BrontomerusRoughWeb From field correspondent Brian Engh:

A Brontomerus on the edge of a jumbled forest of partially knocked over trees. While I won’t be finishing this particular drawing I decided I want to develop this idea a bit further – I think it would be cool to show a group of brontomeri rearing and grazing on the edge of a forest where a lot of the trees are leaning and show signs of heavy grazing, particularly by giants who rear up, bear hug them and rip down their branches. I’m talking tore-up bark around hand-claw height, trees that are growing bent, but then straighten up above max-bronto height, and maybe a constellation of camptosaurs and pterosaurs living around the brontos for food and protection… anyway, just an idea. Any thoughts?

Yeah. I judge it rad. And plausible. I love the heavy texturing on Bronto and the way the background is simple and evocative at the same time. I like the idea of a forest modified by sauropods for their use. I would like to see more plants damaged by sauropods (but still surviving)–and vice versa. For the proposed full version, the camptosaurs will have to be replaced by tenontosaurs, this being the Early Cretaceous. But they’re both ornithopods, so probably no one will know or care.

Anyway, I’m pretty sure Brian wants genuine feedback, and not just predictable gushing from yours truly. The comment field is open.

Bonus Engh sketch: a rearing Miragaia. Rearing Miragaia by Brian Engh

New hotness out today: Miragaia, a new long-necked stegosaur from the Late Jurassic of Portugal (Mateus et al. 2009). What is “long-necked” for a stegosaur? In this case, well over a meter! That may not sound too impressive for those of you who have gotten complacent about 10-meter-plus sauropod necks, but it’s a big deal. Miragaia is described as a sauropod mimic, and with good reason: its body proportions are not that different than those of a basal sauropod.

The number of ways to increase the proportional length of the neck are limited: you can add cervicals, or recruit dorsals into the neck, or make the individual vertebrae longer, or do some combination of  the above. In sauropods, different clades took different routes. Brachiosaurids kept a fairly primitive cervical count of  13 but made the individual vertebrae crazy long. Diplodocids recruited dorsals into the neck, and some (like Barosaurus and Supersaurus) also made the vertebrae crazy long. Mamenchisaurids and Euhelopus added cervicals (independently), up to a total of 17 or more, and some (like Omeisaurus)–are you ready for it?–also made the vertebrae crazy long.

In general, stegosaurs took an evolutionary walk through Door Number 2: turning dorsals into cervicals. Mateus et al. (2009) show this nicely in a table; the number of presacrals (cervicals plus dorsals) in stegosaurs stays about the same, between 25 and 27, but between the basal Huayangosaurus and the derived Stegosaurus 3 or 4 dorsals go forward to play for the other team. Is dorsal recruitment sufficient to explain the long neck of Miragaia? Hard to say, since the dorsal series has not been found. But Miragaia‘s count of 17 cervicals is significantly more than Stegosaurus‘s 13. If Miragaia didn’t add any cervicals but only recruited dorsals, it would have had only 9 of the latter. That’s not impossible–Barosaurus did that very thing–but it’s weird, and extreme. As Mateus et al. (2009:p. 4) state, “Miragaia possessed more cervical vertebrae than any other non-avian archosaur, except the Chinese sauropods Mamenchisaurus, Omeisaurus and Euhelopus, also with 17″. And yet the individual vertebrae are pretty short, no longer than in your not-exactly-average Stegosaurus.


I couldn’t resist pitting Miragaia, the longest-necked stegosaur (so far!) against Brachytrachelopan, the shortest-necked sauropod (so far!). Miragaia is stolen from Mateus et al. (2009:fig. 1a), and Brachytrachelopan from Rauhut et al. (2005:fig. 1a). Both critters come with the 1 meter scale bars from their respective figures. I’m in there for scale, too, at 6’2″ or 1.88 meters. Sauroposeidon looms in the background, just to keep things in perspective. The entire neck of Miragaia might have been about as long as one of the middle cervicals of Sauroposeidon or Supersaurus.

Still, you know.

Not bad.

(for a stinkin’ ornithischian)

A couple more pictures here.