that was found in a rockpool in Kimmeridge by 7 year old Annie when she was out fossil hunting on the beach:

mystery325a mystery325b mystery325c

Any idea what this object could possibly be?

I don’t think there’s any need for cryptic clues this time, as it’s a proper challenge and I’d love to hear what you think it is and what it’s from. Have fun!

Friday mystery object #322

I’ve not had an unusual mystery object for a while, so lets see how this one works out:

Any idea what this identification of this recent acquisition might be?

As always you can leave your thoughts, questions and suggestions in the comments box below. Have fun!

Friday mystery object #320 answer

Happy New Year everyone!

Last week I gave you this skull to identify from the collections of the Dead Zoo in Dublin :

King Vulture Sarcoramphus papa (Linnaeus, 1758)

I also included the label, since it offers an interesting taxonomic twist.

If there’s one principle that I hope I’ve managed to convey over the last eight and half years of doing the Friday mystery object, is that you should never fully trust the label.

For starters, the number NMINH:2006.12.1698 could be misleading, as it reflects the year the specimen was catalogued rather than the year it was acquired. To explain, the NMI uses a very sensible numbering system that starts with the collection (NMINH = National Museum of Ireland Natural History) the year of registration (usually the year of acquisition) which allows you to know which register to look in, followed by the lot number (a sequential number reflecting how many acquisitions have come in that year), followed by the individual object number (the sequential number of that individual item in a particular lot). This system can have additional numbers added if necessary, such as if a piece of an individual object is removed for sampling.

However, some older objects were not registered when they entered the collection and as such they get a number that reflects the year they were documented rather than the year they were acquired. In this case the specimen was registered in 2006, but purchased from an auction of the collections of van Lidth de Jeude who died in 1863, as Nigel (the Dead Zoo Keeper) helpfully pointed out in the comments.

If the specimen had been accessioned and numbered on entering the collection back in the 1860’s then issues with the name would be expected since taxonomy constantly changes and old names are often wrong, but because of the new label and the 2006 date, you’d generally expect the name to be more up-to-date. However, it appears that the information on an old label was directly transcribed without being updated.

This is relevant because the name Orogyps auricularis is what we call a junior synonym, which means it has been used to describe a species that already has an older valid name. When this happens the older name takes precedence. In this case, Orogyps auricularis is a name applied in 1867 by Degland and Gerbe to a species that had already been named Vultur tracheliotos by J.R. Forster in 1796 and which is now placed in a different genus, giving the name Torgos tracheliotos (Forster, 1796) – where the parentheses around the author name indicate that the scientific name has changed from the original version that was published by Forster.

These taxonomic and documentation twists are however rendered redundant as soon as you realise that this specimen is from a totally different species. In fact it’s not really anything like Torgos tracheliotos the Lappet-faced Vulture:

Lappet-faced vulture

In fact, the only real similarity lies in the tip of the beak, which is a functional feature for tearing meat and which is convergent between the Old World Vultures and the New World Vultures. The Lappet-faced Vulture is an African species, while the mystery object has the distinctive deflection of the bill in the nasal region that indicates it’s a species from the Americas. This discrepancy in region was noted by palfreyman1414 and Gerard van den Brink.

Once you focus on the New World Vultures it becomes quite easy to make an identification, since there are only seven species and at 121mm this specimen is the third largest species after the condors – something easy to check on Skullsite. So well done to everyone who recognised the skull as belonging to the King Vulture Sarcoramphus papa (Linnaeus, 1758), especially palfreyman1414 who got there first.

514px-sarcoramphus_papa_-national_zoo_-washington_-usa-8a

King Vulture by Eric Kilby, 2008

As you can see, not only was the taxonomy very out of date for this specimen, it was also completely wrong, because it was misidentified 150 years ago. This is why you should never fully trust labels – they will often be wrong and if you base research on misidentified specimens, that will be wrong too.

Another mystery specimen next week!

Friday mystery object #320

I hope everyone had a lovely Christmas break!

This week I have another specimen from the Dead Zoo to identify – this one has an identification already, but the taxonomy is rather archaic and I think that once you’ve investigated the modern version of the name, you’ll realise that it’s wrong.

Skull length = 121mm

So, any idea what this name should actually be and, more importantly, what the identification actually is?

As always, you can put your thoughts, questions and suggestions in the comments box below – have fun!

Zygoma

Adventures in natural history collections

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