(continued)

Q: Is there anything that makes the Sarcosuchus project stand out?
A: Most of the bones I carve differ in size from the casts that Paul sends to me. So although I'm always using simple math, there was much more math with Sarco.
With the other animals I've worked on with Paul - Jobaria, Deltadromeus, Suchomimus - we didn't have modern bones to work with, so I wasn't burdened with trying to scale up exactly from one to another. The problem with this giant crocodile was how would its huge size affect the shape of its bones. Would they look just like small modern croc bones greatly enlarged or would they differ in shape, in addition to being much larger because of Sarco's massive proportions?

Paul and I spent a long time with Sarco going back and forth trying to figure out how to scale up bones of the modern American Crocodile to the size of the missing bones of the Sarcosuchus. I had to recarve more Sarco bones than all the other animals combined because Paul was pushing me to be really precise.

Q: What do you need to do in order to "scale up" a bone?
A: The problem is that as an animal grows, not all parts of its anatomy grow at the same rate. The proportions change. That's why if you make a picture of a baby's face the same size as a picture of an adult's face, you still recognize the baby. The proportions are different.

An adult crocodile femur (thigh bone) might be 3 times longer than a baby one but it may be 4 times thicker. Not every dimension of a bone need necessarily increase at the same rate.

Q: What are your "tools of the trade?"
A: They're pretty simple. I use foam for carving. It's normally used for industrial purposes to insulate duct work. I usually order a "full bun." A bun is 8-feet long by 4-feet wide by 28-inches thick. The foam comes in different densities, each color-coded. My personal color of choice is salmon, which has a 2-lb density. That is, a block that is 1-foot cube has a weight of 2 lbs. It's rigid and crispy. You can rasp it away and it crumbles. It doesn't spring back like sofa cushion foam!

I use a wood saw to cut big sections of foam, and rifler files for the finishing work - they're coarse-tooth files used by wood carvers. I also use tools a potter would use to trim clay -a metal loop that has a flat blade you can sharpen is fastened to a wooden handle.

Photo © Stephen Godfrey

Q: Do you use glue?
A: No! I hate that. When you glue something, the rigid glue-line interferes with the sculpting.

Q: Do you have special safety equipment?
A: I get covered with a pile of foam when I work, so I do wear protective clothing- long sleeves, rubber boots. I also wear a respirator because when you're shaving foam for hours you're creating fine particles. I don't wear glasses, but if a fleck gets into your eye it really hurts.

Q: What is fun for you about this kind of work?
A: I really enjoy carving the bones. I love seeing the finished product and thinking "I did that?" PAST does a superb job of articulating these things. The money is good, not to mention the fact that it is very gratifying to work for Paul and seeing the results on display at National Geographic in Washington.

Q: What elements are you working on?
A: Most of the skeleton apart from the skull and scutes.

Q: Is there a sequence to the way a skeleton is built?
A: The order comes as a result of the sequence in which PAST needs to receive the bones. They always start with the pelvic girdle (hips) and the hind legs and the rest of the animal grows from there.

Q: What elements are most difficult to do?
A: Vertebrae [backbones] are much more difficult than leg bones - they take a long time. They are complex three dimensional structures. The facets on one vertebra need to match up with receiving facets on the next vertebra. I can't carve vertebrae in isolation - you have to carve them so they work together. I work carefully because I hate breaking bones and I hate starting over! But I have been known to use five-minute epoxy.

Sarcosuchus axial column, van shown for scale
Photo © Stephen Godfrey

Q: What happens to the foam bones after you sculpt them?
A: I crate and ship them to the Dino Lab at the University of Chicago where molds are made of the sculpted bones. The foam bones are not used in the final mounted skeleton. Fiberglass casts are made from the molds. Although the foam is rigid, it is much too soft to withstand the mounting process, shipping, and handling for any length of time; thus the necessity to make molds from which fiberglass casts are made.

Q: What do your kids think about what you do?
A: It's nothing unusual for them. I think they take it for granted. It's what Dad does. I do take them to the press conferences at National Geographic. I like to have them exposed to that.

Q: Any projects on the horizon?
A: I don't actively look for other contracts; I've got full time work as a curator. The sculpting is extra for me - but I'd work on another project with Paul if he'd have me.

Q: Is there anything you've learned from your own career path that you think is important to share with other people?
A: At an early age I had a predisposition to art but I didn't take it that seriously, and certainly never in my wildest dream imagined that some day, I'd be carving the bones of extinct animals. I think people go through life with abilities that they might not know they have. Or sometimes the abilities are peripheral and they don't know how much they could improve if they pursued them. If you're gifted in an area, you excel more quickly in that field than those who are gifted in other areas. That is why it's important to be exposed to many different educational experiences! That way you have a better chance of finding your place in life.