Get down, get fuzzy, speculative juvenile Apatosaurus!
February 27, 2013
Well, this is rad. And adorable. Brian Switek, whom we adore, commissioned a fuzzy juvenile sauropod from Niroot, whom we adore, for his (Brian’s) upcoming book, My Beloved Brontosaurus, which I am gearing up to adore. And here is the result, which I adore, borrowed with permission from Love in the Time of Chasmosaurs.
There is much to like here. Here’s my rundown:
- Small forefeet that are the correct shape: good. Maybe too small, given that young animals often have big feet. But better too small than too big, given how often people screw this up.
- Pronounced forelimb-hindlimb disparity: win.
- Fat neck: pretty good.
In fact, let me interrupt the flow of praise here to put in Brant Bassam’s dorsal view of his mounted Phil Platt model Apatosaurus skeleton. I’ve been meaning to post about this for a while now and haven’t gotten to it, so now’s a good time: just look at how friggin’ FAT that neck is, and how it blends in with the body, and how the tail gets a lot skinnier a lot quicker (and, yeah, caudofemoralis, but not that much). Now, go look at a bunch of life restorations of Apatosaurus–drawings, paintings, sculptures, toys, whatever–and see how many people get this wrong, by giving Apatosaurus a too-skinny neck. The answer is, damn near everyone.
Apatosaurus lousiae 1/12 scale skeleton in dorsal view, modelled by Phil Platt, assembled and photographed by Brant Bassam. Image courtesy of BrantWorks.com.
Okay, back to Niroot’s baby:
- Proportionally shorter neck and tail because it’s a juvenile: win.
- Neck wrinkles possibly corresponding to vertebrae: okay, just this once.
- Greenish fuzz possibly functioning as camouflage: We-ell…
Yes, it’s true that all of the known sauropod skin impressions show scales, not fuzz. But. We don’t have anything like full-body coverage. And I suspect that there is a collection bias against fuzzy skin impressions. Scaly skin impressions are probably easier to recognize than 3D feathery skin impressions (as opposed to feathers preserved flat as at Liaoning and Solnhofen) because the latter probably just look like wavy patterns on rock, and who is looking for feather impressions when swinging a pickaxe at a sauropod’s back end? And how many sauropods get buried in circumstances delicate enough to preserve dinofuzz anyway? Also, some kind of fuzz is probably primitive for Ornithodira, and scales do not necessarily indicate that feathers were absent because owl legs. So is this speculative? Yes. Is it out of the question? I think not. In the spirit of Mythbusters, I’m calling it ‘plausible’.
Oh, one more thing: Niroot posted this in honor of Brian Switek’s birthday. Happy birthday, Brian! (You owe me a book!)
Off-topic: Get down, get fuzzy, Tianyulong!
March 19, 2009
That clanking sound you just heard was pretty much the entire field of paleontology evolutionary biology wired humanity dropping a solid gold brick: Tianyulong, a basal ornithischian from (where else?) China, has been found with dino-fuzz (Zheng et al. 2009). Not exactly protofeathers, but pretty darn similar. And if they’re in theropods and ornithischians, they were probably primitive for Dinosauria (at least; comparisons of these integumentary structures to pterosaur ‘hair’ are probably coming). It’s certainly possible that the common ancestor of Ornithodira (the pterosaurs+dinosaurs clade, which encompasses most non-croc-line archosaurs) was fuzzy.
(So much for the “fact” that we “know” that small dinosaurs couldn’t have been endotherms because of their naked skin–see, e.g., pretty much everything ever written by Feduccia, Ruben, and the rest of the BANDits [Birds Are Not Dinosaurs cultists]).
The holotype of Tianyulong (Zheng et al. 2009:fig. 1a)
It’s true that we have skin impressions from many dinosaurs that show scaly skin, so if dino-fuzz was primitive for dinosaurs it must have been lost, or had a restricted distribution on the body (like a midline crest), or been ontogenetically transient (possibly present only in babies) in many taxa. If there were any shaggy sauropod skin impressions out there, we’d really, RE-hee-huh-HEEELLY like to know. So far, zip. Even the skin impressions from the Argentinian sauropod embryos show bare, scaly skin (Chiappe et al. 1998).
Still, those skin patches don’t cover the entire embryo. We can’t rule out some fuzz even in the Argentinian embryos, and except for a scrap of bone shard of excellence here and there (Britt and Naylor 1994), sauropod embryos and their skin are otherwise ridiculously unknown to our planet. So we can dream, for a while longer anyway. Back in 1994, Greg Paul drew a hatchling sauropod with dino-fuzz (Paul 1994:fig. 15.3, above), and we’re bringing it back in honor of Tianyulong.
Here’s your obligatory sauropod vert shot for this post. Tremble as the ancient, bloated hulk looms out of the mists of deathless time, like an ageworn stone idol or some eldritch Lovecraftian horror!
Oh, and behind Mike you can just make out the AMNH Brontosaurus (yeah, we know, we’d like to bring that back, too).
UPDATE: MARCH 19
James O’Donoghue wrote a piece for New Scientist on sauropod gigantism, which you can read for free here. He kindly cited my work on air sacs, and even more kindly threw in a link to an SV-POW! post, which I’ll let you find for yourself. Now that I’m sending you there, the hyperlink circle is complete.
Two great things came in the mail yesterday, but those will be subjects of future posts. Stay tuned, true believers!
References
- Britt, B.B., and Naylor, B.G. 1994. An embryonic Camarasaurus (Dinosauria, Sauropoda) from the Upper Jurassic Morrison Formation (Dry Mesa Quarry, Colorado); pp. 256-264 in Carpenter, K., Hirsch K.F., and Horner, J.R. (eds), Dinosaur Eggs and Babies. Cambridge University Press, Cambridge.
- Chiappe, L. M., Coria, R. A., Dingus, L., Jackson, F., Chinsamy, A., and Fox, M. 1998. Sauropod dinosaur embryos from the Late Cretaceous of Patagonia. Nature 396: 258–261.
- Paul, G.S. 1994. Dinosaur reproduction in the fast lane: implications for size, success, and extinction; pp. 244-255 in Carpenter, K., Hirsch K.F., and Horner, J.R. (eds), Dinosaur Eggs and Babies. Cambridge University Press, Cambridge.
- Zheng, X.-T., You, H.-L., Xu, X., and Dong, Z.-M. 2009. An Early Cretaceous heterodontosaurid dinosaur with filamentous integumentary structures. Nature 458:333-336.
Sauropod Vertebra Picture of the Week 