Friday mystery object #405 answer

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

There was no scale and admittedly there’s not much of the specimen visible, but I didn’t think that would pose much of a problem. And I was right. Tony Irwin immediately indicated the identity of this rather rare specimen with the anagram:

Maybe found it – in rosy pea?

The “in rosy pea” unscrambles to Aepyornis which is the generic name for the Elephant Bird.

Of course, this isn’t a complete Elephant Bird, it’s only an egg (had to get some Eastery link in there somehow). Elephant Birds have been extinct for about 1,000 years, so surviving eggs are very rare, hence the special fancy box. Here’s the actual egg:

The total length is just shy of 1 foot at 29.6cm, making this one of the largest eggs ever laid by any animal. There are other Elephant Bird eggs that are a bit bigger (up to 34cm), but no other type of animal ever laid a bigger egg, even the vast sauropod dinosaurs laid eggs that were smaller than this.

I’m not going to tell the story of this specimen here, since it’s already on the National Museum of Ireland’s website. If you have a read of that, you’ll see that this specimen is from the southern end of Madagascar (the island on which these birds lived) and that plus the particularly large egg size suggests that this is from Aepyornis maximus I. Geoffroy Saint-Hilaire 1851.

This is not the first time I’ve dealt with Elephant Bird eggs, since I borrowed one from David Attenborough for an exhibition at the Horniman Museum about 5 years ago, which I talked about here.They are remarkable objects and it’s strange to think of something as fragile and seemingly ephemeral as an egg surviving intact for over a thousand years.

So well done to everyone who worked out what this mystery was – eggcelent work!

Friday mystery object #404 answer

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

It wasn’t really much of a challenge for the usual suspects, with everyone recognising this as a Common Hill Myna Gracula religiosa Linnaeus, 1758.

However, my reason for picking this as a mystery object wasn’t for the challenge offered, but as an illustration of just how frustrating the taxonomy of old collections can be. Everyone recognised this bird, which is not a huge surprise, given how familiar this species has become due to the pet trade, but anyone looking at this specimen on display would probably struggle to match the specimen to the species considering the label that was attached:

The common name here suggests that the specimen is from Malaysia, then the scientific name suggests Java, but then the locality associated is just “East Indies”. The genus name does at least bear a passing relationship to the modern specific name (“Eulabes” means “pious” or “devout” while “religiosa” is self-explanatory). Similarly “Grackle” does hold a clue to the modern Genus name of “Graculus“. Most confusing.

To make things worse, the Graculus is now recognised as forming a species complex across Asia, so it would be good to narrow down which subspecies this specimen belongs to:

Distribution of the various species and subspecies within the genus Gracula. Image by L. Shyamal, 2009

The pattern of coloured feathers on the neck and head on the Dead Zoo specimen appears to match G. religiosa intermedia most closely, so when I eventually reach the stage of rewriting labels for specimens on display, I’ll do my best to improve the information. Unfortunately, this will probably need to happen for around 75-80% of the collection, so no pressure…

Friday mystery object #403 answer

Last week I gave you this rather beautiful mystery object from my old place of work, the Horniman Museum:

It’s the only example I’ve seen of this species that’s been prepared to show it from this perspective – and it’s pretty special. There were plenty of answers, with most people on the button with the what it’s from.

Goatlips was the first to jump in with the broader identification, but palfreyman1414 was first to get the the species. The highly reflective, pearly surface (comprised of mother-of-pearl or nacre) provides a bit of a clue. This is a transverse section of a Pearly or Chambered Nautilius Nautilus pompilius Linnaeus, 1758.

Normally when people take sections through a Nautilus they take a sagittal section, to show the near perfect logarithmic spiral formed by the shell as it grows, so the transverse section offers a perspective that’s much less familiar:

Image of Nautilus shell in sagittal section taken by Chris 73, 2004

Since the transverse section is so unusal it’s quite difficult to find good references for identification. However, with a good imagination you can work out what’s going on with the relative sizes of the chambers and how much they overlap, to get a sense of the shape in the coronal plane (that’s the line through the body that gives us a transverse section).

That said, it’s easy to recognise that this shell is from the genus Nautilus rather than Allonautilus thanks to this image from Jereb and Roper, 2005:

Shell characters of genus Nautilus vs. genus Allonautilus. After Jereb and Roper (2005), modified by Antonov, 2008

There is also a paper by Ward and Sanders, 1997 with the same sections shown, plus an additional illustration of N. macromphalus which lacks the thick side walls seen in N. pompilius. From what I’ve seen I’m reasonably happy that the specimen is a Pearly Nautilus, but the taxonomy of this ancient group of cephalopods is still quite poorly known, so I’ll hang on to a shred of doubt for a while.

Friday mystery object #402 answer

Last week I gave you this awesome skull to have a go at identifying:

Skull length approx. 170mm

Of course, you’d only recognise this as being awesome if you knew what it’s from, since apart from bit of a weird shape to the top of the skull, it looks like it could be from a chunky galliform or perhaps a Screamer. However, this skull is from a type of pigeon.

Of course, it’s not from one of your boring standard sorts of pigeon, this skull is from a very special pigeon. Adam Yates pipped everyone to the post in the comments, identifying that this is the skull of a Rodrigues Solitaire Pezophaps solitaria (Gmelin, 1789).

If you’re not familiar with the Solitaire, it’s the closest known relative of the Dodo and, like its cousin, it was large, flightless and it’s now extinct. The similarity doesn’t stop there, as both were endemic to a small, unpopulated island in the Indian Ocean, hundreds of miles east of Madagascar and both were driven to extinction not long after humans first visited the island and dropped off goats, pigs and (inadvertantly) rats.

The closest living relative of both of these extinct birds is the Nicobar Pigeon, found in a string of islands in the Bay of Bengal. While the Nicobar Pigeon is colourful with iridescent feathers that shift colour in changing light, the Solitaire was reported to be a a grey and brown bird about the size of a swan.

The colourful Nicobar Pigeon

A handful of reports are the only real source of information about the plumage and general appearance of a live Rodrigues Solitatire, with just one illustration ever being made by someone who has seen the bird. That was François Leguat, a French naturalist who arrived in Rodrigues in 1691. His artistic skills were more stylistic than descriptive, but he did describe the Solitatire’s plumage as beautiful.

Le Solitaire by François Leguat, 1708

Fortunately, we know a lot more about the bones of Solitaires than we do their plumage, thanks to large fossil deposits of the bird uncovered during the Transit of Venus observations from Rodrigues in 1874. The Dead Zoo specimen is a composite skeleton made up of bones brought back from that expedition and presented to the Museum on behalf of the Royal Society.

My favourite bit of the skeleton is probably the fighting knobs on their wrist bones. They’re a little hard to see here, but apparently the Solitatire’s could be quite aggressive and attack with their wings, which had presumably become repurposed for competition (and perhaps defense) since they were no longer needed for flight:

There will be more mysteries next week, but before you go I wanted to drop in a reminder that I’ll be doing a talk about Dismantling the Dead Zoo this evening at 7pm GMT. If you’re interested in finding out more about how to take apart whales and wrangle hippo heads, why not sign up and join in for free?

Friday mystery object #401 answer

Last week I gave you this gnarly looking skull from the Dead Zoo to identify:

I didn’t think it would be a difficult one, especially since it is a critter I’ve used as a mystery object before (although that was over 10 years ago!)

As I suspected, everyone figured out that this is the skull of an Alligator Snapping Turtle, but things have become a bit more complicated than they used to be over the last decade, since the single species that used to be in the genus Macrochelys has since been split.

The amount of splitting has varied, but at the moment it seems to have settled on two species being recognised; Macrochelys temminckii (Troost, 1835) and Macrochelys suwanniensis Thomas et al., 2014.

Variation of the squamosal in A. Macrochelys temminckii and C. Macrochelys suwanniensis. Adapted from Thomas et al. 2014. Zootaxa 3786(2):141–165

One of the key diagnostic features identified to differentiate between them is the angle of the squamosal (the bit of bone with the arrow pointing it above). In M. temminckii the angle is greater than 90° whereas in M. suwanniensis it’s less than 90°.

That suggests to me that the Dead Zoo specimen is probably the Suwannee Snapping Turtle Macrochelys suwanniensis Thomas et al., 2014. The only problem with this identification is that the collection locality is simply “Mississippi”, which doesn’t fit with the Suwannee river distribution of the species.

I’ll need to go back and look at a few other skeletal characters to confirm the identification once I’m back in the Dead Zoo, but my guess is simply that the collection locality wasn’t accurately recorded, since the specimen came from the natural history supplier Edward Gerrard rather being collected and properly documented by a researcher.

It certainly wouldn’t be the first time a representative locality has been given for a specimen meant for display or teaching rather than research!

Friday mystery object #400 answer

Last week we hit the 400th mystery object, which was this specimen from the Dead Zoo:

Horned beasties can be tricky since there are over 140 species in the Bovidae. There is quite a lot of diversity in size and in horn shape, but there are some general patterns, with spirals, twists, curves and recurves. A good place to trawl through for comparisons is the Animal Diversity Web, which has plenty of images.

However, this is one of the better known species, with nicely lyrate horns, so quite a few people recognised it without having to go searching. This is a Springbok Antidorcas marsupialis (Zimmermann, 1780), a South African antelope that has given its name to the nation’s rugby team. Well done to everyone who figured it out, particularly Goatlips, who got there first!

This specimen is one of 333 game heads that we’re in the process of decanting from the Museum, as part of a project that includes moving thousands of invertebrates and birds, as well as a couple of whales. If you’re interested in how we’re dealing with the game heads we recently reported on it at the NatSCA Conservation Twitter conference, which I’ve shared below:

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Friday mystery object #399 answer

Last week I gave you this cute little bird of prey to have a go at identifying:

It didn’t prove to be much of a challenge, but I was impressed by the answers nonetheless. In particular, the first answer by Hilary Blagbrough is both a delightful poem and correct:

A little hunter from the east
that feasts on juicy dragonflies
In black and white is smartly dressed
No colours seen on legs or chest
Who is this with the panda eyes?
That of its sort, is not the least

So this mystery object is a bird of prey found in Asia. It’s very small and primarily feeds on insects, although it can take small mammals, reptiles and other birds of a similar size or smaller than itself. Since it’s a falcon, but smaller than expected, it’s called a falconet.

There are a few species of these falconets that are quite similar. However, as Hilary says, this one doesn’t have any colours on the legs or chest and it’s just black and white, without any patches of colour and it has discrete patches of black around the eyes. These features all suggest that this is the Pied Falconet Microhierax melanoleucos (Blyth, 1843).

There were several correct identifications on Twitter and more in the comments on the blog after Hilary’s poetic post. So well done to everyone who figured it out!

Friday mystery object #398 answer

Happy 2021 – I hope you had a great celebration!

Last year I gave you this mystery skeleton for you to have a go at identifying:

That erect stance and those super-short and chonky wing bones are a dead giveaway that this is one of those charismatic flightless waiter birds (and before you ask, yes the “i” is intentional).

There are around 20(ish) species of penguins or pengwings if you’re Benedict Cumberbatch.

Although the various species look superficially similar, with their black and white base colour scheme and tubby yet streamlined shape, they do have some distinguishing characteristics. Unfortunately, the most obvious relate to plumage and that’s missing here.

Size can help with narrowing it down – and this particular specimen is small. Admitedly it’s hard to tell that without a scale bar, but the large species have relatively small skulls in proportion to their body size, so they can be ruled out.

Bill length and shape can also provide some good indications even from non-skeletal birds and you can of course check out my favourite online resource (SkullSite.com) to see skulls of most of the main penguin genera, if not all the species (yet!). In the comments, James Bryant and Wouter van Gestel (creator of the aforementioned SkullSite) recognised that this is a Little, Blue or Fairy Penguin Eudyptula minor (J.R.Forster, 1781).

Little Penguin in the Melbourne Zoo. Image by fir0002, 2009.

This is the smallest species of penguin, it has breeding colonies in Australia and New Zealand and the population on Phillip Island has become a bit of a tourist attraction. They feed on small fish, like anchovies and pilchards or small invertebrates including squid and jellyfish.

There will be more mystery objects to come for 2021 – let’s hope this year works out better for everyone than 2020…

Friday mystery object #397 answer

I’m going to start this week’s blog mystery object with an apology – it’s going to be a short one, as I’m in the final throes of taking down our Fin whale, which means I’m exhausted after several long weeks of hard graft. Check out the #DeadZooDiary hashtag on Twitter if you want to get an idea of what’s involved.

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

It wasn’t too difficult to narrow it down to one of a few species, thanks to the very distinctive knee region.

There are only a small number of birds that have adopted this extreme elongation of the cnemial crest on their tibiotarsus and patela. These are all specialist foot-propelled swimmers that need that long lever to help power their diving strokes. This is a feature limited to just the grebes and the loons/divers.

Most people figured out that this is the skeleton of one of the loons. The skull provides some clues, but unfortunately the angle of the photo doesn’t make it easy to figure out which of the five species it is.

The scale does rule out the larger of the species (Gavia immer or G. pacifica), but there are three other possibilities. For me the postorbital region suggests that this is the Arctic Loon Gavia arctica (Linnaeus, 1758), which fortunately matches the label.

I hope you enjoyed this weird kneed bird – congratulations to Goatlips and everyone else who figured it out!

Friday mystery object #396 answer

Last week I gave you this bumpy little critter to identify:

I think everyone recognised the mystery object as some kind of Nudibranchia or sea slug. The general type of sea slug is identifiable by that ring of gill filaments known as a branchial plume that you can see at the top of the specimen. This is characteristic of the suborder Euctenidiacea, also known as the dorids.

I called it bumpy, but if you look closely you’ll see that the bumps are pinched at the base and actually look rather warty. There’s a clue in that – and several of you spotted it.

There were a number of wart-related nudibranch suggestions that were close, but jennifermacaire was spot on with her comment:
Doris has warts?

This is indeed a Warty Dorid or Doris verrucosa Linnaeus, 1758.

Warty dorid, image by AndyT

This specimen isn’t quite as faded as everyone expected – they’re usually a fairly muted orange, yellow or a greenish colour, not too different to the mystery object. This probably serves as camouflage against the background of the Warty Dorid’s favourite food, the Crumb-of-bread Sponge, which also varies in colour from bright yellow to darker shades depending on the depth of the water in which they live.

More mystery objects next week!

Friday mystery object #395 answer

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

There were some great suggestions, some alluding to the tusk-like shape and structure, but the first person with a correct identification was Tony Irwin with an anagram of “Kuphus“. If you’re not familiar with the Giant Shipworm Kuphus polythalamius (Linnaeus, 1758), it’s a genus of boring mollusc that has proved to be rather interesting.

It’s in the shipworm family, but until recently it was only known to science from large, empty tubes like this one that washed up on a few beaches in the Philippines. That all changed 2016 when some live specimens were found and researchers were able to take a closer look at the biology of these surprising animals.

Unlike other shipworm, it turns out that Kuphus doesn’t eat wood. Instead it burrows into sediment and has a symbiotic relationship with bacteria that live in its gills, which metabolise hydrogen sulphide. This is quite a big deal, since it seems to provide an example of one set of symbionts (those able to digest cellulose in other shipworms) being replaced by a very different set capable of metabolising inorganic chemicals.

This change in relationship allows Kuphus to utilise in a different habitat type and may provide a clue as to how some of the organisms present along mid-ocean ridges have managed to adapt to a habitat far away from sunlight and largely removed from normal organic inputs.

It’s odd to consider that this specimen has been in the Dead Zoo since 1879, but we never knew just how interesting the species is until so recently. I wonder what other revelations we’ll come across as we carry on with our decant?

Friday mystery object #394 answer

Last week I gave you this mystery object to have a go at identifying:

Clearly it’s some kind of sea-star, but there are a LOT of different species .

Remarkably, that doesn’t seem to have posed a problem. The five stumpy arms narrowed it down to one of the cushionstars or biscuitstars and it seems that was more than enough for some of you.

Salliereynolds flagged one of the diagnostic features and dropped a hint to the species name:
“Six lumps to a side? From down under?”

But Goatlips took the mystery object to a whole new level with a biscuit recreation:

This specimen is a Southern Biscuit Star Tosia australis Gray, 1840. Probably not as tasty as an actual biscuit, but certainly very biscuity in appearance.

A short answer today I’m afraid, but it’s been a difficult week and there’s a lot to do in the Dead Zoo this Friday!

Friday mystery object #393 answer

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

It was a bit mean of me to not include a scale, but several of you managed to work it out regardless.

The overall group is fairly easy to spot, since it has 10 legs, the front pair bearing claws (or chela if you want to get technical) and the main body area is rounded. So it’s a crab.

In addition, the long legs and small body give it an overall shape reminiscent of a spider, so it’s a good bet that it’s some kind of spider crab.

Now, there are quite a lot of types of spider crab out there, but that sub-triangular body shape and those long legs help narrow down the possibilities further. In fact, it does share some similarities to the gigantic Japanese Spider Crab.

Japanese Spider Crab specimen at American Museum of Natural History. Image from Popular Science Monthly, June 1920

Unlike the Japanese Spider Crab (which was suggested), this doesn’t have extremely elongated chela. So not one of them. It’s also way too small, although my lack of a scale bar doesn’t make that obvious – sorry! However, the mystery object is in the same family (the Inachidae).

Once you start looking at the genera in the Inachidae there’s only one that matches the mystery object’s proportions, and that’s the Macropodia. Once you get that far, it becomes a case of discounting possibilities based on much more detailed features.

The Marine Species Identification Portal is a fantastic resource for checking this finer level identification. Going through the various species descriptions in there helps spot the key features for distinction between species.

In this case, the mystery object is particularly similar to M. tenuirostris and M. rostrata and it’s mainly the shape of the carapace around the ‘shoulders’ where the chela attach to the body that help confirm this to be the Long-legged Spider Crab Macropodia rostrata (Linnaeus, 1761).

So it was a good effort for everyone who managed to get this to family level, I congratulate those who worked this out to the genus and I doff my hat to anyone who managed to identify it to species. So jennifermacaire, my hat is doffed!

Friday mystery object #391 answer

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

I think it’s quite a distinctive skull, so I didn’t provide a scale and I asked for cryptic clues to avoid spoiling the challenge.

The overall skull shape is fairly standard for an Artiodactyl, but while this specimen has no incisors in the upper jaw, there are fairly obviously empty alveoli that show where the teeth used to be. That means it’s not a member of the Ruminantia (the deer, antelope, cattle, giraffes and weird deery-antelopey type critters like chevrotains) since they all lack upper incisors.

That leaves the pigs, hippos and camels – and it’s clearly not one of the pigs or hippos.

The camel family is a bit odd. There are three wild species, but then an additional four entirely domesticated species. The proportions of this skull are a bit long for a Llama, Guanaco, Alpaca or Vicuña. That leaves the Dromedary, Wild Bactrian or Domesticated Bactrian camel as possibilities.

Dromedary skulls tend to have a horizontal nasal region then a steep rise to the braincase immediately behind the orbits, but this specimen has a more gentle slope running from the nose to the top of the braincase, so it’s Bactrian.

Unfortunately the Wild Bactrian camel is critically endangered and poorly represented in collections, so it’s hard to find enough comparative material to differentiate the wild and domestic Bactrians.

Well done to everyone who figured out that this is one of the double-humped ships of the desert. There were some great clues in the answers!

Friday mystery object #390 answer

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

It came from a cabinet of cave bones, but Nigel Monaghan (Keeper of the Dead Zoo) wasn’t convinced that this specimen was actually found in a cave.

Partly that’s because it’s a fairly fragile specimen with poorly fused sutures – these don’t usually stay connected in cave deposits, but also because it’s from a species that you wouldn’t expect to find in the kind of caves that the rest of these collections came from. So what is the species?

I don’t think this is a very difficult one since I’ve done very similar specimens before (regular visitors should have had an advantage), so I was looking for cryptic or entertaining answers – and I was not disappointed. Tony Irwin got a great clue in, with a pun that reflected the genus:

I think we need to focus (did I spell that right?) on the shape.

It is of course the skull of a seal in the genus Phoca – and the blunt shape of the anterior portion of the auditory bulla suggests to me that it’s a Harbour Seal Phoca vitulina Linnaeus, 1758 rather than the very similar Spotted Seal, which has a slightly more accute angle on the anterior auditory bulla.

So well done to everyone who figured it out! Now we just need to figure out how it either got into a cave or (possibly more likely) got put into the wrong cabinet.

Friday mystery object #389 answer

Last week I have this mystery object from the Dead Zoo:

I made it a bit harder than necessary by not including a scale, but then that’s part of the fun – and I think a scale might have made it all a bit too easy.

There were a lot of suggestions about what it might be, mostly referencing some kind of seat / saddle or a patella. It’s probably just about big enough to sit on, although I’m not sure it would be comfortable.

But quite a few of you did figure out what bone it is and more or less what kind of animal. It’s the manubrium (part of the sternum) of a young Humpback Whale Megaptera novaeangliae Borowski, 1781.

Here’s the specimen with our Conservator Silvia for scale next to the manubrium (it’s a little hidden by the bar supporting the mandible here). Silvia’s been busy cleaning the whale, ready for it to be dismantled in the next few weeks.

All the activity around this whale work has been keeping me busy, so I apologise for tardy replies to questions and slightly sparse answers. If you want to see what we’ve been up to, check out the #DeadZooDiary!

Friday mystery object #386 answer

Last week I gave you this taxidermy bird to have a go at identifying:

wp-1594323862183.jpg

It’s fairly obviously a duck of some sort, but there are almost 150 species in the duck family Anatidae, so that’s not really enough information.

Of course, the ornithologists were up to the challenge of working out which type of duck this was, with Wouter van Gestel dropping hints at a Steamer Duck. If you’re not familiar with Steamer Ducks, they are in the genus Tachyeres, there are only four species and they all live at the southern end of South America.

Of the four species, only one (the smallest) can fly. The others are very large, heavy and flightless. They sometimes use their small wings as a power assist in fast swimming, using a style reminiscent of an steamer ship’s paddles – hence the name.

The small wings on this specimen, as pointed out by Allen Hazen, suggest that this is one of the three flightless species, ruling out the Flying Steamer Duck T. patachonicus as a possible contender.

The three remaining species are all very similar and although some images online suggest that only one species has an orange bill, they all have quite a bright yellow-orange bill following their moult that becomes duller over time. Of course, when dealing with taxidermy you can’t fully trust things like leg or bill colour as they can rapidly fade after death and they are usually painted to give an impression of the natural colour – sometimes with a bit of artistic license.

This particular specimen is identified as Tachyeres cinereus, which is not a valid species, so I was hoping there would be someone with a useful morphological hint to help distinguish between species, but most ways of distinguishing rely on comparisons of bill length, mass and size.

However, this specimen does have a collection locality – the Falklands. There are two species of Steamer Duck that occur on the Falklands and fortunately one of them is the species that flies and has already been ruled out, so it seems likely that this is a Falkland Steamer Duck Tachyeres brachypterus (Latham, 1790).

Pair of Falkland Steamer-ducks. Image by In Vitrio, 2018

So well done to everyone who said it was a Steamer Duck – I think that’s about the best identification possible from the information provided!

On an unrelated note – over the next few weeks my mystery object answers may be a bit on the brief side. Projects at the Dead Zoo are underway that are taking up a lot of my time, so I may struggle to find time for detailed answers. If you’re interested in what I’ll be doing you’ll be able to check out the #DeadZooDiary hashtag on Twitter and Instagram, which we’ll be adding things to starting next week. Exciting things are underway!

Friday mystery object #384 answer

Last week I gave you this unusual looking skull to have a go at identifying:

mystery384

That low and elongated shape, combined with the large number of teeth and absence of a zygomatic arch – all within the context of the relatively large (but still quite small) size – all combine to narrow this down to just a few possible options.

There are a bunch of critters in what used to be called the “Insectivora“, back in the dim and distant days of my undergraduate studies. This wastebasket for things that look like they should be chasing acorns in a cartoon was rightly broken up into more meaningful cladistic groups during the great molecular taxonomic revolution in the dying days of the last century.

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Scrat, a fictional sabre-toothed squirrel that looks like every third member of the old ‘Insectivora’

To be fair, there’s a reason why the “Insectivora” lasted as long as it did and why it took molecular research to finally tease the various groups apart. They don’t have many strong distinguishing anatomical features that are seperate them into clear higher level groupings. Sure, they look a bit different at the family level, but any higher than that and they smoosh into bunch of small toothy critters, many with no cheekbones to speak of.

However, some do have a zygomatic arch, such as the talpid moles and desmans, so it’s not one of them:

mystery330b-e1526623553591

Skull of European mole Talpa europaea Linnaeus, 1758

It also lacks the large orbits of something like a Sengi or Elephant Shrew:

Skull of a North African Sengi Elephantulus rozeti (Duvernoy, 1833).

It also lacks the well-developed sagittal and nuchal crest you’d associate with the Malagasy tenrecs:

Skull of a Tail-less Tenrec Tenrec ecaudatus Lacépède, 1799.

It also lacks the backwards projecting nuchal crest of a solenodon and it’s just too big for one of the true shrews – the largest of which is the Asian House Shrew with a skull length of around 38mm.

So this specimen isn’t as hard to recognise as it could be. The very flat top to the skull with the nostrils up high is a bit of a clue – something often (although not always) associated with aquatic animals. On closer inspection there are two likely suspects – the Web-footed Tenrec or one of the Otter Shrews (which are neither otters nor shrews).

The area around the occipital is a dead give-away here. The Malagasy Web-footed Tenrec Limnogale mergulus (Major, 1896) has an occipital region that’s hard to see in a side view, because the parietals extend down quite low, whereas the Otter Shrews have much higher parietal margin that exposes the occipital region – just like we see in the mystery object.

Finally, the size is give-away. As many of you recognised and hinted at (occasionally with some dodgy puns – I’m looking at you Tony), this is a Giant Otter Shrew Potomogale velox (Du Chaillu, 1860). These semiaquatic relatives of the tenrecs are unusual in how they swim, lacking webbed feet and relying on a laterally flattened tail to swim using a fish-like undulation. So well done to Jane, Tony Irwin, katedmonson, Allen Hazen, Rémi and everyone else who managed to work out this weird mystery.

Friday mystery object #383 answer

Last week I gave you this slightly mean mystery object from the Dead Zoo to have a go at identifying:

wp-1590685198270.jpg

I say it’s mean because it’s just a small fragment from the tip of the lower jaw. It does have some pretty distinctive teeth in it, so it’s probably not the most difficult mystery object I’ve shared, but it’s also from a species in a group of animals that are quite poorly known.

That said, Chris Jarvis was the first to comment and got it right immediately. However, there was a lot of subsequent discussion about how to be sure, given the poor representation of comparative specimens available and the similarities between this species and others in the family. That family is the Ziphiidae, which are the the Beaked Whales.

These cetaceans are rarely seen due to their deep water habits, sometimes diving to depths of nearly 3km (although more usually around 1km) to feed mainly on deepwater squid that they detect using echolocation. Most of what’s known about them comes from strandings – which is where this mystery specimen comes from.

The males tend to be smaller than the females, but the males of most of the 21 Beaked Whale species have tusk-like teeth that they probably use to fight over females, although the behaviour hasn’t been recorded, only deduced from scars and the behaviour of other animals with similar sexually dimorphic characters (there’s an interesting paper on the evolution of the tusks by Dalebout et al. 2008 is you’re interested [pdf]).

The teeth occur in different parts of the jaw and have a different shape depending on the species, so the fact these are located at the tip of the lower jaw means quite a lot of the species can be discounted. If you want to be able to do the narrowing down easily I recommend an old and somewhat unwieldy to navigate, but still very useful online resource – the Marine Species Identification Portal. If you can work out the navigation you can find small line drawings of the skulls of all species in lateral view.

Once you get that far it becomes easier to search for more detailed images of the couple of species it might be, which can yield some great 3D scans to help you work it out. Both Chris Jervis and katedmonson found examples and shared the links in the comments. Here’s a nice one from the NHM, London:

This species (the Cuvier’s Beaked Whale) clearly has bigger tusks than the mystery specimen, which you can see as a scan on the excellent Phenome10K resource*. The mystery object is the distal portion of the mandible of a male True’s Beaked Whale Mesoplodon mirus True, 1913. So well done to Chris Jervis for being the first to get in with the correct identification.

It may seem a bit odd to have just this small portion in the Museum, but as far as records go they represented a managable identifiable voucher for the stranding of the species in Killadoon, Co. Mayo, Ireland back in February 1983. These days we ask for even less material to keep track of strandings – just a small skin sample will do as long as it’s collected and recorded following the guidance of the Irish Whale and Dolphin Group’s (IWDG) Strandings Network.

These samples are stored in alcohol and form the Irish Cetacean Genetic Tissue Bank which is managed in partnership between IWDG and the Dead Zoo to provide genetic data for research into whales. It’s a fantastic resource, but I doubt that anyone could identify the species represented in the samples without access to a genetics lab. And that’s why I like bones best.

*A. Goswami. 2015. Phenome10K: a free online repository for 3-D scans of biological and palaeontological specimens. http://www.phenome10k.org.

Friday mystery object #380 answer

Last week I gave you this specimen from the “Unidentified” drawer in the collections of the Dead Zoo to try identifying:

mystery380

I don’t think anyone had much difficulty in identifying it, since it is quite a familiar and characteristic skull, but well done to everyone who worked out that this is a European Badger Meles meles (Linnaeus, 1758).

There are two other species in the same genus – the Asian Badger M. leucurus and Japanese Badger M. anakuma, so they also need consideration (skulls of all three species can be seen in this paper by Andrey Puzachenko). However, the Japanese Badger is a smaller and more delicately skulled animal and the Asian Badger can be distinguised by differences in the shape of the region around the bony bulbs that hold the ear bones (called the auditory bullae – in Asian Badgers they’re more obtuse and have a straighter lateral margin).

So apart from the distinction between two members of the same genus, this is a fairly straighforward specimen to identify, it makes me wonder why it wasn’t recognised in the collection? I think there are a couple of factors, which I’ll outline here.

The first is that the lower jaw (mandible) is missing. This is totally normal for almost any kind of animal skull you find, except these badgers, which have a well-developed bony process that locks the mandible into the long jaw articulation (known as the glenoid fossa).

Badger

Badger skull with mandible locked in place.

Glenoid

Detail of jaw articulation showing the main features. Red = mandibular articulation, Blue = inside of glenoid fossa, Green = glenoid process that helps lock the lower jaw in place.

This captive mandible is a dead give-away when you see it, but it does mean that when it’s missing it can be confusing.

A mature adult European Badger like this (as indicated by the well-developed sagittal crest) would also normally have extremely extensive wear on their molar teeth, due to the abrasive grit in the gut of their main diet of Earthworms.

Molars

Extensively worn upper molars of an adult European Badger

But the mystery specimen has remarkably little wear on those massive molars. This suggests that it probably had a different diet than is usual for a Badger from northern Europe – and no, not mashed potatoes. The same species in southern Europe has a different diet to their northern counterparts, dominated by insects and fruit, so I wonder if the specimen was collected during someone’s holiday to somewhere in the Mediterranean?

[UPDATE 28th April 2020. Several people have kindly shared images of their badger specimens and it seems that the level of wear in my specimen is not as common as I thought. In one discussion the issue of soil type was raised and I think that may play a big factor. This specimen came from Devon, in an area with sandy soil. Other specimens from areas with muddy or silty soils showed much less wear. This may be coincidence, but it would make sense that Earthworms with coarser soil in their gut would be more abrasive to eat and therefore cause more dental wear. That would be fairly straightforward to test using museum collections. If this hypothesis about wear is correct, then the mystery specimen could be from anywhere with soils that aren’t too sandy.]

I hope you found that useful, or at least a bit of a distraction from lockdown. Stay safe!