Monday, December 26, 2011

Deinonychus Prey Restraint

This is an illustration based on the new paper by Fowler et al, which discusses a likely possible method of predation by Deinonychus and other dromaeosaurs (the "raptor prey restraint" model, or RPR). This excellent publication is available free to download. It suggests that the unique foot morphology of dromaeosaurs was an adaptation to take prey in a very similar manner to extant birds of prey: by grasping with the foot claws, digging in with the hypertrophied "sickle" claw, and tightly hanging on to the prey animal as it struggles and thrashes around. The dromaeosaur would then begin to feed on it while it's still alive, until it finally dies from blood loss and organ failure, all the while standing on top of the animal to pin it down (a likely use of the unusually short ankles found in dromaeosaurs) and using primitive flight strokes with its "wings" to maintain balance.

The primary animal of study in the RPR paper is Deinonychus, so that's what I've drawn here. It is shown preying on the hypsilophodontid Zepheryosaurus. Though Deinonychus is usually depicted in a dense floodplain environment, here I've reconstructed it amongst some higher-altitude arid North American mountains.

This is my version of a Christmas dinner. :)

Monday, November 7, 2011

Liaoning details

By popular request, a few detail shots of my last upload.

Thursday, November 3, 2011

Liaoning Scene

I consider this to basically be my magnum opus of paleoart at this point in time. I've spent months on all of the details and shading. The full resolution version is about five times larger than this one. I am SO glad it is finally finished.

This represents a hypothetical scene from the Jehol group of early Cretaceous Liaoning of China, something like 122 million years ago. Several animals from the Yixian formation are represented here: Sinornithosaurus millennii, a feathered dromaeosaurid dinosaur; Liaoxitriton zhongjiani, a salamander; Alloraphidia, a snakefly; Epicharmeropsis, a mayfly, and a dead Callobatrachus, a frog.

The gliding dinosaurs are meant to be generic microraptorine dinosaurs, not Microraptor gui specifically, in order to avoid the slight anachronism caused by placing Microraptor and Sinornithosaurus in the same scene. Despite that, it is (obviously) based on Microraptor gui (I started this scene before I learned that the two animals were not quite contemporary, I admit).

This illustration will be the section header for the chapter on feathered dinosaurs for the book on evolution and religion that I'm currently working on with a few other people. Once again, thanks to Jon for shading critiques and suggestions.

To see a larger version, please click here.

Wednesday, October 19, 2011

Jehol Juxtaposition

This picture was never meant to be. It is technically a mashup of two very large, time-intensive and high-resolution pieces I've been working on for months. I seldom upload lately due to the fact that the bulk of my artistic energy of late has been going into these two pictures.

Since both images are intended for print, a lot of the detail in the background will be lost when I finally resize them to upload for the internet. I thought it would be nice, though, to show some elements from each image that will be downsized in the final versions. They seemed to fit together well. Think of it as a glorified WIP.

This particular scene depicts Microraptor gui, a tiny four-winged gliding dromaeosaur, and Epicharmeropsis, an ancient mayfly.

Photoshop CS4

Sunday, October 16, 2011

Sinornithosaurus with prey

Sneak peek at an upcoming larger image. Sinornithosaurus with its prey, a freshly killed Callobatrachus.

Thursday, September 22, 2011

Talos sampsoni

This is the newly described troodontid Talos sampsoni of Utah's Kaiparowits Formation. The described specimen of this derived troodontid had an interesting feature, which is that the sickle claw-bearing toe of the left foot had been broken in life, including a surface lesion, and had then healed. The authors speculate that the toe may have been damaged in some sort of physical trauma or infection. A popular theory is that it was damaged in the act of predation, though that remains a speculative idea.

Here I've reconstructed it inspecting the hurt toe after the injury had occurred, perhaps cleaning it as best as it was able.

The paper is open access, so please feel free to read more about it here.

Saturday, July 16, 2011

Saurornitholestes langstoni

Saurornitholestes, a remake of an earlier image.

Around a year ago there was a new discovery involving fossilized scratch marks, presumably from the foot claws of a maniraptoran, at the entrance to an ancient primitive mammal burrow. I illustrated it at the time and some of you may remember it. However more recently a museum representative from Denver contacted me wanting a larger resolution version of the piece, so I updated it accordingly and added some additional details for accuracy and interesting-ness, including the trio of Pteranodon longiceps from a recent submission. (This is not the highest resolution, obviously, but I think the improvement in detail is noticeable.)

To reiterate the study:

The scratched-out burrows provide a unique insight into both the behavior and diet of these dinosaurs, which must have occasionally dug out the burrows of their prey, like many modern predators do. This trace fossil was found in Utah and is dated at around 80 million years old, which means the claw marks could belong to several different small dromaeosaurs or troodonts. I've illustrated the dromaeosaur Saurornitholestes here, which was similar in size and anatomy to Velociraptor. The findings were published in the journal Geology.

Thursday, July 14, 2011


Microraptor sitting on a branch. Quick sketch from class today, nothing special. Done without references, so possibly inaccurate.

Wednesday, June 29, 2011

Pteranodon trio

A trio of Pteranodon longiceps, two males and one female. Portion of an upcoming larger piece.

Photoshop CS4.

Sunday, June 12, 2011


Something that's not a dinosaur, for once. This is the prehistoric frog Callobatrachus from Early Cretaceous of northeastern China. This will be the prey animal that Sinornithosaurus is eating in the Liaoning scene I'm working on. I also put it in the Wikipedia article on the animal, which I also wrote.

Saturday, June 11, 2011

Sinornithosaurus poses

In slowly completing a large, detailed Liaoning scene, I've been working on a sinornithosaurid. I have two poses I'm trying to choose between:

The top one is looking up passively at two Microraptors as they swoop down from above. The lower image is meant to be a bit more dynamic, and will be drawn protecting either a nest or mantling over a kill (perhaps a snake or a small mammal). I can't think of having seen artwork of a dromaeosaurid mantling. This is a behavior typically observed by birds of prey after making a kill: they will spread their wings and tail and crouch over it, looking menacing to anyone nearby who might consider stealing it.

I think I like the bottom one better.

Keep in mind that these are not meant to be representative of Microraptor gui and Sinornithosaurus millennii specifically, as those two species are from two different formations (Jiufotang and Yixian, respectively). Even though the species likely did not overlap, I think it's perfectly reasonable that the genera may have.

Microraptor T-shirt?

This is technically a work in progress for a much larger, more complex image, but I thought that the basic design was snazzy enough that I made a t-shirt out of it. Definitely the one thing missing from everyone's lives, a Microraptor t-shirt.

Utahraptor ostrommaysorum

Reconstruction of Utahraptor ostrommaysorum intended for the Wikipedia article on the animal. Scott Hartman's skeletal used as reference. I went to painstaking lengths to make this as accurate as possible given the available data on the animal.

Photoshop CS4, June 2011.

Sorry for all of the rapid-fire posts over the course of this past day. I will be trying to update this blog more frequently nowadays as I complete it.

Anchiornis: sexual dimorphism

Though this was intended as an entry for an envelope art contest on James Gurney's blog, it gave me an excuse to draw something I've wanted to for a while: my speculative perception of sexual dimorphism in the troodontid Anchiornis.

Anchiornis is the first non-avian dinosaur for which true colors have been determined from the fossil, and as such we now know that it looks strikingly similar, coloration-wise, to a modern woodpecker. Most woodpeckers (with some notable exceptions, like the pileated woodpecker) are sexually dimorphic, in that the male typically possesses bright red coloration on its head, while the female lacks most or all of the red. Here, I've drawn the male closer to the viewer, with his characteristic red crest and facial markings. The female, behind him, lacks the red facial markings and her crest is a duller greyish-brown.

This was drawn on a regular #10 envelope with ink, Prismacolor marker & pencil, and white acrylic highlights. Working on such a small scale with traditional media is a pain in the butt, and the details suffer somewhat as a result. This has also been touched up digitally, but the physical contest entry will not enjoy this benefit.

Thunder Thighs

Illustration of the new sauropod Brontomerus whose description was released iin February. Brontomerus means "thunder thighs" in Greek, referring to its massive ilium which would have supported the largest leg muscles of any sauropod. Its describers theorize that it may have used these powerful legs to kick at predators to defend itself. This picture is loosely based on the official reconstruction by Francisco Gascó, which is based on the data provided in the paper.

See the National Geographic article here,
And the Wikipedia article here.

Photoshop CS4, February 2011.

The Tree of Yum: Plantae

Apparently blogger resizes this to an extent that makes it unreadable, so please click here to view.

This is a bit different from my usual fare, but still worth sharing. Recently I was idly curious about how common fruits are related to one another. Everyone can figure that berries are mostly related, for instance, and peaches and plums are probably related. But beyond that, the evolutionary relationships between fruits don't seem very intuitive. I tried finding a phylogenetic tree of this online, but couldn't find one. So, I spent a few hours researching and made my own.

My initial feeling that these relationships aren't very intuitive was proven correct. In fact, a lot of the relatedness I found seemed pretty bizarre to me, though I'm no botanist. I think the main reason for this strangeness is the power of human artificial selection, which has produced the vast majority of the plants found in this chart. We can do pretty crazy things to plants (and animals, just look at dogs) with a few thousand generations of selective breeding.

This isn't meant to be extremely scientific: I've divided the clades very simplistically, and the branch lengths aren't meant to represent divergence time. (I.e., no bootstrapping :p) I tried dividing them into monocots vs dicots when I first started, but quickly learned that these groups are paraphyletic. Plant systematics is messy as hell, and there are a huge number of "unranked" groups that I mostly didn't include here.

Also, this should be obvious, but not every fruit/vegetable/herb/nut in existence is represented here, just what I considered to be the largest or most important groups. For example, parsnips are very closely related to carrots, but I left them out because let's be honest, who the hell even knows what a parsnip is? I left out a lot of herbs and stuff too, because those just go on forever. At 1 MB, it's already big enough as it is.

Animal version coming eventually!

Photoshop CS4, February 2011.

Concavenator corcovatus

Illustration of the new theropod Concavenator corcovatus described in September. Concavenator was a mid-sized carcharodontid dinosaur with two very unique features: elongated vertebrae forming two "humps" on its back, as well as what might be primitive quill-like integument on its arms. The validity of the quills is debated, though, as the knobs found on the bones may be muscle attachment points rather than quill anchors.

The discoverers theorize that the elongated vertebral crests may have supported a hump whose function was in thermoregulation. While I neither support nor deny that hypothesis, I chose to illustrate the animal beginning to rustle from rest at dawn, as it absorbs some of the sunlight needed to start its day.

Photoshop CS4, January 2011.

Of the Mountains

This was a housewarming gift for a friend. The Velociraptor's colors are not meant to be realistic. The background is significantly inspired by the mountains of western NC, where I hail from.

Photoshop CS4, November 2010.

Coffeeraptor Mugs for Sale!

I'm selling mugs with this design at CafePress - in tea or coffee variety. Give it a look if you're interested!

Balaur bondoc

Awesome new dromaeosaur was discovered recently from late Cretaceous Romania and described in September's online preprinting of PNAS. Here's an article.

The weirdest thing about Balaur bondoc is that it had double sickle claws on each foot, with the additional claw being the hallux that evolution had modified into a retractable enlarged claw. It also had a reduced and nonfunctional third manual digit, unlike all other known dromaeosaurs. More recent speculation on the animal indicates that the extended first digit is not actually a "second sickle claw" as the media purported, but rather an enlarged weight-bearing digit, perhaps because Balaur may have been "chunkier" than the average dromaeosaur.

Awesome critter!

Here's the Wikipedia article for anyone interested.

Photoshop CS4, September 2010.

Saurornitholestes: Digging for Dinner

This is an illustration of a new discovery involving fossilized scratch marks, presumably from the foot claws of a maniraptoran, at the entrance to an ancient primitive mammal burrow.

The scratched-out burrows provide a unique insight into both the behavior and diet of these dinosaurs, which must have occasionally dug out the burrows of their prey, like many modern predators do. This trace fossil was found in Utah and is dated at around 80 million years old, which means the claw marks could belong to several different small dromaeosaurs or troodonts. I've illustrated the dromaeosaur Saurornitholestes here, which was similar in size and anatomy to Velociraptor. The findings were published in the journal Geology.

All of the news articles I've seen describing this finding have included pretty crappy illustrations, so I was inspired to create my own. I may also send it to the authors of the paper.

Photoshop CS4, August 2010.

The Seventeenth Colossus

Quick painting for an assignment in my illustration class. Homage to one of my favorite games, Shadow of the Colossus.

Photoshop CS4, March 2010.

Time traveling chickens?

Make good meals for Velociraptors.

Photoshop CS4, May 2010.

Anchiornis huxleyi

The 9th illustration for the book. This dinosaur was not originally part of the lineup of feathered dinosaurs that I needed to illustrate, but the new specimen described in December of 2009 made it clear that it needed to be included, since it was a beautiful example of a feathered troodontid older than Archaeopteryx.

I ran into an unfortunate predicament with this painting that I hadn't yet experienced in my artistic career. Right when I had completed it, a new study was released that described in fantastic detail the coloration that this animal's feathers would have had in life. I was extremely discouraged by this news, but since this painting is going to be published and needed to be as accurate and reputable as possible, I painstakingly repainted the animal to reflect the findings of the new study.

Here is the old version of the painting.

Oil on canvas, March 2010.

Caudipteryx zoui

Number 8 of the feathered dinosaur illustrations for the book. This is Caudipteryx, a flightless, feathered, basal oviraptorosaur from the Yixian Formation of China. It's currently the oviraptorosaur with the best-preserved feathers. This dinosaur was around the size of a large turkey and is named after its rather impressive tail fan, the feathers of which are clearly preserved in its fossil.

Though not as birdlike as certain other dinosaurs, Caudipteryx did have pennaceous-like feathers on its arms, similar to modern birds but without interlocking barbules, to the best of my knowledge.

Watercolor and Prismacolor pencil, September 2009.

Sinosauropteryx prima

I haven't updated this blog for over a year, but I'm going to start try to do so regularly again. Here's the seventh book illustration. This is Sinosauropteryx, from the early Cretaceous of China's Liaoning. It is famous as being the first dinosaur found with fossilized feather impressions, and one of the most primitive. Its feathers were very simple, and would have been little more than furry down. It was thought that this animal's body covering may have been collagen fiber remains instead of feathers, but more recent analysis of its long tail - which shows an alternation of light and dark bands - shows that it was more likely to be primitive down.

Watercolor and Prismacolor pencil, September 2009.