Comments on: A Light, Quick, Killing Machine

By: New Commentary Stirs Dino-Bird Brouhaha | Dinosaur Tracking

New Commentary Stirs Dino-Bird Brouhaha | Dinosaur Tracking — Tue, 16 Feb 2010 15:05:50 +0000

[...] descendants of dinosaurs. Over the past ten years a flood of fossil evidence, from evidence of bird-like breathing apparatus to remnants of pigments in preserved feathers, has confirmed beyond a reasonable doubt that birds [...]

By: The Allosaurs Make a Comeback | Dinosaur Tracking

The Allosaurs Make a Comeback | Dinosaur Tracking — Tue, 20 Oct 2009 14:14:32 +0000

[...] from Cretaceous rocks outside North America. A number of these, such as the recently described Aerosteon , closely resembled Allosaurus. And Aerosteon was not alone. The authors of the new study have [...]

By: Dinosaur Tracking

Dinosaur Tracking — Thu, 06 Nov 2008 16:04:17 +0000

[...] weeks ago I wrote about a newly-announced predatory dinosaur named Aerosteon, described in the open-access journal PLoS. For years, the scuttlebutt among paleontologists was [...]

By: Laelaps

Laelaps — Thu, 16 Oct 2008 18:29:40 +0000

Ed; The concept of ghost lineages was precisely what I was hinting at with that question.

Aerosteon was an allosauroid, but it appears to be closer to the North American Allosaurus (an allosaurid) than the carcharodontosaurids from South America and Africa (which also fall into the larger grouping of the allosauroids).

The question is, then, when did the lineage represented by Aerosteon move into South America? As you say, it implies there is a ghost lineage, but the question I raised remains open.

By: Ed Pardo

Ed Pardo — Thu, 16 Oct 2008 17:25:44 +0000

Re: “How did a relative of a North American dinosaur make it to South America and persist there for so long?”
Eurasia, Africa, South America and North America all had related species. Just because one fossil has a date that raises questions does not mean that siimilar older animals did not exist when the continents were all connected. The similarities simply point to a ghost lineage.

By: Hugh

Hugh — Thu, 16 Oct 2008 17:16:32 +0000

There’s a bit more on Aerosteon over at our sister blog, the Gist: http://thegist.smithsonianmag.com/archives/436 – but thanks to Brian for the fascinating detailed version.