I’m scrambling to get everything done before I leave for England and SVPCA this weekend, so no time for a substantive post. Instead, some goodies from old papers I’ve been reading. Explanations will have to come in the comments, if at all.

Streeter (1904: fig. 3). Compare to the next image down, and note that in birds and other reptiles the spinal cord runs the whole length of the vertebral column, in contrast to the situation in mammals.

Streeter (1904: fig. 3). Compare to the next image down, and note that in birds and other reptiles the spinal cord runs the whole length of the vertebral column, in contrast to the situation in mammals.

Nieuwenhuys (1964: fig. 1)

Nieuwenhuys (1964: fig. 1)

Butler and Hodos (1996: fig. 16.27)

Butler and Hodos (1996: fig. 16.27)

For more noodling about nerves, please see:

References

  • Butler, A.B., and Hodos, W. 1996. Comparative Vertebrate Neuroanatomy: Evolution and Adaptation. 514 pp. Wiley–Liss, New York.
  • Nieuwenhuys, R. (1964). Comparative anatomy of the spinal cord. Progress in Brain Research, 11, 1-57.
  • Streeter, G. L. (1904). The structure of the spinal cord of the ostrich. American Journal of Anatomy, 3(1), 1-27.

 

I am just about out of patience with academic departments putting up endless idiot arguments about open access.

Bottom line: we pay you good money out of the public purse to do highly desirable job where you get to work on what you love — jobs that have tens or dozens of candidates for every post. That job is: make new knowledge for the world. Not just for you and a few of your mates: for the world. If you’re not prepared to do that, then get the heck out of the job, and vacate a position for someone who will actually do what we pay them for.

Sheesh. I try to be understanding, I really do. But all this “Oh, oh, it’s not like it used to be in the old days” whining has worn me down. No, it’s not like it was in the old days, when you got paid to play, with nothing expected in return. Earn your damned keep, or get out of the road.

(And, yes, this is a toned down version of the comment I originally composed in my head.)

[Originally posted as a comment at The Guardian.]

Short post today. Go and read this paper: Academic urban legends (Rekdal 2014). It’s open access, and an easy and fascinating read. It unfolds a tale of good intentions gone wrong, a chain of failure, illustrating an important single crucial point of academic behaviour: read what you cite.

References

Rekdal, Ole Bjørn. 2014. Academic urban legends. Social Studies of Science 44(4):638-654. doi: 10.1177/0306312714535679

 

Folks,

You may know that the inaugral TetZooCon is set to take place next Saturday (12 July) at the London Wetland Centre. It’s an informal convention that’s condensed around occasional SV-POW!sketeer Darren Naish’s absurdly informative blog Tetrapod Zoology, and features a day of talks, a palaeoart workshop and a quiz. At £40 for the day, it’s a bit of a bargain.

Among the speakers is my own good self, and I will be talking about why giraffes are rubbish.

Taylor and Wedel 2013a: Figure 3. Necks of long-necked sauropods, to scale. Diplodocus, modified from elements in Hatcher (1901, plate 3), represents a “typical” long-necked sauropod, familiar from many mounted skeletons in museums. Puertasaurus, Sauroposeidon, Mamenchisaurus and Supersaurus modified from Scott Hartman’s reconstructions of Futalognkosaurus, Cedarosaurus, Mamenchisaurus and Supersaurus respectively. Alternating pink and blue bars are one meter in width. Inset shows Fig. 1 to the same scale.

Taylor and Wedel 2013a: Figure 3. Necks of long-necked sauropods, to scale. Diplodocus, modified from elements in Hatcher (1901, plate 3), represents a “typical” long-necked sauropod, familiar from many mounted skeletons in museums. Puertasaurus, Sauroposeidon, Mamenchisaurus and Supersaurus modified from Scott Hartman’s reconstructions of Futalognkosaurus, Cedarosaurus, Mamenchisaurus and Supersaurus respectively. Alternating pink and blue bars are one meter in width. Inset shows Fig. 1 to the same scale.

If that sounds like your idea of a good time, then you need to move fast! Booking closes at 4pm this evening. Better get on it now!

 

We’ve touched on this several times in various posts and comment threads, but it’s worth taking a moment to think in detail about the various published mass estimates for the single specimen BM.R.2181 (formerly known as HMN SII), the paralectotype of Giraffatitan brancai, which is the basis of the awesome mounted skeleton in Berlin.

Here is the table of published estimates from my 2010 sauropod-history paper, augmented with the two more recent estimates extrapolated from limb-bone measurements:

Author and date Method Volume (l) Density (kg/l) Mass (kg)
Janensch (1938) Not specified `40 t’
Colbert (1962) Displacement of sand 86,953 0.9 78,258
Russell et al. (1980) Limb-bone allometry 13,618
Anderson et al. (1985) Limb-bone allometry 29,000
Paul (1988) Displacement of water 36,585 0.861 31,500
Alexander (1989) Weighing in air and water 46,600 1.0 46,600
Gunga et al. (1995) Computer model 74,420 1.0 74,420
Christiansen (1997) Weighing in air and water 41,556 0.9 37,400
Henderson (2004) Computer model 32,398 0.796 25,789
Henderson (2006) Computer model 25,922
Gunga et al. (2008) Computer model 47,600 0.8 38,000
Taylor (2009) Graphic double integration 29,171 0.8 23,337
Campione and Evans (2012) Limb-bone allometry 35,780
Benson et al. (2014) Limb-bone allometry 34,000

(The estimate of Russell et al. (1980) is sometimes reported as 14900 kg. However, they report their estimate only as “14.9 t”; and since they also cite “the generally accepted figure of 85 tons”, which can only be a reference to Colbert (1962)”, we must assume that Russell et al. were using US tons throughout.)

The first thing to notice is that there is no very clear trend through time, either upwards or downwards. Here’s a plot of mass (y-axis) against year of estimate (x-axis):

giraffatitan-mass-by-year

I’ve not even tried to put a regression line through this: the outliers are so extreme they’d render it pretty much useless.

In fact, the lowest and highest estimates differ by a factor of 5.75, which is plainly absurd.

But we can go some way to fixing this by discarding the outliers. We can dump Colbert (1962) and Alexander (1989) as they used overweight toys as their references. We more or less have to dump Russell et al. (1980) simply because it’s impossible to take seriously. (Yes, this is the argument from personal incredulity, and I don’t feel good about it; but as Pual (1988) put it, “so little flesh simply cannot be stretched over the animal’s great frame”.) And we can ignore Gunga et al. (1995) because it used circular conic sections — a bug fixed by Gunga et al. (2008) by using elliptical sections.

With these four unpalatable outliers discarded, our highest and lowest estimates are those of Gunga et al. (2008) at 38,000 kg and Taylor (2009)at 23,337. The former should be taken seriously as it was done using photogrammetrical measurements of the actual skeletal mount. And so should the latter because Hurlburt (1999) showed that GDI is generally the least inaccurate of our mass-estimation techniques. That still gives us a factor of 1.63. That’s the difference between a lightweight 66 kg man and and overweight 108 kg.

Here’s another way of thinking about that 1.63 factor. Assuming two people are the same height, one of them weighing 1.62 times as much as the other means he has to be 1.28 times as wide and deep as the first (1.28^2 = 1.63). Here is a man next to his 1.28-times-as-wide equivalent:

two-men

 

I would call that a very noticeable difference. You wouldn’t expect someone estimating the mass of one of these men to come up with that of the other.

So what’s going on here? I truly don’t know. We are, let’s not forget, dealing with a complete skeletal mount here, one of the very best sauropod specimens in the world, which has been extensively studied for a century. Yet even within the last six years, we’re getting masses that vary by as much as the two dudes above.

 

Vicki with book

Remember how my better half, Dr. Vicki Wedel, edited a book about blunt force trauma, called Broken Bones?

If you live in SoCal and you’d like to get a copy, or get your copy signed, then you’re in luck. Vicki will be one of a dozen local authors signing books at the San Bernardino County Museum this coming Sunday, May 18. There will be books for sale if you don’t yet own the titles you want. Noted paleontologist and skeptic Don Prothero will be giving the keynote address and signing copies of his new book, Reality Check. If you’re in the area, come on by. Details here:

SCBM festival of authors 2014

On Monday we visited the Prehistoric Museum in Price, Utah, the Cleveland-Lloyed dinosaur quarry, and sites in the Mussentuchit member of the Cedar Mountain Formation. Many thanks to Marc Jones for the photos.

1 - CEU Prehistoric Museum

In 2010, the College of Eastern Utah became Utah State University – Eastern, and the CEU Prehistoric Museum in Price is now officially the USU Eastern Prehistoric Museum. The dinosaurs in the center of exhibit hall are being remounted. These include Allosaurus, Stegosaurus, Camptosaurus (mounted, toward top of photo), and Camarasaurus (dismounted, on floor). Most of the mounts are either real material or casts of real material from the nearby Cleveland-Lloyd quarry.

The museum has many other exhibits besides the one shown above. The paleo wing alone covers two floors, and upstairs there are great displays on Cretaceous dinosaurs from the area, including Jurassic and Cretaceous ankylosaurs, a ceratopsian, and numerous tracks.

2 - Cleveland-Lloyd orientation

After leaving Price we went to the Cleveland-Lloyd dinosaur quarry, which has produced over 20,000 separate elements, including the remains of something like 50-60 allosaurs. The smallest ones are hatchlings–several elements from literally cat-sized baby allosaurs are known from the quarry.

3 - Mark Loewen teaching

Mark Loewen (right) talked to us about how the quarry might have formed, and what it’s like to work there. On the left in the above photo you can see a bunch of disarticulated Allosaurus bones suspended above the floor on wires. These are placed to give an idea of the three-dimensional jumbling of the bones in the matrix. It is almost impossible to jacket one bone or even several without hitting others. I remember how that goes from working at the OMNH sauropod bonebed in the Cloverly–it’s almost impossible to avoid blowing through some bones just to get others out of the ground.

4 - Camarasaurus pelvis with bite marks

Here’s one of a handful of bones from the quarry with bite marks. This is the pelvis of a Camarasaurus, lying upside down, anterior toward the wall. The back end of the right ilium is heavily tooth-marked.

After Cleveland-Lloyd we stopped at a couple of sites in the Mussentuchit. I’m not going to blog about those because they are active sites that are still producing fossils. Unfortunately it is not uncommon for fossil localities on public land to be looted and vandalized by unscrupulous private collectors. I don’t want to give those a-holes any help, so I’ve deliberately not shown any photos of about half a dozen of the most interesting sites that we visited during the conference. It sucks to know cool things and not be able to tell people about them, but if I blab then I put those cool things at risk. Happily there is a lot of active research going on, including one or two projects that got hatched at this conference, so hopefully I will be able to tell some of these stories soon.

5 - MMFC14 conveners Jim Rebecca and John

Instead, I will close this series (for now) with a shout-out to the people who convened and ran the field conference: Jim Kirkland (left) and ReBecca Hunt-Foster (middle). John Foster (right) also contributed a lot of time, energy, effort, and expertise.

Jim Kirkland is amazing. If you know him, you know that his heart is as big and outgoing as his booming voice. His knowledge of and enthusiasm for the mid-Mesozoic sites in western Colorado and eastern Utah have driven a lot of science over the past quarter century, and he shared that knowledge and enthusiasm compulsively on this trip. My head is so full of new stuff, it’s honestly hard to think. I wish I had a solid week to just digest everything I learned at the conference.

My highest praise and thanks go to ReBecca. Thanks to her hard work and organization, the whole field conference ran about as much like clockwork as something this complicated can–and when it didn’t run smoothly, like that flat tire on Saturday, she took charge and got us back on track. She was basically den mom to about 60 folks, from teenagers to retirees, from at least ten countries and four continents, and somehow she did it all with unflagging grace and good humor. The fact that she had her appendix out just two or three days before the start of the conference only cements my admiration for what she pulled off here.

I had a fantastic time. I hope they do another one.

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