Sunday, May 31, 2009

Carcharadontosaurus


Carcharadontosaurus, a relative of Mapusaurs from Africa.

The last week or so I've been engaged in a discussion about theropods living in groups with a fellow blogger and Paleontologist. Basically it boils down to this. Since birds and crocs are dinosaurs closest relatives we should only use them it infer any behavior and biology. I disagreed and lots of comments and emails were exchanged. I was given a copy of the 2007 Deinonychus paper. A paper which is supposed to explain the feeding habits of Deinonychus. In it, the paper basically uses the ora, or what we in the west called the Komodo Dragon, as a comparison to the kill site were the 'raptors' were discovered. 4 raptors were found along with the carcase of a juvenile Tenontosaurus. The original idea being that the tenontosaurus either fell on or killed the 4 in the attack that cost it it's life. The fell on thing is kind of strange but the site is odd in itself. It appears that one fo the raptors 'killing' claws was imbeded in the tail tendons of another raptor. There were lots of shed teeth so we kow more than the 4 raptors were present. The paper argues that this site is simiar to ora kill sites, as the ora is know to be canibalistic and they explain the site as a single raptor killing the Tenontosaurus and then the others coming in and a sort of feeding frenzy ensued, during which things got out of hand and 4 of the raptors were also killed. We are told from this we can assume that this is how EVERY theropod dinosaur should now be interpreted as acting, single hunter and then a group comes in and they fight over and eat the kill, just like oras. It should be the 'fall back' position. I disagree. While the site is strange an equally plausible postion is a rival group of raptors showed up and a fight ensued. It explains the shed teeth, the claw in the other raptors tail, and the 4 dead animals. Am I sure of this..? No, but it's just as likely. The point is we don't actually know. It's a guess, an educated one but it's still a guess. But to claim that EVERY theropod should be cast as having the same exact behavior is just at odds with ALL other animals. No predators, even closely realted ones, act exactly the same way. Most birds hunt alone, but some hunt in groups. Some live alone, others in groups.

The Ora is a strange animal, it's the heaviest lizard, it lives on a small island (or group of islands) with very limited resources, it's now found to be venomus. It's cold blooded. Not very similar to theropods, who had much greater resources, continents to roam around on. Were most likely warm blooded, and not venomous (that we know of.) To just use the one lizard is just wrong. Other veranids don't behave that way, even ones closely related to the Ora. I fail to see how this should be the fall back position and how this is good science. Good science should say we don't know... We have some evidence for some theropds living together, but it's open to interpretation.

Case in point the Mapusaurs site. 7 individuals of various ages. were found burried together. I was told this shows a predator trap, but in every other predator trap (similar to the Le Brae tar pitts, but no tar) there are more than one speices of predator. In fact we have traps like this in the US, one in Utah with LOTS of Allosaurs, some ceratosaurs, some sauropods, a Torvosaurus... lots of different animals, this is a classic predator trap. But to find 7 individuals with no signs of canibalism.. no other animals... a trap that just caught one specific animal around the same time??? That's the best explination? Not that they were living together and were all killed at the same time via flood or volcanic gas or whatever? I'm even will to say we don't know for sure and will most likely never know, unless the bones were all jumbled together, that would mean they most likely died and decomposed together. But that's all we'll ever know for sure.

I keep being told that we can't use mammals for anything related to dinosaurs. But I just read a very interesting post over on Tetrapod Zoology about the neck posture of sauropods*. It turns out THEY used mammals for their comparison. Wait weren't we not supposed to use them?? And then in another post, Darren mentions another new paper about reptiles and birds playing... and how did they kow they were playing... why they were comapared to mammals of course! So what I'm being told is, it's only ok for SCIENTISTS to compare mammals to dinosaurs, just not some frindge artist who doesn't know any actual science.

I wouldn't have brought this up but the person I was arguing with has felt compelled to mention it on their blogs at least 3 times already, even after the papers comparing mammals to reptiles, birds and dinosaurs. I can't really comment there because it isn't in English and the translators are really bad. So I can't be 100 percent sure of what is being said, so I have to go off what I've gotten in English here.

I am of course, willing to change my mind when and if good evidence is ever found. But for now what's there is less than convincing, even to this frindge artist.

Best,

Brett

* Disclaimer: This paper used turtles, lizards, crocodilians and birds and mammals for neck postures. I focused on the mammals to prove a point.

Sunday, May 24, 2009

Megaraptor idon'tknowwhatasaurus

I think I might have figured out how to put text above the first image (yeah!) Anyways, I wanted to put up strickly colored stuff here on Carnosauria. But I'm a bit behind work wise and so here are a few scene type drawings of the pencil/line art before coloring. These are both images of the mysterious Megaraptor....

Originally thought to be a large dromeosaur, the claw turned out to actually be from the hand, as an almost complete forearm and hand were found. So that tosses this animal out of the 'raptor' clan (sorry Jurassic Park fans!) But were does it go now? That's the probem. I've seen several papers on it, but it appears to have anatomy similar to 2 lines of theropods. The spinosaurs and the carcharadontosaurs. When I was originally told about the change from foot to hand I was told it was, most likely, a spinosaur by several people inthe feild, it was also mentioned as a possible spinosaur in the Holtz/Rey dinosaur book called, simply enough, Dinosaurs (I completely forgot the name and had to google it, I feel like such a tool;). I liked the head design Rey used on his image so I kind of took that and modified it a bit, kind of a more robust Suchomimus.) But after I posted that image, I was told I was wrong...

I received several comments that a new paper would show that Megaraptor was, in fact, a late surviving carcharadontosaur. I actually read the paper, it still seemed up in the air to me, but not wanting to get even more comments telling me I was wrong I decided to draw it as a carchardontosaur for a book I'm working on (images seen here and some new ones with a few comic like scenes showing possible behaviours...)

I then recieved new comments that I was wrong and that another new paper showing that Megaraptor was related to a new spinosaur from Austrailia would prove it. I read that paper as well.... And to be honest. I have no fricken idea which group this thing belongs to. So until more fossils are found it's an idon'tknowwhatasaurus.

But what to do with the comic page..? I decided to modify it and changed it to a Mapusaurus, easy enough, I used that as the base for the restoration. But since Mapusaurus is older than Megaraptor the Carnotaurs are now fromthe wrong time... So I contacted a few fellow bloggers, Darren Naish and Brian Switek. They had some excellent ideas and Darren mention a few new animals that were comming down the pipeline. I'll post the changed image when I get that drive up and running but I wound up using Skorpiovenator, I just like the name;)

Best,

Brett

Monday, May 18, 2009

Mapusaurus, Neovenator and Eocarcharia


Another of the giant carcharadontosaurs from South America. I believe they have parts of 7 individuals. The most likely explanation is that it lived in some sort of pack. Related to Giganatosaurus, this animal preyed upon the giant sauropod Argentinosaurus.


Once considered a relative to Acrocanthosaurus, it's now thought to be an allosaur. Found in England, it was hanging around in the early Cretaceous with animals like Iguanadon and Baryonyx.


This is the earliest confirmed carcharadontosaur. Eocarcharia, was found in the same area and strata as the last post's Kryptops. Interestingly these theropods also lived along side of Suchomimus. This seems to be the theme for Gondwana in the Cretaceous, 3 giant theropods as the top predators.

Best,

Brett

Thursday, May 14, 2009

Kryptops

Right now this is the oldest known abelisaur. It's possible that this animal had some sort of beak
on it's face. It's an interesting idea, I might have to do a drawing of that;)

SO the dinosaurs have been a bit sparse lately. We ran out of room on the computer so we had to dump a bunch fo stuff onto a portable external drive. Unfortunately it take all the USB ports on the laptop so I have to unplug the tablet and I can't use the track pad. We have ordered a new USB hub thing but until we get it all the drawn dinosaurs are locked away on another drive.

I need to do a few new dinosaurs. So maybe I'll get some new ones scanned before I get the new hub;)

Best,

Brett

Sunday, May 10, 2009

Paleo art and Aerosteon

Aerosteon, it appears to be a later surviving Allosaur, or something very closely related. It had a respiratory system similar to modern birds.

Paleo art:

I've been drawing dinosaurs semi seriously for around 9 years now. I remember when artists like Todd Marshal and Luis Rey were just starting to get popular. I remember picking up the paperback version of Predatory Dinosaurs of the World (I just picked another hard cover of that one. That make 3 that I've bought over the years) while on a trip to Hawaii. I was amazed at what it had in it. Jurassic park had just come out and it had been about 8 years since I'd last really read bout dinosaurs.

The art in that book fascinated me. It was like nothing I'd ever seen before. Dynamic agile animals, feathered raptors. It was amazing. To this day Gregory S. Paul is a favorite artist of mine.

So what is this post about? Well it's been a few years since I started to try my hand at drawing dinosaurs, an the one thing I still see, is the influence of Gregory S. Paul. This is of course fine and dandy, I'm a big fan, his work is a great influence of mine. But most the artists who are so greatly influenced by him, and there are a lot, don't seem to try and develop their own style. They seem to have come to an approximation of Paul's and that's it, nothing new, no other influences. And while it's always great to see his art, the market has been flooded with clones. Now I'm guilty of this to a certain extant myself. I had a favorite comic artist that I aped, it's how I got hired originally. BUT after the initial honeymoon phase, I did try to branch out and develop my own style (I've heard it called the 'Brett Booth Beauty Academy'. Which I find endlessly amusing;)) I think I've made the transition to my own 'look'.

So what I'm trying to say is that IF you are a Paul clone, why not try and experiment with some other styles, I'm not trying to get people to draw like me, I already have those in the anthro world and some even in the comic world. But my hope would be to help expand the artistic styles of some of the artist that I see with a lot of promise to break out and become the next Gregory S. Paul. Oh, and for goodness sake PLEASE take a few basic art classes (I know a lot of the artists are self taught.) It will help with perspective and some basic design work, help create some depth in the pictures.

Of course some of you will say who the hell is this guy? He's not a professional paleoartist! True, but how many books with your name on it do you have on Amazon? I've draw thousands of illustrations for comics and the like, I've critiqued countless would be artists online and at shows. I have a degree in commercial art. I've been drawing comics for over 16 years. I'd have to have at least SOME design sense after all that (I'm not trying to toot my own horn just prove a point.) So why not take of the advice of another artist, try to expand on a good base and take your art to the next level.

Best,

Brett

Thursday, May 7, 2009

Sinraptor

A largish theropod form the late Jurassic of China. It's now stipulated that this animal is the precursor of the carcharadontosaur line.

Best,

Brett

Monday, May 4, 2009

Carnotaurus sastrei

One new and the other old. A late cretaceous abelisaur from South America. There are actually skin impressions of the this animal so we have a good idea of what it actually looked like. Well, except for the color;)

This animal reached a length of 30 feet, and had one of the strangest heads on any theropod so far discovered. But the strangest thing would be the 4 fingered hands. Only 2 of which had claws. The fore arm bones have been greatly reduced to be virtully non existant.

Best,

Brett

Sunday, May 3, 2009

Skorpiovenator


A Cretaceous contemporary of Mapusaurus, this is another of those funny looking abelisaurs. It's nae means scorpion hunter, due to the fact that there were lots of scorpions around the dig site;)

Best,

Brett

Friday, May 1, 2009

Deltadromeus


Deltadromeus is now thought to be a noasaur, off the abelisaur family tree. From Africa, it's another really big theropod around 40 feet. But this one is differnent, it's very gracile, built for running. The head is based off of the other known noasaur species and might be incorrect, it's a best guess at this point.

Being an ableisaur it's strange in that it has long arms and is larger than any of it's other known relatives. I beleive Carnotaurus would be the second largest at around 25+ feet. So this animal was a giant for the group. It's theropod contemporraries include Carcharadontosaurus and Spinosaurus, also giants, so there seems to be a trend of giant theropods in mid cretaceous Africa. There are a few other large theropod remains fond at the sime time and same area but they are too scrappy to make good identifications. So perhaps there is a fourth group of large theropods running around Africa that we don't really know about;)

Best,

Brett