Arts and Sciences
Issue: Volume: 31 Issue: 8 (Aug. 2008)

Arts and Sciences

Today’s animal kingdom comprises creatures of different sizes and shapes, from magnificent polar bears and playful penguins at the tip of the world, to the stealthy panther and agile monkeys of the equatorial jungles, to the enormous whales and flying fish that dwell in the oceans, to everything in between. So, too, was the case during the prehistoric periods.

We know what those present-day species look like; after all, we have living, breathing creatures to study and photograph. But what about those beasts from millions of years ago? How do we know what they looked like? Yet, ask any child and he or she can describe, in amazing detail, a Tyrannosaurus Rex, a Triceratops, or any number of popular dinosaurs that lived millions of years ago. That’s because scientists, paleontologists, and artists have worked together to provide as-accurate-as-possible visual representations of these dinosaurs based on a combination of scientific data (fossils, bone fragments), scientific theory and anatomy, and visual logic.

Indeed, most of us are quite familiar with the look of the long-necked Brachiosaurus, the spiky-back Stegosaurus, and the flying Pteranodon. But there are countless others whose forms have yet to be revealed, aside from fragmentary elements founds in fossils. And sometimes that is the only piece to this grand evolutionary puzzle from which French artists Marc Boulay and Sylvia Lorrain, partners of HOX.Studio in France, have to work. Rather than use fine brushes and chisels, as paleontologists do, this duo relies on pixels and polygons to “unearth” their find and give it a shape.

For years, Boulay and Lorrain have been working with Dr. J. Sebastien Steyer, a paleontologist at the National Museum of Natural History in Paris, making scientific reconstructions and models of creatures from the past, such as dinosaurs, marine reptiles, fossil amphibians, and more. Largely, their 2D illustrations are used to accompany scientific articles or scientific reviews in international publications and journals. Their 3D pieces are typically used by museums, scientists, and even in movies, including the upcoming IMAX fiction-documentary Sea Rex, shown in stereo 3D.


Re-creating extinct dinosaurs in CG involves many disciplines: (at right, from top) uncovering the fossil of a Dicynodon, the cleaned skull, the 3D model; (above) the final 3D rendering.
 
Boulay is an organic modeler, who provides the structure, or body, for Lorrain’s detailed textures, or skin. In his reconstruction, Boulay makes 3D models of extinct species using fossil evidence. Though a great deal of his work focuses on life that has been extinct for many millennia, he also sculpts or models living animals or species, such as insects, that are difficult to capture on film or in photographs. Lorrain’s work, meanwhile, entails texturing models of those extinct species and integrating them into a visualization of their natural habitat.

“Thanks to the various 2D/3D techniques of organic modeling andphotorealism, we are able to represent the past and thepresent, as well as imagine the future,” Lorrain says.
     
In the Beginning
A decade ago, Boulay, a trained sculptor, began focusing on an area that impassioned him: hyper-realistic animal sculpture and comparative anatomy. In the beginning, he sculpted dinosaurs and other creatures from clay before turning to 3D software. Today, he works closely with scientists, particularly paleontologists and entomologists, reconstituting species that existed before the dinosaur age. “Given that most of them have not been reconstructed at this time, the work is quite challenging,” he says.

Meanwhile, Lorrain first became involved with this type of unique work after participating, along with an international team of paleontologists, in a scientific mission to northern Laos that was organized by Steyer. The purpose of the mission was to search for fossils of mammalian reptiles, notably Dicynodons, from the Permian Period (250–300 million years ago). She really dug the work.

“The experience of being there, of seeing the scientists working in the field, and observing their daily hauls inspired me to no end,” Lorrain says. After Lorrain returned to France, she and Boulay began working on the 3D reconstruction of a Dicynodon with the a      ssistance and advice from specialists Lorrain had accompanied on her trip.

Observation, explains Lorrain, is the central tenet to the pair’s work: “Nothing is triggered without close observation.” To represent an extinct species in a hyper-realistic way, Lorrain and Boulay must first comprehend the creature’s anatomy, habitat, and locomotive functions, and consider its contemporary version, so to speak, through close observation. That helps them establish similarities between the past and present creature—a process Boulay likens to “profiling.” For instance, the pelican could find the Dsungaripterus in its family tree, and the shark may be a relative of the Liopleurodon.

“When I worked on modeling one of the first amphibians, called Acanthostega (an extinct species from the Devonian Period, about 370 million years ago), I set out by observing their living relation, the salamanders and newts, from tadpoles to adults,” Lorrain explains. In parallel with her own observations, she garnered additional infor­mation from scientists and specialists in this field, and supplement their research with extensive reading and browsing on the Internet.

The artists also must consider the habitat of the extinct creature, including original climactic conditions—all of which would have impacted its look. Often, Lorrain visits diverse natural sites, photographing sequoias, conifers, ferns, and various species of vegetation that have survived throughout the various geological periods. 

In fact, Lorrain’s process is much like that of a matte painter. She takes HD photographs of the animals that she has been observing and uses that information as a texture database for the CG models. “I tend not to use procedural textures, but only organic textures, which, in turn, I paint directly onto the 3D model using Pixologic’s Zbrush,” says Lorrain. “Macro-photographing the subject provides a subtlety and richness of texture that would otherwise be impossible to acquire.”

While Lorrain is doing research, Boulay begins his first 3D model, after which “serious collaboration with scientists can begin.”

The Science Behind the 3D
Before using Zbrush, Boulay built his sculptures with clay, an arduous and expensive process, requiring scientists to make numerous visits to his studio to validate the design at certain stages during the reconstruction. Moreover, Boulay had to build the sculptures to scale, a daunting task considering the very large, or very small, sizes involved, and then deliver the model to the museum. With 3D technology, these obstacles have been eliminated, enabling him to model many plants or animals that he was unable to consider before going digital.

First drafts of his models are now sent by e-mail, making the process much faster and easier for all involved. After the model has been authenticated by a scientist, Boulay passes it off to Lorrain for texturing.


Sylvia Lorrain re-created these Alanoropus and placed them into a “reasonable” environment.
 
When re-creating the creatures’ habitat, Boulay models a panoramic landscape using Terragen, a freeware scenery generator program published by Planetside Software. Lorrain then transforms it as necessary, adding 2D and 3D objects—vegetation, flying reptiles, waterfalls, and so forth—in Adobe Photoshop and Zbrush, respectively.

According to Lorrain, the advantages of working with CG are many, including the speed and ease that it affords her when making changes. Lorrain offers a recent example when she was texturing the Watsonisuchus. “I made the scales and scutes similar to those found on crocodiles because various indicators, such as the size, shape, and proportions of the extinct amphibian’s skull closely resembled this modern creature,” she says. “There was no way of validating whether they had such scales or not, but after extensive discussion with specialists in the field, they were more of the opinion that the skin was akin to that of a salamander.” In no time, she reworked the model to incorporate that change.

Alas, based on new findings, Lorrain may have to rework the texture yet again, says Steyer. Pending new discoveries of the post-cranial skeleton, which the field scientists hope to locate in the future, the model could return to the original scaly skin, retain a softer hide, or be given a hybrid of the two. “With CG, we can easily accommodate two or even three versions of a theory,” Steyer adds.

Furthermore, working in 3D enables Lorrain and Boulay to move the model around, zoom in, choose a specific angle for presenting the creature, and so forth. “It’s so easy to change the shape of a leg or the skin appearance of an animal modeled in 3D,” Lorrain says. “Undertaking the same maneuvers with a sculpture or a drawing means starting over from scratch each time.”

When the work calls for abstract creations, Boulay and Lorrain have more creative freedom. Hyper-realistic and realistic reconstitutions, however, involve a greater level of complexity and require a solid comprehension of the various fields relating to the subject: paleontology, anatomy, and life sciences.

“Illustrating the subject as faithfully as possible is the biggest challenge, hands down,” says Lorrain. While it is possible to obtain a reasonable idea of the anatomy of an extinct species by closely examining the fossils, texture is another matter, she points out. And so is determining color.

“Take, for example, the flying reptiles: A contemporary reference would be birds. The male’s plumage is often colorful. This serves a biological purpose in that it attracts the female’s attention during his courtship attempts. Peacocks have an extremely eye-catching plumage; the downside to such an ostentatious display is that the birds become easy prey to predators,” explains Lorrain. “In a similar vein, the Tapejara, a flying reptile dating back some 120 million years, had a crest more than a meter tall—something that would impinge on its ability to fly with ease. I presume that its crest served as a means of attracting the female’s attention, and that it was colored in such a way as to seduce. These theories allow me to work the entire gamut of the color palette.”
 
Digital Paleontology
While Boulay and Lorrain have been focused on this unusual work for a number of years, Steyer has only been using CG models in the museum’s Earth History Department for less then three years, ever since Boulay and Lorrain began working with CGI. According to Steyer, the 3D models are increasingly being used in various “paleo fields,” such as paleobiology (the study of an extinct species’ behavior), paleoecology (reconstruction of complete landscapes from the past), and biomechanics (how the bones and muscles are articulating and moving together).

Currently, Steyer is using the 3D images to study and better understand the fossils his group is reconstructing—how the creature walked, ran, climbed, jumped, swam, dove, flew, and flapped, as well as how (and what) it ate. Did it crush its food? Chew it? Pierce it? In particular, the CG techniques have proven ideal for anatomical observation, “to better observe complex and microscopic structures,” he explains. In the future, Steyer hopes to secure funding for additional 3D modeling and sculpting that can be applied to other facets of his work.

As a paleontologist, Steyer focuses mainly on teeth and bones—the hardest body tissues that are fossilized when vertebrate die. When he locates a fossil in the field, he cleans it (a time-consuming process), draws it, and compares it with other related forms in order to identify the object. “Then I put all the body articulations together and propose a reconstruction of the skeleton and of the beast, if I have enough comparative elements,” Steyer explains.


The artists, working mainly with Pixologic’s Zbrush, provide a variety of CG imagery that is used for various purposes, such as informational sources.
 
Until recently, this process was done entirely in 2D (some still is) because Steyer and his group were publishing papers of their work in scientific journals. “But with the 3D techniques, we enter into a new dimension,” he says. “Thanks to the Internet, we are now able to publish in 3D. And thanks to cinema, we are able to see dinosaurs and other creatures moving like they do in our dreams. Mark and Sylvia bring the third dimension to my descriptive works; they bring hyper-realism. They make me think in three dimensions now, which was not the case until recently.”

In fact, Steyer contends that the 3D models increase the accuracy of his and other scientists’ reconstructions because they provide much more information than can be obtained from a 2D model. “CG gives movement, speed, and rhythm to the reconstructions,” he explains. “Fossils, by nature, are static, dead animals. CG goes far beyond the simple 2D reconstructions we built before; it now allows for 3D animations in which we can model and observe anatomical changes during the development of a species and during their evolution, through 3D morphing. Thanks to the medium, we also reach 3D anatomical structures that were unavailable before. We can go inside the bones to see and reconstruct bone tissue, or inside the skulls to reconstruct the brain.”

Present Tense
In just a few short years, Lorrain and Boulay have brought an entire bestiary back to life. For Lorrain, the main purpose of these 3D re-creations is to faithfully represent species that no longer exist. “This is not a static process,” she says, “new discoveries are constantly being made in paleontology.”

Boulay also views this work as a nod to the past as much as the present and future. “My aim is to make everyone aware of the origins of the existing species, and to enlarge our knowledge about those species that are no longer existent. I also want to inspire people in regard to the future and what it holds in terms of evolution.”

Not long ago, the artists’ 3D paleontological models were presented at the International Congress of Vertebrate Morphology in Paris. Some also grace a new exhibition, Giants of the Past, at the museum.

Without question, the role of CG within the scientific community of paleontology is growing. At the museum in Paris, for example, two other specialists have initiated 3D departments, aware of the possibilities that digital technologies can offer in their research. “With today’s 3D tools, the divide between the arts and sciences has been lessened,” Lorrain notes. Presently, Steyer is in the process of building a database of virtual fossils, reconstructed in 3D, to partly replace and save the fragile originals, which are becoming degraded and damaged from handling and study. Moreover, the digital versions from these collections will be accessible to other scientists on the Web.

Boulay adds: “The digital arts are evolving rapidly. Within the next 10 years, I’m convinced that the projections of 3D images will be visible not only in museums, but will become part of everyday life.” Perhaps they will. After all, that’s what technological evolution is all about.

Karen Moltenbrey is the chief editor of ComputerGraphics World.