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 #402

This week I have another specimen from the Dead Zoo for you to have a go at identifying:

Skull length approx. 170mm

It’s one of almost two thousand birds that will be put into storage as part of the big decant we’ve been working on.

If you’re interested in finding out more about the project and some of the complexities involved, I’ll be doing a virtual talk about it next Friday evening (GMT) for PubSci – it’s free and the details are here if you’d like to join in.

Have fun!

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 #399

Friday has rolled around again, with startling alacrity.

At the Dead Zoo it’s been another busy week of decanting, with our whale skull being crated up and ready to roll:

All the decant work plus post-Christmas catching-up activity hasn’t left me much time to hunt down mystery objects, but I had this cutie in my office and I thought it might be a nice little challenge:

Any idea what it might be?

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

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!