Friday mystery object #329 answer

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

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I expected most of the regulars to recognise that it’s a bird sternum, since I’ve talked about them quite a lot in the past – to the point of putting together images of a range of sterna from different bird families to help narrow down identifications:

However, this mystery sternum didn’t appear in my gallery, so I thought it would offer a bit of a challenge. Of course, that was before Wouter van Gestel (creator of the fantastic Skullsite resource) recognised it as being from a bird with a fascinating reproductive method based around carefully planned neglect. Yep, this is the sternum of a Common Cuckoo Cuculus canorus Linnaeus, 1758.

Cuckoos are visitors to Britain and Ireland, where they spend their summer holidays destroying the families of host birds (like Dunnocks and Reed Warblers) by removing an egg from the nests of a smaller species and laying their own egg. If the switch isn’t noticed (and most of the time it isn’t) the egg hatches and the Cuckoo chick turfs out the remaining eggs of the host birds, then demands vast quantities of food from the unwitting foster parents.

To help pull off this remarkable feat of irresponsible parenting (or brood parasitism as it’s more properly known), Cuckoos have become remarkable mimics. The male is similar in pattern, colour and flight style to a Eurasian Sparrowhawk – a notable predator of small songbirds.

Common cuckoo by Vogelartinfo, 2010

Common cuckoo in flight. Image by Vogelartinfo, 2010

He hangs around, scaring the host birds off their nest or acting as a distraction, so the female can sneak in and drop off an egg, which itself mimics the colouration of the host bird’s eggs. Different Cuckoos have different species of host bird that they specialise in parasitising, so their eggs are adapted to colour match those host eggs – which is important, since several host species have become wise to the Cuckoo’s tricks and will abandon or destroy any egg they recognise as different.

Reed Warbler nest with what looks like a sneaky impostor egg... Image by NottsExMiner, 2012

Reed Warbler nest with what looks like a sneaky impostor egg… Image by NottsExMiner, 2012

Bizarrely, after all this careful disguise and the danger of discovery, the Cuckoo chick that ends up being fed copious amounts of food by the foster parents rapidly becomes a behemoth that could by no means pass as the same species as its hosts, yet the foster parents carry on feeding it.

Reed Warbler feeding a Common Cuckoo chick in a nest. By Per Harald Olsen.

Reed Warbler feeding a Common Cuckoo chick in a nest. Image by Per Harald Olsen.

It’s remarkable to consider that the complex behaviours of Cuckoos must be entirely genetically determined, since they never meet their parents and never get to learn how to Cuckoo from another member of their own species.

With this as the mystery object, I was delighted last weekend when I heard my first Cuckoo of the year in County Clare – and I was even more excited when I saw one in flight. They may be sneaky destroyers of families, but they are also the heralds of summer in the countryside and it’s hard to not have a soft spot for their evocative call.

Belated Friday mystery object #328 answer

The other Friday I gave you this specimen to have a go at identifying, but alas when the time came to write an answer I was at the Natural Sciences Collections Association (normally just called NatSCA) conference (which has been referred to as “the highlight of the natural history curator’s year”) and as a result I didn’t get much of a chance to write an answer or even read the comments.

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Now I’m back, buoyed up by the fantastic shared experience of the conference (take a look at the #NatSCA2018 hashtag to get an idea of what was going on) and I’ve finally have a chance to look at the specimen, read the comments and write an answer. I was delighted to find some great cryptic poetry, prose and comments – some requiring perhaps a little more intellectual prowess than I’m capable of commanding, especially after an intense few days of conferencing (sorry salliereynolds!)

This specimen has a somewhat thrush-like appearance, but the hooked tip of the bill doesn’t quite sit right for a member of the Turdidae (the family of true thrushes). This somewhat raptorial feature of the beak is seen more in birds like the Laniidae (shrikes) and some of the Saxicolinae (chats). It’s the chats that I’m interested in with regard to this specimen, although not the “typical” chats. The ones I’m interested in have been moved around taxonomically a fair bit.

A lot of birds with a thrush-like general appearance will have been called a “something-thrush” by Europeans and will have kept that in their common name even after taxonomy has moved on and that species has been moved out of the Turdidae. In the Saxicolinae there are a lot of birds that were once considered thrushes and one genus in particular tends towards being a fairly dark colour with blue elements – Myophonus or the whistling-thrushes.

The distribution of glossy blue feathers on members of Myophonus is variable and reasonably distinctive. Also, because these glossy feather colours are structural, they don’t tend to fade in old museum specimens like the colour from pigments. In this specimen the blue patch is fairly dull and confined to the shoulder (or epaulet) and the rest of the plumage is even more dull – possibly faded, but also possibly because it’s female (we all know that it’s usually the boys that are show-offs).

Keeping in mind the distinctive bill, overall size and pattern of colouration, a trawl through the epic Del Hoyo, et al. Handbook of the Birds of the World -Volume 10 yielded one description that fit rather well – that of the female Javan Whistling-thrush Myophonus glaucinus (Temminck, 1823).

These forest dwelling birds live in, you guessed it, Java. They feed on various invertebrates and frogs, a slightly ramped-up diet from thrushes, necessitating a hooked bill tip to keep the more jumpy morsels from getting away.

More mysteries to come this Friday!

 

Friday mystery object #327 answer

Last week I gave you this mystery bone to identify:

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As I suspected, it was simultaneously easy and difficult: easy because it’s clearly an os penis or baculum; difficult because it can be hard to narrow down the species to which a baculum belongs without having specimens for comparison. For some reason people can be funny about penis bones and, despite the fact that male animals tend to be over-represented in museums, the baculum will often have been removed or not included in skeletal mounts.

That said, Steph came closest, getting the right family with the clue:

Bac to the bear-minimum I would guess?

If you remember one of my past posts I showed an image of the baculum mounted on the skeleton of a Giant Panda in Berlin (more about this below):

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You can see that, although it differs slightly with a bit of a dip towards the tip, it’s rather similar in structure to the mystery object.

Oddly however, it appears that this baculum on the Berlin Panda specimen has been switched for that of a different bear species. Pandas have a very distinctive reduced baculum with wings (see below), that looks nothing like this, which is more similar to the os penis of a Spectacled Bear (or possibly a Polar Bear at a push).

The mystery object is actually the baculum of a Sloth Bear Melursus ursinus (Shaw, 1791).

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N.B. note that the writer of this label couldn’t quite bring themselves to write the full word “penis”

In future, should you ever find yourself with an unidentified bear penis on your hands, I suggest taking a look at this handy figure by Abella et al. 2013¹:

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Baculum in laterial view of: A Helarctos malayanus; B Ursus thibetanus; C Tremarctos ornatus; D Ursus americanus; E Melursus ursinus; F Ursus arctos; G Ursus maritimus; H Indarctos arctoides; I Ventral view of the Baculum of Ailuropoda melanoleuca; J Dorsal view of the baculum of Ailuropoda melanoleuca.

So in answering one mystery object we’ve uncovered a far bigger mystery – how did the Berlin Panda end up with the wrong penis?

 

¹Abella J, Valenciano A, Pérez-Ramos A, Montoya P, Morales J (2013) On the Socio-Sexual Behaviour of the Extinct Ursid Indarctos arctoides: An Approach Based on Its Baculum Size and Morphology. PLoS ONE 8(9): e73711. https://doi.org/10.1371/journal.pone.0073711

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:

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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.

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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.

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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.

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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).

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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.

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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.

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Herring Gull radius

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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 #322 answer

Last week I gave you this new acquisition for the Dead Zoo to identify:

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It’s a detail of something large, and it had a lot of you stumped because it looks like a cross between a marble worktop and pork terrine.

However, if you look closely at the bottom left of the image, you may just be able to make out the shape of a sucker-covered arm, because this – as spotted by palfreyman1414 and jennifermacaire – is a big cephalopod.

When I say big, I mean it’s the second largest species after the Colossal Squid (that I’ve talked about before) – that’s right, it’s a view of part of a large ice cube containing a Giant Squid Architeuthis dux Steenstrup, 1857.

Squid holding sailor by Alphonse de Neuville & Édouard Riou, from Hetzel edition of 20000 Leagues Under the Sea, p. 400.

Squid holding sailor by Alphonse de Neuville & Édouard Riou, from Hetzel edition of 20000 Leagues Under the Sea, p. 400.

This individual isn’t actually particularly giant, measuring in at a meagre 5.8m, including its long thin feeding tentacles – quite big, but hardly Kraken-esque. It was caught 118 miles off the Kerry coast after it found its way into shallower waters than the abyssal depths they normally inhabit. You can see details of how it was caught and a photo of the specimen on the Irish Times website.

I haven’t started the process of preserving for the long term yet, as it will require a bit of time to release the kraken from the ice, a large tank and some nasty chemicals – namely a 10% formalin solution and various strengths of Industrial Methylated Spirits (IMS – which is adulterated alcohol), stepping up to 70% in 10-20% increments. I may also need include an alkali buffer in the tank (marble chips are commonly used) since Giant Squid use ammonium chloride in their tissues to increase their buoyancy and that can acidify the solution, leading to accelerated bleaching of the tissues and long-term damage to the specimen.

Even with good preservation it’s unlikely to ever go on display as a full specimen. I can probably find a big enough jar, but the specimen has been dissected and isn’t really looking its best. However, it may be worth showing some of the elements, like an eye, the beak or maybe an arm or tentacle. These may be in good enough condition to use on display to explain some of the interesting features of these denizens of the deep. The rest of the squid will be there for researchers interested in these large, but elusive, molluscs.

Friday mystery object #315 answer

Last week I gave you this big bug to identify:

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I had a feeling it would be fairly straightforward for some of you, since insects as big as this are reasonably distinctive, and I was therefore not disappointed with the flurry of correct identifications.

The first with a correct identification in the comments was Chris, who hinted at the scientific name with this suggestion:

Trying to identify this Cic-sac? Tho phar, Tho good! (Excuth the lithp!)

On social media people made suggestions relating to the common name for the species, mostly pointing out that it’s very loud. Putting the various hints together gives you the Double-drummer Cicada Thopha saccata (Fabricius, 1803).

Cicadas are weird. They’re in the Order Hemiptera (the true bugs) and the Suborder Homoptera (although that’s disputed and it’s probably safer to say Auchenorrhyncha). Best known for being noisy and having some species with synchronised emergence times that vary between every year and up to every 17 years, or somewhere in-between depending on species and environment. They have widely spaced eyes and a blunt head that is pretty distinctive.

As jennifermacaire pointed out regarding cicadas:

According to Plato, “[This species] used to be human beings who lived before the birth of the Muses. When the Muses were born and song was created for the first time, some of the people of that time were so overwhelmed with the pleasure of singing that they forgot to eat or drink; so they died without even realizing it. It is from them that the race of the [these insects] came into being; and, as a gift from the Muses, they have no need of nourishment once they are born. Instead, they immediately burst into song, without food or drink, until it is time for them to die. After they die, they go to the Muses and tell each one of them which mortals have honored her.”
– Phaedrus

The implications of this is that adult cicadas have a general inability to feed, although this isn’t quite true, since adult cicadas may still feed on sap.

This particular cicada is Australian and is one of the loudest insects on the planet, able to produce a call of over 120 decibels – loud enough to cause permanent hearing damage if right up against a human ear.

The abdomen is fairly hollow in the males of these insects, creating a resonating chamber, but sadly the last segment of this specimen has fallen off, making it hard to be sure of the gender on the basis of the genitals. However, the males have a couple of resonating sacs behind the hind-wing that is missing from this specimen, suggesting that it’s a female.

As far as noisy neighbours go, these insects are an occasional disruption, popping up every 4-6 years and making a noise that is apparently similar to high-pitched bagpipes.

It doesn’t sound great to me, so I’m (not so) secretly glad that I only have to deal with dead examples of these fascinating insects.

More mystery object fun next week!

Friday mystery object #310 answer

Last week I thought it was time for some more bones, so I gave you this specimen from the Dead Zoo to have a go at identifying:

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There was no scale, the photo is far from ideal and the specimen isn’t in the best condition, but the animal is pretty distinctive, so I thought it wouldn’t prove too much of a challenge – and it turns out that I was right.

Palfreyman1414 was the first to identify it to genus level, correctly recognising that it was one of the two Notoryctes species of Marsupial Mole from Australia.

The weird limbs are a pretty good indicator this being a digger, with large muscle attachments and robust forelimbs, but it has couple of large claws rather than the ridiculous giant hands of the Old World Moles and it has a shorter skull.

Double prep mole from the Horniman Museum

Double prep of an Old World Mole Talpa europaea from the Horniman Museum & Gardens

The skull is more similar to that of the golden moles of southern Africa, although their rostrum (nosey bits) tends to be more concave while the marsupial moles have a more convex rostrum (and in some cases, weirdly flaring zygomatic arches).

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Lateral view of the skull of a Giant Golden Mole Chrysospalax trevelyani from the Grant Museum of Zoology

Now distinguishing between the two species of Marsupial Mole is a bit more tricky, not least because they are quite poorly known animals and there aren’t many specimens available for comparison – this is particularly true of the Northern species, which was first described as recently as 1920.

This is actually quite useful to know, since the mystery specimen came into the collection in 1897 – from Southern Australia – so it’s safe to say it’s the Southern Marsupial Mole Notoryctes typhlops (Stirling, 1889), but that’s not very helpful from a morphological perspective.

So far I’ve not found any useful skeletal features that help differentiate the two species, but apparently their fur colour is a little different, with the Northern species having pinkish or cinnamon fur and the Southern species having yellowish-white to a deep gold. To see what they look like with their fur, here’s the taxidermy partner to the mystery skeleton:

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Taxidermy Southern Marsupial Mole Notoryctes typhlops in the National Museum of Ireland – Natural History

As with most moles these subterranean critters have adapted to spending much of their time underground by losing their eyes, investing in some serious digging equipment and tuning in to smells and low frequency sounds.

I hope you enjoyed this little tour around the main moles of the world! More mysteries next week.