Here are the humerus and ulna of a pelican, bisected:

What we’re seeing here is the top third of each bone: humerus halves on the left, ulna halves on the right, in a photo taken at the 2012 SVPCA in one of our favourite museums.

The hot news here is of course the extreme pneumaticity: the very thin bone walls, reinforced only at the proximal extremely by thin struts. Here’s the middle third, where as you can see there is essentially no reinforcement: just a hollow tube, that’s all:

And then at the distal ends, we see the struts return:

Here’s the whole thing in a single photo, though unfortunately marred by a reflection (and obviously at much lower resolution):

We’ve mentioned before that pelicans are crazy pneumatic, even by the standards of other birds: as Matt said about a pelican vertebra (skip to 58 seconds in the linked video), “the neural spine is sort of a fiction, almost like a tent of bone propped up”.

Honestly. Pelican skeletons hardly even exist.


One of the field trips for last year’s SVPCA meeting was a jaunt to Nottingham to see the Dinosaurs of China exhibit at Wollaton Hall. We got to see a lot of stuff, including original fossils of some pretty famous feathered dinos – but of course what really captured our attention was the mounted Mamenchisaurus. This is a cast of the good old M. hochuanensis holotype specimen that has been put up all over the world, including in a car-park in Copenhagenon stilts in Chicago and even in a flooded basement in Slovenia.

Wollaton Hall houses the Nottingham Museum of Natural History, which is a fantastic trove of weird and wonderful things from around the world. We should really post about those things – I had them in mind when I was recently lamenting my lousy conversion rate of museum visit photos into blog posts. That will have to wait for another time. I’ll just note in closing that grand buildings and mounted sauropods go together like peanut butter and chocolate, and that this field trip was outstanding.

Mike Taylor, Matt Wedel, Darren Naish, and Bob Nicholls (kneeling) at Wollaton Hall, with Mamenchisaurus hochuanensis for scale.

Back in 2009, I posted on a big cervical series discovered in Big Bend National Park. Then in 2013 I posted again about how I was going to the Perot Museum in Dallas to see that cervical series, which by then was fully prepped and on display but awaiting a full description. Ron Tykoski and Tony Fiorillo (2016) published that description a couple of years ago, and after almost five years it’s probably time I posted an update.

I did visit the Perot Museum in 2013 and Ron and Tony kindly let me hop the fence and get up close and personal with their baby. I got a lot of nice photos and measurements of the big specimen. It’s an impressive thing. Compared to the other big sauropod cervicals I’ve gotten to play with, these vertebrae aren’t all that long – the two longest centra are about 80cm, compared to ~120cm for Sauroposeidon, Puertasaurus, and Patagotitan, and 137cm for Supersaurus (more details here) – but they are massive. According to the table of measurements (yay!) in Tykoski and Fiorillo (2016), which accord well with the measurements I took when I was there, the last vert is 117.5cm tall from the bottom of the cervical rib to the top of the neural spine, 98.4cm wide across the diapophyses, and has a cotyle measuring 29cm tall by 42cm wide. Here it is with me for scale:

I guarantee you, standing next to that thing and imagining it being inside the neck of a living animal is a breathtaking experience.

I failed in my mission in one way. In a comment on my 2013 post, I said, “I’ll try to get some good lateral views of the mount with as little perspective as possible.” But it can’t be done – the geometry of the room and the size of the skeleton don’t allow it, as Ron noted in the very next comment. There is one place in the exhibit hall where you can get the whole skeleton into the frame, and that’s a sort of right anterolateral oblique view. Here’s my best attempt:

So, this is an awesome specimen and you should go see it. As you can see from the photos, the vertebrae are right on the other side of the signage, with no glass between you and them, so you can see a lot. The rest of the exhibits are top notch as well. Definitely worth a visit if you find yourself within striking distance of Dallas.


Tykoski, R.S. and Fiorillo, A.R. 2016. An articulated cervical series of Alamosaurus sanjuanensis Gilmore, 1922 (Dinosauria, Sauropoda) from Texas: new perspective on the relationships of North America’s last giant sauropod. Journal of Systematic Palaeontology 15(5):339-364.

Left side, posterolateral oblique view, wide shot.

Same thing, close up.

Right side, lateral, wide.

Same thing, close up.

For more on this and other pneumatic sauropod tails, please see Wedel and Taylor (2013, here). And for more on the currently unresolved taxonomic status of FMNH P25112, see this post.

In her best-selling book, The Life-Changing Magic of Tidying Up, Marie Kondo argues that you should get rid of everything in  your life that doesn’t “spark joy”. I have accepted that I will never achieve Kondo-level simplicity, because too many things spark joy: a brass dinosaur my grandmother gave me when I was a kid, a worn penguin tibia I picked up on a beach in Uruguay, an Oklahoma rose rock, the alligator head Vicki brought me from New Orleans, an armadillo skull I found in the woods once, a sliced geode, an ammonite…the list goes on. Every area I have control over becomes, if not a cabinet of curiosities, at least a semi-organized array of curiosities.

An old box of stuff I unwrapped over the holidays. The human skull and allosaur claw are casts, all the other natural history items are real.

There are a couple of objects in my collection that give me more pleasure than any of the rest. One is a piece of shrapnel from the Sikhote-Alin meteorite – more about that another time, perhaps. The other is a 1.5″ tungsten cube.

I got the tungsten cube because of an answer on Quora to the question, “What is the most beautifully satisfying physics-based desk toy?” As the anonymous author of this particular answer wrote:

Some philistines may not consider this a proper “toy”, but I’ve had one for a year or so and am still crazy about it and have zero regret about purchasing it despite its high cost. It doesn’t do anything other than be way heavier than it seems possible for something that size to be. I think it’s mind-boggling and entertaining just to pick it up, hold it, savor its surreally strong attraction to the center of the earth, and think about gravity, matter, fundamental forces, etc.

The next time I got a nice chunk of fun money, I got the pair of 1.5″ tungsten and aluminum cubes sold by Midwest Tungsten Service. And a couple of years on, I gotta say, that purchase has probably given the best return of enjoyment per dollar of anything I’ve ever bought. For two reasons.

First, there’s the tactile enjoyment of picking up the tungsten cube. It is shockingly heavy. Pure tungsten has a specific gravity of 19.25. This cube is an alloy of 95% tungsten, 3.5% nickel, and 1.5% iron, called MT-18F by Midwest Tungsten. According to the fact sheet provided with the cube, “The addition of these alloying elements improves both the ductility and machinability of these alloys over non-alloyed tungsten, which can be brittle.” The addition of those other elements brings the cube’s density down to 18 g/cm^3. By comparison, steel is 8.05 and lead is 11.35. So even the alloyed cube still has a density more than half again that of lead. The 1.5″ cube has a mass of almost exactly 1 kg.

Even knowing, intellectually, how heavy the tungsten cube is, it’s still a kick in the brainpan every time I pick it up. It feels unreasonably, unnaturally heavy. It’s uncanny, like something out of a comic book, like it’s being pulled downward with the same force I normally associate with strong magnets.

The second reason why the cube is so great is the thoughts that it inspires. Pure tungsten has a melting point of 3422 °C (6192 °F). The W-Ni-Fe alloy, like other tungsten heavy alloys, “will begin to form a liquid phase when heated in excess of ~1450 °C (2642 °F)”, according to the Tungsten Heavy Alloy Design Manual (link). According to this page, most room fires max out at about 1200 °C, and according to this page, the temperatures of most magmas are 700-1300 °C (~1300-2400 °F). It is also extremely hard, with a Vickers hardness of 262 kgf/mm² (about 8.5 Mohs; regular steel is 4-4.5 and hardened steel is 7.5-8). The only harder substances are things like corundum; carbides of silicon, titanium, and tungsten; boron; and diamond.

So, seriously, what is going to destroy this cube? Burn down the house, and it will survive. Toss it into lava or magma, and it will sink to the bottom – even into the upper mantle – and sit comfortably, 150 °C or more below its melting point. If I owned beachfront property it would be cool to put the cube on a pebbly part of the beach and leave it there for a few years and see how – or if – it would erode. I know it can shatter if hit hard enough, but I imagine if it was just rolling around in the surf with some pebbles, the tungsten cube would wear down the pebbles and not vice versa. (It occurs to me that this could be tested with a small cube and a rock tumbler – I’ll let you know if I ever perform that experiment.)

My youngest brother, Ryan, designs drill bits for the oil industry, and then goes out to the drill sites to see how they wear down. His job is basically getting industrial diamond, tungsten carbide, and hardened steel to play well together at 1100 rpm. I wrote to get his profession opinion on the survivability of the tungsten cube.


I’m having a hard time thinking of some natural or accidental process that would destroy it. Volcano, asteroid, and A-bomb are all I’ve come up with. [This was before I’d looked up the temperature of magma.] Like, if it just got left out in the rain and the sun forever, would it corrode? Ever? How long could it be sitting there as a recognizable cube – a century, a millennium, 100,000 years?

Ryan (in an email with permission to cite):

I don’t have much experience with straight tungsten but WC [tungsten carbide] should fare better corrosion wise, it takes some pretty exotic stuff to corrode it. Now cobalt has a melting point of 2700F so if the WC got that hot the cobalt binder would melt, desintering the WC and breaking it down. However that’s way hotter than your average house fire.

Barring any natural disasters, acts of God, or man-made intervention, I would think you could set that thing on the ground somewhere and it would be just fine for a long, long time.

Fun fact #1: Pure tungsten oxidizes in air, so I imagine that’s one of the reasons they added the nickel in the MT-18F.

Fun fact #2: Ni and Co have very similar melting points. [Meaning that my W-Ni-Fe cube will desinter at about the same temp as tungsten carbide, which uses cobalt instead of nickel as the binder.]

My desk at work. Aquilops and sea otter skulls on the left are casts, the ichthyosaur is a 3D print, and everything else is real and mostly collected and prepped by me. That’s the aluminum cube in the back on the far left. The tungsten cube sits on my side of the desk, where I can play with it.

Now, I have a lot of things that I hope will outlive me, including a lot of old books and reprints. And a lot of that stuff is pretty durable, including the aforementioned meteorite chunk. But there is a big difference between holding a century-old monograph and hoping that the people who come after me will care for it, and holding the tungsten cube and knowing that it will most certainly survive for centuries or millennia, unless someone attempts to destroy it, deliberately and with a non-trivial expenditure of effort.

And that’s why I’m writing about the tungsten cube here on what is normally my fossil blog. I am surrounded by objects that represent time – developmental time for bones, geologic time for fossils and minerals, astronomical time for meteorites – but these are almost all natural products that embody the past. The tungsten cube is a human product, and in its sheer durability – and survivability – it embodies the future. It will exist in future iterations of this world that I can’t imagine. That’s a breathtaking thought.

If you’re thinking about getting a chunk of tungsten, I strongly recommend the 1.5″ cube set. A few months after picking it up, I got a 0.5″ cube of the same stuff, just to see what it would be like. It’s heavy for its size, but it’s not heavy enough to be shocking. The visceral reaction is more “huh” than “WOW!!”

It’s worth getting the set because the aluminum cube is also entertaining and it’s worth the small additional outlay (as of this writing, $133 for the 1.5″ tungsten cube alone, and $159 for the pair). The aluminum cube has a mass of 0.15 kg, exactly 15% that of the tungsten cube. I have visitors pick up the aluminum cube first. It’s funny, I guess a lot of folks haven’t had a chance to play with solid chunks of metal firsthand because they’ll pick up the aluminum cube and say, “Wow, that’s heavier than I expected.” At that point I just smile. The tungsten cube blows people away, every time. Heck, it blows me away every time, and I’ve been playing with it for two years. Highly recommended.

For a full line of cubes, spheres, and tops, check out Midwest Tungsten Service (link). Many of their products are also available on Amazon.

Back in the spring of 1998, Kent Sanders and I started CT scanning sauropod vertebrae. We started just to get a baseline for the Sauroposeidon project, but in time the data we collected formed the basis for my MS thesis, and for a good chunk of my dissertation as well. Mostly what we had available to scan was Morrison material. Between imperfect preservation, inexpert prep (by WPA guys back in the ’30s), and several moves over the decades, most of the verts from the Oklahoma Morrison have their neural spines and cervical ribs broken off. One of the first things I had to figure out was how to tell broken vertebrae of Camarasaurus from those of Apatosaurus (at the time; Brontosaurus is back in contention now). Here’s a thing I made up to help me sort out cervical centra of Camarasaurus and whatever the Oklahoma apatosaurine turns out to be. It’s a recent production, but it embodies stuff from my notebooks from 20 years ago. Should be useful for other times and places in the Morrison as well, given the broad spatiotemporal overlap of Camarasaurus and the various apatosaurines.

For a related thing in the same vein, see Tutorial 30: how to identify Morrison sauropod cervicals.

More elephant seals soon, I promise.

UPDATE 20 Feb 2018

Ken Carpenter sent this by email, with a request that I post it as a comment. Since it includes an image, I’m appending to the post, because it makes an important point that I neglected to mention.

Camar post cerv

Ken: Sorry, Matt. Not so easy. The last cervical of Camarasaurus from the Cleveland Lloyd Quarry is more apatosaurine-like than Camarasaurus-like based on your posting. Note the position of both zygapohyses with both ends of the centrum.

My response: Yes, good catch. I meant to say in the post that my distinguishing characters break down at the cervico-dorsal transition. Even so, in this Cleveland Lloyd vert the postzyg is still forward of a line drawn directly up from the cotyle. I’ve never seen that in an apatosaurine–going into the dorsal series, the postzygs tend to be centered over a line projected up from the rim of the cotyle. (If anyone knows of counterexamples, speak up!)

For distinguishing cervico-dorsals, apatosaurines tend to have much taller neural spines than Camarasaurus, and this carries on through the rest of the dorsal series. In apatosaurine dorsals, the height of the spine above the transverse processes always equals or exceeds the height of the arch below the transverse processes. In Camarasaurus, the height of the dorsal neural spines is always less than or equal to the height of the arch. The shapes of the spines are fairly different, too. Maybe that will be the subject of a future post.

Open-access journalist Richard Poynder posted a really good interview today with the Gates Foundation’s Associate Officer of Knowledge & Research Services, Ashley Farley. I feel bad about picking on one fragment of it, but I really can’t let this bit pass:

RP: As you said, Gates-funded research publications must now have a CC BY licence attached. They must also be made OA immediately. Does this imply that the Gates foundation sees no role for green OA? If it does see a role for green OA what is that role?

AF: I wouldn’t say that the foundation doesn’t see value or a role for green open access. However, the policy requires immediate access, reuse and copyright arrangements that green open access does not necessarily provide.

Before I get into this, let me say again that I have enormous admiration for what Ashley Farley and the Gates Foundation are doing for open access, and for open scholarship more widely. But:

The (excellent) Gates policy requires immediate access, reuse and copyright arrangements that gold open access does not necessarily provide, either. It provides them only because the Gates Foundation has quite rightly twisted publishers’ arms, and said you can only have our APCs if you meet our requirements.

And if green open access doesn’t provide immediate access and reuse, then that is because funders have not twisted publishers’ arms to allow this.

It’s perfectly possible to have a Green OA repository in which all the deposited papers are available immediately and licenced using CC By. It’s perfectly possible for a funder, university or other body to have a green OA policy that mandates this.

But it’s true that no-one seems to have a green OA policy that does this.

Why not?