Abstract:
Since
their formal description by western scientists over a century ago,
the dramatic tepuis of the Guiana Highlands (GH) have been a source
of fascination and continuing scientific research starting with
Roraima Tepui and proceeding to Auyan Tepui in the 1930s. After
nearly a 80 years of exploration and surveying, the scholarly
concensus is that larger mammals are absent from the tepui summits.
However, consistent reports of larger anaimals sighted on the tepui
summits (almost exclusively lowland organisms), continues. The 2008
photographing and sighting of the Southern Tamandua Tamandua
tetradactyla on the summit of Auyan Tepui represents an
interesting case of medium sized exclusively insectivorous mammal
living on the summit of a tepui. Diagnosed as Tamandua
tetradactyla nigra, this animal is mentioned to inhabit the
summits of Auyan Tepui by Tate in the late 1930s. Other forms of the
order Pilosa mentioned to inhabit the tepuis are the giant anteater
Myrmecophaga tridactyla and the pale throated sloth Bradypus
tridactylus. The presence of these animals on the tepui summits
raises questions about tepui carrying capacity, gaps in our knowledge
about tepui ecology and fauna, and how these ecosystems will change
with future anthropogenic climate change. To address these questions,
I recommend a meta-analysis of scientific documentation concerning
tepui ecology and ecosystems to determine what animals on the tepui
summits would be considered anomalous and what animals are already
known to invade the summits. Once this is completed, a system for the
future monitoring of the tepui summits using expeditionary surveying,
GIS analysis and camera trapping will help determine the dynamics of
tepui summit ecosystems and biota.
Introduction
The
exploration of the tepuis in the Guiana Highlands has yielded a
plethora of information regarding the distribution and endemicity of
unique tepui summit life, but has produced some contradictory results
regarding the distribution of large vertebrates. The first list of
the mammals of the Guiana Highlands was compiled by G.H.H Tate in
1939, based on three expeditions: the 1927-28 Day expedition to
Roraima, the 1928-29 Tyler expedition to Duida, and the 1937-38
Phelps expedition to Auyan Tepui. The recent history of the
exploration of Auyan Tepui has been characterized by periodic
expeditions, long gaps in surveying, and a few target oriented
searches by local explorers.
Auyan
Tepui was explored by Terramar S.C during the mid 1980s, and in 1994
by the AMNH and
Terramar.
There was a significant increase in the exploration of the tepuis in
the 1980s and early 1990s by the American Museum of Natural History
(AMNH); five separate expeditions in total which surveyed and
explored a variety of different tepuis summits, however the field
work tapered off due to a lack of funding, public disinterest, and
bureaucratic complications. Auyan Tepui has not been explored
entirely, with the possible exception of the work of Alexander Laime,
who lived on Auyan Tepui for a considerable amount of time, and had
the opportunity to extensively observe its wildlife in great detail.
Unfortunately, Laimes' observations have never been systematically
recorded, and are subsequently mostly lost. There have been
sightings by Terramar expedition members of larger vertebrates on the
tepui summits (such as Tapirus
terrestris and
Panthera onca),
but no confirmed reports, and no long term studies have been
undertaken so far to confirm or refute these sightings.1
The consensus is that the tepui summit lack the diversity of
ecosystems and resources to sustain medium sized mammals. Thus, the
limited number of mammals sighted during periodic expeditions have
been considered anomalous.
While
the tepuis were initially considered to be “lost worlds” where
archaic lazarus taxon reside, research and exploration in the 1970s
challenged this assumption. Recent molecular and paleoecological
studies have further challenged the long term isolation of the tepui
summits, demonstrating that their vegetational assemblages are the
result of post Pleistocene warming, and that their herpetological
make up is mostly composed of recent species immigrations, as opposed
to vicariant evolution based on the fragmentation of paleofaunal
populations.2
Despite
our current knowledge of the floristic make up of the tepuis and
partial phylogeny of its herpetofauna, there has been a lack of
studies on the carrying capacity of the tepui summit ecosystems. This
gap in our knowledge regarding the potential for tepui ecosystems has
limited our understanding of the possible pathways for lowland
colonization of the tepui summits, and what organisms in the future
may be expected to invade the summits during periods of climate
change.
Tepui
Summit Mammals
This
characterization of the tepui summits as being devoid of larger
mammals is consistent with the work of authors such as Perez-Zapata,
Pokorney, and Havelkova. The lack of larger mammals is due to
difficulty in accessing the topographically isolated tepuis, as well
as the limited sources of food and suitable surface area on the tepui
summits. As an example, in Havelkova
et al the authors
state “Mammals on the tepuis are scarce and probably represent
stray animals (e.g. Panthera
onca in Auyan Tepui)
or extremely rare endemic taxa (e.g. Podoxymys
roraimae).”3
Despite this characterization, coatis can added to the list of
mammals known to inhabit the tepui summits based on the work of
Havelkova et al in 2006, supported in Robovsky et al 2007, Barkoczy
2009, and detailed in my blog entitled Brown-nosed Coati on
Auyan-Tepuy, parts 1 & 2.4
With the addition of coatis to the summit fauna of certain tepuis,
one would expect that other medium sized mammals may also inhabit or
regularly invade the tepui summits. This appears now to be the case.
In
2008, a Southern Anteater (Tamandua tetradactyla nigra) was
sighted and photographed on the summit of Auyan Tepui, adding yet
another species of medium sized lowland mammal to the short list of
vertebrates known to at least invade the tepuis. This is possibly the
first time a Tamandua has been photographed on a tepui summit, and
its presence here is interesting for a variety of reasons. First and
foremost, its presence confirms the statements by Tate during the
initial explorations of the summit of Auyan Tepui regarding the
summit fauna. Secondly, its presence on the Auyan Tepui indicates
that Auyan Tepui and possibly its sister tepui the Chimanta Massif
may have a greater ecological carrying capacity than previously
thought. Third, it indicates that lowland animals have seemingly
little problem invading tepui summits to forage when there is
sufficient enticement to do so.
Description
Location
of the sighting. January 5th 2008, on top of the
second wall near the monument of Jimmy Angels landing in 1937.
Altitude is 1841 meters. Approximate time 20.00 GMT. Located in a
plain composed of extremely moist soils and bogs, among herbaceous
vegetation. Exact coordinates are N5 56.182 W62 35.985
Figure
1. Map of Auyan Tepui, where the yellow pin mark indicates the
location of the Tamandua sighted.
Behavior:
Engaged in foraging among herbaceous plants, the tamandua immediately
adopted a defensive position with its arms extended and claws pointed
outward. The animal resumed foraging when the human photographers
walked away from it.
Observers:
Alberto Pomares and the 2008 expedition crew observed and
photographed the animal. The presence of a tamandua on the summit of
Auyan Tepui was not considered unusual as “there are many ant
colonies on Auyan Tepuy, his main or only food”.5
Physical
description: Adult tamandua, sex undetermined. Snout is black
color, which extends and terminates at the animals eyes. Pleage color
is two toned, light cream colored pelage with a light v shaped black
marking on the dorsum and ventral side of the animal. Neck is a
darker coloration of light orange. Pelage coloration is consistent
with Tates description of “Auyan-Tepui” tamanduas. Photographs of
the ventral and dorsal side of the tamandua are below in figure 2
Fig
2. Tamandua photographed in 2008. Top image facing the tamandua, bottom image is a photograph of the dorsal view of the animal.
Photographs courtesy of Alberto Pomares can be found on the Alberto Pomares website.
Diagnosis
The
tamandua photographed is the southern tamandua species Tamandua
tetradactyla nigra,
based on the geographic location of the tamandua species.6
Tamanduas are common in diverse habitats across South America, and
exist at variety of elevations. They exist in Venezuela primarily in
thorn forests, in dry areas, and spend most of their day in trees.
Their home range in Venezuela is 375 ha with an average daily
movement of 3000 meters.7
However, their average range can vary with location; in Brazil the
range of multiple animals has been recorded at 100 ha.8
Their diet is primarily social insects; with an approximate ratio of
50% ants and 50% termites.9
Tate notes the presence of tamanduas on the summit of three tepuis;
Roraima, Auyan Tepui and Duida Tepui. He states that the pelage of
the tamanduas in the Guiana Highlands and the tepui summits is
unstripped and straw colored.10
Regarding Tamandua
tetradactyla, Tate
states:
“ the
occurrence of that pallid form, though in a general way regional,
seems unrelated to the conditions of climate or forestation. It is
equally prevalent among the dwarfed woods of the Auyan-Tepui plateau,
in the arid cactus belt at the Rio Tocuyo, and in the heavy rain
forests of eastern Ecuador.”11
Tamanduas
give birth to a single offspring after a gestation of 4-5 months,
with a mean of 160 days. Juvenile tamanduas ride on their mothers
back for up to a year learning how to forage. The general behavior of
tamanduas is that of solitary nocturnal or diurnal behavior. Their
range in the Patanal of Brazil is estimated at 350 to 400 ha, with a
population density of .20 to .34 individuals per kilometer.12
The
giant anteater Myrmecophaga
tridactyla has also
been noted on Auyan Tepui.14
According to Tate the material for Myrmecophaga
on Auyan tepui includes 1 animal and on “pick-up skull”.15Tate
states:
“A
full-grown giant anteater was seen at “Tree Savannas” foot of Mt.
Duida, but not captured. These animals apparently range all over the
Guianan savanna region up to 5000 feet. They are met with in forests,
though usually near savannas. Thomas records a specimen from 'Mount
Roraima, 5000 feet”.
Giant
anteaters are mostly present in grasslands where they feed on social
insects such as termites and ants. Generally solitary in behavior,
giant anteaters socialize during courtship, aggressive encounters,
and in the case of females caring for their offspring. Their general
population density varies. Some authors suggest a home range between
9 and 25 kilometers, while other authors suggest that they are
nomadic.16
The
pale-throated three toed sloth, Bradypus
tridactylus, is listed
as being present on the tepui summits. 17
Although this reference gives no indication as to the specific tepui
on which B.
tridactylus
has been sighted, its presence on the tepuis is in the established
literature regarding its distribution and conservation. Its
distribution is within the areas of the Guianan shield and highlands
that include the tepuis of Venezuela ie. the neotropics of Venezuela,
Guayana, Suriname and French Guiana.18
It is entirely arboreal and primarily inactive, sleeping the majority
of the day. Its diet is based upon the leaves of trees.
Discussion
The
presence of tamanduas on the summit of Auyan Tepui represents
something a quandary in terms of the academic knowledge of tepui
summit fauna. First and foremost, the presence of this animal was not
surprising to the expedition members who photographed it. They were
pleased that this animal was present to pose for the camera and show
its defensive posture; the display resulted in excellent photographs.
In this respect, the presence of such an animal was expected to some
degree. This is not entirely surprising; Tate records the Phelps
expedition encountering tamanduas on the summit of Auyan Tepui,
although they have for some reason been omitted from more recent
surveys.
With
regard to the presence of giant anteaters on Auyan Tepui, at this
point the only reference to these animals comes from Tates “Mammals
of the Guiana region”. Compounding this lack of information is the
ambiguity of his entry, which gives no indication as to the location
or altitude on Auyan Tepui at which either the individual or the
skull was located. It is interesting to note that while giant
anteaters are found across the llanos, their ability to climb
structures has been recently noted. Young, Coelho and Wieloch
reviewed the climbing ability of the giant anteater Myrmecophaga
tridactyla in their
2003 article, and conclude that tridactyla
is in fact fully capable of scaling not only termite mounds in search
of food, but also trees upwards of 5 meters in height and artificial
enclosure barriers 2 meters in height.19
This ability of giant anteaters to climb obstacles demonstrates their
ability to theoretically access the summit of the Venezuelan tepuis
given the proper incentive, lending credence to Tates work.
Interestingly
a partial analogue to the summit of Auyan Tepui can be found in the
Serra Canastra National Park in Brazil, which has a comparable area
of the summit of Auyan Tepui ( approx 715 square km and 700 square
km, respectively). While obviously phytologically different, both
locals are semi isolated and higher in altitude than the surrounding
lowlands ( average elevation of Serra de Canastra is 1400 m), and
maintain patches of brush lands and gallery forests. Results from a
survey of of Serra Canastra carried out between November 1979 and
June 1980 indicated a population density of 1.3 animals per square
kilometer, much higher than that recorded elsewhere in South America.
The existence of such an analogue, with a high density of
Myrmecophaga tridactyla present, indicates that giant
anteaters might indeed be present on some of the larger more
accessible tepui summits.
The
only thing which restricts animals such as tamanduas and giant
anteaters from the summits of the tepuis is the topography and
intrinsic carrying capacity of a given tepui. Certainly, tepuis with
small summit areas harbor fewer available resources than the larger
ones. In the case of Auyan,the largest tepui interms of continuous
summit area, the carring capacity may be unusually high. In this
case, it may be useful to diagnose the summit biota of Auyan tepui
less in terms of its similarity to other tepuis, and more in terms of
its unique characteristics.
Ants
of Auyan Tepui
A
critical limiting factor for the distribution of both Tamandua
tetradactyla and
Myrmecophaga tridactyla
is the availability of social insects which are their principle food
source. Ants and other social insects have been surveyed to some
extent the tepui summits. Jaffe, Lattke, and Perez Hernandes produced
a survey of the various ants of the tepui summits in which they
compare the distribution of tepui summit ants, their lowland
counterparts, and the apparent richness of ant diversity on the tepui
summits.20
They found that ants are most abundant at an altitude of 800 meters;
altitudinal diversity decline was attributed to the difficulty in
colonizing the tepui summit ecosystems. This is a trend with the
tepui summits, and extends to insects as well as higher animals. For
our purposes, the analysis of Auyan Tepui is particularly
interesting. According to their findings, Auyan tepui contained the
highest divesity of ant species, (14) second only to the Chimanta
massif (10 species). The stated reasons for this high diversity is
the comparatively “Moderately harsh climate conditions (less
altitude)” of Auyan and Chimanta. This hints at the fact that Auyan
Tepui may have the highest ecological carrying capacity of any of the
tepuis, due to its climate, size, and the availability of
micro-habitats and the diversity of ecosystems it contains. The
authors characterized:
“a
direct relationship between area and diversity is confluent with is
land biogeography theories...although in the case of tepuies, part of
the fauna is derived from the surrounding lowland forests rather than
some distant mountain source. The larger summits offer a greater
diversity of habitats and this should translate into more
opportunities for colonization”.21
Indeed
this seems to be the case; Auyan Tepui and the Chimanta Massif share
he greatest diversity of ant species at 14 and 10 respectively. The
next highest diversity of ants are found on Huachamakari Tepui and
Aparaman Tepui at 5 species. The majority of tepuis sampled harbor no
more than 1 to 2 species. Auyan Tepuy is a statistical outlier in the
distribution of tepui ant populations, lying outside of two standard
deviations from the sampled tepui ant populations. Jaffe, Lattke and
Perez-Hernandez conclude that 1) ant distribution on the tepuis can
be explained if the tepuis are treated as biogeographical islands ie
climate, altitude and niche abundance (expressed partialy as surface
area) limit the colonization of ant species 2) the distribution of
the species of ants suggest different colonization methods, which do
not conform to a single theory but rather represent a complex history
of colonization following island biogepgraphy and panbiogeography.
The work of the authors suggests a complex history of climate related
alterations and changes in the summit biota, expressed by Rull in his
analysis of the effects of climate change on the tepui summits. The
authors tentatively date the vicarriant speciation of the ant genus
Selenopsis
at 8000 kya, based on a change in climate from an arid ecology to a
more humid one at the start of the Holocene. It would be interesting
to see if the various ant species on the tepui summits are old enough
to have existed in their present locations during the theoretical
tepui paramo period suggested by Rull as being the dominant tepui
summit Pleistocene vegetational assemblage.22
The
Meaning of tamanduas and members of the order Pilosa on the tepui
summits
The
presence of Tamandua
tetradactyla on the
summit of Auyan Tepui may be surprising given a broad
characterization of tepui summit fauna, but is certainly not unusual
to indigenous scientists and has been noted since the initial
explorations of Auyan Tepui. The presence of giant anteaters on the
summit of Auyan Tepui has only to my knowledge been noted by Tate,
and supporting evidence for Myrmecophaga
tridactyla on the
tepui summits after
Tates publication has not been noted to my knowledge. It is known
that both the giant anteater and the southern tamandua share
habitats, they occur in the same range, and the two groups appear to
coexist well in the same ecosystem.23
Thus, evidence for one does not preclude the presence of the other,
due to competition for resources. The presence of Bradypus
tridactylus in a tepui
environment is unusual, given the distribution of B.
tridactylus
and composition of tepui summit flora, not to mention the difficulty
in accessing the summit of a tepui. Due to the behavior of this
animal, being almost entirely sedentary, and dependent on extensive
canopy cover for both food and protection, I am inclined to dismiss
the notion of Bradypus
tridactylus on any
tepui summit. The limited presence of gallery forests and the
preponderance of herbaceous assemblages, combined with the
impoverished soils of the tepui summits which limit the growth of
extensive gallery forests should render the tepui summits off limits
to this sloth species.
Conclusion
The
presence of three members of the order Pilosa on the tepuis raises
questions about the distribution of mammals on the tepui summits,
tepui carrying capacity, and the scientific knowledge produced by
tepui research. In terms of mammalian distribution, it indicates that
medium sized mammals are indeed present on tepui summits; exactly
what species are present, their range, population density, and how
they fit into tepui ecology is unknown. From a stand point of
carrying capacity, the presence of at least Tamandua tetradactyla
on Auyan Tepui indicates that larger tepuis will have a
correspondingly larger ecological diversity, and may be host to more
species of mammals than previously thought.
When
it comes to our scientific knowledge of the summit fauna of the
tepuis, the presence of members of Pilosa on the summit can be viewed
from a few different angles. If we base our knowledge of tepui summit
mammals on the work of Tate and the knowledge of local Venezuelan
scientists and explorers, then the existence of Tamandua
tretradactyla (and to
a lesser extent possibly Myrmecophaga
tridactyla) on the
tepui summits is within the norm of their geographic distribution.
If, on the other hand, we base our knowledge of tepui summit mammals
on current literature regarding the tepui summit fauna, then the
presence of these animals would be considered anomalous. With regard
to Bradypus tridactylus
as a tepui summit mammal, there is no record of its presence
mentioned by Tate, and as of this writing the source material which
places this sloth on the tepui summits is not available. Given the
ecological niche of Bradypus
tridactylus, it is
very unlikely that this animal is present on any tepui summit at all.
I would consider that the sloth B.
tridactylus is
possibly not present on the tepui summits until sufficient data is
obtained to indicate that it is. In this case, sufficient data would
be diagnostic evidence of its presence (photographic or physical), or
reliable visual observations of B.
tridactylus on a tepui
summit with the specific tepui name recorded as well the GPS
coordinates of the sighting.24
This evidence needs to be produced to avoid errors in the recording
of tepui species and which could complicate future conservation
efforts.
The
presence of at least one member of Pilosa (Tamandua tertradactyla)
on the summit of Auyan Tepui indicates that Tate's observations are
correct, and by implication we may expect to see other members of
this order present as well. When these observations are compared to
the presence of coatis on the tepui summits (documented in my
previous blog) the image that emerges is that certain tepui summits
are host to a greater diversity of larger vertebrates than currently
thought. This situation has been documented in the form of
observational data by Michelangeli and the Terramar organization
during their expeditions during the 1980s. This confusion over the
status of lowland vertebrates on the tepui summits needs to resolved.
Future
Research
The
best way to solve the gaps in our scientific knowledge of the tepui
summits is to attempt to fill them. An obvious course of action would
be an extensive series of expeditions to survey and monitor the tepui
summits over time, using the latest technologies available in
geospatial science and wildlife biology (such as extensive camera trapping). This grand endeavor would
be very expensive, and is not feasible outside of large non-profit
groups (such as Conservation International and the Nature
Conservancy) or the Venezuelan government and Venezuelan
universities.
What
is feasible right now is the dissemination of current knowledge of
the tepui ecosystems, collected in a single source to aid future
research processes. In order to compile all the existing knowledge of
the tepui ecosystems, a kind of meta-analysis must be produced which
is up to date with current theories. A meta-analysis will help
determine where “anomalous” fauna and normative fauna diverge,
exemplified in this case with the distribution of Tamandua
tretradactyla and Bradypus
tridactylus
on the tepui summits. Once a meta-analysis is produced, if it can be
combined with a review of tepui summit flora and topography, a crude
carrying capasity evaluation for individual tepui summits can be
created. This could then be used to further test predictive models
for the projected impact of climate change on the tepui summits.
Furthermore, carrying capacity analysis and meta-analysis of the
entire pan-tepui region would be very useful in justifying the need
for future expeditionary research.
11)Teouy,
Colosos de la tierra. A. Michelangeli ed, Altolithos, Caracas
Venezuela 2005, 2) George, Uwe. “Tepuys,
Venezuelas Islands in Time”, National Geographic May
1989
2
1)Salerno, P. E. et al, D. C. (2012), “Ancient tepui
summits harbor young rather than old lineages of endemic frogs”.
Evolution. doi: 10.1111/j.1558-5646.2012.01666.x,
2)Garvish et al, “Ancient vicariance or recent long
distance dispersal? Inferences about phylogeny and South
American-African disjunctions in Rapateaceae and Bromeliaceae based
on ndhF sequence data” International Journal of Plant Science.
2004
3Havelkova,
Pavla et al, “Brown-nosed coati (Nasua nasua vittata) on
the Roraima tepui (Carnivora: Procyonidae)” Lynx 37, 2006.
4Havelkova,
Pavla et al, “Brown-nosed coati (Nasua nasua vittata) on
the Roraima tepui (Carnivora: Procyonidae)” Lynx 37, 2006.
Robovsky et al, “Additional report of the Brown nosed Coati (Nasua
nasua vittata) on the tepuis- The Chimanta Massif, Churi Tepui,
Venezuela” Lynx (Praha) 38, 115-117 2007, Barkoczy, Laszlo
“Globalizing a Lost world: Beauty or Benefit, what drives
conservation? The International Relations Journal, San
Francisco State University, Vol 28, 2009.
http://biokryptos.blogspot.com/2011_10_01_archive.html
5Personal
communication with Alberto Pomares regarding the presence of
tamanduas on the summit of Auyan Tepui.
6V.
Hayssen “Tamandua tetradactyla (Pilosa: Myrmecophagidae)”
Mammalian Species 43 (875): 64-74, May 2011.
7Montgomery,
G. G.. “Movements, foraging and food habits of the four extant
species of Neotropical vermilinguas (Mammalia: Myrmecophagidae)”.
Pp. 365–377 in The evolution and ecology of armadillos, sloths,
and vermilinguas (G. G. Montgomery, ed.). Smithsonian
Institution Press, Washington, D.C. 1985
8F.H
Rodrigues et al “Anteater behavior and ecology” Pp. 257–268
in The biology of the Xenarthra (S. F. Vizcaıno and W. J.
Loughry, eds.). University Press of Florida, Gainesville 2008
9Wetzel
R. M. 1985. “The identification and distribution of recent
Xenarthra ( Edentata)”. Pp. 5–21 in The evolution and
ecology of armadillos, sloths, and vermilinguas (G. G.
Montgomery, ed.). Smithsonian Institution Press, Washington, D.C.
10Tate,
“Mammals of the Guiana Region,” The bulletin of the American
Museum of Natural History, October, 1939.
11Tate,
“Mammals of the Guiana Region”, The bulletin of the American
Museum of Natural History, page 171
121)
Panera A Los Mamíferos de la
Argentina y la Región Austral de Sudamérica - Editorial
El Ateneo,
Buenos Aires.
2002 2) Desbiez ALJ, Medri Im “Density
and Habitat Use by Giant Anteaters (Myrmecophaga tridactyla) and
Southern
Tamanduas (Tamandua tetradactyla) in the Pantanal Wetland, Brazil”
- Edentata 11: p4-10.
2010
13Pilosa
is an order of mammals which includes South American anteaters as
well as extant and extinct sloths. The origin of the order is
unclear, but it seems to date from the early tertiary in South
America.
14
At the time of this writing, it is unclear to me of Tate means that
Myrmecophaga was sighted on the summit or near the summit on
the slopes of Auyan Tepui
15Tate,
Mammals of the Guiana Region, The bulkletin of the american museum
of natural history, october, 1939. page 171
16Pinto
da Silvera, “Historia natural do tamanduad-banderia, Myrmecophaga
tridactyla. Myrmecophagidae” Velozia No 7, Rio de Janerio
1969, Montgomery and Lubin “Prey influences on movements of
neotropical anteaters. In Proceedings of the 1975 predator
symposium, pgs 103-131. Montana forest and Conservation
Experiment station, Montana USA.
171)“Bradypus
tridactylus,” Edentata 11(2) 2010. page #122 2) IUCN
Red list “Bradypus tridactylu,” Chiarello,
A. and Moraes-Barros, N. accessors.
http://www.iucnredlist.org
18
Hayssen, V. “Bradypus tridactylus (Pilosa: Bradypodidae)”
Mammalian Species, 839 2009
19Young
et al “A note on the climbing abilities of giant anteaters,
Myrmecophaga tridactyla (Xenarthra, Myrmecophagidae)” Bulletin
of the Museum Biological Mello Letao, 15, June 2003
20
Jaffe, Klaus et al “Ants on the tepuis of the Guiana
Shield, a zoogeographic study” Ecotropicos, vol 6 # 1 1993
21
Jaffe, Klaus et al “Ants on the tepuis of the Guiana
Shield, a zoogeographic study” Ecotropicos, vol 6 # 1 1993
22
Rull, V., “The Guayana Highlands: A Promised (but Threatened) Land
for Ecological and Evolutionary Science”. Biotropica,
39: 31–34. 2007
23Arnaud
L et al “Density and Habitat Use by Giant Anteaters
(Myrmecophaga tridactyla) and Southern Tamanduas (Tamandua
tetradactyla) in the Pantanal Wetland, Brazil” Edentata no
11, 2010
24
This requirement is based on the evidentiary standards described in
McKlevin et al “Using anecdotal occurrence data for rare or
elusive species:the illusion of reality and a call for evidentiary
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