Science and punk rock brought to you by Bad Religion.

You've got to quit your little charade and join the freak parade
Now that your road has been paved from conception to your grave.
Enormous things to do, others' practices to eschew,
To be better than you is impossible to do,

But the world won't stop without you.
No, the world won't stop without you.

Your achievements are unsurpassed, you are highly-ordered mass,
But you can bet your ass your free energy will dissipate.
Two billion years thus far, now mister here you are,
An element in a sea of enthalpic organic compounds.

The world won't stop without you.
The world won't stop without you.

You're only as elegant as your actions let you be
A piece of chaos related phylogenetically
To every living organ system, we're siblings, don't you see?
The earth rotates and will revolve without you constantly.
Two billion years thus far, now mister here you are,
An element in a sea of enthalpic organic compounds.

The world won't stop without you.
No, the world won't stop without you.
I said the world won't stop without you.

****

Some relatively personal thoughts on the convergence of punk rock and science and what they both my mean within the confines of my own life are coming within a few days for any of those interested.

The Paleo paper Challenge.--

Andy Farke and Dave Hone are putting together a project called the (you guessed it!) Paleo Paper Challenge. The idea? Finish a paper and get it published by the beginning of next year. It's especially a new (and thus far quite interesting) challenge for me because I've never before attempted a formal scientific publication--until now I've strictly dealt with translating the information I've been learning (my interest in paleontology, especially as a life's path, was rekindled by a chance event last spring) into a medium aimed for the curious layperson.

Basically, the paper is a review on a group of ancient prehistoric animals called the Spinosauridae (I've blogged about Spinosaurus here before, so you shouldn't be entirely unfamiliar!). From the first discoveries through the century following, it details a multitude (and a half) of finds that have been made by paleontologists spanning the globe and adds my own thoughts and interpretations behind them--their form, evolution, and biotic history.

So, give it a chance! Even if you've never tried it before, there's no better time to start than now.

-Tor

Eocarcharia.

The Carcharodontosauridae, a group of enigmatic and titanic theropod dinosaurs (whose members included Giganotosaurus and Mapusaurus, amongst others) were one of the most successful predatory dinosaurian clades of all time. While the Tyrannosaurids dominated the niche of large predator in the northern hemisphere throughout the Cretaceous (the last of the three major periods of the non-avian dinosaurs' existence; lasting 145.5-65.5 million years ago), the Carcharodontosaurids, Abelisaurids, and Spinosaurids formed a frequently found biological triumverate in the Southern hemisphere; creating a fascinating and as it would appear, alarmingly successful example of a phenomenon called niche partitioning, in which multiple animals of similar (in this case massive) body size can operate in the same ecosystem with minimal to no competition by utilizing different niches (one of the most important aspects of which includes a differential food source). One of these Carcharodontosaurids, Eocarcharia dinops ('Fierce-Eyed Dawn Shark'), is the subject of this blog.. Eocarcharia, discovered in the western Ténéré Desert of Niger by paleontologist Paul Sereno and his field crew based out of the University of Chicago, is a remarkable animal. As one of the most basal members (those that display many early evolutionary characteristics of an individual group--much like the Platypus represents the basal, egg-laying mammalian condition) of the Carcharodontosauridae, it embodies a fantastic image of the early (but not earliest) development of the traits we associate with the group.

One of the most distinctive of these traits has to do with several bones of the skull--the orbit, the lacrimal, and the frontals. Archosaurs (like the crocodilians and the only living clade of dinosaurs, the birds) are partly characterized by a large opening in the skull called the Antorbital Fenestra (the first hole just behind the nares, or 'nose holes' ;-) , though the fenestra does not exist in living crocodilians). The two bones that border the eye socket, or the orbit (the large opening behind the Antorbital Fenestra) are the Lacrimal and the Postorbital-- from the front and back of the orbit respectively, each of which are attached to the frontals, a pair of bones on the top of the skull.

In late Carcharodontosaurids, these two bones meet together to form a greatly enlarged shelf that separates the frontals from the orbit region entirely (in many other dinosaurs, the frontals aren't excluded!). As hypothesized by Sereno, it's very possible that this evolution of a thickened 'brow' above the eyes to that degree suggests an adaptation for lateral impacts--sideways headbutting Carcharodontosaurs! (though I should note that a similar, but much less prominent brow is found in some Abelisaurids and Tyrannosaurids, suggesting that the development of the feature is partly related to reaching large body and skull size)

As you can see from the above diagram (below the Carcharodontosaurus skull), the frontals of Eocarcharia are separated from the orbit, but only by a small degree--though the Lacrimal of the animal itself wasn't found, Sereno and crew were able to determine its basic shape and size by the way it articulates or attaches to the post orbital and frontal. 50 million years later, this brow-like condition was greatly developed and enhanced in its relatives. Though there are many other features of note, one thing that really strikes me as fantastic about Eocarcharia is its teeth--as much as it is easily referable as a Carcharodontosaurid, the distinctive teeth of later ('derived') Carcharodontosaurs have serrations that stretch from the base of the tooth to the tip and back up the front to the base once more (thus giving the clade its name--a similar pattern is found in many modern day sharks!), a straight 'distal' end (the portion of the tooth that faces away from the snout) and a series of deep wrinkles that stretches up to the length of the tooth. Eocharia on the other hand, did not yet develop these very unique teeth.

When one considers the sheer unlikelihood of fossil preservation combined with the unlikelihood that the preserved fossils are not only exposed to the mercy of nature, but found by a far younger species of bipedal mammal with enough knowledge to either extract it and study it or tell people who can... the fact that we can trace the history of evolution as efficiently as we can never ceases to amaze me, and probably never will.

Busy, busy, busy...

So here's a dramatic sloth.

The most open dinosaurs you've ever seen!

Ye happy few (band of brothers, etc.):

Mike Taylor, Matt Wedel, and Andrew Farke have put together a project whose sheer scope and most importantly accessibility is absolutely remarkable. The basic idea is to create a massive database of Ornithischian bone measurements for various lines of research (both their own, and in the future, anyone who can use them!), starting out with an in depth statistical look into the development of quadrupedalism within the Ornithischia (when it was done, what strategies were used, which groups utilized these morphologic changes sooner in their development... all sorts of possible questions can be answered). And most importantly, anyone can contribute (and potentially be listed amongst the authors)--to find out more, visit their website!

http://opendino.wordpress.com/

Hope you're as thrilled about this as I am!

Giant theropod trackway found in the Upper Jurassic of Morocco.

This isn't just exciting and seriously awesome--it's seriously exciting and slightly more than seriously awesome.

Several researchers have just reported on a series of trackways found in the Upper Jurassic beds of Morocco--though there are several different varieties of tracks found in the area (a huge theropod, a smaller theropod and a sauropod), the tracks of the largest theropod are absolutely massive--the largest measuring 80 cm (from the posterior to anterior margins) by 76 cm (medio-laterally).

Though the exact size of trackways can be distorted by the substrate the trackway was found in (more on that later), in contrast a probable Tyrannosaur footprint found in the Hell Creek Formation (described by Philip Manning amongst several others) measures 72 cm anterior-posteriorly and 76 medio-laterally.

Though Morocco is no stranger to massive theropods (for example, Carcharodontosaurus is estimated at as much as 45 feet in adult length, with a skull several inches over five feet), this trackway's position in time shows that African Gondwanan theropods achieved a massive size fairly early in their evolution (though the exact identity of the track's owner can't be directly confirmed).

Considering the spotty record of African dinosaurs in general, especially in the Jurassic, this is beyond remarkable!

References--

Boutakiout, M., Hadri, M., Nouri, J., Díaz-Martínez, I. & Pérez-Lorente, F. 2009. Rastrilladas de icnitas terópodas gigantes del Jurásico Superior (Sinclinal de Iouaridène, Marruecos). [Gigantic theropod footprints from Upper Jurassic trackways (Iouaridène syncline, Morocco).] Revista Española de Paleontología, 24 (1), 31-46. ISSN 0213-6937.

Manning, Phillip L., Ott, Christopher, Falkingham, Peter L.-- A Probable Tyrannosaurid Track from the Hell Creek Formation (Upper Cretaceous), Montana, United States--PALAIOS 2008 23: 645-647

So it turns out...

That archaeologists are also constantly mixed up for paleontologists.

Real content coming soon, I promise!

Every geology lesson you'll ever need to know--

Dinosaur of the Week--Kryptops.

Back from the field! Working on resizing some photos for a photo post tomorrow.

*****

Evolution is a funny thing. It's sensitive to countless conditions, both based on one's environment and purely random chance (we owe our entire existence to one of these catastrophic chance events). But if there is one thing that truly forces diversity amongst animals (given the time, of which the Earth has plenty), it's separation--something that possibly no animals have seen more of throughout their evolutionary history than the dinosaurs. They saw the Earth as one massive continent (the famously known Pangea) and they saw it torn apart, sent in all directions. These separation events isolate populations of animals, who are then able to interbreed independently--and with the newly found selective pressures added to them within their own individual environment, evolution accelerates to new levels (possibly one of the best evolutionary accelerants outside mass extinctions!). This effect is known as vicariance. It was this vicariance effect (spurred by the opening of the Tethys ocean--which separated Africa, South America, Australia, Antarctica, India, and Madagascar from the rest of the world--forming the now long gone continent Gondwana) that helped spawn the subject of this week's blog--Kryptops.

Kryptops, discovered in the Ténéré Desert of central Niger, is the oldest known member of the Abelisauridae, a group of dinosaurs that look uncannily like large bipedal semi-reptilian (more dinosaurian) pitbulls, with short snouts and stout skulls. Take, for example, this Carnotaurus (though its crazy amount of cranial kinesis is something relatively unique to the genus)--

One of the most distinctive features of the skeletal remains discovered thus far of Kryptops are the short grooves and pits that cover the external surface of the Maxilla--one of the bones in the upper jaw. Though this sort of rough surface is something that is characteristic of Abelisaurids and some Carcharodontosaurids, they indicate that Kryptops may have been covered with a sort of Keratin-style mask on its face (thus the name--'Covered Face').

Like all dinosaurs, Kryptops was equipped with a sort of internal tooth factory--in which teeth grew and fell out constantly. Broken teeth are very common finds at various dig sites, which are often used as indicator of scavenging activity--the tooth would break off the hard bone and either fall on the ground or become swallowed with the meat (which in turn eats the enamel coating--if you ever chance upon a fossil tooth without, it's very likely that it's spent some time in the innards of a dinosaur!)

(Quick snapshot of an example--tooth on the left is most likely from the Tyrannosaurid Albertosaurus with the enamel still attached, while the tooth on the right belongs to Daspletosaurus sans enamel--both were collected in the field this last week)

Kryptops, like other Abelisaurids, likely had 17-18 teeth on the Maxilla--its discoverer removed a small portion of the jawbone to expose the tooth replacement system (in this case, in the 8th alveolus--or tooth socket) for its published scientific description.

The discovery of Kryptops helps shed some light on dinosaur evolution, showing that the derived (most evolutionary recent) features of the Abelisauridae existed before the Early Cretaceous ended. And as little as we know about the history of Mesozoic life on Africa, any information at all is a treasure. Even still, it's largely a blank slate with many new fascinating discoveries to be found in years to come.

Off to the field.

Will be back on the 9th of August; with luck I'll have photos and such of the trip!

Dinosaurian death in decidedly drenched dirt.

Well, make that just wet enough for some less than ideal results for at least one group of dinosaurs!

Just got done reading a paper entitled Mud Trapped Herd Captures Evidence of Distinctive Dinosaur Sociality, and it's a really cool read; especially if you have an interest in both taphonomy (what happens to an animal--in this case fossilized--after it dies) and dinosaurian behavior.

An excavation done in the Ulansuhai formation (late Cretaceous in age) of inner Mongolia turned up a group of at least thirteen separate specimens of the ornithomimid Sinornithomimus who were all found on a single geologic horizon and in very close proximity. Utilizing the sort of detective work essential for a field like paleontology (like a sleuth in some crime thriller, we have to use as many tools and conceptions as we can to get to the bottom of the case!), the paleontologists steadily unearthed a fascinating story.

First off, the geology of the locality held many different hints of information--like the presence of fine-grained layered deposits of rock and dirt that would alternate between very thick and very thin sections laid down in such a way as to suggest a non-fluvial (non-river caused) depositional environment. Various fossil ostracods (a sort of shrimp-like animal) helped support this.

However, the rocks told more of a story--in one layer in particular, this lakeside was drying up and fast--leaving various features of an arid environment (evaporites and the like). It was this horizon where the dinosaurs were found.

Twelve of the thirteen ornithomimids were found in an upright posture, stuck in a highly viscous material created by certain kinds of drying clays. Most (ten out of thirteen) of the skeletons were angled between 87º and 188º, which also lends itself towards a mass death at a single instant in time (a chance alignment for that number of specimens within that range of direction is very, very low).

One of the many really neat things about this find is the fact that the directionality the animals died in greatly influenced the bones and pieces that were missing from the skeletons--animals that died with their belly facing the ground most often had their gastralia (ribs found in front of the gut) and their stomach contents at the time of death preserved, but were missing dorsal (back) vertebrae and their respective ribs. On the other hand, the animal that was found on its left side had right rib elements missing. This is highly indicative of scavenging--after death and before complete burial, the exposed surfaces were eaten by opportunistic feeders.

Interestingly, the ilium (the largest of the hip bones) was missing in most of the specimens, and --though it can't be said for certain--this is also likely due to scavenging given that a. it probably would have been exposed to the surface on most of the specimens and b. it has a massive amount of muscle tissue to attract local carnivores. However, several of the Ilia appear to have weathered off, and very well may have survived to the point of burial.

Bone histology studies (research into the microstructure of the animal's bones) as well as relative size comparisons show that these animals were all juveniles or sub-adults, which is absolutely awesome in many ways--many bone beds containing the skeletons of non-avian juvenile dinosaurs have been found before, but because there was little taphonomic evidence to say for certain that they dead as a group or if it was a chance washing, this aspect of dinosaurian behavior was still slightly up in the air. But because this bone bed also contains similar age ranges, and the detail of taphonomy is so intense, it helps prove that previous similar finds were no accident!

All of this information helps us paint a picture of the scene--a drying lake bed, many millions of years ago attracts a roaming group of juvenile Sinornithomimus (the adults and infants are presumably nesting and traveling elsewhere). They're parched, thirsty beyond belief--and in temperatures well over 100 degrees, water is not common. They reach the watering hole, and though the water is stagnant and awful tasting, it was the most water they've had in days--but something goes wrong: they're stuck. They struggle, letting out distress calls in hopes that others are near--and as they try to pull themselves away from the sticky mud's grasp, they push themselves further in yet. After what could be hours, they fall over dead--struck by overexerting themselves in the scalding desert heat. The lake bed progressively dries further, and scavengers take the opportunity to snag a meal of what's exposed. Eventually the bodies are entirely buried with mud, and become fossilized over the aeons--lost in memory until a chance encounter with an entirely different group of bipedal animals, who map and detail their discovery for the world to see.

Reference--

Varricchio, D.J., Sereno, P. C., Zhao, X., Tan, L., Wilson ,J. A.,and Lyon, G. H.2008.Mud−trapped herd captures evidence

of distinctive dinosaur sociality. Acta Palaeontologica Polonica 53 (4): 567–578.

Dinosaur of the Week--Spinosaurus.

This is Egypt, a largely desert-covered country in Northern Africa, possibly most famous for its pyramids and other traces of ancient, long gone civilizations.

And this, roughly, is Egypt 110 million years ago.

Through a study of its geology and evaluations of the local fossil record, we've determined that in aeons past Egypt was very similar in appearance to the modern day Florida Everglades, with scattered mangrove swamps and intensely widespread vegetation.

However, there were some fairly recognizable differences. For example, you're not likely to find this guy in Florida--

Spinosaurus, a giant theropod dinosaur famously featured in Jurassic Park III. Spinosaurus is the last known member of a group of dinosaurs known as the Spinosauridae, whose members stretched from modern day Europe (Baryonyx) to Niger and Morocco in northwestern Africa (but was then called Gondwana). Though we have slightly more information on the animal now than has been the case in the past, Spinosaurus is still something of an enigma, with an absolutely enthralling and fascinating history. It was first discovered in the isolated deserts of Egypt by German paleontologist Ernst Stromer in 1912, known from a fragment of its skull and several vertebrae characterized by an absolutely massive spinous process (the portion of the top of the vertebrae that sticks up, or as we paleontologists unnecessarily put it 'extends dorsally') that stretched up to seven feet in length--these vertebrae would form together to create a large sail structure. Along with the holotype (the original find that a group of dinosaurs is based on) of Carcharodontosaurus, Stromer left the Egyptian desert, and had the specimens shipped back to Germany years later (after running through many hurdles to get them returned).

However, when they finally arrived, Stromer saw practically every single specimen in pieces--destroyed by the bumpy roads and inefficient carrying. For the next several years, he would reassemble and scientifically document and describe each of them, taking both photographs and producing detailed drawings.

But for all his work, every one of them were demolished into fine dust during World War II, when an Allied bombing run missed its mark and destroyed the museum that contained them. For years, it was all that had been found of this dinosaur, and was shrouded in mystery through those few remaining photographs and drawings. But very recently (within the last couple decades), new specimens of Spinosaurus have been unearthed, helping shed some light on the animal. These find include several more vertebrae, and and a couple jaw fragments (one of which--a bottom jaw, or 'dentary'--may represent a new species of the genus).

By the shape of its skull and teeth, it's been suggested that Spinosaurus was a largely piscivorous (fish-eating) animal, but was large enough (estimates put it as much as 58 feet long) that it could have certainly predated on smaller prey as well (a modern day analog would be the Grizzly Bear).

Dinosaur bite marks--

One aspect of paleontological research that has always fascinated me is how amazingly similar many of the events that occurred countless millions of years ago are to those found in modern ecosystems--in this case that of the countless and wide-varied interactions between predators and their prey, and even those between the predators themselves. One of these behaviors is something known as 'head biting'--a behavior observed amongst living animals in which competing rivals (over a mate, territory, a corpse, many things) fight amongst each other for control over whatever it is that they have their eyes set on. And because each of these animals are trying to assert their dominance over the other and would like to keep themselves as intact as possible, the head is a frequent target (keeping the rival in their sights). Also, because carnivores of aeons past had the same goals in mind as those living today (self-preservation and reproduction) and very similar tools to do so with (teeth and jaws!), they very likely ran into similar encounters and bouts of combat. As it turns out, we can find signs of these encounters throughout the fossil record!

This is a drawing of the partially reconstructed skull of an animal called Sinraptor, found in the deserts of northwest China. Each of the dark black lines outline the path of bite wounds that Canadian paleontologist Phillip Currie believes were caused by a conspecific (another Sinraptor). What is unique and so absolutely cool about this find is the fact that it allowed Currie to reconstruct the event in fascinating detail (given that it occurred over a hundred million years ago!)--two carnivorous dinosaurs faced off over a number of possible things (food, territory, etc.)--the tensions breaks, and one of the pair snaps its teeth at the other on the right side of the face and lower jaw with the right side of its mouth (measured by the angle and direction of the bite marks). However, as evidenced by the fact that the injuries were partially healed we know that the dinosaur in question (somehow) fled the scene. On the other hand, not all conspecific combat avoids mortality. In fact, we have evidence of outright cannibalism by this guy--

Majungasaurus, a large theropod dinosaur that lived in modern day Madagascar 70-65 million years ago. One find in particular viscerally fleshed out the defleshing of one such animal by another of its own species--the tooth marks on the bone match the dinosaur's teeth perfectly. Looking at today's ecosystems, this sort of thing is none too surprising--it occurs more frequently than many realize. What is exceptional (being that fossilization alone is very rare) is the signs of its existence being preserved after so long! However, encounters were certainly not limited between the carnivorous dinosaurs themselves--we have also uncovered fantastically detailed evidence of predator/prey interactions (both of animals that were scavenged and animals that escaped attack). At the centerpiece of a pseudo-debate involving the feeding behavior of the Late Cretaceous dinosaur Tyrannosaurus is a skeleton re-described by paleontologist Ken Carpenter (which was first discovered by a man called Barnum Brown in 1933)--a series of its caudal (tail) vertebrae was fractured, with at least one portion of the 'spinous process' completely broken and still several others kinked. On these spines were several tooth marks that match the exact shape and size of those belonging to Tyrannosaurus. But, because the bones show signs of healing, we know that it escaped for at least some time (and possibly died due to a bone infection) created by the bite. Also like many carcasses found in the wild today, bones of various dead animals would have scattered to the four winds by both assorted predators and scavengers, and as much of the bone as possible would have been picked clean. One such find is quite indicative of just that--a Triceratops pelvis collected by the Museum of Pennsylvania with a bare minimum of twelve bite marks, and as many as 33.

Fossils Encased in Mudstone--Part I

Started preparation work on this bastard last week--and armed with a nothing but a chisel, hammer, and a few brushes... it's slow going.

I won't be removing the fossils themselves from the block to give a visual representation of the deposition and burial of whatever may lie inside. 

Thus far I have exposed a large chunk of fairly unidentifiable bone, a diminutive rib of something or another (possibly some sort of small lizard), and a tiny three-chambered shellfish.

Will update with new photos as progress is made! 

PS--I will accept any an all air compressor donations.