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CHAPTER 1
Pushed up a Mountain and into the Clouds: The Olinguito (Bassaricyon neblina)
Kristofer Helgen still remembers the moment he opened a drawer at the Field Museum of Natural History in Chicago, Illinois, and discovered a new species inside. It was December 2003, bright and cold outside — a northern winter. The crowded city streets had been scoured clean by winds gusting toward the city across Lake Michigan.
In the Field's extensive mammal collection, it was warm and quiet. There is something hermetic about the collection, deep within the museum's interior, insulated by thick walls — a warren of brick-bounded rooms with no windows. A few other researchers were working quietly at desks, carefully measuring a row of identical-looking brown bats or hefting a walrus skull from a cabinet as if it were a bowling ball. A researcher at the University of Adelaide Environment Institute, Helgen stood before a cabinet stretching from floor to ceiling. Several drawers supposedly contained the skulls and preserved skins of a small, arboreal raccoon-like mammal called the olingo, which lives in the remote cloud forests of Central and South America. Helgen had traveled to the Field Museum specifically to examine its olingo specimens, but when he pulled open the drawer he knew he'd found something else instead.
"There were these gorgeous soft, thick red-furred things," he tells me. "I knew instantly they weren't olingos. They're nothing like anything anyone has ever described or put a name on."
Eventually, after a decade of careful investigation, which included a field expedition to northern Ecuador to find the animal in the wild, Helgen named the new species the olinguito. In a formal description published in 2013, he gave the species the scientific name Bassaricyon neblina from neblina, Spanish for mist. He found it in the mist. He named it, and he made it real.
"It's a perfect illustration of how something can hide in plain sight when you just don't know what you're looking at," says Helgen.
If anyone in the world was qualified to discover the olinguito — undocumented in an otherwise exhaustively well-cataloged museum collection like the Field's — it was Helgen. In the past decade he has named more than thirty new mammal species and subspecies, all from archived specimens he and his collaborators have found in museum collections.
In fact, he has been preparing himself for this research for more than half of his life. "I became fascinated in my earliest childhood with the question of how many kinds of mammals there are in the world," says Helgen. "By the time I was ten years old or so I knew the scientific name of almost every mammal."
At thirty-seven, Helgen is still young, with a mop of red hair not unlike one of the olinguito pelts at the Field Museum. His ability to detect subtleties between specimens is well known. When he was still a child, Helgen says, he had already identified several taxonomic blind spots — entire genera that remained unresolved. No one knew for certain how many species they even contained. "At the top of that list," he says, "was Bassaricyon, the genus of the olingos."
The specimens: when a museum specimen is collected in the field, it is skinned and prepared. It begins the process of becoming a zoological artifact that can retain its meaning for centuries. The soft tissue is removed. The bones and skull are placed in a case filled with dermestid beetles, which efficiently strip the flesh in a matter of hours and leave behind a meticulously cleaned skeleton. In the current era of molecular biology, when a specimen is collected in the field researchers might take multiple tissue samples and freeze them for later molecular analysis of its DNA. But when the first olinguito specimens were collected in Ecuador and Colombia, no one could have foreseen the advent of molecular technology. No one even knew what DNA was — research on its structure was still decades away. Back then the specimen just became a pelt in a drawer with a skull and a disarticulated skeleton in a box beside it. Each bone has the specimen number carefully inscribed on it by hand. In their drawer, the olinguito skins look like a collection of bright red stoles laid side by side. Bird skins and mammals are stuffed with wads of white cotton in the eye sockets. Insects are mounted on pins. Fish and amphibians are either stored in liquid preservative or dried.
Sometimes there is no skin at all: only a skull has survived, or just part of the skull — a broken fragment and maybe a few bones. A beetle specimen could be missing its abdomen; a gecko might have shed its tail and left a ragged stump; the frayed wing of a bat specimen is marked by a perfectly round pellet hole — a reminder that a field collector shot it from the sky, watched it tumble through the air, and collected it where it fell. A researcher must work with whatever material is in the collection.
The Bassaricyon genus had remained a puzzle since it was first erected in 1876. Helgen decided to solve it, first methodically identifying its members, then gradually filling in what he believed were the remaining gaps in the record. In the past, he says, some species had been named and quickly forgotten, not properly incorporated into the family tree; others were what he now calls oversplit — when a single species is incorrectly divided into several species that don't actually exist. To makes sense of it, Helgen knew he would have to search museum collections worldwide, locating, comparing, and measuring as many olingo specimens as he could find.
"I learned to tell the olingos apart," he says. When he opened the drawer at the Field, expecting to find it filled with olingos, Helgen says his first thoughts were, "What am I missing? Is this the wrong place? What is this creature?"
He scrutinized the specimens, absorbing their smallest details. "I opened the skull boxes that were next to them and, sure enough, it is a procyonid, and it is very much like an olingo," he says. "But something completely different."
And even I, untrained in detecting the subtle — often almost imperceptible — morphological differences between very similar species, can appreciate that olingo and olinguito skulls are not the same.
The differences are narrow but deep. Olinguitos are smaller, weighing about two pounds, the smallest members of the raccoon family. They have smaller teeth and numerous subtle differences in their skull morphology. They live at higher elevations than the olingos, between five and nine thousand feet above sea level. Their pelts are longer and denser than those of their closest relatives — a specific adaptation to their habitat high in the elevated rainforests of the northern Andes.
"You might expect it to live on a single mountaintop," says Helgen. "Maybe that explains why everybody had missed it. But this thing is widespread in the northern Andes. And then you might expect that there's not a lot going on with variation within it, but it turns out there were four very different kinds of olinguito. We were able to name them all as subspecies."
In fact, specimens of all four of the newly named subspecies have spent decades in collections, unnoticed until now. The holotype of the nominal species — its full scientific name is Bassaricyon neblina neblina — resides at the American Museum of Natural History in New York: specimen M-66753. As with all holotypes, regardless of institution, it is now clearly marked with a red tag to denote its primacy as a type specimen, and securely locked away. A holotype is irreplaceable and is subject to the highest security. The specimen was collected at Las Maquinas in northern Ecuador on September 21, 1923, by George Henry Hamilton Tate, an American field biologist. It spent ninety years stored in the collection. The first olinguito was collected even earlier, in June 1898. That specimen is part of the American Museum of Natural History's mammal collection too. Examples of the three other olinguito subspecies are part of the mammal collection at the Field Museum — all collected in Colombia in the 1950s. Suddenly the entire Bassaricyon genus had to be revised to incorporate its newest members.
There is a photograph in Helgen's description of the olinguito, taken on September 6, 1951 — a black-and-white image with a strange greenish tint. In it an Ecuadorian hunter, bearded and barefoot, wearing patched jeans, squats on the grass near the edge of the jungle in San Agustín, Colombia. He squints up into the camera. In each hand he holds a dead olinguito. Tied to a string across his chest is a long-tailed weasel (Mustela frenata). The photo was taken by Philip Hershkovitz, a prolific curator and specimen collector who spent fifty years at the Field Museum until his death in 1997. The body of each olinguito is about the size of a house cat, ending in a straight brushlike tail that is longer than the rest of its slender, sinuous body. One of the animals the hunter holds became — sixty-two years later — the holotype for another subspecies, named Bassaricyon neblina hershkovitzi. In other words, the photograph captures the exact moment a new species was discovered. It also marks the moment the discovery was overlooked — the precise moment it slipped away.
It had been overlooked before, and it would be again. In the 1960s and 1970s, says Helgen, an olinguito was part of several zoo collections. It made different vocalizations than other Bassaricyon. It refused to breed with its olingo cagemates, so it was moved endlessly from zoo to zoo — from St. Louis to Washington, and on.
But it was a misidentified olinguito.
The four olinguito subspecies are distinct morphologically — Helgen's hundreds of precise museum measurements prove that. But they live in different places, too. Eventually it became clear that the olinguitos each occupy their own subtle ranges and territories. One lives in the forest canopy in northern Colombia, on the western slopes of the Western Andes; another is found to the south and east, across the desolate high-altitude passes of the Western and Central Andes mountain ranges, on the eastern slopes of the Central Andes; the third subspecies lives southward, in the mountainous parts of northern Ecuador. Finally, another more mysterious subspecies seems to inhabit the gaps left by the other subspecies, living in the porous, poorly defined spaces between them.
Helgen formulated their distinct territories by plotting the collection data of each museum specimen on a map. "I drilled down and made sure I understood the complex northern Andean geography," he says. "I looked it up in maps and gazetteers and things. The situation crystallized, and I realized these different slopes and different sections of the Andes were correlated with these different morphologies."
In August 2006 Helgen assembled a small team of zoologists and traveled to Ecuador to try to find the olinguito in the wild. Roland Kays, director of the biodiversity laboratory at the North Carolina Museum of Natural Sciences, accompanied Helgen to the Otonga Nature Reserve on the western slopes of the Andes in northern Ecuador. "They're very steep mountains, and they're covered in this cloud forest," says Kays. "The higher up you get, the more dwarfed the trees get, but there's still some fairly big trees. It's like the tropical rainforest, but pushed up a mountain and into the clouds."
A few years before, he says, during fieldwork for his graduate studies, he'd published some early data on the olingos. In the process, he had become the de facto world expert on the Bassaricyon genus. Until then no one had studied them closely at all. For three weeks in 2006, on steep slopes covered with fig trees, Kays and Helgen conducted an extensive mammal survey. They erected mist nets for bats and set traps in the understory for ground-dwelling mammals. And they both craned their necks at night peering into the dimness, shining flashlights into the mist-choked canopy to search for olinguitos.
"There's all sorts of crazy, diverse species," Kays says. "It's hyperdiverse. You get different highland versions of what's in the lowlands. That's what the olinguito is, basically: it's a mountain-specialized form, because it's so cold up there. It's not freezing cold — it's not ice cold — but it's not the tropical weather you think of for the rainforest, and it's very damp."
The damp Ecuadorian fig tree forest: a strangely canted world, everything growing skyward from the green slopes, as if from the deck of a sinking ship. Helgen sighted the olinguito in the trees almost the moment he arrived. "We found it on the first night we went down to look for it," he says.
There are all sorts of reasons it has managed to stay hidden for so long among the clouds, in the tangled fig trees of Otonga Reserve. "It only comes out at night," he says. "It doesn't really come out of the trees. It's pretty shy, and it looks to the untrained eye either like an olingo or like a kinkajou — and those two other types of animals live in the same geography."
Like the olingo and the kinkajou, the olinguito has adapted perfectly to its environment — a life spent in the canopy of the cloud forest. "It has a long tail," says Kays. "It's a very good tree climber. It has very good balance, and it's still light enough that it can jump from branch to branch. And it has these big eyes because it's doing this high-wire act at night when there's absolutely no light. Imagine not just walking around the forest floor at night but jumping from tree to tree."
Occasionally taxonomists discover what they call a cryptic species: a species that is genetically distinct but so similar morphologically to an existing species that the two are indistinguishable. With the advent of DNA sequencing technology to detect subtle genomic differences, the discovery of cryptic species has become much more frequent. In September 2016 researchers at Goethe University in Frankfurt, Germany, announced that the giraffe — one of the most morphologically distinct species in the world — is actually a wide-ranging group of four different species. They don't interbreed at all. In fact, the four species are as genetically distinct as the polar bear (Ursus maritimus) is from the brown bear (Ursus arctos). But the olinguito is not a cryptic species. The moment Helgen opened the drawer at the Field Museum, he knew he'd discovered a new species. It diverged from its closest relatives an estimated 3.5 million years ago, evolving its own distinctive characteristics. Helgen's discovery made headlines across the world. The olinguito was the first new species of carnivorous mammal named in the Americas for thirty-five years.
"What is it when we add one more species?" Helgen asks. "For mammals, there are only about six thousand of them. There are a huge number of entities and agencies and people on this planet who take great interest in knowing something about each of those six thousand mammal species. Every time I name one of these species it enters the pipeline and people start to think more about it — try to learn more about it. It gets on endangered species lists at the national and provincial level."
Helgen and Kays estimate that about half of the olinguito's range has already been deforested — urbanized, denuded, or converted to farmland. "These ecosystems that are out there," says Helgen, "we understand them extremely poorly. They're unbelievably complex, much more so than anything man-made. To really get how they work, we need more than the embarrassing misunderstanding of not even seeing the olinguito that's already there — right in front of us."
(Continues…)
Excerpted from "The Lost Species"
by .
Copyright © 2017 Christopher Kemp.
Excerpted by permission of The University of Chicago Press.
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