davegodfrey: Coelacanth (Science)
About a month ago John Scannella and Jack Horner published an article "Torosaurus Marsh, 1891, is Triceratops Marsh, 1889 (Ceratopsidae: Chasmosaurinae): synonymy through ontogeny" in the Journal of Paleontology*

*Note. Ceratopsidae are the "horned dinosaurs", including Styracosaurus, Triceratops/Torosaurus, Chasmosaurus, and Pachyrhinosaurus to name but a few. The Chasmosaurines are a subgroup which had long brow horns, short nasal horns, and big frills, (Chasmosaurus and Triceratops/Torosaurus are fairly typical.) The other group (the Centrosaurinae) had short, or absent brow horns, a long nasal horn, and a relatively short frill (Styracosaurus and Pachyrhinosaurus are good examples of this group).

What this paper attempts (and I think succeeds) to show is that the fossils attributed to Triceratops are all juveniles, and the fossils attributed to Torosaurus are all adults. They looked at all the skulls they could get their hands on, and looked at what was happening to the bones, and they are fairly confident that they've identified a growth sequence between Triceratops and Torosaurus.

As it grew Triceratops first developed the long brow horns, and a short solid frill. When it reached maturity then holes in the frill opened as bone was absorbed, and the frill itself then grew significantly longer. There are one or two Triceratops specimens that show that the bones in the frill were starting to thin as this happened.

So all in all, a reasonably convincing study. So why the hoo-ha?

Because journalists (and the sub-editors responsible for their headlines) can't read, and then the internet gets hold of their shoddy penmanship, and before you know it people are clutching their pearls and comparing this to "Pluto not being a planet anymore". (Breaking Daily News are particularly precious, I really can't see how this could delight creationists at all.)

Anyway. The ICZN (International Commission of Zoological Nomenclature) has some pretty strict rules about how you go about naming things. Generally the first name given has priority. Its why Brontosaurus was renamed Apatosaurus (Apatosaurus was published first). Its why Laelaps had to be renamed Dryptosaurus (a mite had already been given the name). Its generally a very sensible rule, and only causes problems when you discover that another name was previously published for the same species, but completely ignored, or if the type species, or the specimen on which the name was originally based turn out to be fairly poor for identifying, well anything.

When this happens you appeal to the ICZN and they think about it, ask for comments and make a decision. Often they'll agree with you. If no-one's used a name for ages there's no point in keeping it if everyone else uses something different. There's a application currently going through the ICZN< to replace Cetiosaurus medius with Cetiosaurus oxoniensis as the type species of the sauropod Cetiosaurus, primarily because the material of C. medius is crap, and everyone uses C. oxoniensis when talking about Cetiosaurus. Something similar happened to Iguanodon a little while ago, and there was a paper recently that made everything really confusing. Some day I'll write about it.

Anyway, in this case strict priority is going to rule. Torosaurus was described three years after Triceratops. The species included in Torosaurus will be reclassified as species of Triceratops. Scannella and Horner don't go so far as to synonymise the individual species however, so Triceratops gets several new species and a new look for the adults.
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davegodfrey: Coelacanth (Science)
So  having had a look at the paper, and watched the video courtesy of Nature I thought I'd see how the various newspapers reported this new and interesting discovery.

As far as I can see The Daily Express doesn't cover it at all. But as their astrologer is writing a guide to getting fit in 2010 I think they might have given up on being a newspaper these days.

The Mail throws the "Missing Link" phrase around in the first paragraph. Which is a shame, because I've not seen it mentioned anywhere in the reporting or the press release. If anything this is something that would have been largely ignored if it was contemporaneous with the body fossils- "Oh neat, tetrapod trackways. Oh they're marine. That's interesting, virtually everything else is freshwater" would have been the response. However the rest of the article is not bad- the quote from Ahlberg reads like the abstract, and they've lifted some quotes from Phillipe Janvier's "News and Views" article accompanying the Nature paper. I think they fumbled it a bit, but made a decent recovery. Just don't look at the comments.

The Guardian is pretty good actually. Doesn't use the "missing link" phrase, which I think is a win. Quotes Janvier (who made the important point that the sequence of fossils probably hasn't changed, its just that the timing of the actual transition is way off). It also quotes Ahlberg and Jenny Clack (though it initially spelt her name wrong- but this is the Guardian, so that's to be expected). Where I think it does best is online, where there's the blog by Adam Rutherford providing more information I mentioned last time.

The Indy is generally very good, and provides more information about the circumstances leading up to the find- they were thought to be dinosaurs until they had another look at the fossils in the surrounding rocks to work out how old they really were. It probably explains why the article says "They occurred in a rock formation several metres beneath a younger rock formation." because otherwise that's a totally pointless statement- there's no information about why this younger formation is important. Did it contain the conodonts that they used to work out how old the rocks were? Was it just a pretty colour? What? Enquiring minds wish to know.

The Times however seems to be making stuff up. It describes the creature that made the tracks as looking like a stout crocodile, which is not an inaccurate description of the typical early tetrapod. However it says that; "However, unlike the modern-day crocodile, the ancient creature appears to have held its body up from the ground as there is no trace of it being dragged along. It may have been closer to a dog in terms of posture." No. Seriously. Just No. Crocs have legs that stick out from the side less than that of lizards or salamanders, giving them a semi-erect gait that raises their bodies off the ground. Dogs have a very different gait, their legs are directly under their bodies like dinosaurs, and mammals. All the early tetrapods have sprawling gaits- we don't see body or tail trails because the animal was supported by water in the intertidal zone, and because it had a sacrum which allowed it to support its tail with the hind limbs. Dogs don't enter into this anywhere.

Its also not true that the rocks "teemed with marine fossils". Tracks are common, but body fossils are extremely rare, and this is not uncommon. There seems to be something about environments that are good for preserving tracks, but lousy for preserving the organisms that made them. I think however they may have redeemed themselves by solving the question of why they were thought to be dinosaur tracks- the man who first discovered them didn't know how old the rocks were.

The red-tops seem to have completely ignored it, which is not surprising- Metro gave it a sentence or two, and I can't find it on the intertubes.

So not a bad showing for the papers this time round. Shame the creationists turn up with their "how can you know so much from a footprint?" crap. Well dear, lots. There's a whole science out there that you're completely ignorant of called ichnology.
davegodfrey: Coelacanth (Science)
The entire world seems to have gone utterly insane over this fossil, known colloquially as "Ida", but officially as Darwinius masillae. And it is a lovely fossil. It is also important because it will, I'm sure, tell us lots about what was going on in primate evolution 47 million years ago. I'm not going to go through the reports because there are too bloody many of them, but I will point out that while many have fallen for the "Missing Link" Found! angle plenty of others- especially the bloggers writing opinion pieces are being rather more restrained.

However utterly revolutionary it is not. At best it means a group of animals a bit like lemurs (Adapids) are more closely related to apes and monkeys than a group of animals a bit like Tarsiers (Omomyids). Be honest had you heard of either?

I quite like it because its another species published in PLoSOne (The Public Library of Science). This is an open access journal, so anyone can download and read a copy of the paper for free. There's a lovely long description of the fossil- it is young (under a year old), female (it lacks a baculum [penis bone] which you'd expect to see in male primates like this), and very nicely preserved (the body outline, hair and stomach contents are all preserved).

Its from the Messel deposits, which have yielded beautiful fossils of fishes, early horses, ants, weird mammals like Leptictidium, and all sorts of other things. Messel was covered in one episode of David Attenborough's 1980s series on fossils Lost Worlds, Vanished Lives, and also in the first episode of Walking With Beasts- though proto-whales aren't known from the area. I can't believe someone thought it was a good idea to turn the site into a rubbish dump. Fortunately they haven't, and it is now a World Heritage Site.

I am not qualified to say how much this fossil supports the conclusions that the authors are trying to draw- that the group to which Ida belongs are more closely related to monkeys and apes than tarsiers and their relatives are.  However the paper lacks a phylogenetic analysis and as Laelaps and The Open Source Paleontologist points out this is something one expects to see when claims for moving large groups around are made. Hopefully one will be done soon, and the question of whether Adapids (the group to which Darwinius belongs) is closer to lemurs or monkeys and apes will be better resolved.

I don't really have much to add to the criticism of the hype either. Both Ed Yong and Carl Zimmer have covered it far better than I could hope to. Especially Ed's post.

Personally the part that really annoys me- I wouldn't be at all surprised if the view of the Adapids in the paper turned out to be wrong. You just know that the creationists will have a field day because while I'm sure most of you know that the great strength of science is that whenever new information appears which contradicts its conclusions we change our minds- something the creationists seem incapable of appreciating as being A Good Thing. I just hope I am pleasantly surprised.
davegodfrey: South Park Me. (Default)
Mark Witton (who as well as being a pterosaur bod is a fabulous artist- seriously check out the flickr set) has identified a new genus and species of pterosaur. This time its published in Palaeontology, so unlike last time not everyone can go and read the paper for free. Fortunately Mark blogs as well as publishes his art on the flickr site. (The article in question is here, together with the images used to publicise the paper in the press). Go read it, its a very interesting article on some of the problems encountered when working with specimens.

As with his joint paper with Darren Naish on Azdarchids its made the national press in several papers. Luscovagus magnificens ("Magnificent Lake Wanderer") comes from the Crato Formation in Brazil, belongs to a group of pterosaurs called the azdarchids (along with the more famous Quetzalcoatlus), specifically a group called chaoyangopterids. A recognisable (but not unique) character is that azdarchids don't have teeth.
The University of Portsmouth's press release about this find says "The finding is significant because it originated in Brazil and is the only example of the Chaoyangopteridae, a group of toothless pterosaurs, to be found outside China and is the largest one ever discovered." This sentence may become important later.

The Independant has an nice article, describing how the specimen had been lurking in a museum drawer in Germany (as so many are), that it was preserved in manner that was awkward to interpret, and that we don't have much of it, so we need more specimens, but that because its a long way from China it demonstrates nicely how much we don't know about these animals. A third of the article is quoted directly from Mark, and its a rather nice article. No glaring errors, nice big images through a link, well done Indy.

The Daily Mail thinks there's a team involved. (Well, there would be several people doing the CT scanning, but only Witton's name is on the paper). Other than that pretty much everything's the same as the Indy article, quotes from Witton, etc. The website shows both illustrations- I do like the scale silhouette of Witton scratching its chin.

This time aroud its the Guardian that fails miserably. "Giant Flying Reptile- Terror of Cretaceous Skies" proclaims the headline. "Lacusovagus magnificens, the magnificent lake wanderer, is the largest prehistoric flying reptile without teeth ever to have been found." The article goes on to say that though its big its dwarfed by some of the toothed pterosaurs, quoting Quetzalcoatlus and Hatzegopteryx as being much bigger. Unfortunately those species are both toothless. as are all the azdarchids I'm aware of. Pteranodon was also toothless, (as the name suggests), and had a wingspan of about 7-8m and has been known since the 1880s. If you have links to the paper describing Hatzegopteryx you'd think you might do a bit more basic fact checking. But no.

Can it get worse? You bet.

The beeb?, Virtually identical to the Indy. Both the Telegraph and The News in Portsmouth call it a dinosaur, which is a glaring error, but otherwise get everything right.

And now the Metro. I think you know what to expect. The article is only five sentences long, including the headline. The headline calls it a dinosaur. It then states that it is the first toothless pterosaur found outside China. Now unless they got the name of the animal, where it was found, or how big a "family car" is they couldn't have fitted more errors in the article.

I therefore have one request to make of Metro. If you can't even read a press release, please stop reporting science. You wouldn't tolerate this if you were reporting on football. You wouldn't be allowed to.

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davegodfrey: South Park Me. (Default)
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