Archive for October, 2010

Megalosaurus

So here it is then, the dinosaur. It’s long overdue given how long ago I covered the Pterodactylus holotype, so it is about time I put up a post on Megalosaurus, the first dinosaur. Here is that original jaw that in hindsight looks so obviously theropodan but of course caused consternation when it first appeared.

Darren Tanke’s Gorgosaurus preparation 2: into the jacket

Bringing in the jacket

The Gorgosaurus block was brought in the main preparation lab of the Royal Tyrrell Museum today. Its catalogue number is TMP 2009.012.0014. I should explain the numbering system as some don’t understand how it works. TMP = Tyrrell Museum . 2009 = year of collection. 012 = site, in this case a general number for Dinosaur Provincial Park . 14= 14th specimen. So translated this Gorgosaurus is the 14th specimen collected from Dinosaur Provincial Park , in 2009 by the Royal Tyrrell Museum.

All the catalogue data were on the part of the plaster and burlap field jacket which was going to be removed, so I transferred that data to the side of the jacket, rewriting it with a black magic marker. Don’t want to lose that number! Sometimes I will consult catalogue records if I am preparing a specimen unfamiliar to me. Perhaps the collector noted something about the specimen that I cannot see, such as how a certain area is poorly preserved and broken up. Forewarned I can be especially careful when I am digging down to this area. However, as a co-collector of this specimen I know all its little idiosyncrasies so could bypass that step.

The first incision

Then I got ready to open the jacket. Cutting plaster makes a lot of dust so I sprinkled some material (oily sand and sawdust) onto the floor to keep dust levels down and confined so I was not tracking plaster dust all over the museum later on. I got a dust extractor (essentially a giant vacuum cleaner that filters the air) ready to suck up the dust created while cutting. I got a cast cutter- a piece of medical equipment used to cut casts off of broken arms, etc. The blade of this does not spin but rotates back and forth about 5 degrees. As I had only made two plaster/burlap layers on this side of the jacket (to lighten it for the helicopter lift), the cast cutter did quick work- I cut all the way around on the edges in about 10 minutes. I then got some flat screwdrivers, inserted the blade of one into the cut I just made and started to pry up the jacket, moving along, prying and holding up in a stepwise fashion. Within 10 minutes the whole piece popped off. I then vacuumed the dust from the edge of the jacket and threw the cap piece away.

Darren at work with the cutter

The cap is ready to go

The rock had dried out inside the jacket and shrank, forming some deep cracks. This is a common occurrence. I mixed up some dental plaster to the consistency of milk and poured that into the cracks until they filled up. The plaster adds stability to the crack and can be removed as required. More plaster may be added as I work my way down into the rock. The bowl we mix the plaster in is made of rubber- it is easy to clean out, you just wait for the remnants of plaster to harden then you squeeze the bowl and all the plaster breaks free. Most of the rock showing in the jacket now is clay. That I can remove without delay as the specimen itself is inside the white sandstone immediately underneath.

Inside the jacket

Adding some plaster

More to come soon! All photos here and in the series are owned by Darren Tanke and the Royal Tyrrell Museum.

Updates on Pterosaur.net

We always promised that there would be some updates and upgrades to come on the Pterosaur.net mainpage. Mike Habib has recently been tweaking his section on take-off and flight to include his own recent work and keeping things on track. Head over (if you haven’t already) and catch up with the updates. (And don’t you dare forget the blog!).

And while I’m on the subject, I’m delighted to see that P.net is the number three return for a google search of ‘Pterosaurs’, it’s just a shame that number four is a site advertising the existence of modern pterosaurs. Something about which I have my doubts…

Pathologies

Animals, somewhat inevitably, get ill. (As a minor aside, this is one of the great fallacies about life in the wild that animals live in some kind of paradise where everything lives free and happy and never gets eaten alive by a predator, or starves to death, or gets and infected wound and disintegrates from gangrene for example. Anyway, while of course most illnesses only affect soft tissues, some diseases and infections will leave a mark on the bones themselves and obviously as a palaeontologist these do turn up in the fossil record.

There are all kinds out there (I’ve mentioned one on a Mamenchisaurus before) but of course it is useful to see these things in modern animals to see what effects cause which pathologies and then try to track them on the fossils. There are fossils (including dinosaurs) diagnosed with arthritis, cancers and pathologies resulting from infected injuries. In this case, this is the jaw of a hippo which has clearly had something go quite wrong (though what I’m not sure, though my guess is a nasty infection). The bone is swollen and pitted at the base of the tooth is actually visible – this is clearly not natural and looks very different to the other side of the jaw. These kinds of thing at least can give you an idea if the feature you are looking at is a weird bit of anatomy or the result of a pathology – it’s not always easy to tell.

Darren Tanke’s Gorgosaurus preparation 1: getting started

Darren Tanke with Gorogsaurus life model

So it’s time to get started on the great Gorgosaurus preparation job. To get us started and introduce the work Darren Tanke has answered a few questions about the project:

Continue reading ‘Darren Tanke’s Gorgosaurus preparation 1: getting started’

Platypus eggs

OK so it’s not even close to being an archosaur, but these are too cool not to do a post about. Yet another specimen from the Oxford Museum, these are a set of eggs from a platypus. It is one thing to intellectually know that a species does something, but it is always nice to see that evidence in the flesh (or in the egg). I was genuinely excited to see these and since I’m currently lecturing about mammalian reproductive systems, it seemed too good an opportunity to miss not to post this up.

Neomorphs

A bit of terminology this time out – neomorphs. The name suggests that these have a new shape, but while that’s true somewhat by default, the term is generally used to describe new bones. These are new in the sense that they are novel structures that have arisen in an evolutionary lineage. Given that my target audience on the Musings is one with a degree of biological / palaeontological knowledge, I’ll brush right over what homology is in these parentheses (homology being the idea that the humerus in say, a human, is the same bone [in terms of evolutionary inheritance] as the humerus in a bat, and a dinosaur and a bird and so on) and move onto what this means in terms of homology.

Obviously not all animals have exactly the same skeletons. Variation aside, for a start things can be modified (hence bats can have much longer fingers than say humans). Bones can fuse together to form apparently new or highly modified structures (like clavicles fusing to form a furcula). Bones can be lost too (which is why modern horses have only one functional toe, but their ancestors three and their ancestors five). But bones can also be *gained* and these are the neomorphs.

In archosaurs at least, these turn up quite regularly. Pterosaurs have that unique wrist bone – the pteroid that supports (in some way) the propatagium, and the prepubes that sit, well in front of the pubes. Ornithischian dinosaurs have two – the predentary that makes up the front of the lower jaw and the palpebral that sits over the orbit. Ceratopsians, perhaps unsurprisinglty have a few more of their own with the epoccipitals and epijugal making part of their horns and frills.

One could also argue that the numerous repeatedly novel osteoderms that appear in stegosaurs, crocs, saltasaurs and others are all neomorphs too, and arguably the ossified tendons of the ornithischians. In a sense of course they are, but since we don’t give names to all those little bits, listing them all seems a bit frivolous. The terminology is as ever, a slave to us and not a master, and the term ‘neomorph’ is there as a convenience for us to use as appropriate. So while there is inevitably quite a bit of grey to its exact definition and usage, it’s still a handy term to have around to describe those novel elements that turn up.

Just some links

Yes it’s lazy post time again but these have been building up and I felt I should get it done. For those who have not realised, Juila Heathcote has moved her blog for ‘The Ethical Palaeontologist’ to a new location ‘Stages of Succession‘. Larry Witmer and his lab have started a blog called ‘Pick and Scalpel’ to cover their work and can be found here. last but not least, I’d urge you to check out Victoria Arbour’s palaeo blog about her tips to Russia, and large chunks of Asia. I really hope she keeps going though to make a solid and long-term palaeo blog. Now trip over to Pseudoplocephalus to check it out.

Oh yes, and following his successful interview here, Jeff Martz has started colouring in his dinosauromorphs. Groovy!

Darren Tanke and Gorgosaurus

So as you should now know, coming up is a series of posts from Darren Tanke as he prepares his way through a new Gorgosaurus specimen. This is really cool as this is, naturally, the first time this specimen will be unveiled as it were – you’ll get to see something new as it happens. It seemed appropriate at the start to give a bit of an introduction to Darren, and indeed to the dinosaur he’ll be working on.

Darren works at the legendary Royal Tyrell Museum in Drumheller, Canada which is heaving with local Late Cretaceous dinosaurs and other taxa. He’s been there over thirty years now making him the longest serving employee there (perhaps unsurprisingly). His formal job, as it were, is that of a preparator – preparing the rock from the bones of fossils and repairing and restoring them for study and display. However, Darren’s work goes well beyond this and he is known and respected as a researcher in his own right with dozens of papers to his credit (see his Academia.edu page or check out his Wikipedia entry, and yes, he has one of them too!).

Darren has carried out fieldwork all over the world and is particularly well know for finding lost quarries. Sadly many researchers in the early days were not always great at marking out where their specimens came from and Darren has made it a special task of his. He’s also done a lot of work on the history of palaeontology with papers on the history of important specimens or researchers.

For those who don’t realise, this is seriously impressive. While many preparators do contribute to research papers thanks to their work and knowledge there are not so many out there that have published more than a handful of papers, and especially not as a regular lead author. I’m delighted to have him contribute on here with both hats on as a researcher and preparator.

Moving onto Gorgosaurus, while not famous itself, and therefore perhaps unfamiliar, its cousin Tyrannosaurs certainly should be.  Yes Gorgosaurus is one of the giant tyrannosaurs and while a little smaller than rexy is hardly unimpressive – around 8 m or so long and at least a couple of tons in mass at adult, this is not a small carnivore. It is a classic tyrannosaur with a large head, robust teeth, small arms and the rest. If you don’t already have a good idea of what to expect then take a look at this post showing a juvenile prepared by you know who. It dates from the Campanian in the Late Cretaceous (so that’s about 75 million years ago) and lived alongside another large tyrannosaur – Daspletosaurus.

As for the upcoming project believe it or not I have no idea what Darren has lined up for us. All he has told me is that it is a nice specimen and shouldn’t take too long to prepare. I simply haven’t asked and have yet to see a photo of it or anything, so I’m genuinely excited to see what is coming. Above is a photo of the excavation, but obviously it doesn’t reveal that much (photo from the Tyrell’s Facebook page here) though Darren has revealed that it had to be taken out by helicopter so it’s clearly not going to be a small one.

Just as a final bit of housekeeping, while Darren will be writing these posts, I’ll be filing them under the ‘practical palaeontology’ banner rather than ‘guest posts’ as it should make them easier to find for more people. Tune in shortly when we’ll kick off and Darren will reveal the specimen for the first time and tell us what his plans are for it.

Special Guest Post series coming soon

The guest posts on the Musings are generally very popular, indeed I’m often a bit peeved that more people seem to want to read other people’s work on here than mine. No matter, it’s great to have different voices on here and ones that fill in the gaps that I’m unwilling or unable to blog about.

I do bug people from time to time when I know something interesting is coming up and most people are very generous with their time. One of these is preparator and researcher Darren Tanke who is likely familiar to many on here. Some time ago I asked Darren if he might be interested in writing about a Gorgosaurus specimen he was preparing. Sadly he was too busy, though he was most generous with images of the fantastic specimen. However, Darren did have another idea and that is finally coming to pass.

Thanks to the generosity of the Royal Tyrell Museum where he works, Darren is going to be giving us a blow by blow account (with photos) of preparation on another Gorgosaurus. Stick with us for the next few weeks and Darren will be showing the progress made on this tyrannosaur and talking about the techniques used. I am, naturally, extremely excited about this project and very grateful to both Darren and the Tyrell. I’ve never covered the skills and techniques of preparing fossils in the depth I’d like and that is about to be corrected in a very special way.

Stay tuned!

The importance of words

On of the most popular posts on the Musings is that where I expounded about the importance of a general scientific education for kids as a general tool in life. Aside from the actual scientific content (what is an atom, why does the Earth rotate, what mammals are, why it rains etc.) the actual part of critical thinking and assessing evidence on its merits is incredibly useful. Since my return to the English speaking part of Europe I have been staggered and irritated in equal measure by the sheer weight of weasel words in advertising things. I’m not sure if I’m more irritated that advertisers think this will work, or the fact that it probably does. In a fully rational world, no one would buy this stuff.

I recently saw a TV add for yet another anti-wrinkle cream which claims it was ‘inspired by the science of genes’. Now for starters this is meaningless, ‘genes’ are things, not a science. You cannot be inspired by the science of rocks. It’s called geology. Gene therapy, genetics, gene technology yes, but genes? No. In any case, and more importantly, this is such a transparent attempt at sounding scientific and include a nice important sounding buzzword. I could be inspired by the science of genes to draw a small picture of the moon but it would not actually require DNA, a lab, primers, electrorphoresis, or anything like genetic research at all to actually do. Which is the case here as soon as you see the product.

Words are important and spotting when words are being used to imply something which they do not actually say is useful. Most advertisers would be out of a job in seconds if they were not able to use things like ‘people say’, ‘it is thought’, ‘many suggest’ and ‘it’s well known’ when what they want you to think – but can’t say – is that ‘this is true’. And presumably they can’t say it because it’s not true, so they have to hint and suggest and imply. Only the other day I say a piece of rock salt advertised as being good for asthma because of it’s alleged properties at ionising the air. This is, I strongly suspect nonsense, not just because it sounds like rubbish but because the most convincing ‘evidence’ they could get on their note was that ‘some people say that’. Some people say? That’s all it takes for people to transpose this into their head as ‘X does Y’? Wow.

Think about words, think about their real meaning and how they are being used and don’t misinterpret them. And don’t fall for the traps that are being set by people who want you to misinterpret them. And do make sure that what you write means what you want it to mean.

Archaeopteryx

I have only a few of my childhood dinosaur and biology books still in my possession and those are sitting in a box somewhere in my parents’ house. However, I remember this model Archaeopteryx from Oxford gracing at least one of them. While I do like life reconstructions in museums, it seems almost everyone has an Archaeopteryx – I’ve certainly seen quite a few of them, I assume since they are relatively small and certainly famous it’s a suitable subject (few places can’t afford to do one or find space for it, when few can consider making a life size Stegosaurus or Brachiosaurus to be practical). Still this one is likely more famous than many and I was pleased to be able to reminisce on seeing it. I suspect a few others will remember it.


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