2018 at SV-POW!

December 31, 2018

Last year about this time I vowed to return SV-POW! to its nominal roots: a new post at least once a week for all of 2018. It had been a while since the blog had lived up to the letter of its name, and I thought it would be a fun challenge to see if blogging to a schedule again would be inspiring or oppressive.

Then I went and had probably the busiest year of my professional career: 12 invited talks in 5 different states, 12 visits to museum collections or research labs, plus another 3 visits to museum public galleries for fun, 4 trips for fieldwork, 3 conference presentations, and more CT scanning than I have done since the last millennium. Happily, I am not the sole proprietor here and Mike and I can take turns driving when the other is occupied.

So how’d we do?

In January I blogged about weird neural canals, part of an obsession that would occupy most of my mental bandwidth this year, and also about the impact of Don Glut’s New Dinosaur Dictionary when I was a kid. A post on sauropod gigantism sparked a very active discussion that ran to 47 comments, which is a rarity these days.

Gonzalez Riga et al. (2018: figure 6). Mendozasaurus neguyelap cervical vertebra (IANIGLA-PV 076/1) in (A) anterior, (B) left lateral, (C) posterior, (D) right lateral, (E) ventral and (F) dorsal views. Scale bar = 150 mm. Sorry it’s monochrome, but that’s how it appears in the paper.

February was mostly run-of-the-mill posts on vertebral morphology and open access. The standouts were Mike’s post on weird cervical vertebrae and my unexpectedly popular off-topic post on the durability of tungsten. I see that my teaser post on a trip to see elephant seals has not yet been followed up. There’s a lot of that around here–we’re often too busy with the next thing to finish up the last thing. I’ve given up feeling bad about that, and accepted that it’s just how we roll.

Mike ruled March with a flurry of posts, including a couple worth revisiting on how grant funding is awarded and on the state of play vis-a-vis Big Publishing. Also (and uncharacteristically) Mike posted on appendicular bones of birds, both skinny and fat. It was left to me to represent for sauropods, with posts on the cervical vertebrae of Alamosaurus and Suuwassea and some noodling about sauropod skin.

I flew solo in April, with some posts derived from my spring travels. A very long post on the suitability of dinosaur femora as clubs was good, goofy fun, but an arresting video of a rhino going ass-over-teakettle and getting up unhurt, and the humility that should inspire in us, is the clear standout for the month.

In May I started CT scanning sauropod vertebrae again and went to Utah for the first of several stints of fieldwork this year. Mike started work on the Archbishop (allegedly), and blogged about Argentinosaurus poop. My series on bird neural canals, represented by these posts (two links) is still incomplete, and has now been superseded by the Haplocanthosaurus presentation at the 1st Palaeontological Virtual Congress.

June was comparative anatomy month here at SV-POW!, with Mike posting on the dead things in his woodshed, and me writing about exploded turtles and the amazing collection of anatomical preparations in Peter Dodson’s office. I also managed two posts about field adventures in the Oklahoma panhandle.

Figure 4. Centra and neural arches of posterior dorsal vertebrae from two rebbachisaurid sauropods (not to scale), highlighting the distinctive “M” shape formed by laminae on the lateral face of the neural arch. A. NHMUK PV R2095, the holotype and only vertebra of Xenoposeidon proneneukos. B. MNHN MRS 1958, a posterior dorsal vertebra from the holotype specimen of Rebbachisaurus garasbae.

In July Mike and I returned to our regular dance partners. For Mike, that meant serious and whimsical posts about Xenoposeidon, which for a few months held the title of the oldest known rebbachisaur. I had Haplocanthosaurus caudals on the brain, both old and new. Posts on fieldwork in Oklahoma and Utah bookended the month.

My fascination with Haplocanthosaurus extended into August, and I CT scanned a Diplodocus caudal and attended a pterosaur conference. Mike kicked off a discussion about vertebral orientation with a pair of posts that would eventually lead to our presentation on the topic at the 1st Palaeo Virtual Congress. And I see that I still owe the world a “down in flames” perspective on my own career.

In September the vertebral orientation discussion expanded to take in the Brachiosaurus holotype and Komodo dragons, and Mike blogged about imposter syndrome. The most personally satisfying event in September was that Jessie Atterholt and I started to get the word out about some of the collaborative research we’ve been doing in the past year, with her very well-received talk at SVPCA and the archiving of our abstract and slideshow on PeerJ Preprints.

October saw the return of #MikeTaylorAwesomeDinoArt, and the 2018 TetZooCon, and #MikeTaylorAwesomeDinoArt at TetZooCon. I also had a return to form, with a series of posts about pneumaticity, and a batch of new paleo-memes. The biggest actual news was the enigmatic Amphicoelias fragillimus dethroning Xenoposeidon as the new world’s oldest rebbachisaur.

November was entirely representative of SV-POW!, with an eclectic grab-bag of posts on a museum mount, neck flexibility, a historical illustration, bird vertebrae, academic publishing, and what is probably our real favorite dinosaur (no matter what we might say when asked in interviews or in person): the insanely overbuilt Apatosaurus.

This month we’re closing out the year with posts on dissecting a pig head, our presentations at the 1st Palaeo Virtual Congress, the open birth of the vertebral orientation paper, a long overdue post on cleaning bird vertebrae, and this, our first yearly retrospective.

The Salutary Effects of Blogging

This blog started as a joke, and we thought we’d see if we could keep up the gag for a whole year. But it very rapidly evolved into something much more serious, in a way that none of us expected. SV-POW! doesn’t just give us a forum to interact with you, our colleagues. It also forces us to talk to each other, regularly, about subjects that we care about. I love reading Mike’s posts, because after all this time, I still often have no idea what he’s going to say. After 18 years of friendship, 14 joint conference presentations, 11 years of blogging together, and 7 coauthored papers, we still regularly surprise each other with unexpected observations and provocative questions. Not only do we not always agree, we very often disagree, but we disagree constructively. Neither of us is willing to let a subject drop until we’ve gotten to the root of the disagreement, and that process sharpens us both.

Bottom line, we both need SV-POW! Not only as a forum for discussion, although that’s rewarding, or as a soapbox, although that’s sometimes useful, or a generator of occasionally publishable ideas, although that’s an unexpected bonus. We need to blog here because it forces us to keep learning what we think and what we know, both individually and as a team. If you enjoy the output or find it interesting or infuriating or worth thinking about, we’re happy — honored, in fact. But at this point I think we would keep blogging if there was no audience at all. It is a whetstone for our minds.

Let’s see what 2019 will bring. Happy New Year, everyone! We’ll see you in the future.

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A simply mind-blowing preparation of the skull of an American paddlefish, Polyodon spathula. In life the paddle-shaped snout is covered by thousands of electroreceptors that detect the swarms of zooplankton on which the paddlefish feeds.

This was on display in the gift shop at the Museum of Osteology in Oklahoma City when I visited in July of this year. I was relieved it wasn’t for sale, first because it truly would have bankrupted me, and second because as a fellow excavator of antiquities once said, “It belongs in a museum!”

When I started working on sauropods, I thought their vertebrae were cool but they were loaded with weird structures that I didn’t understand. Then I dissected my first ostrich neck and suddenly everything made sense: this was a muscle attachment, that was a pneumatic feature, this other thing was a ligament scar. Everyone who is interested enough to read this blog should give themselves the same “Aha!” moment. You don’t even have to eat the birds yourselves, lots of people don’t like bird necks and will give them away if you ask.

If you get a whole bird, the neck is usually included with the giblets. Around Thanksgiving and Christmas you can often find bundles of spare turkey necks at your grocer or butcher.

This spring I picked up some smoked turkey necks at the grocery store. I wanted to make turkey stew and I figured I might as well get some toys in the bargain. Here are some neck segments in the crock pot.

And here they are after a few hours of cooking. Time to separate the meat from the bones. That neck segment in the middle of the above photo is a pretty good match for the ostrich neck cross-section in this post.

Here are parts of three vertebrae with the long, multi-segment muscles removed, but with the shorter single-segment muscles still connecting them. Anterior is to the right; that’s a cervical ribs sticking out at the lower right “corner”.

Here’s a single intact cervical in left lateral view with most of the meat off, but ready for a long simmer to loosen the remaining crud. This is roughly the same orientation as the lateral view of Mike’s famous turkey cervical.

Meat goes back in the pot.

Bones go on to the next stage: simmering. One of the nice things about the stepwise process of cleaning bones is that you can stop at any point, put the bones in the freezer, and come back days or months later. This bowl of bones went into the freezer in exactly the state you see here, and I didn’t pull them out and finish cleaning them until last week.

If you have a pot-sized strainer, it makes things easier, especially for rinsing. These aren’t turkey vertebrae, these are the verts from my Thanksgiving ducks. But the principle and the process are the same.

After simmering for an hour or two, it’s time to pick off the loosened muscles, ligaments, cartilage, and so on. Here are two similar turkey cervicals after simmering, in dorsal view with anterior to the right. The one on the left has not been cleaned and has all kinds of crud stuck to it, including a big chunk of intervertebral ligament sticking out between the rami of the postzygapophyses. The one on the right has been through a first-pass cleaning.

What tools should you use? Whatever you have to hand. I like old toothbrushes for scrubbing off little bits of muscle and tendon, toothpicks for shoving spinal cord bits through the neural canal and for picking bits of meat out of hard-to-reach places, and the Mark 1 thumbnail for planing off articular cartilage, as shown here with the back end of a duck cervical.

Here’s the outcome of a cleaning session: on the left, the bowl I used for cleaning the vertebrae. In the top middle, the pile of gloop I pulled off. And on the right, a bowl of cleaned turkey and duck vertebrae, ready for degreasing.

Here are the vertebrae of a couple of ducks after soaking overnight in 3% hydrogen peroxide, the ordinary stuff you get at the drugstore or dollar store.

Here’s another bowl with turkey vertebrae. They were all at the bottom of the bowl when I went to bed, floating when I got up the next morning. This is pretty common with lightweight pneumatic vertebrae: the oxygen bubbling out of the hydrogen peroxide has gotten trapped in the internal air spaces and made the vertebrae buoyant.

After a night in the hydrogen peroxide, it’s time to rinse and dry the vertebrae. I put this mixed lot of turkey and duck verts on a plate with a paper towel and left them out on the kitchen counter. In the summertime, when it’s hot and dry, I might put them outside for a bit and they’d be dry in a couple of hours. Indoors in the winter it can take a couple of days for the vertebrae to get completely dry.

Here’s the same batch of vertebrae a couple of days later, clean and dry and ready for whatever comes next.

Which bird should you use? Bigger birds have vertebrae that are easier to clean, harder to damage, and more fun to look at, but use whatever you can get your hands on. This photo shows the axis, a middle cervical, and a posterior cervical from the turkey (top) and duck (bottom). Note that the duck was so young that the cervical ribs hadn’t fused and they fell off during the cleaning process.

If you’ve been following along, you have some nice clean bird vertebrae to play with. So what now — what should you do with them? That will the subject of an upcoming post. Stay tuned!

In a move that will surprise no-one who’s been paying attention, my and Matt’s presentation of vertebral orientation at the 1st Palaeo Virtual Congress is now up as a PeerJ preprint. Sadly, with the end of the conference period on 15th December, the page for my talk has been deleted, along with some interesting comments. But here at SV-POW!, we have no truck with ephemerality, hence this more permanent manifestation of our work.

Matt’s preprint consists of the abstract, and has the slide deck as a supplementary data file. That’s what he submitted to the conference, with attendees invited to page through it. By contrast, I recorded a video of my talk. I am trying to get that attached to my preprint, but as things stand it’s not there because it’s too big (at 65 Mb).

Meanwhile — and indeed in perpetuity — you can just watch it on YouTube, where I also uploaded it. In the end, that may be a more practical way of making video available anyway, but I do want the preservational benefit of lodging it with a preprint.

Remember, we’re working on the paper in the open. We’d love to get input from you all, and especially from anyone who’s run into this problem before with other taxa. Please, if you have fifteen minutes spare, watch the talk and leave any comments you have: here, on the preprint, on the YouTube page, or as issues in the GitHub tracker!

Reference

Turkeys lie

December 18, 2018

We all know what turkeys look like, right?

Turns out that two thirds of that bird is a lie. Here’s a diagram produced for hunters on which part of the turkey to shoot. (It’s all over the Internet, and I can’t trace the original source, but I got it from here):

Bascially, if you fire an arrow at a visible turkey, there’s a 2/3 chance that it’ll pass straight through feathers and completely miss the actual bird.

Now, then: what do we think a theropod looked like in life? Probably not much like what skeleton reconstructions show as the flesh envlope, as for example in Scott Hartman’s Guanlong:

Instead, it might have looked like this:

(Note: this is not in any way a criticism of Scott’s fine work, which is a scientific restoration of the soft tissue, and does not address integument at all.)

And now that pterosaurs have feathers, too(*), we have to assume that they, too, probably had body outlines bearing little resemblance to the flesh-on-bone shapes we’ve been used to seeing.

 


(*) As Matt pointed out: “I can’t be bothered to write “integumentary structures” when I mean “feathers”. I realize they may be independently derived, but eyes evolved independently like 40 times and we don’t refer to the other 39 instances as “photoreceptive structures”.” (He actually wrote “I can’t be arsed”, but I changed it to “bothered” to make him appear more professional.)

 

If you were curious about the Wedel et al. presentation on the Snowmass Haplocanthosaurus at the 1st Palaeo Virtual Congress but didn’t attend the event, it is now preserved for posterity and freely available to the world as a PeerJ Preprint (as promised). Here’s the link.

I’ll have much more to say about this going forward, but for now here are slides 20 and 21 on the intervertebral joint spaces. This is obviously just the same vert cloned three times and articulated with itself. With the digital rearticulation of the reconstructed and retrodeformed caudal series still in progress, we cloned caudal 3, the only vertebra that preserves both sets of zygapophyses, to get a rough estimate of the sizes and shapes of the soft tissues that filled the intervertebral spaces and neural canal.

The reconstructed intervertebral discs (in blue) are very crude and diagrammatic. The reason I’m putting these particular slides up is to get the cited references out in the open on the blog, to start correcting the misapprehension that all non-mammalian amniotes have exclusively synovial intervertebral joints (see the discussion in the comments on this post). In the list below I’m including Banerji (1957), which is not cited in the presentation but which I did cite in that comment thread; it’s an important source and at least for now it is a free download. These refs are just the tip of a very big iceberg. One of my goals for 2019 is to do a series of posts reviewing the extensive literature on amphiarthrodial (fibrocartilaginous) intervertebral joints in living lepidosaurs and birds. Stay tuned!

And please go have a look at the presentation if you are at all interested or curious. As we said in the next to last slide, “this research is ongoing, and we welcome your input. If there are facts or hypotheses we haven’t considered but should, please let us know!”

References

Now that Matt and I have blogged various thoughts about how to orient vertebra (part 1, part 2, relevant digression 1, relevant digression 2, part 3) and presented a talk on the subject at the 1st Palaeontological Virtual Congress, it’s time for us to strike while the iron is hot and write the paper.

Figure A. NHMUK PV R2095, the holotype dorsal vertebra of Xenoposiedon proneneukos in left lateral view. A. In the canonical orientation that has been used in illustrations in published papers (Taylor and Naish 2007, Taylor 2018b, in blog-posts and on posters and mugs. B. Rotated 15° “backwards” (i.e. clockwise, with the dorsal portion displaced caudally), yielding a sub-vertical anterior margin in accordance the recommendation of Mannion (2018b). In both parts, the blue line indicates the horizontal axis, the green line indicates the vertical axis, and the red line indicates the slope of the neural arch as in Taylor (2018b: figure 3B, part 2). In part A, the slope (i.e. the angle between the red and green lines) is 35°; in part B, it is 20°.

We’re doing it totally in the open, on GitHub. You can always see the most recent version of the manuscript at https://github.com/MikeTaylor/palaeo-vo/blob/master/vo-manuscript.md and you can also review the history of its composition if you like — from trivial changes like substituting a true em-dash for a double hyphen, to significant additions like writing the introduction.

More than that, you can contribute! If you think there’s a mistake, or something missing that should be included, or if you just have a suggestion, you can file an issue on the project’s bug-tracker. If you’re feeling confident, you can go further and directly edit the manuscript. The result will be a tracked change that we’ll be notified of, and which we can accept into, or reject from, the master copy.

We hope, by making all this visible online, to demythologise the process of writing a paper. In a sense, there is no magic to it: you just start writing, do a section at a time, revise as you go, and eventually you’re done. It’s much like writing anything else. (Doing the referencing can make it much slower than regular writing, though!)

By the way, you may wonder why the illustration above is “Figure A” rather than “Figure 1”. In all my in-progress manuscripts, I just assign letters to each illustration as I add it, not worrying about ordering. Only when the manuscript is ready to be submitted do I take the order that the illustrations occur in (A, D, G, H, B, I, E, F, for example, with C having been dropped along the way) and replace them with consecutive numbers. So I save myself a lot of tedious and error-prone renumbering every time that, in the process of composition, I insert an illustration anywhere before the last existing one. This is really helpful when there are a lot of illustrations — as there tend to be in our papers, since they’re all in online-only open-access venues with no arbitrary limits. For example, our four co-authored papers from 2013 had a total of 69 illustrations (11 in Taylor and Wedel 2013a, 25 in Wedel and Taylor 2013a, 23 in Taylor and Wedel 2013b and 10 in Wedel and Taylor 2013b).

References