Journal of Tropical Biodiversity and Biotechnology
Volume 04, Issue 03 (2019): 97 — 106
DOI: 10.22146/jtbb.45667
Research Article
Antlers Characterization for Identification of Deer Species
(Family Cervidae) in Indonesia
Donan Satria Yudha1, Muhammad Zulfiqar Meizar Pratama2*, Rury Eprilurahman1
1) Laboratory of Animal Systematics, Faculty of Biology, Universitas Gadjah Mada, Yogyakarta. Jl. Teknika Selatan Sekip Utara
Yogyakarta, 55281
2) Faculty of Biology, Universitas Gadjah Mada, Yogyakarta. Jl. Teknika Selatan Sekip Utara Yogyakarta, 55281
*Corresponding author, tel.: +62 82136900891, email address: zulfiqar285@ymail.com
Keywords:
deer
antler
characterization
identification
Indonesia
Article history:
Submitted 08/05/2019
Revised 13/09/2019
Accepted 25/09/2019
ABSTRACT
There are five species of deer (family Cervidae) living in Indonesia today. Male deer
possesses antlers, a unique character of male deer. Antlers have economic values for
quite a long time. Antler’s growth is influenced by several factors, therefore each
species of deer have its own unique antlers’ shape and size. Antler’s identification
usually relies on size measurement and overall shape of complete antlers which still
attach to the skull. It is difficult to identify shed, broken or individual antler. The
purpose of the research is to understand antlers’ morphological characters on each
species to become diagnostic characters. Specimens analysed were collections of LIPI
and were analysed with Principal Component Analysis (PCA) using PAST3 software.
The results showed each species of deer having their own unique antlers’ character,
and so it can be used to determine the species of Indonesian deer. The important
structures for identification are relief, pedicle, brow, bez, and main beam.
of deer forms specific antlers with specific size and
shape (Heffelfinger 2006).
Antlers attract human since ancient time. Most
of antlers were trade as trophy and displayed on the
wall. Some of it was processed into aphrodisiac or as
traditional medicine; however the efficacy is not
scientifically proven yet (Walrod, 2010). Species
identification of deer using antlers commonly based
on the size and shape of the complete antlers which
still attach to the skull (CITES, 2003). Some antlers
were traded separately or individually without its
skull, therefore it’s difficult to determine the species
origin.
Four of the native deer species in Indonesia
are an endemic species, i.e. Rusa timorensis, Axis
kuhlii, Muntiacus atherodes, and Muntiacus montanus.
Rusa timorensis and Rusa unicolor are considered
vulnerable by the IUCN Red list, while Axis kuhlii is
considered critically endangered. All the native deer
species of Indonesia is protected by the Indonesian
Government Regulation (2018), except for Muntiacus
montanus which couldn’t be evaluated yet. Even
though the deer of Indonesia are protected by the
law, some illegal hunting and antlers poaching is still
INTRODUCTION
Deer or cervids (family Cervidae) is one of the
families in the Artiodactyl groups which is second
most diverse member after bovids (family Bovidae)
(Prothero & Foss, 2007). Five valid species of
cervids are living and naturally distributed in
Indonesia, they are: Rusa timorensis (Javan rusa or
Sunda sambar), Rusa unicolor (Sambar), Axis kuhlii
(Bawean deer), Muntiacus muntjak (Indian muntjac,
southern red muntjac, barking deer) and Muntiacus
atherodes (Bornean yellow muntjac). Muntiacus
montanus from Sumatra might be another species of
deer in Indonesia, but not enough data had been
collected to evaluate the validity of this species.
Furthermore, there is one introduced species which
is Axis axis (chital, spotted deer or axis deer) (Goss,
1985; Bubenik & Bubenik, 1990; Stefoff, 2008;
Timmins et al., 2016).
One of the characteristics of deer is antlers on
individual male. Antlers are frontal bone which grow
outwards from frontal skull and usually called pedicle
(Price et al., 2005). The development of antlers is
influenced by several factors, among them are: age,
nutrition, and genetics. Consequently, each species
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J. Tropical Biodiversity Biotechnology, vol. 04 (2019), 97 — 106
happening in some places (Hedges et al., 2015;
Semiadi et al., 2015; Timmins et al., 2016a, 2016b).
An accurate way to identify antlers is needed to help
enforcing the law.
The purpose of this research is to identify
antlers’ morphological characters on each species to
be a diagnostic character. These diagnostic
characters can be an alternative of species
identification. The results were expected to assist the
species identification of antlers found without its
skull in trade market or fossils.
Those characters are shown on Table 1. Some
characters on Table 1, can only be measured if the
antlers are still intact with the skull. Characters
which need intact condition are: B (distance between
tips of main beams), C (greatest distance between
both antlers), and D (greatest distance between both
main beam’s inner side). Those characters should be
considered when identifying antlers, however it
couldn’t assist to identify shed, broken and
individual antlers.
MATERIALS AND METHODS
Materials
Materials used are deer antlers collection of the
Laboratory of Mammals Biosystematics, Museum
Zoologicum Bogoriense (MZB), Research Center for
Biology–Indonesian Institute of Sciences (LIPI).
Data were collected from 88 specimens; 86 of them
were antlers that are still intact with the skull. There
are 30 antlers of Muntiacus muntjak (15 skulls), 2
antlers of Axis axis (1 skull), 8 antlers of Axis kuhlii
(4 skulls), 12 antlers of Rusa unicolor (6 skulls), and 36
antlers of Rusa timorensis (17 skulls and 2 shed
antlers). A complete antler commonly consists of a
pedicle, burr, base, main beam, brow and bez (Figure 1).
Methods
The methods used was morphological comparison
of antlers characteristics and morphometric analysis
based on Boone & Crockett Club (1887) and
Semiadi et al. (2003). The morphological and
morphometric data acquired were then analysed
using Principal Component Analysis (PCA) with
software PAST3. PCA analysis was conducted to
exemine characters grouping in order to determine
its diagnostic characters. The characters used in this
research are shown on Table 1.
Antler’s relief is determined from five
categories. Smooth for antlers with no relief. Faint
for antlers with visible relief striation but couldn’t be
felt by touch. Weak for antlers with visible striation
and could be slightly felt by touch. Strong for antlers
with visible thick relief striation and could be felt by
touch. Pearled for antlers with strong relief and
pearly structure.
Figure 1. Antlers’ main part which are observed: A.
Pedicle, B. Burr, C. Base, D. Brow, E. Main beam 2nd
segment, F. Bez, G. Main beam 3rd segment, H. BeHt
(distance of bez branching to the base), I. BrHt (distance
of brow branching to the base).
Accessory on an antler is usually not the main
character for identification. Accessories are usually
just an abnormal growth of an antler. Therefore, the
presence of accessories should not be the main
consideration as a diagnostic character.
Diameter, perimeter, and length can be quite
significant characters for antler’s identification.
Nevertheless, along with those characters, other
characters should also be considered when
identifying antlers. Antler’s diameter and perimeter
will also increases along with the pedicle growth.
Pedicle will grow along with the skull’s growth,
meaning when an animal age increase, the size will
also increases. Each species of deer have their own
unique range of size, hence those characters could
RESULTS AND DISCUSSION
Antlers’ morphological characters
There are characters which are diagnostic of each
taxa. Some characters are qualitative and the rest are
binary (“present” or “absent”; value “1” or “0”).
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J. Tropical Biodiversity Biotechnology, vol. 04 (2019), 97 — 106
Table 1. Variation of antlers characteristics which can be diagnostic characters
No
1
Code
Re
Characters
Reliefs
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
PDt
Pdap
PP
BuDt
BuDap
BuP
BDt
Bdap
BP
M2P
M2Dt
M2Dap
M3P
M3Dt
M3Dap
ML
BrDt
BrDap
BrP
BrHt
BrAng
BrL
Be
BeDt
BeDap
BeP
BeHt
BeAng
BeL
B
C
D
PFl
M2Flb
BrFla
BrFlb
BrPa
BeMed
BeLat
AcH1
AcBr
AcM2
AcBe
Transversal diameter of pedicle
Anteroposterior diameter of pedicle
Perimeter of pedicle
Transversal diameter of burr
Anteroposterior diameter of burr
Perimeter of burr
Transversal diameter of base
Anteroposterior diameter of base
Perimeter of base
Perimeter of 2nd beam segment
Transversal diameter of 2nd beam segment
Anteroposterior diameter of 2nd beam segment
Perimeter of 3rd beam segment
Transversal diameter of 3rd beam segment
Anteroposterior diameter of 3rd beam segment
Main beam length
Transversal diameter of brow
Anteroposterior diameter of brow
Perimeter of brow
Brow branching distance to base
Brow branching angle
Brow length
Presencce of bez
Transversal diameter of bez
Anteroposterior diameter of bez
Perimeter of bez
Bez branching distance to base
Bez branching angle
Bez length
Distance between the tips of main beams
Greatest distance between both antlers
Greatest distance between both main beam’s inner side
Flattened pedicle
Laterolaterally flattened 2nd segment of main beam
Anteroposteriorly flattened brow
Laterolaterally flattened brow
Brow parallels to main beam
Bez grow inward
Bez grow outward
Accessory on branching of brow
Accessory on brow
Accessory on 2nd segment of main beam
Accessory on bez
Smooth
Faint
Weak
Strong
Pearled
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Data type
Level
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Binary
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Nominal
Binary
Binary
Binary
Binary
Binary
Binary
Binary
Binary
Binary
Binary
Binary
J. Tropical Biodiversity Biotechnology, vol. 04 (2019), 97 — 106
also be considered as diagnostic characters. The
length of antlers could vary during growth cycle of
antler. Old deer could also have a short antler if that
antler had just regrown after being shed at the
previous cycle. Besides that, in some cases, antlers
could also be broken when two males are fighting
each other on mating season or when it’s attacked by
other animals, including by humans (McPherson &
McPherson 2008). Therefore, the full length of the
antlers couldn’t be measured on some specimens.
meanwhile the other species of deer in Indonesia
have short and rounded pedicles. The brows are
flattened antero-posteriorly. The second segment of
main beam is flattened latero-laterally, especially on
its tip (Figure 5). Besides that, it is shown in the
Figure 2 that bez characters points away from the
Muntiacus muntjak group.
The antlers of Muntiacus doesn’t have bez,
hence the bez character in the Muntiacus muntjak
group will always be 0. The absence of bez is a
significant character to differentiate Muntiacus with
the other groups of deer in Indonesia (Figure 5).
In Indonesia, Muntiacus genus is not only
represented by Muntiacus muntjak, but also Muntiacus
atherodes. In LIPI, there is no antler collection of
Muntiacus atherodes, therefore analysis couldn’t be
done to differentiate between the antlers of
Muntiacus muntjak and Muntiacus atherodes.
The Axis group is scattered in the lower
quadrant (Figure 2). It is shown that the characters
which support this group are BeMed (bez grows
inward) and BrPa (brow parallel to main beam). All
of the species in the Axis genus in Indonesia have
bez that grow inward (Figure 6). This character is
also present in Rusa unicolor. Axis group tend to have
brows which grow parallel to the main beam. Re
(relief) character on the scatter plot points away
from the Axis group. Compared to the other deer
groups in Indonesia (represented on Figure 2), genus
Axis have antlers with a relatively weak relief. Genus
Axis also has cylindrical and slim antlers, meanwhile
the Muntiacus have a flattened short antlers (shown in
Figure 5) and the Rusa have a large rugose antlers
(see Figure 7 and 8).
On the scatter plot in Figure 2, Axis axis
groups located on the outer edge of Axis kuhlii’s
groups. The fewer numbers of Axis axis specimen
available for analysis may result in an unfavourable
grouping on the scatter plot. Axis axis is not a native
animal in Indonesia. Axis axis in Indonesia was
introduced from the middle Asia (Stefoff, 2008).
Axis axis in Indonesia could only be found in the
manmade areas, such as the Bogor Palace (Istana
Bogor) and zoos. Therefore, the specimens obtained
were in low numbers.
Generally, Axis axis antler’s is longer than
Axis kuhlii’s. Furthermore, the antlers of Axis axis
have bez that tends to grow slightly upwards
(forming a U-shape), meanwhile in Axis kuhlii it
tends to grow straight (forming an L-shape) (Figure
7).
The group of genus Rusa is scattered on the
right side of the quadrant (Figure 2). Characters
which support this grouping are diameter and
circumference of antlers. Compares to the other
groups, genus Rusa generally have a bigger antler.
Antler specimens of Indonesian deer
Principal Component Analysis was conducted from
the data collected. The correlation analysis between
group results in eigenvalues and percent variances
shown in Table 2, while the scatter plot can be seen
in Figure 2 as follows.
The results shown in Figure 2, were the data
of antlers analysed in which the antlers were not
attached to the skull anymore. Some characters i.e. B
(tip to tip distance), C (greatest distance between
both antlers), and D (greatest distance between both
antlers’ inner side) is not included in that PCA due
to isolated antlers. The antlers analysed in Figure 2
were only one side and not attached to the skull,
therefore it is impossible to measure. Some groups
show wide range in the PCA scatter plot, it indicates
variance on the characters. This was caused by the
difference in condition of the antlers used in
analysis. Some specimens was just started its adult
stage which was indicated by the size of the skull and
mainly its pedicle, meanwhile some specimens have
reached its maximal size. Some antlers undergo
abnormality in its growth which altered the antler’s
proportion. Nevertheless, each species group could
be shown on the scatter plot and have a quite
significant distance between each other. The loading
plot of component 1 can be seen as follows on
Figure 3, while the loading plot of component 2 can
be seen on Figure 4.
Table 2. Eigenvalue and % Variance
PC
Eigenvalue
% Variance
1
24.1244
73.104
2
4.83482
14.651
3
2.55828
7.7524
4
1.48246
4.4923
The Muntiacus muntjak group is separated by a
great distance from the other groups (Figure 2). This
grouping is supported by some characters, namely
BrFla (brow flattened anteroposteriorly), PFl
(pedicle flattened laterolaterally), and M2Flb (2nd
segment of main beam flattened laterolaterally).
Muntiacus muntjak have a long and flattened pedicle,
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J. Tropical Biodiversity Biotechnology, vol. 04 (2019), 97 — 106
RT : Rusa timorensis
RU : Rusa unicolor
AA : Axis axis
AK : Axis kuhlii
MM : Muntiacus muntjak
Figure 2. The PCA results of individual antlers.
Figure 3. The loading plot of component 1
Rusa unicolor’s group is supported by some
characters, which are: the combination of BeAng
(bez branching angle), BeHt (distance of bez
branching to base), BrHt (distance of bez branching
to base), also characters of the diameter and
circumference which generally support the Rusa
group. Rusa unicolor can be differentiated from Rusa
timorensis by some characters, especially BeMed (bez
grows inward), where Rusa unicolor have bez that grow
inward just like those in Axis kuhlii. Bez of Rusa
unicolor’s antlers also tend to grow straight just like
Axis kuhlii’s, but they can be differentiated by some
characters. Rusa unicolor have higher BrHt value,
while Axis kuhlii have lower BrHt value. Rusa
unicolor’s antlers also have stronger relief than Axis
kuhlii’s, Rusa unicolor also have larger bez while Axis
kuhlii’s are relatively slender (Figure 8).
Rusa timorensis group is supported by some
characters, namely Re (relief), BeLat (bez grows
outward), M2Dap (anteroposterior diameter of main
beam’s 2nd segment), BP (perimeter of base), and
M2P (perimeter of main beam’s 2nd segment). Rusa
timorensis’s antlers tend to have pearled relief. Among
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Figure 4. The loading plot of component 2
seen that the Axis axis’s and Axis kuhlii’s group
become distinctly separated. Axis axis’s antlers tend
to spread widely, where Axis kuhlii’s tend to grow
upward. This causes the distance between antlers in
Axis axis to be wider than those of Axis kuhlii’s,
hence Axis axis have greater value of B, C, and D.
On larger specimens (which couldn’t be found in
LIPI’s collection), Axis axis’s antlers grows
significantly wider than shown in the PCA result (see
Figure 11).
Indonesian deer, Rusa timorensis is the only one
whose bez grows outward (represented on Figure 2).
Table 3. Eigenvalue and % Variance of paired antler
specimens’ PCA
PC
Eigenvalue
% variance
1
28.3827
72.776
2
5.29825
13.585
3
3.10356
7.9579
4
2.21546
5.6807
On the Rusa group (Figure 10), changes occur
by which the groups become more clumped
together. The changes happen because in the Rusa
group, the specimens used were highly varied in
terms of their ages and phases in the growth cycle;
hence the variance of size is high. While the sizes
vary highly between age groups, the distance
between antlers tend to be the same, hence the low
variance of distance between antlers’ characters
makes the scatter plot become more clumped. The
distance between Rusa timorensis’s and Rusa unicolor’s
group also decreases. This was caused by the
relatively equal antlers’ average circumference and
diameters of both species.
It should also be noted that in its growth,
Figure 5. Muntiacus muntjak specimen, left: dorsal view
and right: lateral view, with description: A. Pedicle, B.
Burr, C. Brow, D. 2nd segment of main beam.
PCA results on Figure 10 was an analysis of
paired antlers. In this analysis, character B (tip to tip
distance), C (greatest distance between antler), and D
(greatest distance of main beam’s inner side) was
included in the analysis. By including B, C, and D
characters, some changes can be seen on the scatter
plot shown on figure 10. The eigenvalue and %
variance is shown on Table 3.
On the Axis group (Figure 10), changes can be
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Figure 6. Comparison of Muntiacus muntjak and Rusa unicolor antlers. Muntiacus muntjak antlers don’t have bez.
Figure 7. Specimens of Axis group: Axis axis (left) and Axis kuhlii (right), with description: A. Pedicle, B. Burr, C.
Brow, D. 2nd segment of main beam, E. Bez, F. 3rd segment of main beam.
Figure 8. Antler comparison of Rusa unicolor (left) and Axis kuhlii (right).
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Figure 9. Specimens of Rusa unicolor (left) and Rusa timorensis (right), with description: A. Pedicle, B. Burr, C. Brow, D.
2nd segment of main beam, E. Bez, F. 3rd segment of main beam.
RT : Rusa timorensis
RU : Rusa unicolor
AA : Axis axis
AK : Axis kuhlii
MM : Muntiacus
muntjak
Figure 10. PCA result of paired antler specimens.
antler could experience abnormality or damage. The
abnormality in antler’s growth and damage can alter
the shape and size of the antler. The branch which is
not normally present in the antler is called
“abnormal” or “accessory”. Antlers growth can also
be faster or slower in some individuals. The
alteration of growth speed can also alter the
maximum size of antlers. Therefore, some
individuals of the species can have a different
antler’s characteristic from the one described in this
article.
Diagnostic characters of antlers for each species
Based on the analysis, it can be seen that each group
is separated from the others. That grouping is
supported by some characters. The characters which
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J. Tropical Biodiversity Biotechnology, vol. 04 (2019), 97 — 106
Figure 11. Comparison of antler’s distance in Axis axis (left) and Axis kuhlii (right)
Table 4. Diagnostic characters of the antlers.
No Species
Characters
1
Muntiacus muntjak
Brow as the only branch
Pedicle long and flattened
Main beam flattened laterolaterally
Brow flattened anteroposteriorly
Low BrHt
Relief weak to strong
2
Axis axis
Relatively widely curved
3
4
5
Axis kuhlii
Rusa unicolor
Rusa timorensis
BrHt intermediate
Brow angle intermediate
Bez grows inward
Low bez angle
Weak relief
Relatively upright
BrHt intermediate
Brow angle intermediate
Bez grows inward
Relatively high bez angle
Weak relief
Large diameter
Bez grows inward
Bez angle intermediate
Brow angle intermediate
High BrHt
Extensions on branching
Strong relief
Large diameter
Bez grows outward
Bez angle intermediate
Brow angle intermediate
Extensions on branching
Relief mostly pearled
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Remarks
Especially on the tip
Does not flattened on some individuals
0.7–2 cm
Not significant in some individuals, especially
young ones
3–4 cm
Approximately 50°
Around 35–40°, forms U-shape
3–4 cm
Approximately 50°
Around 60–70°, forms L-shape
Usually > 2cm
Around 45–65°
Around 40–55°
Around 5–8 cm
Especially on brow, forms area connecting
brow and main beam
Pearled in some individuals
Usually > 2cm
Around 50–70°
Around 35–60°
Especially on bez, forms area connecting bez
and main beam
No pearl but have strong relief in some
individuals
J. Tropical Biodiversity Biotechnology, vol. 04 (2019), 97 — 106
supported a certain group become that group’s
diagnostic characters shown on Table 4.
Ministry of Environment and Forestry, 2018, P.20/
MENLHK/SETJEN/KUM.1/6/2018.
Price, J.S., Allen, S., Faucheux, C., Althnaian, T., &
Mount, J.G., 2005, Deer Antlers: A Zoological
Curiosity or the Key to Understanding Organ
Regeneration in Mammals?, Journal of Anatomy
207, 603–618.
Prothero, D.R. & Foss, S.E., 2007. The Evolution of
Artiodactyls, John Hopkins University Press,
Baltimore, pp. 249–250.
Semiadi, G., Duckworth, J.W. & Timmins, R, 2015,
Axis kuhlii. The IUCN Red List of Threatened
Species 2015: e.T2447A73071875, viewed 2
September 2019. http://dx.doi.org/10.2305/
IUCN.UK.2015-2.RLTS.T2447A73071875.en.
Semiadi, G., Subekti, K., Sutama, I. K., Masy’ud, B.,
& Affandy, L., 2003. Antler’s Growth of the
Endangered and Endemic Bawean Deer (Axis
kuhlii Müller & Schlegel, 1842), Treubia 33(1),
89–95.
Stefoff, R., 2008, Deer, Marshall Cavendish, New
York, pp. 47–55.
Timmins, R.J., Belden, G., Brodie, J., Ross, J.,
Wilting, A. & Duckworth, J.W, 2016a,
Muntiacus atherodes. The IUCN Red List of
Threatened Species 2016: e.T42189A22166396,
viewed 2 September 2019. http://
dx.doi.org/10.2305/IUCN.UK.2016 2.RLTS.T42189A22166396.en.
Timmins, R.J., Duckworth, J.W. & Groves, C.P.,
2016b, Muntiacus montanus. The IUCN Red List
of Threatened Species
2016:
e.T136831A22168363, viewed 2 September
2019. http://dx.doi.org/10.2305/
I U C N . U K . 2 0 1 6 1.RLTS.T136831A22168363 .en.
Walrod, D., 2010, Antlers: A Guide to Collecting,
Scoring, Mounting, and Carving, Stackpole Books,
Mechanicsburg, pp. 4–6, 83–85.
CONCLUSION
Based on the research, it can be concluded that
antler’s characters could become diagnostic
characters to identify cervids species. The diagnostic
characters are pedicle, main beam, relief, brow, bez,
and diameter of the antlers. Muntiacus atherodes’s and
Muntiacus montanus’s antlers need to be analysed to
distinguish it from Muntiacus muntjak.
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