Like any other museum of its kind, the American Museum of Natural History in New York City has emphasized its collections since its modest beginnings in 1869. The very first exhibit is the Hall of North American Mammals, a still zoo of stuffed giants walled behind thin glass. The Hall of Mammals is exactly the type of collection that we have come to expect from a natural history museum; large animals, giants of evolution, captured midway through their most defining behaviors.

But the trend in natural history collection is headed towards breadth and utility rather than enormity and drama. Most of the museum’s collections are hidden from the public, arrays of smaller, desiccated tissues and partial fossils kept sequestered on its basement floors. But even these vast catalogs are giving way to more sophisticated collections capable of holding hundreds of thousands of samples without the disorganization that has plagued natural history museums for decades.

Dr. Rob DeSalle, curator of the invertebrate collections, also directs the Ambrose Monell Cryo Collection, a biological repository of frozen tissues harvested from plants and animals in places as exotic as Africa to places as local as New Jersey. It’s a well-preserved swath of current biodiversity, and because the tissues it contains can be thawed, in a sense it’s far more alive than any of the growling taxidermy encountered by the afternoon field trips. The Ambrose facility and others like it are quickly making relics of the museum’s static, stuffed collections.

DeSalle believes the real power in the Ambrose Collection is that it is cryogenic. Cryogenics has revolutionized the storage of biological samples because the extremely low temperatures involved (often below 150 degrees C) guarantee tissue and DNA viability for an indefinite period of time. In the genomic age, when artificial insemination, surrogate motherhood, and even cloning, have become day-to-day realities, the word “cryogenic” is loaded with possibility.

But DeSalle is a taxonomist who has focused on disentangling evolutionary pathways for nearly 35 years, and he maintains that the Natural History Museum’s cryogenic collection is an extension of the more traditional collections, frozen bedrock over which we can trace our evolutionary history.
Other institutions such as the San Diego Zoo’s Center for Reproduction of Endangered Species (CRES) have been banking sperm and eggs for years, creating a so-called frozen zoo. DeSalle considers the frozen zoo an effort at conservation, distinct from the Ambrose Collection, which merely preserves tissues.

Cloning with somatic DNA – DNA from body cells – complicates the picture and blurs the distinction. Recently, CRES has also begun to archive somatic DNA. A team of geneticists lead by Dr. Oliver Ryder has used the DNA of a banteng calf, an endangered animal indigenous to Java, to clone a new member of the species. "I was floored when I saw the living animal that came from the cells in our freezers," said Ryder. Tissues in the Ambrose Collection could function in the same way. A nucleus from any cell could seed a clone of the source individual. In some sense, the Museum of Natural History, long a collection of dead things, is now very much alive. But can DeSalle see it that way?

I first met Rob DeSalle when he picked me up from the Hall of Mammals, a place he admits he rarely sees. To DeSalle the scientist, the exhibits that give the museum an enduring face, like the mammals or the installations on biodiversity, are its most static and uninteresting features. “On its face the museum seems so organized because the things that the kids want to see never really change.” Unlike the exhibits that net the crowd, the cryogenic collection, established in May 2001, is constantly growing and changing.

The staleness of the Hall of Mammals was obvious in some of the older children’s faces, probably a consequence of too many suburban birthday parties watching the jerky motion of servos timed to happy music at Chucky Cheese. But as we crossed through the Milstein Hall of Ocean Life on our way to the Ambrose Collection, a few of the younger kids actually fell over backwards gazing up at a plastic blue whale that crowns the exhibit, looming large over the plastic ecosystems that sustain it. I followed DeSalle to a little used elevator in the middle of the museum. We went down.

The doors of the elevator opened on the museum’s back end. The hallways were whitewashed and narrow. DeSalle guided me through the passage, limping slightly on his right leg. He’s a burly man with long stray hair, a coarse beard, and a gentle manner. He seems a bit like an animal clumsy on land but swift in its medium of choice. If it weren’t for all the hair, I’d consider him a beached seal. His feet drag on earth, but immerse him in talk of biology, and his mind races.

“The chaos of my department isn’t really my fault. It’s sort of built into the critters we study. The pre-packaged content we provide to the public is neat and trim, but it’s not real,” said DeSalle.

Biology, specifically, invertebrate biology is really messy. Evolution adds on itself and compounds itself, creating redundant organisms with only slight changes. The late Stephen J Gould has written that “the history of life is not necessarily progressive; it is certainly not predictable. The earth's creatures have evolved through a series of contingent and fortuitous events.” The goal of the Ambrose facility and others like it is to catalog this fleeting biodiversity before luck runs out on the most fragile branches of life.

DeSalle runs a kind of salvage operation. It’s as if he sieves the museum’s upper floors and collects the meaningful fragments to freeze down below. He provides a physical and digital home for our dwindling biological information, a pool that’s so vast it’s impossible to know what we unwittingly destroy.

Following DeSalle down in an elevator, down some stairs, and down a hallway that was downward tilting, we somehow arrived at a door that opened to the outside. I half expected a dungeon with lungfish and giant beetles. Instead, we exited the building and passed a liquid nitrogen tank nearly a story tall. He pointed at the ice-encrusted fixtures and stopped just short of where the heavy mist melted into air.

DeSalle understands his facility’s importance in preservation, but like most scientists, half the time it seems like he could care less because it’s the method that really gets him. He’s so into the details of his facility’s operation. “This nitrogen flows directly into our vats on the other side of that wall. Right now we have eight cryogenic vats, each vat containing six sections, each section containing nine racks, and each rack containing thirteen boxes.

Each box contains 100 vials.” He stood there for a minute and let me contemplate the math. I took a moment, staring off into space like I’m sure a good scientist would do, and pretended to contemplate. “That’s 70,000 specimens per vat. That’s 560,000 total specimens,” he said. And that’s a significant chuck of biodiversity held in a facility half the size of the Hall of Mammals.

The absolute numbers are impressive. But what exactly does it mean to have a frozen tissue sample in a vial in a box in a vat? With a giant stuffed grizzly, up on its haunches, at least you know what you’ve got. How useful is a preserved bit of tissue? At the San Diego Zoo, Ryder and his colleagues have shown that a bit of frozen DNA is all you need to invoke the genuine article. It’s easy to hope that the Ambrose collection is more than a sophisticated form of taxidermy.

The collection is many times over the largest such frozen collection in the world, despite its relative youth. So the ultimate dream is revival of lost communities of species. But DeSalle and I had been through that, and when I ask him again, he gets a little annoyed. He insists that the goal is to map biodiversity, not to be the raw material for some Frankenstein effort at rebuilding ecosystems. At this point, any clone of an endangered species would simply sit in a zoo, more a cloning experiment than a real effort at species resurrection.

Dr. Cathi Lehn, a conservationist at the Natural History Museum, believes that a zoo should be a source of information rather than a setting for a complex cloning experiment. “When zoo animals die, more often than not they are simply incinerated. I cringe every time I hear that a valuable animal’s body was destroyed before we could get information from it: skin samples, blood samples, any samples,” she said. The buzzword is “resource.”

In every meeting, with curators at the Natural History Museum, I have heard this word repeated to me at least five or six times. DeSalle believes the facility is a resource for understanding biology and evolution, and until I ask him to be a bit braver, he won’t go any further.

It’s not fantasy to envision a time when we diversify a hopeless mammalian population using the frozen sperm of individuals from hundreds of years before. Cloned males from preserved specimens could do the same job if they’re dealt to suffering populations evenly. And in cases of extinction, Ryder and his people at CRES have already shown that it’s possible to implant frozen embryos into similar host animals, resurrecting a few identical individuals from a dead species through surrogate motherhood. DeSalle acknowledges the pipedream, but holds back.

“I don’t know about a repository for re-creation. Probably not. But it doesn’t really matter. Whether or not it was extinguished by the human species, everything has its time and its place. We’re changing the structure of life trees faster than we probably should, but we were born of it, and we’re definitely not above it. Re-creation is not the answer to extinction. We can’t recreate just because we feel bad. That would be like putting a band-aid on a shotgun.”

The implication is that our destructiveness may just be part of the natural order of things. Why create a technology to rectify something we’re not sure is broken in the first place? Maybe we’ve evolved to wipe the slate clean. It’s hard to stomach this. I was queasy walking between those mammals stuck in pose, I know the zoo glorifies a few token members of one sadly reconstructed ecosystem after another, and this so-called frozen zoo is so abstract and so filled with metal and ice, it’s hard not to feel like part of a steamroller.

DeSalle believes the best way to preserve life is not to bring it back from the dead, but to ensure the environs are left as alone as possible. It’s not a new conclusion. Less educated people have been chanting that bit for years. And it’s pretty conservative for a pioneering scientist in biological storage. DeSalle understands that whatever salvaging he and others like him do is never going to be enough. Because although it may be possible to preserve a portion of an organism once in perfect Darwinian harmony with its environment, it’s impossible to recreate those environmental conditions once they are gone.

Kamaljit S. Bawa, a conservation biologist at the University of Massachusetts Boston, is afraid that technological strategies to restore extinct species might be viewed as a shortcut around the more difficult work of environmental care. Bawa is concerned that genome banking does not meet the conservation criteria of the U.S. Endangered Species Act. Further still, most of these endangered creatures are evolutionary endpoints; they are nothing without their proper biological context. Frozen Zoos, like the San Diego Zoo’s CRES, skim from the very top of the biomaterial pool.

It’s like capturing the Millstein Hall’s blue whale without an eye to all the little plastic meals that teem beneath it. The blue whale isn’t complete (or alive) without the krill it filters from the sea, or the zooplankton that sustains the krill, or the phytoplankton that supports the entire deep-sea web. A specimen of blue whale by itself is so artificial it might as well be plastic. And even if the right conditions could be found, cloned replicates inserted into a re-found Eden will not seed a comeback.

Conservation is as concerned with the genetic health and diversity of a single species as it is with the overall ecosystem. A recreated individual, or even a few individuals of a long-gone species, are more curiosities than viable progenitors. “Even if we could eventually make endangered species in the lab, you still don’t have anywhere to put them,” said Karen Baragona, an ape specialist with the World Wildlife fund in Washington DC.

“If you focus on habitat, you not only protect one species, but hundreds of other plants and animals and the whole complex ecological system. There’s more meaning in that.” Without a population of recreated animals the effort is a waste, and even if you could build a population, a task that might require one of DeSalle’s entire vats, it’s probably a waste anyway because, you’ll have no where to put them. Conservation in this context is always incomplete.

The full weight of this lack isn’t apparent until you actually see DeSalle’s chrome vats. Nothing could be more inorganic. The large structures resemble Apollo landing-pods, complete with a drift of thin white gas along their stainless steel flanks. Dr. Robert Hanner, now at the Coriell Institute, a research and storage facility almost exclusively devoted to the frozen preservation of primate (including human) cell lines, almost single-handedly assembled the Ambrose Center in early 2001.

He is convinced that collections like those found at Ambrose and Coriell are of “profound interest not only to systematics,” the evolutionary traces connecting all living things, “but to a variety of disciplines in the scientific community, including conservation and industry.”

But standing there, all I felt was that these contraptions bleed the color out of life. I climbed a small step stool, balanced myself against one of the vats, and after a hydraulic release, lost my head to a puff of white decompressed gas.

When the haze finally cleared all I saw were a few metal handles protruding from a misty layer sloshing against frozen insides. I blew the gas out and saw the racks and the grid of vials all diligently labeled. Though a marvel of organization, the vats and the gas and the smiling technicians had me feeling really disappointed. I’m sure they expected me to say something like “wow,” or “that’s really cool.” But I couldn’t because there wasn’t any mystery to those specimens. The technology is impressive and oppressive at the same time.

Angelique Corthals, the Curatorial Associate in direct charge of the day-to-day operation of the facility, cares for these colorless steel giants. Sitting in her office, I was relieved to see a few encased phosphorescent butterflies hanging from the walls, and some live Central Park caterpillars munching away at fresh iceburg lettuce on her desk. She noticed me watching their methodical crunch. “One of the technicians is sectioning these boys now. Central Park is as important as the Amazon, don’t you think?” She giggled, half sad, and combed her fingers through her wild hair.

Corthals is quick to say that the goal of the Ambrose Center is not only to preserve, but also to catalog. She and DeSalle are building a library of information along the same lines of what has been built for the various genome projects. It’s almost as if she’s read my disappointment, because I do feel like I’ve been wandering among arctic stacks. The volumes in this library are not as easily stored, although they do have a database that digitizes their collections in the same way that NCBI (National Center for Biotechnology Information) stores its sequence data. The real achievement of the Ambrose Center is its capture of the primary sources.

And it is an achievement. Despite my initial revulsion, it’s clear that the only way to go about doing something like this is to do exactly what the Ambrose staff has done. Corthals and DeSalle are not going for opulence; they’re going for volume. They take what fragments they can, and pare whole organisms to their biological essence. The key is to use whatever works to get the most species into the smallest possible space.

Whether or not they shove the entire organism into a test-tube is really immaterial. Molecular biology has changed the concept of what is whole. Each cell is a reflection of the entire animal. Not morphologically, but at a fundamental molecular level, whatever is in one differentiated cell is really all you need. The rest is extravagant redundancy. The collection contains DNA and tissue snapshots of ecosystems, it’s a quick read on current ecology, an abbreviated record of what is.

So what can you use this library for? Like most people awash in the Google age, I tend forget what a regular library is for let alone one that shelves thin slices of meat. If the purpose is not to provide genetic material to recreate, what are all these frozen samples actually doing for us? DeSalle is proud of the current applications. For example, the Ambrose collection has the largest archive of sturgeon tissues in the world. These tissues are used to diagnose caviars.

Apparently, it’s hard to tell the difference between beluga and sevruga caviars from their appearance alone, but using the specimens in the collection as a reference, it’s possible to catch Russian traders packaging the less expensive sevruga as beluga. The center also routinely receives samples of bush meat from the captured stashes of African traders.

By scanning the tissue against the archive, African authorities can build a case against a trader suspected of killing endangered species like the Red Colubus. And finally, microbial communities form the living bedrock of the collection. A spoonful of water from Amazonian Brazil has a characteristic microbial footprint that distinguishes it from a spoonful of dirt scooped out of New Jersey. The microbes are captured on filters becoming signatures of that corner of earth.

This is all well and good, but the stuff that really gets DeSalle going is what the Ambrose collection means to discussions about life, its history, and its evolution. Almost any taxonomist will tell you that our understanding of the trees of life evolve only a bit faster than life itself. DeSalle concedes that models of the various turns life has made are all severely lacking.

“We get little glimpses into the organization of species and the nature of evolution every time someone identifies a new species, and that finding will undoubtedly change our perception of the living tree. It’s a constant chase to find an ultimate truth.” Still, he admits that truth finding in a field as mutable as biology is a losing battle.

“When we’re pretty confident we’ve mapped an entire branch of life, that branch is not really a truth. It’s merely the way things are in the evolutionary moment, or our understanding of an evolutionary moment past.” Some taxonomists are so frustrated with gaps in ancient information they’ve proposed a here-and-there model, a model that takes into account only the root of all living things, and all living things. There simply isn’t enough data to unequivocally fill the jump from there to here.

But bolder people in the field are trying to get their heads around whatever we do know. Researchers at the National Science Foundation are working on The Tree of Life, the goal of which is to define the relationships between all known species. A tree like that has to be malleable. It has to accommodate change.

There is no room for ego in taxonomy. “It would be nice to have a central, unchanging insight,” said DeSalle, “but we’re unlikely to have another Darwinian law in biology any time soon. You’d like to have something that has a beginning and an end, but natural history science is always revisionary.” Darwin’s blinding insight into natural selection holds within it the very reason for why there is no beginning and no end. Life cannot evolve from nothing, and evolution is built to withstand time. Tracing the path between this unseen beginning and the unforeseen end is the real challenge.

Stephen J. Gould has perhaps written the most eloquently about the relationship between theory and biological reality. “No matter how adequate our general theory of evolutionary change,” he writes, “We also yearn to document and understand the actual pathway of life's history. The actual pathway is strongly underdetermined by our general theory of life's evolution.”

DeSalle has spent his life building and rebuilding trees. He claims that being a taxonomist is a bit like chasing your own shadow. “You’re never quite there.” But with frozen tissue repositories grouping fleeting species, at least we’re somewhere. If nothing else, the Ambrose collection is a physical statement of what we understand now, a statement that can change quickly to capture what we will understand.

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