Exhibits at the American Museum of Natural History sometimes tell their story through specimens, artifacts, and other material from the scientific collections. More often, though, lifelike models, dioramas, and other replicas are used. In addition, photographs, videotapes, and computer interactive and multimedia displays provide information and interest. A large group of people, most of them specialists in different media and techniques, work behind the scenes to make the exhibits that are seen by the public.
We asked Barrett Klein, a preparator and display maker in the Museum's Exhibition Department, why so many of the displays use replicas.
"Many people have asked me why we make the fake things. Is it a game, a test, a challenge to viewers? Why not use the actual specimens?
"There are a number of reasons. First, if we put a real specimen in a display, whether in a glass-enclosed case or a diorama, dermestid beetles will chomp away at it. They go for any organic material. They slip into the tiniest crevices and lay their eggs, and then their larvae destroy the specimen.
"Second, replicas can be made of durable materials, but dried specimens are not at all durable. A butterfly would fade and get dusty. If someone tried to brush off the dust, the delicate wings would be damaged and eventually might disintegrate. Aside from butterflies, many other specimens lose color through fading. For example, the hourglass marking on a black widow spider tends to fade when exposed to light, and soft-bodied specimens shrivel up."
But don't specimens in collections suffer the same problems? Barrett said that these specimens can be stored and preserved in ways that keep them suitable for scientific study but that would not be satisfactory for public display.
"Specimens in collections for study don't need to look as though they are alive. A systematic collection of arthropods, for example, consists of cabinet after cabinet of specimen boxes filled with carcasses with stakes driven through them. The legs are in various unnatural positions and the wings pinned out so everything is visible for study. The bodies may be shriveled. Sometimes the organisms are floating in jars full of preserving solution. Birds and mammals are usually preserved in collections as study skins and separate skeletons. And plants are preserved as pressed and dried herbarium specimens, which do not look at all lifelike. All of that is fine for scientific study. For public display, however, the illusion of life is important," Barrett explained.
Barrett said that an exhibit of specimen cases can be effective in some circumstances, but displays of organisms in their habitat are an especially good way to educate the public. "For that, dioramas filled with replicated plants and animals are the way to go. If these types of exhibits are successful, people will assume they're real. What we're aiming for is not to make the visitor say, 'Oh, wow!' but to say, 'Oh, well.' The goal is not to make visitors feel awe at the creation of illusion but to fool their senses so they think what they're seeing is real."
He showed us the many steps involved in making an arthropod replica, which begins with a real dried specimen. He removes the legs, antennae, and other delicate structures (such as wings from flies or butterflies) that would not survive the mold-making process. He makes a two-part silicone mold, which he uses to make a plastic cast of the body. It is a time-consuming process using materials Barrett and others have developed or modified to suit the desired result.
"That's what I love most about this job," Barrett said. "Most of these things have never been done before. A good chunk of my job is experimenting with methods and materials. For example, I am currently working on three new methods of representing not only insect wings but also legs, antennae, and mouthparts.
"I experimented with wire of different thicknesses," Barrett told us. He also tried making separate molds and casts for the legs. "As for the wings, there are a couple of different methods. The one I chose depended on the type of wing and, to a degree, how far the model is from the visitor. If I'm aiming for a convincing effect of, say, butterflies off in the distance, I can take actual wings and make color photocopies of both sides. Then I score along the veins so they pop out a bit, glue the two sides together, and then paint them. The color on the photocopy is really just a guide, since the process creates a surface that is too shiny and might fade with time.
|Making Models for the Rain Forest
Barrett worked with two other preparators to create models of all of the arthropods and herptiles (reptiles and amphibians) in the Central African Republic rain forest diorama, which is the centerpiece of the Museum's new Hall of Biodiversity. "The mammals and birds are all taxidermy mounts--stuffed skins, basically--but we did all the fake animals," he told us. In addition, there is a wall of 700–800 life-size models to represent the awesome range of biodiversity in the world today.
"We made molds of spiders and myriapods (many-legged creatures, such as millipedes and centipedes) and, of course insects, including true bugs, beetles, hymenoptera, butterflies, and more. In all, there are models of between 300 and 400 arthropods, representing more than 60 different species, and more than 60 models of herptiles representing at least 14 species," Barrett said.
"There's a method I like better for butterflies and moths, but especially for insects with transparent or translucent wings, like grasshoppers, mantids, cicadas, wasps, bees, and flies. I make them with a vacuum-form machine, the same way leaf cookies are made into leaf replicas. You get great resolution that way, with every bit of veining coming through."
Barrett is a fanatic about accuracy, and that carries over to how replicas are placed in the diorama. An entomologist as well as an artist, he researched all of the organisms he has replicated to be certain their place in the habitat is true to nature.
"Some need very specific positions," he told us. "For example, beetle grubs have to be in something that has recently been dug up by a mammal, a rotten log, perhaps. Dung beetles have to be on elephant dung. I have butterflies lapping up water from puddles." He pointed to model in the diorama. "That parasitic fly is about to suck the blood of one of the ungulates. Very little of it is visible since it is be buried in the fur of the mammal." After all that work to make it look real? As far as Barrett is concerned, it is well worth the effort.
Two other preparators who swear by accuracy are Joyce Cloughly and Marco Hernandez. They built dioramas for the Museum's Endangered! exhibit and also worked on the rain forest diorama for the Hall of Biodiversity. We asked them how work on a diorama begins.
"The first thing to do is make a detailed scale model," Joyce said. “After collecting, that's probably the most important thing to do. If you make it to scale, you really get an idea of the problems you may encounter in a full-size diorama. You work out those problems in the model so when it comes to doing the real thing, there's no guesswork and no unpleasant surprises. The last thing you want is have to redesign things at that late point."
According to Marco, the model is like a blueprint of the diorama, and a lot of time is spent making it. "You get answers to all your questions about positioning of objects, how many of each thing you need, and where the light is coming from. If you're still asking questions about sun and shadows when you're installing the life-size diorama, forget about it. You might as well stop right there and do a model to work those things out."
Marco advises model makers: "Make it well and make it durable, because exhibits come and go, and the model may be the only record of how the exhibit looked."
|Baking Cookies, Museum Style
Vacuum forming is a technique used to make many copies of something--leaves, for example, or insect wings--from a plaster mold. Alec Madoff explained how leaves are made by this method
"After the original leaf has been painted with many thin layers of plaster, the plaster mold resembles a cookie with a leaf impression on one side. These 'cookies' are embedded in a plaster block, and hundreds of small holes are drilled through the plaster around each leaf. The mold is then placed in a vacuum-forming machine. A sheet of clear acetate is placed over the block and is softened using a heating element. When the acetate starts to sag, you push a button that creates a vacuum by sucking the air down through the tiny holes. That pulls the acetate against the mold. It hardens in seconds, and then you pop off the sheet." The result is a sheet of perfect replicas of the original leaves.
Hundreds of thousands of leaves were made this way for the Central African Republic rain forest diorama, requiring teams of volunteers to spend untold hours carefully cutting them out of the sheets.
"It's very labor intensive," Alec said. "Every jagged edge and every curve has to be preserved." The edges are then sanded, and wires are attached to the rib lines of the leaves. "Then the leaves are individually painted on both sides with an airbrush, and then someone else goes over the leaves to burn in insect holes and make other imperfections so the leaves look natural. Leaves that are too perfect just don't look real," Alec said.
Insect wings also need to be cut out carefully. Then they are painted in colors and patterns that accurately mimic those found in nature. Finally, they are attached to the replicated body.
Aside from replicas of plants and taxidermy mounts of animals, dioramas contain landforms such as hills and cliffs, rivers and ponds, rocks and possibly even features made by people. The backgrounds are painted on curved walls to give depth to the diorama so viewers feel as if they are looking out on a landscape through a window.
The formula and technique for achieving convincing perspective on a curved background wall are very complicated, Joyce said, but basically the artist needs intentionally to distort the painting so that it looks correct from the position of the viewer. A bison on the side of a diorama, for example, must be painted much wider than it actually is so that it doesn't look too narrow when viewed from the outside. If the viewer could climb inside the diorama, however, and look at the bison straight on, it would look unnaturally bloated.
Marco's talent and his art school training came in handy when he made the panda diorama for the Endangered! exhibit. "I made the landforms with a wire framework and wood, which was covered with burlap and then plaster. I had to do that first, before I began painting the background. I started out with a charcoal sketch of the landscape on the canvas. I composed it so the three-dimensional landforms in the diorama ran right up to where the canvas began. It was a real challenge to get it right."
Another kind of display used in exhibits at AMNH relies on mounts holding objects inside a display case. Alec Madoff is a master mount maker, and we talked to him about his work.
"A mount is really just a piece of material--usually metal--that holds an object or artifact. The idea is to hold it securely in a position that shows what should be shown without damaging the object or drawing attention to the mount."
Alec has made mounts for objects as diverse as Peruvian pottery, Northwest Coast Indian masks, and, most recently, precious gems and priceless jewelry for the Nature of Diamonds exhibit at the Museum.
Joyce Cloughly told us about some of the materials they use at the Museum for making diorama models:
- nonhardening clay
- epoxy putty
- two-part epoxy: when it hardens it makes very convincing-looking water
- wire for armatures
- twigs: these can make nice-looking trees
- chopped up leaves: for leaves
- human hair, bristles from brushes: for grass
- paint: acrylics, or casein for a less shiny surface
"We usually use brass, which can easily be bent to shape, and then cover it with plastic tubing or paint so that oxidation of the metal does not mar the surface of the object it is holding.
"Mount making begins with a talk with the exhibit designer about where a particular object will go on display. We also talk with the curator about what part or parts of the object should be visible. Then we talk to someone in the Conservation Department to determine how to protect the piece from damage. We work very closely with conservators, the people who are either repairing or restoring or just making sure all of the objects in the Museum are handled properly."
According to Alec, "The ideal mount is one that is invisible so the object looks as if it is just floating there. We try to use the thinnest possible piece of brass that will still hold it securely. The mount should come around from the back and extend just beyond the halfway point. We taper the end that shows in front so you don't see a hard edge."
Geralyn Abinader makes videos for the Museum. We asked her how she works with the other people who design the exhibit.
"The curator comes up with the idea for an exhibit, then the designer comes up with the different elements, including specimens, models, and videos. After they decide on a concept for the video, I meet with the designer, to find out how he or she envisions the video fitting in with the whole design, and the curator, to define the content, what the point is, what its purpose will be.
|Some Mounting Tricks and a Tricky Mount
Alec Madoff told us about some special mounting strategies he has worked out in the past.
- To show the back side of something, place a mirror in the case so the back or bottom of the object can be seen as well as the front.
- If some part of the message or design or some other detail is too small or hard to see for some other reason, have an artist make a drawing of it and add that to the display.
- Kwakiutl transformation masks are a special challenge. These show one face on the outside, and then they open up and show another face. "We wanted to show both, so we had to construct a multipart mount that held the mask open," Alec said.
"There are several different types of videos. There's the story video, which can be experienced on its own and has a beginning, a middle, and an end. There are loops that just show examples of something over and over, and the viewer can catch the show at any point. Often it is something the visitor can't see in any other way: how a particular machine works, a peek into the microbial world, living animals beside a skeleton of an ancestor, things like that. Then there are interviews, which bring people into the exhibit to talk to the visitor about some subject related to the exhibit."
Besides the type of video, what does Geralyn have to think about?
"You have to choose a style that suits what you are trying to accomplish with the video. For example, for the Amber exhibit, we focused on artists in Russia who had spent their lives learning how to carve amber in a traditional way that has almost been lost. We interviewed them and showed them doing their work as a way of respecting their art and bringing it to life. In contrast, we took a much more dynamic approach for Endangered! We were trying to evoke emotions in our viewers, so there were a lot of graphics, special effects, jazzy music, quick cutting--all as a way of getting people involved."
Another important consideration is where in the exhibit the video will be shown. "The location often influences how long the video can be. Surveys have been done in museums to see how long people will stick around and pay attention in various locations. If it's in a main traffic area, people will come by, stop for a few minutes, and then move on. It doesn't matter how interesting it is. So if there's nowhere to sit, it's a good idea to keep your piece down to about three minutes because people don't last longer than that. If it's in a separate sit-down area, the piece can be longer, maybe eight to ten minutes," she said.
"You also have to take into account the type of display and the lighting around it. For example, if the video will be projected on a wall, the image will bleach out unless the area around it is dark. If it's on a video monitor, lights around it may cause glare. LCD screens have to be watched from directly in front, or the image turns negative. It may be necessary to try different locations and different display techniques to get it right," she suggested.
|Making Words Work
Captions, labels, posters, video narration, and other verbal information have a place in an exhibit. It is often necessary to tell as well as show. Exhibition Developer Willard Whitson gave us some tips on how to use words effectively.
"Keep it short; use the fewest words possible," he said. "You have to recognize that visitors breeze through an exhibit. They are not there to read; they are there to look and experience. So your exhibit text should be as eloquent and amusing and engaging and succinct as it can be. It should be jargon free; it should have a minimum of terminology that requires a visit to the encyclopedia and dictionary to get through it. That doesn't mean you can't use words that people aren't familiar with, but if you're going to use them you have to define them. And if you find you're defining every other word, then you're doing something wrong.
"With labels, the main point you want to get across is: 'You are looking at a . . .' Make sure what you're writing is not redundant. That is, if the object is a blue vase, you do not have to say it is blue, but you should say where it comes from and how old it is and what it is made of. If you're showing three beetles, you don't have to say there are three of them, but you should identify them by genus and species."
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