Friday mystery object #305

This Friday I’m giving you a game of heads or tails from the Collections Resource Centre of the Dead Zoo:

mystery305amystery305bmystery305cmystery305d

I don’t normally add a photo of the tail, but in this case it should make the identification a doddle – literally a 50:50 shot at getting the right species. If you know what I’m talking about, then please be cryptic in your suggestions – don’t spoil it for everyone else!

If you don’t know why this tail is so significant then you should know that the skull is 10cm long and all will be revealed next Friday!

Good luck!

 

Friday mystery object #304 answer

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

mystery304

The skull of specimen LDUCZ-Z144 from the Grant Museum of Zoology

I thought that some of you would find it a bit easy, but the most diagnostic features aren’t visible in the image and it’s a nice specimen, so I went with it.

There is a bit of similarity with the skull of a ruminant, as noted by palfreyman14141, while Gerard pointed out that it’s from Africa and James M. Bryan was the first to drop a solid clue pointing to the correct species. As jennifermccaire says, it’s the very first on the list (assuming the list is alphabetical) – an Aardvark Orycteropus afer (Pallas, 1766).

An Aardvark at Detroit Zoo by MontageMan, 2008

An Aardvark (or as I prefer to call it, a Tippy-toes McSnuffleface) at Detroit Zoo. Image by MontageMan, 2008

Picking up on palfreyman1414’s observation about it looking like a ruminant, Allen Hazen asked an interesting question about the teeth, because the diet of these bizarre looking animals almost entirely consists of ants and termites, and most other mammals with a similar diet (like Pangolins and Tamanduas) have no teeth at all.

Making the presence of teeth even more weird is the fact that Aardvark stomachs have a muscular pyloric region that grinds up food in a similar way to a bird’s gizzard, so they really don’t need teeth for the major component of their diet. To top it off, the teeth of Aardvarks are utterly unlike any other mammal teeth – they’re made of tubules of dentine (giving the Order the name ‘Tubulidentata’), with no enamel, no pulp-cavity and no root – so they keep on growing:

The weird teeth of the Aardvark, made up of tiny dentine tubules.

The weird teeth of the Aardvark, made up of tiny dentine tubules.

All of this suggests that their dentition is distinctly non-standard, so it probably isn’t just a vestigial feature inherited from a toothed ancestor – which reinforces the importance of the question ‘why do they have teeth?’

Bear with me.

A 60-80kg mammal living in hot and water-scarce regions of Africa, will struggle to get enough moisture from ants and termites to survive, even if they are nocturnal and sleeping in burrows during the hottest part of the day. So how do Aardvarks do it?

Cucumbers, that’s how.

There is actually a species of cucumber that has a symbiotic relationship with Aardvarks, and it’s unimaginatively, but descriptively, called the Aardvark Cucumber Cucumis humifructus Stent, 1927.

Aardvark cucumber. Image by B. Strohbach

Aardvark cucumber (not a golf ball). Image by B. Strohbach

These weird fruits develop deep underground and have a tough skin that keeps them viable for months. Outside they’re like a leather golfball, but inside they’re watery like the cucumbers you’d put in a Hendrick’s gin and tonic – and that’s where the Aardvarks get their moisture (the Cucumber, not the G&T).

Nothing but the Aardvark has a nose sensitive enough to detect the plant, or claws powerful enough to dig into the hard-baked earth to access the fruits (or possibly only an animal that mostly eats ants is desperate enough for some culinary excitement to go to all that effort for something that the rest of nature views as a lacklustre garnish). The Cucumber’s seeds need to pass through an Aardvark to become viable and those seeds get distributed underground with a healthy dollop of fertiliser in what is otherwise a harsh environment.

The leathery skin of the Cucumber is almost certainly the reason why Aardvarks are alone in having teeth amongst the termite and ant-eating mammals. It also explains why those teeth grow constantly – and why they get so worn down.

I think that’s pretty awesome.

Now you may be wondering if I’m making all this up, but honestly, the world really is that weird (and wonderful) when you look at it closely enough!

Friday mystery object #304

This week I was worried that I didn’t have a mystery object planned, but then I stumbled across this on my phone:

mystery304

 

It’s probably a bit too easy for some of you, so I’d encourage using some cryptic clues and hints to say what it is in the comments box below.

I’ve had a problem with spam comments recently and have switched on a filter to ensure that people’s first posts are approved (regular posters shouldn’t be affected) – fear not, I will be keeping an eye on it and approving first timers!

Have fun!

Friday mystery object #303 answer

Last week I gave you this mysterious bit of bone from the Thames to have a go at identifying:

mystery303b

A few ideas were put forward, but DrewM was spot on with the suggestion:

I think it’s the synsacrum of a bird, without the ilia fused – the foramina are for spinal nerves.

A synsacrum is a fused section of vertebrae including the sacrum (which is where the pelvis attaches to the spine). General opinion quickly agreed with that suggestion, but the taxonomic group that the synsacrum belongs to remained unguessed.

That is perhaps unsurprising, since it’s hard to find good comparative images of bird synsacra, especially with the hips and lateral (or side) bits knocked off and worn down.

chicken synsacrum

A Chicken synsacrum showing the section preserved in the mystery object

I had a go at looking through some of the comparative bird osteology collections at the Dead Zoo to get a feel for birds with a similar synsacral morphology.

The usual suspect for a bird bone found in the Thames (for me at least) is Chicken, since they’re so closely associated with humans and a lot of the bones washed up on the banks of the Thames are from butchery and food waste. The size was about right, but the vertebral centra (the middle bits) of the Chicken synsacrum become more narrow in the hip-line than in the mystery specimen.

Next I looked at ducks, whose centra taper more in the direction of the tail, then grebes whose whole synsacrum is more narrow overall:

grebe synsacrum

Synsacrum of a Great Crested Grebe

Eventually I made it to the gulls who seem to be a much better fit in terms of shape and the Herring Gull Larus argentatus Pontoppidan, 1763 was a good fit for size:

herring gull synsacrum

Herring Gull synsacrum

Now this doesn’t mean to say that the mystery object is certainly from a Herring Gull. I would want to have the object in my hand and comparative material available from several specimens to check the identification before being sure, but on the basis of the images that Keith Dunmall kindly provided, I think we’re in the right ball park.

More mysteries next week!

Friday mystery object #303

This week I have a real mystery object for you to try your hand at identifying. It’s from the River Thames and it was found by a strandline archaeologist who shared it with Keith Dunmall (who is a Youth Engagement Manager at @WaterAidUK) during a planning meeting for @Thamestidefest.

Keith shared it on Twitter looking for an identification, and he kindly sent me some extra pics:

mystery303amystery303bmystery303c

Do you have any idea what this might be?

No need for cryptic clues, I think this one may be tricky enough to be enough of a challenge as it is!

Have fun!

Friday mystery object #302 answer

Last week I gave you this egg to try your hand at identifying:

mystery302

Eggs can be tricky, since they are largely similar in shape and, since egg collecting was banned many years ago, there are few modern resources for identification.

However, you can pick up clues by thinking about colour and pattern and working out what advantage it may have. So you might expect a brightly coloured egg to be laid in a well disguised and deep nest, where it’s unlikely to be spotted except by the parent, whereas a yellowy speckled egg is more likely to be camouflaged if laid in a fairly open, sandy environment.

So this egg was probably laid somewhere near the sea, which means it’s probably from a charadriiform bird (those are the shorebirds).

Now there are a lot of shorebirds, but this egg is pretty big and it lacks the strongly conical shape you’d expect from a cliff-nester like a Guillemot (the shape means it rolls in tight circle, making it less likely to be blown or knocked off a cliff). That actually narrows it down to a handful of birds that makes comparison easier. Curlew eggs, for example, are a similar size, but they tend to be more grey and have larger blotches, plus they’re a bit less elongated.

This particular egg has the shape and colour of a gull egg and large size means it’s almost certainly the egg of a Greater Black-backed Gull Larus marinus Linnaeus, 1758.

I would say more, but at the moment I’m at the natural history highlight of the year – the NatSCA conference. Here’s the Twitter feed in case you’re interested in the discussion: