The Science of Paleoart

Have you ever looked at a fossilized bone, then at a colorful mural depicting the diversity of prehistoric life and wondered how scientists get from one to the other? Julius Csotonyi – and many other paleoartists like him – work with scientists and information from their latest discoveries to bring fossils to life for visitors to museums around the world. Csotonyi created the stunning mural on display in Dinosaur Mummy CSI: Cretaceous Science Investigation – a work of paleoart that presents a vivid look into the life of Leonardo, a brachylophosaurus who died, mummified, fossilized and  – 77 million years later – gives us an unprecedented peek into what made dinosaurs like Leonardo work. Here, Csotonyi shares how he created this gorgeous work of science-art.

An occasional quasi-reptilian hiss of foam and the primordial roar of the bean grinder punctuate the constant brewing of conversation and coffee. The sounds of the cafe form a stimulating sonic backdrop to the dance of stylus on drawing tablet as the digital portrayal of a prehistoric landscape slowly takes shape on the glowing LCD display in front of me. The life of a paleoartist has changed a lot since the days when Rudolph Zallinger slaved away for years on his monumental “Age of Reptiles” mural on 110 feet of wall space in the Yale Peabody Museum.

Although my choice of work setting is probably not typical of most in my field, my local Canadian cafe on Winnipeg’s lively Corydon Avenue serves as an inspiring setting, keeping me supplied with stimulating servings of java and occasional breaks for friendly human contact. However, the relaxed setting conceals an undercurrent of focused work (bordering on the obsessive, even, as my friends will no doubt tell you) and tenacious network of interdisciplinary cooperation on which restorations of prehistoric life have always been based. Passersby who glance over my shoulder at my developing digital illustrations often ask how I know how to depict these creatures of a bygone era. I’m sure they often leave with the profound relief of having escaped mostly intact, and the regret of having asked such a seemingly innocent question. And now that I have your undivided attention…

Digging Science that Rocks

It all begins with a rough sketch. No, back up. It all begins with the team member of a paleontological dig spotting a fossilized bone sticking out of the ground. Fast-forward through the veritable blood, sweat and tears of painstaking work to recover and prepare the marvellously preserved fossil, which yields a boon of information. Next comes the time to share the exciting discovery with the rest of the world; in this case, in the form of a special exhibit at the Houston Museum of Natural Science.

To the Drawing Board!

Enter the paleoartist (a term coined by paleoartist Mark Hallett to describe an artist who specializes in restoring prehistoric organisms.) Although the displayed fossil will certainly speak for itself (in the “oohs” and “ahs” of entranced museum visitors,) it is my job to help fill in patrons’ imaginations of what it may have been like to stand on Montana’s floodplains 77-incomprehensible-million summers ago to gaze at a landscape no human being will ever be able to photograph. As a dinosaur enthusiast, I am awed by the thought of the sight: huge birdlike reptiles ambling along the hot, humid riverine landscape amid stands of redwood-like trees and fern thickets, stalked by stealthy bipedal predators, barely glimpsed as fleeting wraiths in the shadows. My intent is to try to open as realistic a portal as possible to such a vista. This effort requires keen attention to detail and close collaboration with scientists, museum exhibit designers and project managers. Far from simple guesswork and reliance on imagination, the process of creating a scientifically accurate mural for a museum involves not only artistic skill but also interdisciplinary cooperation. On this whirlwind tour of such a project, I will therefore gloss over most of the artistic techniques involved, and focus instead mainly on the process of incorporating scientific knowledge into the artistic endeavour.

To the drawing board, then. I began with discussions with Joe Iacuzzo (Leonardo Project manager with the Judith River Foundation) and Lex Vanderende (exhibit designer at the Houston Museum of Natural Science) who outlined what they had in mind for the layout and content of the exhibit: the number of illustrations, their preliminary sizes and their general foci. Their experience and advice were invaluable to help me plan out images that will capture people’s interest.

A paleoartist must use reliable reference material for their restorations. Therefore, I first read scientific articles on the animals, plants and geography that a time travellor would encounter if they were to visit the Campanian (a time period during the late Cretaceous) in Montana, where Leonardo, the Brachylophosaurus that is the star of the show, was found. Several search engines exist for obtaining scientific publications; although many are accessible mainly through university library systems, a reasonably good one that is available to the general public is Scirus. One can direct it to search only within journal articles, several of which are available freely on the web. Numerous emails and telephone conversations with experts such as David Trexler (paleontologist with Montana’s new Great Plains Dinosaur Museum)  and Dr. Bob Bakker (Curator of Paleontology at the Houston Museum of Natural Science) were invaluable, for they helped complement my knowledge with relevant paleontology, and they shared exciting new research results. Visits to museums such as the Royal Tyrrell Museum of Palaeontology to observe articulated skeletons of relevant species from various angles also helped.

Roughing It

My scientific background came in handy during image planning. I am trained as an ecologist, one who studies how animals, plants and microorganisms interact with each other and with their environment. This background helped me to plan the layout of the mural in order to maximize its educational value by illustrating numerous ecological concepts. Although my role in this project is principally as an artist, I also helped to write the museum’s interpretive text for the illustrations.

Now that I had a mental image of the environment that I wished to restore, I drew rough sketches of the proposed layout for each illustration. These sketches showed just the planned positions and poses of animals and plants. Computer technology greatly facilitated the creation of these rough sketches, as well as the subsequent tennis match of review-and-revision that ensued between the paleontological experts and me as the roughs were perfected. I created all of my work digitally using a stylus and drawing tablet connected to a computer that runs graphics programs. In this way, revisions were easy to make, which greatly sped up the process. I posted revised images daily on my website, on a special page accessible only to exhibit team members, and this precluded the need to actually shuttle back and forth between the experts. It also allowed them to conduct their reviews of my work within their own schedules.

Fleshing Out the Dinosaurs

 

Once the layout of the rough sketch was finalized, I began the process of rendering the images in full detail. Anatomical accuracy was paramount. I began with a carefully proportioned drawing of the skeleton of a dinosaur (e.g. the Brachylophosaurus, illustrated here), which was based on reconstructions of dinosaur skeletons by palaeontologists. I then fleshed out the skeleton, outlining the body’s shape as defined by organs and muscles. How do I decide where to place dinosaur muscles and what shapes to draw them?

Palaeontologists decipher the scars on dinosaur bones to interpret where and how many muscles were attached to those bones, while comparisons with the muscular systems of living animals suggest how those muscles likely pulled bones against each other to allow the animals to move. Published scientific articles helped, but palaeontologists involved in the project also created custom sketches of inferred muscle configurations for me to use as reference, based on the most up-to-date research, ensuring that accuracy is maintained to the best of current knowledge. Also, the mummified dinosaur in this exhibit, nicknamed “Leonardo,” is so complete that some of its muscles are actually preserved in full relief, making their restoration even easier.

After delineating the musculature, I painted in the dinosaur’s skin. The exciting thing about a fossil such as Leonardo, the Brachylophosaurus at the heart of the Dinosaur Mummy CSI exhibit is the superior level of its skin preservation – nearly 90% of its skin texture is fossilized, for which it holds a Guinness World Record! This allowed me to accurately depict the different textures of scaly integument on each part of its body. Because I painted each and every scale, the process was quite time-consuming and required considerable patience. Lots of coffee on hand also helped, for which I thank the talented baristas of my local cafe on Corydon Avenue!


Plants: More than Just a Backdrop

It is just as important to accurately portray the vegetation and landscape in a mural as it is the animals. I needed to be careful to depict only the groups of plants that palaeobotanists (scientists who study plants from extinct ecosystems) have found in the relevant geological formations. For example, I avoided including anachronisms such as lawns of grass; terrestrial grasses appear to not have yet evolved in North America 77 million years ago, and the land was instead dominated by ferns, horsetails, conifers and other relatively primitive plants and also a few early flowering plants such as magnolias.

However, reed-like plants did inhabit waterways. So it is important to exercise care not only in the types of organisms to include in an illustration, but also in their placement within the landscape. So much is known about the plants, animals and landscapes of this prehistoric setting that I could visually reconstruct the ecosystem with considerable confidence. Indeed, with the wealth of knowledge that palaeontologists and palaeobotanists communicate to paleoartists these days, we see increasingly careful attention to detail toward placing dinosaurs into their correct ecological contexts.

A Paleo-Photo Shoot

Finally, one of the greatest benefits of digital media in paleoart today is that it allows the creation of images with a truly photorealistic feel, bridging the gap between imagination and reality more completely than ever before. Furthermore, the completion of a 64-foot-long museum-quality mural in only a few months was only possible because of the high efficiency of techniques such as photographic compositing.

To create the main outer chamber mural with a photo-realistic feel, I packed up my digital SLR camera and travelled to places with appropriate plant species and landscapes, such as estuaries (where rivers meet the ocean, e.g. Cowichan Bay) and humid forests (e.g. Cathedral Grove). From the thousands of photos that I shot (under appropriate lighting conditions, I had planned out in the rough sketch) I extracted the necessary components, such as plants, and combined them in new ways that were consistent with Leonardo’s landscape. Although not all the plant species are exactly the same as existed in the Mesozoic, I still took care to keep the major groups (e.g. ferns) correct. In some cases, even the genus of a plant was accurate (e.g. Metasequoia, the dawn redwood, the dominant tree in Leonardo’s habitat). Once the landscape was thus prepared, dinosaurs were added by a combination of painting and compositing.

Throughout the painting and photographic compositing process, I was continually open to palaeontologists’ suggestions for revision. The end result is a painting that comes as close to restoring an ancient environment as it is currently possible. The digital medium in which I created it also ensures that the image may be easily updated as new information outdates some aspects of it. This would have been more difficult to do with traditional (non-digital) illustration techniques.

In the meantime, I hope that visitors to the HMNS will enjoy the exhibit!

Julius T. Csotonyi is a paleoartist and wildlife artist with an incurable enthusiasm for dinosaurs. Working closely with paleontologists, he has created the murals for the current HMNS special exhibit, “Dinosaur Mummy CSI: Cretaceous Science Investigation.” He has also produced work for several museums, such as the Royal Tyrrell Museum of Palaeontology, and publishers, such as the National Geographic Society. He maintains an online gallery of his workJulius is also trained as a scientist, with a M.Sc. in Ecology and Environmental Biology, and is currently completing a Ph.D. in Microbiology. When he is not illustrating wildlife, he now researches and lectures about the ecology and physiology of bacteria from weird and wonderful places such as deep ocean hydrothermal vents and colorful terrestrial springs twice as salty as the ocean. In this blog, he describes how he incorporated scientific knowledge into the creation of the HMNS exhibit illustrations.

Spirits & Skeletons & Steve

Trick Or Treat Smell My Feet
(Magic) trick or treat at
Spirits & Skeletons at HMNS!
Creative Commons License photo credit: peasap

Steve Wallach has been performing magic since he was 10 years old. He’s not your average cheesy magician you see at a neighborhood children’s birthday party, either. Steve has made a career out of traveling around the globe and performing illusions for CEO’s, charities, country clubs, and luxury resorts.

I met Steve when I was invited, impromptu, for a meeting about a potential event we were considering for Body Worlds 2. Steve looks like he’s easy-going and from the moment you meet him you can see he’s incredibly observational and is absorbing every detail about you he can take in. As we all sat down to the table, Steve offered to give the four of us a demonstration of his skills. He picked out my co-worker Jason, who was also invited to the meeting impromptu,  and requested that he think of an address from a house he had growing up. Jason recorded the information on a piece of paper while Steve was facing the opposite direction. Steve then asked Jason to think very hard about the address numbers and then proceeded to write something down on his own piece of paper. When both of the papers were lined up next to one another, they read the same numbers on each sheet.

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Magician Steve Wallach
(not pictured) 
will amaze you!
Creative Commons License photo credit: cainmark

As Steve’s show continued, he told me about an accident I had when I was 8 years old and was learning to ride a bike. I had careened into a cement block that busted my knee wide open. Then we opened up a travel book off of a shelf and Steve started spouting off names of the islands that were listed on the page from across the room.

I’m sure I sound crazy right about now, but cross my heart, I saw it all! Working at a Science Museum, sometimes it’s tough to believe that some things don’t have a rational explanation. Or sometimes they do, but Steve Wallach isn’t about to give away his secrets!

See Steve Wallach in all of his glory during Spirits & Skeletons this Friday night from 8pm – 12am and let him boggle your mind. Don’t miss out on the IMAX, Etoile Arabesque Belly Dancers, Fatima and her palm readers, cash bar, or lite bites either. It’s a night full of mystery, illusion, and fun at the best Halloween party in town! Buy your tickets now ($15 non-members, $13 members) this party is sure to be packed!

Creepy Critter Cameo – Caecilian

Smoke Tinged Halloween Moon
Creative Commons License photo credit: peasap

Halloween is by far my favorite holiday.  I love that everyone, young & old alike, can dress up as just about anything from the classic witch to the random Roman column I spotted at last year’s Spirits & Skeletons.  Each year is a new opportunity to unveil yourself as a superhero, an Indian princess, a mad scientist, or even a hideous monster. 

Let’s focus on this last costume – the monster – the creepy, skin-tingling costume that never fails to invoke fear deep within us.  Why do we insist on wearing a scary costume?  Humans (and animals) have instinctual fears, a natural survival technique to avoid possible near-death situations, which includes dangerous animals.  Perhaps by dressing up as these scary beasts we can overcome our fears. 

Where does the inspiration for these beasts come from?  From nature, of course!  We see films or photos of animals in real life and can create a whole new monster with the help of our highly over-active brain, especially when watching a scary movie alone, at night, in the dark, with a full moon out, and possible werewolves ready to pounce at any moment!  Yikes!  Let’s take a look at one creepy critter that resides here in the Museum – the super-slimy Caecilian!

We have a Mexican Burrowing Caecilian (pronounced sə-sĭl’yən) , Dermophis mexicanus, a legless amphibian from the order Gymnophiona.  They live underground in Central Mexico and can grow up to 2 feet long.  Their diet primary consists of small invertebrates, including termites and earthworms.  After an 11-month gestation period, they give live birth (most amphibians lay eggs) to between four and eleven young.  When presenting this amphibian to students, we discuss how is it different from other vermiform animals such as worms and snakes.  The kids usually determine that it has a backbone (worms are invertebrates) and that it is slimy, not scaly (reptiles have scales and are not slimy).  Our caecilian is a very shy, quiet animal that also happens to enjoy attempting great escapes.  I think it’s a rather cute amphibian!

Our Mexican Burrowing Caecilian

There are over 150 species of caecilians, ranging along the tropics from South America to Africa.  They may be a dull grey or brown or even brightly colored purple, pink, orange, or yellow.  Most lack tails and all have tentacles, a specialized chemosensory organ near their nose that helps them to locate prey.  Many caecilians are nearly sightless, some without any eyes at all.  They may be aquatic, terrestrial, or fossoriallike our Mexican Burrowing Caecilian.  Depending on where they live, caecilians may be oviparous (egg-layers) or viviparous (live-bearers). 

Warning!! Here comes the creepy flesh-eating part of our story!!

In the womb, the developing caecilian embryos have specialized fetal teeth that allows them to stimulate secretions from the oviducts of their mother, providing the young with nourishment.  In another species, Boulengerula taitanus, an oviparous caecilian from Southeastern Kenya, the newborns also have specialized teeth to eat the skin off the back of their mother!!  The skin is regenerated every 3 days for the young, providing a nutritious meal.  Research has also found that a female may take care of young that aren’t biologically hers, a term called alloparenting.  However, this is a costly to the “nursing” female.  Check out this BBC video to experience these flesh-eating, super slimy critters in action.  Truly a fascinating animal worthy of mention at Halloween.

Boulengerula taitanus

To see more super scary, awe-inspiring yet repulsive critters for the Halloween season, check out this fun blog I found while researching tigerfish and then again while looking for caecilians: Ugly Overload! 

A Trick or a Treat?

In less than a week, people all over the country, including right here at our museum, will be celebrating Halloween. Perhaps your workplaces and schools are already festooned with ghosts, skeletons, graveyards, and the like.  If you stop and think about it, you may wonder just how it is that we came to celebrate by trying to disguise ourselves or by trying to frighten people.  Is this a trick or a treat?

Picket fence and yellow trees
Creative Commons License photo credit: joiseyshowaa

The short answer as to why we celebrate this time of year with images of death is that we are in the middle of autumn, the season when nature itself is dying.  To fully understand why we celebrate Halloween when we do, we must fully understand the seasons.

Earth orbits the Sun with its axis pointed at the North Star, Polaris. As a result, its axis is tilted by about 23.5 degrees with respect to its orbital plane.  This tilt, combined with Earth’s revolution around the Sun, causes the seasons.  If the North Pole leans towards the Sun, the Sun is higher in our sky and we get more direct sunlight.  Also, daytime is longer than nighttime.  As the North Pole begins to tilt away fron the Sun, the Sun appears lower and lower across the sky, and daytime gets shorter and shorter.  Eventually, the slanted-in solar rays and short days bring about winter.  Very cold air masses form in the darkened Arctic and begin to move south, some of which can even reach Houston.

Keep in mind that the Earth’s axis does not tilt back and forth; it points at Polaris the whole time.  In June, the North Pole is leaning towards the Sun, but by December, the Earth’s motion has carried it to the other side of the Sun.  The North Pole, still tilting the same way, now leans away from the Sun.

A common misconception is that the Earth is closer to the Sun in summer and more distant in winter, and that is what causes our seasons.  In fact, Earth’s perihelion (closest approach to the Sun) occurs just after the new year (January 1-4), while aphelion (greatest distance from the Sun) occurs around the 4th of July.  Earth’s orbit is an ellipse, but the Earth-Sun distance does not change by enough to affect our seasons.

where are you?
Creative Commons License photo credit: shioshvili

In the cycle of seasons, there are four points of note.  At the March equinox, neither pole is tilted toward the Sun and the Sun is directly overhead at the equator.  The is the vernal (spring) equinox for us and the autumnal (fall) equinox for folks south of the equator.  At the June solstice, the North Pole is tilted as much as possible towards the Sun, and the Sun is overhead at 23.5 degrees North (the Tropic of Cancer).  This is the summer solstice for us and the winter solstice in the Southern Hemisphere.  At the September equinox, once again neither pole tilts toward the Sun, and the Sun is again overhead at the equator.  This is our fall equinox and their spring equinox.  At the December solstice, the North Pole is tilted as much as possible away from the Sun, and the Sun is overhead at 23.5 degrees South (the Tropic of Capricorn).  This is the winter solstice for us and the summer solstice below the equator. 

We generally think of these points as the beginning of spring, summer, fall, and winter, but it doesn’t have to be that way.  After all, nothing magically happens with our weather on these dates.  We could just as well consider these points the midpoints of each season.  In that case, the seasons would begin and end at points roughly halfway between the equinoxes and solstices, in early February, May, August, and November.  If the equinoxes and solstices are ‘quarter days,’ the points halfway between them become the ‘cross-quarter days.’

The ancient Celts of Europe appear to have divided their year in precisely that way.  Gauls living in what is now France used a calendar of twelve lunar months with a 13th month added every 2.5 years (similar to the Hebrew calendar today).  Their two most significant months were Gamonios (lunar month corresponding to April/May ), which began the summer half of the year, and Samonios (lunar month corresponding to October/November) which began the winter half of the year.  Julius Caesar noted that daytime followed nighttime in Celtic days.  By extension, the dark (winter) half of the Celtic year preceded the light (summer) half, making Samonios the start of their new year.

The Celts in the British Isles (Irish and Scots) also had festivals aligned with the cross-quarter days.  In early February was Imbolc (or St. Brigid’s day).  Weather predicting traditions of this day are preserved in our current Groundhog Day.  Traditional May Day celebrations are similar to those of the Celtic BeltaneLughnasadh, in early August, marked the start of the harvest. 

'' The Sentiment of Light''
Creative Commons License photo credit: jdl_deleon

The most important, though, was Samhain (pronounced ’sah win’, not ‘Sam Hane’, due to rules of Gaelic spelling), in early November.  This three-day festival marked the beginning of the winter half of the year and the start of the whole year, like Gaulish Samonios.  It was the close of the harvest opened at Lughnasagh, and the time for culling excess livestock.  At this time, the veil between the living and the world of the dead was considered thinner than usual, and people looked forward to meeting and communing with ancestors and relatives who had died.  A ‘dumb supper‘ was set aside for departed relatives.  To scare away unwanted spirits, people dressed in frightening garb.  Note that these spirits were considered unpredictable and possibly mischievous because they were not the familiar ancestors–not because they were particularly evil.  Divination was also practiced at this time, as people sought to predict whom they would marry or how many children they would have. 

Doing the math, you’ve probably figured out that Halloween is not quite halfway from the equinox (September 22) to the solstice (December 21).  But remember, the Celts used a lunar calendar.  They celebrated their festivals on a certain phase of the Moon, possibly full moon, occurring nearest the cross-quarter day.  Upon the adoption of the Julian calendar, which was not strictly lunar, the festivals were moved to the beginning of February, May, August, and November, although this meant they were no longer exactly on the cross-quarter days. 

Saint
Creative Commons License photo credit:
The Wandering Angel

In the eighth century AD, Pope Gregory III moved the church’s commemoration of the souls in heaven (All Saints’ Day) from May 13 to November 1.  Another name for All Saints’ Day is All Hallows Day.  (’Hallow’ is an older term for ’sanctify’ or ‘make holy.’  Think of ‘…hallowed be thy name’ from the Lord’s Prayer).  The next day became All Souls’ Day.  The day before All Hallows Day or All Saints’ Day is All Hallows Eve, or Halloween.  The traditions of Samhain, with its similar focus on honoring the dearly departed, were a natural fit for All Hallows Day and All Hallows Eve.

Halloween, then, is ultimately just one expression of the human need to come to terms with death as a natural occurence and to honor those who have gone before.  In the season of the fall of the leaf, with the Sun taking a slightly lower path across the sky each day, the natural world is going through its own ‘death,’ providing a perfect context for our own activities.  We can therefore think of Halloween itself as a treat, not a trick.

I wish everyone a Happy Halloween, with many more treats than tricks.