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CORRECTION:The IUCN/SSC Tapir Specialist Group has not declared the Kabomani tapir a “unit of conservation importance” as originally reported in this article. Nor will the proposed species be receiving an IUCN Red List categorization at this time. Instead the task force that looked at the evidence declared the species could be an Evolutionary Significant Unit, but the evidence at this time was “limited.” . |
Last year’s declaration of a new tapir in the Amazon has come under contention
The proposed new tapir species: Tapirus kabomani. Photo courtesy of: Cozzuol et al.
Nearly a year ago, scientists announced an incredible discovery: a new tapir species from the western Amazon in Brazil and Colombia. The announcement was remarkable for a number of reasons: this was the biggest new land mammal discovered in more than 20 years and was only the fifth tapir known to the world. The tapir, dubbed the Kabomani tapir (Tapirus kabomani), was described as being significantly smaller than the world’s other tapirs—but still one of the biggest land animals in South America—and with a distinctly-shaped head and darker coat. But within months other researchers expressed doubt over the veracity of the new species. The debate soon exploded into a set of dueling papers, with one arguing the Kabomani tapir is a separate species and the other asserting it may simply be a juvenile Brazilian tapir (Tapirus terrestris), its closest relative.
“[Indigenous people] traditionally reported seeing what they called ‘a different kind of anta [tapir in Portuguese].’ However, the scientific community has never paid much attention to the fact, stating that it was always the same Tapirus terrestris,” Mario Cozzuol, the paleontologist who first started investigating the new species ten years ago, said last year.
Local people have long distinguished the proposed new tapir from the well-known Brazilian tapir. According to Cozzuol and his team, this little tapir has been hunted by locals for hundreds of years. The proposed tapir was even shot by Theodore Roosevelt in an expedition in 1912, who wrote that locals described it as a “distinct kind.” Yet, for scientists to consider it a new species more evidence is needed.
In fact, disagreement over the Kabomani tapir’s taxonomy falls along three lines of evidence: genetic, morphological (i.e. physical), and local knowledge.
Painting of the new tapir species. Painting courtesy of Fabrício R. Santos.
“In our opinion, the description of Tapirus kabomani…fails to provide compelling evidence for a new species of Amazonian tapir,” write scientists in a paper this year that argues against new species status. The paper, entitled “Extraordinary claims require extraordinary evidence,” was headed up by Robert Voss with the American Museum of Natural History, the same institution that today houses Roosevelt’s specimen from 1912.
While the debate is about a single species—albeit a high-profile, so-called charismatic megafauna—it also sheds a light on how scientists work out disagreements: via papers, interpretations of old evidence, gathering new data, and eventually—hopefully—consensus. The same process has led to the acceptance of evolution, the warming of the planet due to greenhouse gas emissions, and that the Earth revolves around the sun. And now it’s being applied to the Kabomani tapir.
Tapir genetics
In the original paper describing the Kabomani tapir, Cozzuol and his team compared the mitochondrial DNA of Kabomani specimens with other tapirs. According to this genetic evidence, the Kabomani tapir split from the Brazilian tapir around 300,000 years ago. In addition, the DNA used also showed that the mountain tapir (Tapirus pinchaque) was actually more closely related to the Brazilian tapir than the Kabomani. But Voss and his team viewed the data very differently.
“Well, first, the genetic evidence for a new species is essentially nonexistent,” Voss told mongabay.com, adding that “genetic variation exists in all widespread species. The single gene that the authors sequenced routinely contains substantial sequence variation within and among populations. It’s just not unusual for one species to exhibit the variation that the authors found among their samples of Amazonian tapirs.”
Brazilian tapir in Yasuni National Park, Ecuador. Photo by: Jeremy Hance.
Brazilian tapirs have a massive range, spreading across the entire Amazon and including other ecosystems to the south like the Pantanal and the north like the Guiana Shield. Making matters even more difficult is that tapirs have low genetic divergence between groups—in other words, they evolve very slowly compared with other species. Still, Fabrício Santos, a co-author on the original paper describing the species and a response paper to the skeptics, says the genetic evidence is strong enough.
He told mongabay.com that the genetics show that the Kaomani tapir has “DNA lineages separated from all other known species.” In addition, the DNA proves that the Kabomani tapir was more divergent from the Brazilian tapir than the mountain tapir, “a species,” he noted, that was “recognized more then a century ago.” The group also ran their genetic data on the Kabomani tapir again and reaffirmed that they believed the species distinct.
However, Voss said that there was another issue with the DNA data: “we don’t actually know that the DNA they analyzed came from small, dark tapirs.” In other, words the samples came from animals killed by local hunters in the wild, so there is no physical body of the animal or so-called “vouchers,” for other scientists to examine.
But, the Cozzuol’s team countered that such circumstances aren’t unprecedented: new species of toothed whales were described recently without a physical specimen in a museum.
Morphology
The dispute doesn’t end over genetics, but goes on to the physical nature of the Kabomani tapir, or its morphology. The tapir is described as smaller—110 kilograms (240 pounds) versus 320 kilograms (710 pounds)—than the Brazilian tapir. It also has a darker coat and a distinct skull shape.
The proposed species is said to have dark fur. Photo courtesy of Fabrício R. Santos.
But Voss said that “the analyses of skull measurement data did not take age variation into account.” Voss and his co-authors believe that Kabomani tapirs may simply be juvenile Brazilian tapirs.
“It seems likely that the size, coloration, and other features said to distinguish Tapirus ‘kabomani’ from Tapirus terrestris are some mixture of individual and age variation,” Voss told mongabay.com.
It’s not impossible that scientists have confused a juvenile for a new species; it’s certainly happened before. But Santos said there was a simple way by which they knew that the Kabomani tapir was not a juvenile Brazilian tapir: “the adults can be recognized by the eruption of the molar teeth, and most of individuals have all molars erupted.”
Yet, the Voss paper notes that some molars erupt early, even before the animals lose their primary teeth.
Indigenous knowledge
The third disagreement springs from the reliability of indigenous knowledge. The “little, black tapir,” as it’s known among the indigenous Karitiana people, has long been viewed by locals as a separate species from the bigger, Brazilian tapir, which is also found in the region.
“The indigenous hunters recognized two varieties, and they used to keep as trophies the skulls of hunted animals, which were separated by varieties that we analyzed,” said Santos, who notes that this indigenous information was important because it “matched” the results of the DNA data and the morphological description.
The Kabomani tapir is said to have a distinct head shape. Photo courtesy of Fabrício R. Santos.
In other words, the discovery of the new species was not dependent on indigenous knowledge, but indigenous knowledge was initially key to pointing out the possibility of a new species and, secondly, to backing up the gathered data.
Still, Voss told mongabay.com that indigenous people often distinguish animals very differently than do scientists.
“The evidence from local people could have other explanations (native informants are often wrong about taxonomy),” he said explaining that, “Native Amazonians routinely interpret age and individual variation in large mammals as evidence for multiple species. Many tribes, for example, claim that there are two or more species of jaguar in Amazonia, due to individual variation in coat color. Some Amazonian tribes recognize as many as seven species of tapir!”
Both side agree that indigenous knowledge can play a vital role in taxonomy, but both also agree that such knowledge must be backed up by good data. Yet the emphasis here is different. Cozzuol and Santos interpret the indigenous knowledge of this “new tapir”—knowledge that cuts across many different indigenous groups and goes back centuries—as backing up their findings. However, Voss and his team view it skeptically.
“It takes patient research, including knowledge of local languages and customs to sort out the real meaning of such discrepancies between native and zoological classifications of local plant and animal species,” Voss said.
Going forward: some agreement
There is one thing both camps agree on: the need for more research. Both said they would like to see additional studies on the proposed new species, as well as tapir taxonomy in general given the many questions raised by the original description.
After Voss and colleagues released their paper, Cozzoul and his team published an in-depth response. But Voss says the response did not put the matter to rest.
“Cozzuol and his colleagues failed to effectively address our main concerns about data quality and interpretation,” he told mongabay.com
A juvenile Brazilian tapir crossing a road in the Pantanal. Photo by: Rhett A. Butler.
So, what would settle the issue?
“Properly collected and preserved specimens would help,” said Voss. “As would information from nuclear genes and a more thoughtful analysis of indigenous language use and zoological classification.”
Santos stands behind the team’s original research, noting “we analyzed about 14 individuals, mostly represented by skulls, and statistical analyses show that all tapir species can be easily discriminated.” But he also agreed that more research is a must.
“We still need to do analyses with a larger sample from more areas of occurrence…Besides, we also need to collect many more samples from [the Brazilian tapir] and [the mountain tapir]…to compare.”
The desire to conduct more research on these species is there, but the problem is a common one in both science and conservation: money.
“[The Kabomani tapir] seems to be a rare animal, difficult to trap, scattered around a large area in the Amazon, [so] we would need to engage full-time people to do a lot of fieldwork…it means personnel, money for lots of fieldwork, to survey populations in different times of the year, to map their spatial distribution, to get samples for morphological and molecular studies, and for working in the laboratories,” explained Santos.
He estimated it would cost around $200,000 to conduct such thorough research over two years, and to do further genetic research would call for another $100,000. While this may seem like a lot of money to settle a debate that probably appears esoteric to the general public, the question of the Kabomani tapir has very real implications.
For one thing, if the Kabomani tapir is a distinct species, it is possibly highly endangered. Its habitat in the Southwestern Amazon is currently facing proposed dams, a rise in road-building, and massive deforestation. If it is a new species, it needs rapid conservation attention. On the flip-side, if it’s not a distinct species, it would probably be more beneficial to spend conservation funds—which are few and far between—on animals that need it more.
“We honestly believe that, despite scarce resources or personnel, if a remote possibility of a new species like this exists, in an environment so endangered and under hunting pressure, efforts should be made to clarify both its taxonomic and conservation status,” Cozzuol and his team write in their most recent paper. “Not considering this possibility may condemn an important part of Amazonian mammalian diversity to extinction without even knowing it properly.”
Moreover, the debate over the Kabomani tapir has led to questions over another tapir. Given the new genetic evidence, researchers are asking: what is the mountain tapir? If the Kabomani tapir isn’t a new species, but just a juvenile or distinct form of the Brazilian tapir, then where does that put the mountain tapir, which was described as a distinct species nearly 200 years ago because it looks vastly different from a Brazilian tapir and lives in a very different habitat?
Voss said that given the evidence it might be time to take another look at the mountain tapir.
“[It’s] too early to tell [if the mountain tapir should be stripped of its species status], but the evidence in hand certainly suggests that we need more data,” Voss told mongabay.com. “All of the genetic evidence right now is from a single mitochondrial gene. It’s just not enough to base good decisions on.”
A captive mountain tapir. Recent genetic evidence suggests this species is very closely related to the Brazilian tapir even though it looks very different. Photo by: David Sifry/Creative Commons 2.0.
However Cozzuol and his team disagree. They write in their response paper that “[the mountain tapir] is a well-established species that was never questioned before, and presents significant morphological differences with [the Brazilian] and all other Tapirus species. Besides its unique external morphology, the development of the skull in this species follows a comparatively primitive path, very different from that of [the Brazilian tapir].”
In the midst of these scientific disputes, the world’s premier tapir research group—the IUCN/SSC Tapir Specialist Group (TSG)—took an in-depth look at the evidence. Six experts combed through the data and, based on their recommendations, the TSG decided at this time there was not enough evidence—and too many questions—to accept the Kabomani tapir as a new species or consider an endangerment ranking for it under the IUCN. Furthermore the experts found that the evidence to consider the Kabomami tapir as a “evolutionary significant unit” was currently “limited and conflicted, but nonetheless plausible,” according to one of the moderators of the expert panel, Ahimsa Campos-Arceiz, with the University of Nottingham.
“In spite of this recommendation, the TSG encourages the scientific community to pursue additional evidence to clarify the status of the Kabomani tapir,” Campos-Arceiz told mongabay.com.
In fact, the mystery of the Kabomani tapir will also be discussed at the Sixth International Tapir Symposium, held next week in Campo Grande, Brazil. The symposium brings together tapir researchers from around the world, and it’s likely that “Kabomani” will be on the minds of many and talked about not just at formal events, but over coffee, tea, and probably a few cervejas as well.
The dwarf tapir?
A pair of Kabomani tapirs caught on camera trap. The individual on the left is a female and on the right a male. Females of the proposed species are characterized by a light patch on lower head and neck. Photo courtesy of Fabrício R. Santos.
The problem of the Kabomani tapir highlights a bigger discussion amongst biologists worldwide. How many species are there? And, really, what is a species? New species used to be described almost solely on morphology. But with genetic research, scientists are now uncovering thousands of “cryptic” species that look exactly alike—both on the inside and out—but show vast genetic differences and likely don’t breed. At the same time, some animals that look very different and don’t share the same habitat still share surprisingly similar DNA.
In an age when forests are being felled at stunning rates, oceans are acidifying, and the climate is changing, such philosophical questions take on an urgency—and an emotional depth. Extinction is no joke, and mass extinction even less so. But if we don’t know what we have, how can we even save what’s there or—more bleakly—tally what has been lost?
Is there really a dwarf, black tapir inhabiting the western edges of the Amazon? There’s no question that it’s an exciting, exhilarating thought—a lost megafauna still roaming the planet. But science cannot give into excitement; it’s a sober, meticulous activity. Things like this take time. They take effort. And they take funding. They also require debate: to tease out gaps, to clarify interpretations, to understand what we’re really seeing. Whatever way the evidence turns, it will shed light not just on tapirs across South America but also on the complexity of life on our tiny, blue planet.
Citation:
- Cozzuol, Mario A., Camila L. Clozato, Elizete C. Holanda, Flávio HG Rodrigues, Samuel Nienow, Benoit de Thoisy, Rodrigo AF Redondo, and Fabrício R. Santos. “A new species of tapir from the Amazon.” Journal of Mammalogy 94, no. 6 (2013): 1331-1345.
- Cozzuol, Mario A., Benoit de Thoisy, Hugo Fernandes-Ferreira, Flávio HG Rodrigues, and Fabrício R. Santos. “How much evidence is enough evidence for a new species?.” Journal of Mammalogy 95, no. 4 (2014): 899-905.
- Voss, Robert S., Kristofer M. Helgen, and Sharon A. Jansa. “Extraordinary claims require extraordinary evidence: a comment on Cozzuol et al.(2013).” Journal of Mammalogy 95, no. 4 (2014): 893-898.
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