The equine interspinal ligaments of Ray Wilhite
March 13, 2023
Our old friend Ray Wilhite sent us this glorious photo of a horse neck that he dissected recently, with permission to post here:
The big yellow sheet at the top is the nuchal ligament, which in many mammals provides axial tension for the cervical vertebrae, and which has been hypothesized (e.g. by Alexander 1985:13) to have existed and provided similar support in at least some sauropods.
But what caught Ray’s eye was the smaller interspinal ligaments running horizontally between the neural spines of the consecutive vertebrae. The literature doesn’t talk about these much because the irresistible glamour of the nuchal ligament grabs everyone’s attention, but they’re there in pretty much everything, being primitive for tetrapods.
Here they are again in absolutely glorious detail. (Seriously, click through for the full-sized version. You can all but make out individual cells.)
Many thanks to Ray for sharing these photos with us!
Museum of Osteology, June 2018 visit
December 13, 2018
Click to embiggen. Trust me.
Last year about this time I wrote:
Here’s a stupid thing: roughly 2-3 times a year I go to the field or to a museum and get hundreds of SV-POW!-able photos. Then I get back to the world and catch up on all of the work that piled up while I was away. And by the time I’m done with that, whatever motivating spark I had – to get some of those photos posted and talk about the exciting things I figured out – has dissipated.
The museum I was thinking about more than any other when I wrote that is the Museum of Osteology in Oklahoma City. I don’t get there every year, but I stop in as often as possible, and I make it more years than not. And yet, looking back through the archives I see that almost all of my posts about the Museum of Osteology came in a brief flurry five years ago. Shameful!
This summer I was out in the Oklahoma panhandle for fieldwork with Anne Weil, then I had a very quick day in the collections at the OMNH in Norman, then I had to drop my son London with relatives (he stayed for an extra week) and hop a plane home. In between the kid hand-off and the drop-dead get-to-the-airport time I had exactly one spare hour, so of course I hit the museum.
UPDATE: for the curious, here’s the signage for the hanging humpback whale skeleton.
The Museum of Osteology is easily one of my favorite natural history museums in the world. Like all my favorite museums, it just packed to the gills with actual natural history objects. The signage is tasteful, informative, and discreet, and there is a blessed absence of blaring videos, rotating 3D whatsits, and interactive geegaws to ruin the experience.* You can walk all the way around the big mounted skeletons with no glass in the way. The staff are friendly and helpful, and as you can see from the photos, they even provide comfortable benches for people who wish to sit and ponder the endless forms most beautiful.
That, folks, is a damn fine museum.
* To be clear, I don’t think all videos and interactive displays are evil. But they need to enhance the experience of natural history, not be a substitute for it, and that’s a distinction that seems lost on many exhibit designers.
I was taken by this conjunction of two water-adapted artiodactyls.
Here’s the hippo by itself if you want the whole skeleton.
And a rhino to round out the big African megafauna. I showed the giraffe in this old post.
Even familiar animals that you may think you know front-to-back are often presented in new and interesting ways. I adore this horse skull, which has the maxilla and mandible dissected to show the very tall, ever-growing teeth, which erupt continuously through the horse’s life until the crowns are entirely worn away.
The textures on this giraffe skull are pretty mind-blowing.
I strongly recommend zooming in and tracing out some blood vessel pathways, especially over the orbit, at the bases of the ossicones, and in the temporal fossa (below the ossicones and behind the orbit).
Bottom line, if you are interested in the natural world at all, you owe it to yourself to visit this museum. And you’ll want to go as heavy in the wallet as you can manage, because the gift shop is ridiculous and can easily eat 30-45 minutes and all your disposable income. Take it from a survivor.
We may never know how flexible sauropod necks were
November 8, 2018
The more I look at the problem of how flexible sauropod necks were, the more I think we’re going to struggle to ever know their range of motion It’s just too dependent on soft tissue that doesn’t fossilise. Consider for example the difference between horse necks (above) and camel necks (below).
The skeletons of both consist of vertebrae that are pronouncedly opisthocoelous (convex in front and concave behind), so you might think their necks would be similarly flexible.
But the balls of horse cevicals are deeply embedded in their corresponding sockets, while those of camels have so much cartilage around and between them that the tip of the ball doesn’t even reach the rim of the socket. As a result of this (and maybe other factors), camel necks are far more flexible than those of horses.
Which do sauropod necks resemble? We don’t currently know, and we may never know. It will help if someone gets a good handle on osteological correlates of intervertebral cartilage.
[This post is recycled and expanded from a comment that I left on a Tetrapod Zoology post, but since Tet Zoo ate that comment it’s just as well I kept a copy.]
Cool things happening elsewhere: three links
May 1, 2018
This will be a short and mostly navel-gaze-y collection of links.
Back in November, 2016, I posted here about my “Twelve Steps to Infinity” article in Sky & Telescope magazine. That one covered 12 objects in the winter sky and corresponding events in Earth history when the light we see now left those objects. I’ve now done a similar but larger article for the summer sky, titled “Fifteen Steps to Forever”, which is out in the June issue of Sky & Tel. Also, the June issue has not one but three articles on space rocks and their terrestrial traces: one on where we are as a species in assessing the impact threat (timely since I was just talking about that), one on how to see impact craters from commercial airliners (awesome!), and one on upcoming asteroid sample-return missions being prepped by the Japanese space agency and NASA. Confusingly, the June issue will be on newsstands during the month of May, so if you want to check it out, now’s the time.
More recently, in the unexpectedly popular tungsten cube post I wrote:
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.
“Another time” has come – in the wake of my impact talk, I’m slowly going through my (small) meteorite collection over at 10 Minute Astronomy. I just covered my Sikhote-Alin chunk, in what I immodestly think is one of my better posts. Go see if you agree.
Finally, you presumably came here in hopes of seeing the anatomy from something, so here you go. My friend and colleague Jessie Atterholt is on Instagram as @theladyanatomica and she has been posting some pretty sweet photos and videos, mostly of specimens she prepared herself. I’m highlighting her work now because she just posted a video of her horse foot mount, which is free-standing with the help of a single rod, but which breaks almost all the way down thanks to metal pins and magnets. It’s one of my favorite anatomical preparations of all time and something I both envy and covet. Peter Dodson has one in his office – Jessie made it for him when she was his student at UPenn. Seeing it when I was in Philadelphia in March re-fired my interest in such things – if you’ve noticed an uptick in posts about anatomical specimens in the last few weeks, Peter and (mostly) Jessie are to blame. With any luck, I’ll have something similar of my own to post on in the not-too-distant future. In the meantime, go check out Jessie’s work at the link above.
Sauropod Vertebra Picture of the Week 