Published May 15, 2021 | https://doi.org/10.59350/2r611-wg227

Haplocanthosaurus neural canals are weird, part 1: in which we tell the world

  • 1. ROR icon Western University of Health Sciences
Feature image

{.wp-image-18964 .size-large aria-describedby="caption-attachment-18964" loading="lazy" attachment-id="18964" permalink="http://svpow.com/2021/05/15/haplocanthosaurus-neural-canals-are-weird-part-1-in-which-we-tell-the-world/wedel-et-al-haplo-neural-canals-fig-1/" orig-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-1.jpg" orig-size="2000,2000" comments-opened="1" image-meta="{"aperture":"0","credit":"","camera":"","caption":"","created_timestamp":"0","copyright":"","focal_length":"0","iso":"0","shutter_speed":"0","title":"","orientation":"0"}" image-title="Wedel et al – Haplo neural canals – fig 1" image-description="" image-caption="" medium-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-1.jpg?w=300" large-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-1.jpg?w=1024" width="480" height="480" srcset="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-1.jpg?w=480 480w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-1.jpg?w=960 960w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-1.jpg?w=150 150w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-1.jpg?w=300 300w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-1.jpg?w=768 768w" sizes="(max-width: 480px) 100vw, 480px"}

A. Recovered skeletal elements of Haplocanthosaurus specimen MWC 8028. B. Caudal vertebra 3 in right lateral view. C. The same vertebra in posterior view. Lines show the location of sections for D and E. D. Midsagittal CT slice. The arrow indicates the ventral expansion of the neural canal into the centrum. E. Horizontal CT slice at the level of the neural arch pedicles, with anterior toward the top. Arrows indicate the lateral expansions of the neural canal into the pedicles. B-E are shown at the same scale. Wedel et al. (2021: fig. 1).

New paper out today:

Wedel, Mathew; Atterholt, Jessie; Dooley, Jr., Alton C.; Farooq, Saad; Macalino, Jeff; Nalley, Thierra K.; Wisser, Gary; and Yasmer, John. 2021. Expanded neural canals in the caudal vertebrae of a specimen of Haplocanthosaurus. Academia Letters, Article 911, 10pp. DOI: 10.20935/AL911 (link)

The paper is new, but the findings aren't, particularly. They're essentially identical to what we reported in our 1st Paleo Virtual Conference slide deck and preprint, and in the "Tiny Titan" exhibit at the Western Science Center, just finally out in a peer-reviewed journal, with better figures. The paper is open access and free to the world, and it's short, about 1600 words, so this recap will be short, too.

{.wp-image-18967 .size-large aria-describedby="caption-attachment-18967" loading="lazy" attachment-id="18967" permalink="http://svpow.com/2021/05/15/haplocanthosaurus-neural-canals-are-weird-part-1-in-which-we-tell-the-world/wedel-et-al-haplo-neural-canals-fig-2-v2/" orig-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-2-v2.jpg" orig-size="3500,1855" comments-opened="1" image-meta="{"aperture":"0","credit":"","camera":"","caption":"","created_timestamp":"0","copyright":"","focal_length":"0","iso":"0","shutter_speed":"0","title":"","orientation":"0"}" image-title="Wedel et al – Haplo neural canals – fig 2 v2" image-description="" image-caption="" medium-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-2-v2.jpg?w=300" large-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-2-v2.jpg?w=1024" width="480" height="254" srcset="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-2-v2.jpg?w=480 480w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-2-v2.jpg?w=958 958w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-2-v2.jpg?w=150 150w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-2-v2.jpg?w=300 300w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-2-v2.jpg?w=768 768w" sizes="(max-width: 480px) 100vw, 480px"}

A. Photograph of a 3D-printed model of the first three caudal vertebrae of Haplocanthosaurus specimen MWC 8028, including endocasts of the neural canal (yellow) and intervertebral joints (blue), in right lateral view, and with the neural canal horizontal. B. Diagram of the same vertebrae in midsagittal section, emphasizing the volumes of the neural canal (yellow) and intervertebral joint spaces (blue). Anterior is to the right. Wedel et al. (2021: fig. 2).

John Foster and I described Museum of Western Colorado (MWC) specimen 8028, a partial skeleton of Haplocanthosaurus from Snowmass, Colorado, in late 2014. One weird thing about that specimen (although not the only weird thing) is that the neural canals of the tail vertebrae are bizarrely expanded. In most vertebrae of most critters, the neural canal is a cylindrical tunnel, but in these vertebrae the neural canals are more like spherical vacuities.

John and I didn't know what to make of that back in 2014. But a few years later I started working with Jessie Atterholt on bird anatomy, which led me to do a little project on the whole freaking zoo of weird stuff that birds and other dinosaurs do with their neural canals, which led to the 1PVC presentation, which led to this. 

{.wp-image-18970 .size-large aria-describedby="caption-attachment-18970" loading="lazy" attachment-id="18970" permalink="http://svpow.com/2021/05/15/haplocanthosaurus-neural-canals-are-weird-part-1-in-which-we-tell-the-world/wedel-et-al-haplo-neural-canals-fig-3/" orig-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg" orig-size="1648,1773" comments-opened="1" image-meta="{"aperture":"0","credit":"","camera":"","caption":"","created_timestamp":"0","copyright":"","focal_length":"0","iso":"0","shutter_speed":"0","title":"","orientation":"0"}" image-title="Wedel et al – Haplo neural canals – fig 3" image-description="" image-caption="" medium-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg?w=279" large-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg?w=952" width="480" height="516" srcset="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg?w=480 480w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg?w=960 960w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg?w=139 139w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg?w=279 279w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg?w=768 768w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-3.jpg?w=952 952w" sizes="(max-width: 480px) 100vw, 480px"}

Caudal vertebra 3 of Haplocanthosaurus specimen MWC 8028 in left posterolateral (A), posterior (B), and right posterolateral (C) views, with close-ups (D and E). In A and B, a paintbrush is inserted into one of the lateral recesses, showing that the neural canal is wider internally than at either end. Wedel et al. (2021: fig. 3).

Of course there will be more posts and more yapping, as signaled by the 'Part 1' in the post title. Although I am extremely satisfied with the streamlined, 1600-word missile of information and reasoning that just dropped, there are parts that I want to unpack, that haven't been unpacked before. But the paper launched at midnight-thirty, Pacific Daylight Time, I'm up way too late finishing this first post, and I reckon the rest will keep for a few hours at least.

{.wp-image-18972 .size-large aria-describedby="caption-attachment-18972" loading="lazy" attachment-id="18972" permalink="http://svpow.com/2021/05/15/haplocanthosaurus-neural-canals-are-weird-part-1-in-which-we-tell-the-world/wedel-et-al-haplo-neural-canals-fig-4/" orig-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-4.jpg" orig-size="1667,1360" comments-opened="1" image-meta="{"aperture":"0","credit":"","camera":"","caption":"","created_timestamp":"0","copyright":"","focal_length":"0","iso":"0","shutter_speed":"0","title":"","orientation":"0"}" image-title="Wedel et al – Haplo neural canals – fig 4" image-description="" image-caption="" medium-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-4.jpg?w=300" large-file="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-4.jpg?w=1024" width="480" height="392" srcset="https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-4.jpg?w=480 480w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-4.jpg?w=960 960w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-4.jpg?w=150 150w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-4.jpg?w=300 300w, https://svpow.wordpress.com/wp-content/uploads/2021/05/wedel-et-al-haplo-neural-canals-fig-4.jpg?w=768 768w" sizes="(max-width: 480px) 100vw, 480px"}

Anatomical features of the neural canal in birds and other dinosaurs. A. MWC 9698, a mid caudal vertebra of Apatosaurus in posterodorsal view. Arrows highlight probable vascular foramina in the ventral floor of the neural canal. B. LACM 97479, a dorsal vertebra of Rhea americana in left anterolateral view. Arrows highlight pneumatic foramina inside the neural canal. C. A hemisected partial synsacrum of a chicken, Gallus domesticus, obtained from a grocery store. Anterior is to the right. The bracket shows the extent of the dorsal recess for the glycogen body, which only spans four vertebrae. Arrows highlight the transverse grooves in the roof of the neural canal for the lumbosacral organ. D. Sagittal (left) and transverse (right) CT slices through the sacrum of a juvenile ostrich, Struthio camelus. The bracket shows the extent of the lumbosacral expansion of the spinal cord. Indentations in the roof of the neural canal house the lumbosacral organ. In contrast to the chicken, the ostrich has a small glycogen body that does not leave a distinct osteological trace. Yellow arrows show the longitudinal troughs in the ventral floor of the neural canal that house the ventral eminences of the spinal cord. Wedel et al. (2021: fig. 4).

I have a ton of people to thank. John Foster, obviously, for initiating the line of research that led here. Julia McHugh for access to the MWC collections, and for being an excellent sounding board regarding the Morrison Formation, sauropod dinosaurs, and crafting ambitious but tractable research projects. Anne Weil for helping me be methodical in thinking through the logic of the paper, and Mike Taylor for helping me get it polished. Niels Bonde, Steven Jasinski, and David Martill for constructive reviews, which were published alongside the paper. We couldn't take all of their suggestions because of space limitations, but figures 3 and 4 were born because they asked for them, and that's not a small thing. Vicki and London Wedel for putting up with me at various points in this project, especially in the last few days as I've been going bonkers correcting page proofs. And finally, because I'm the one writing this blog post, my coauthors: Jessie Atterholt, Alton Dooley, Saad Farooq, Jeff Macalino, Thierra Nalley, Gary Wisser, and John Yasmer, for their contributions and for their patience during the unusually long gestation of this very short paper.

More to say about all that in the future. For now, yay, new paper. Have fun with it. Here's the link again.

References

Additional details

Description

New paper out today: Wedel, Mathew; Atterholt, Jessie; Dooley, Jr., Alton C.; Farooq, Saad; Macalino, Jeff; Nalley, Thierra K.; Wisser, Gary; and Yasmer, John. 2021. Expanded neural canals in the caudal vertebrae of a specimen of Haplocanthosaurus. Academia Letters, Article 911, 10pp. DOI: 10.20935/AL911 (link) The paper is new, but the findings aren't, particularly.

Identifiers

UUID
09b0593a-ef51-44f6-9e39-4f98ad3c2736
GUID
https://svpow.com/?p=18900
URL
https://svpow.com/2021/05/15/haplocanthosaurus-neural-canals-are-weird-part-1-in-which-we-tell-the-world

Dates

Issued
2021-05-15T09:45:35
Updated
2021-05-18T21:05:29

References

  1. Foster, J.R., and Wedel, M.J. 2014. *Haplocanthosaurus *(Saurischia: Sauropoda) from the lower Morrison Formation (Upper Jurassic) near Snowmass, Colorado. Volumina Jurassica 12(2): 197–210. https://doi.org/10.5604/17313708 .1130144 https://sauroposeidon.files.wordpress.com/2010/04/foster-and-wedel-2014-haplocanthosaurus-from-snowmass-colorado.pdf
  2. Wedel, M. (2021). Expanded neural canals in the caudal vertebrae of a specimen of Haplocanthosaurus. https://www.academia.edu/48922621/Expanded_neural_canals_in_the_caudal_vertebrae_of_a_specimen_of_Haplocanthosaurus https://www.academia.edu/90943314/Expanded_neural_canals_in_the_caudal_vertebrae_of_a_specimen_of_Haplocanthosaurus