Extending the utility of artiodactyl postcrania for species-level identifications using multivariate morphometric analyses

Abstract

Studies of paleoecology are most powerful when relative abundance data are available at fine taxonomic scales and large sample sizes. Postcranial elements are abundant but seldom identified to species, reducing potential sample size. We investi-gate whether antilocaprid astragali, abundant in the Late Miocene deposits of the Great Basin, can be identified to species, improving sample sizes. Our analysis of African and Asian bovid data from the literature suggests species should be distinguishable using astragalar dimensions. For our case study we use three species of antilocaprids, Ilingoceros alexandrae, Ilingoceros schizoceras, and Sphenophalos nevadanus from the Hemphillian (~8 Ma) Thousand Creek Fauna of northwestern Nevada. These spe-cies are diagnosed by their horncores, but previous comparisons of their dentition have shown no clear separation between the species. Our analysis of >200 antilocaprid astragali from Thousand Creek indicates there is enough variation to tentatively reject the hypothesis of only one species, but the distribution does not allow assignment of individual astragali to species. Combined with horncore morphology, our results sug-gest differences in male-male competition and a slight difference in body size kept the two genera out of competition while ecological similarity and/or shared ancestry cre-ated a continuous distribution of astragalar dimensions. The data cannot resolve whether I. alexandrae and I. schizoceras are distinct species. Additionally, we explored the range of effectiveness of a published discriminant function developed to derive environmental preference from African bovid astragali. Applying this discriminant func-tion to Antilocapra proved ineffective, likely a consequence of the distinct evolutionary histories of antilocaprids and bovids.

Full text

Palaeontologia Electronica
http://palaeo-electronica.org
PE Article Number: 15.1.1A
Copyright: Society of Vertebrate Paleontology January 2012
Submission: 16 November 2010. Acceptance: 4 July 2011
Davis, Edward Byrd and Calède, Jonathan Jean-Michel. 2012. Extending the utility of artiodactyl postcrania for species-level
identifications using multivariate morphometric analyses. Palaeontologia Electronica Vol. 15, Issue 1; 1A:22p;
palaeo-electronica.org/content/2012-issue-1-articles/68-artiodactyl-postcrania
Extending the utility of artiodactyl postcrania for species-level
identifications using multivariate morphometric analyses
Edward Byrd Davis and Jonathan Jean-Michel Calède
ABSTRACT
Studies of paleoecology are most powerful when relative abundance data are
available at fine taxonomic scales and large sample sizes. Postcranial elements are
abundant but seldom identified to species, reducing potential sample size. We investi-
gate whether antilocaprid astragali, abundant in the Late Miocene deposits of the Great
Basin, can be identified to species, improving sample sizes. Our analysis of African
and Asian bovid data from the literature suggests species should be distinguishable
using astragalar dimensions. For our case study we use three species of antilocaprids,
Ilingoceros alexandrae, Ilingoceros schizoceras, and Sphenophalos nevadanus from
the Hemphillian (~8 Ma) Thousand Creek Fauna of northwestern Nevada. These spe-
cies are diagnosed by their horncores, but previous comparisons of their dentition have
shown no clear separation between the species. Our analysis of >200 antilocaprid
astragali from Thousand Creek indicates there is enough variation to tentatively reject
the hypothesis of only one species, but the distribution does not allow assignment of
individual astragali to species. Combined with horncore morphology, our results sug-
gest differences in male-male competition and a slight difference in body size kept the
two genera out of competition while ecological similarity and/or shared ancestry cre-
ated a continuous distribution of astragalar dimensions. The data cannot resolve
whether I. alexandrae and I. schizoceras are distinct species. Additionally, we explored
the range of effectiveness of a published discriminant function developed to derive
environmental preference from African bovid astragali. Applying this discriminant func-
tion to Antilocapra proved ineffective, likely a consequence of the distinct evolutionary
histories of antilocaprids and bovids.
Edward Byrd Davis. Department of Geological Sciences and Museum of Natural and Cultural History,
University of Oregon, Eugene, Oregon, 97403–1272, USA. edavis@uoregon.edu
Jonathan Jean-Michel Calède. Department of Biology, University of Washington, Seattle, Washington,
98195-1800, USA. caledj@uw.edu
KEY WORDS: discriminant analysis; CV; Antilocapridae; Bovidae; habitat; abundance

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
2
INTRODUCTION
Large-scale studies of mammalian diversity
and evolution (e.g., Alroy et al., 2000; Barnosky et
al., 2005) require large numbers of fine-scale taxo-
nomic identifications; consequently, one of the pur-
poses of new alpha taxonomy in paleontology
should be to offer the largest, best supported data-
set for future diversity and evolutionary studies. In
particular, relative abundance analyses, important
for understanding local, regional, or even global
scale changes in faunas (Shotwell, 1963; Krause,
1986; Olzewski, 2004; Davis, 2005; Davis and
Pyenson, 2007), require large sample sizes for the
number of identified specimens (NISP) or the mini-
mum number of individuals (MNI). The rich fossil
record of the Great Basin is a critical dataset in the
study of mammalian paleoecology in the Cenozoic
(Barnosky et al., 2005; Davis, 2005; Kohn and
Fremd, 2008), but most mammalian fossil deposits
in the Great Basin consist primarily of fragmentary
postcranial elements, with rare preservation of
skulls (Davis and Pyenson, 2007). The preserva-
tion of teeth is enough for fine taxonomic resolution
in most mammal groups, but for one group of artio-
dactyls, the Antilocapridae, taxa are only identified
using horncores. Those horncores are extremely
rare in Great Basin deposits even though both
males and females bear horns within the Antilo-
caprinae (including Ilingoceros, Sphenophalos,
and Texoceros), as opposed to the more basal
merycodontine antilocaprids.
Despite their abundance, postcranial ele-
ments have seldom been used to identify antilo-
caprid taxa at the species level; consequently, a
large number of fossil remains are ignored when
analyzing antilocaprid diversity in the Late Miocene
deposits of the Great Basin, a time period critical to
understanding both overall faunal response to cli-
mate change (Alroy et al., 2000; Barnosky et al.,
2005; Kohn and Fremd, 2008; Finarelli and Badg-
ley, 2010) and the decline of antilocaprids to a sin-
gle extant species (Janis and Manning, 1998;
Davis, 2007). We explore whether artiodactyl
astragali will allow species-level identification. If so,
artiodactyl astragali, commonly preserved in the
Late Miocene deposits of the Great Basin, will be
able to provide a robust and abundant data source
for analyses of Great Basin community paleoecol-
ogy and evolution, adding substantially to our
knowledge of paleoecology. We focus on antilo-
caprids here, but the method shows some promise
for extensions to camelids as well (Breyer, 1983;
Davis, 2004).
FIGURE 1. Photographs of fossil antilocaprid horns. 1.1, Ilingoceros schizoceras; 1.2, I. alexandrae; 1.3, Spheno-
phalos nevadanus.

PALAEO-ELECTRONICA.ORG
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As our case study, we use the antilocaprids
from the early early Hemphillian (Hh1) Thousand
Creek Fauna (~7–8 Ma, Perkins et al., 1998; Pro-
thero and Davis, 2008) of northwestern Nevada.
This fauna contains a diversity and abundance
fauna of large mammals, including two genera of
antilocaprids (Davis 2007) but no dromomerycids
or other ruminants (Merriam, 1911; Frick, 1937;
Janis et al., 1998; Carrasco et al., 2005). The spe-
cies of antilocaprids from Thousand Creek include
Ilingoceros alexandrae Merriam, 1909, Ilingoceros
schizoceras Merriam, 1911, and Sphenophalos
nevadanus Merriam, 1909 (Figure 1). Merriam and
Stock (1928) first suggested a close evolutionary
relationship for the genera, and current thinking still
supports the two as sisters (Janis and Manning,
1998). Frick (1937) illustrated a large range of vari-
ation in horncores of Ilingoceros and proposed that
I. schizoceras was a female or juvenile of I. alexan-
drae, but no one has subsequently treated these
two species.
Although these three names have become
established in the literature, efforts to diagnose the
species on the basis of anything but horncores
have been futile. Merriam (1911) attributed two
large molars to S. nevadanus, and several small
postcrania to I. schizoceras, arguing that S. neva-
danus horncores belonged to a larger animal than
Ilingoceros. However, Stirton (1932) analyzed all
the antilocaprid teeth from Thousand Creek and
concluded Ilingoceros and Sphenophalos were
indistinguishable from dentition. Consequently, he
argued, the two genera might be too closely related
to be distinguished by dental morphology or size,
or might represent the male and female of a single
species. No postcrania have been found directly
associated with horncores at Thousand Creek, pre-
venting definitive species assignment of any speci-
mens except horncores; consequently, NISPs and
MNIs are two orders of magnitude lower than their
potential.
Fossil remains from other regions have shed
some light on Ilingoceros and Sphenophalos rela-
tionships. The presence of Sphenophalos without
Ilingoceros in two other sites (Furlong, 1932; Bar-
bour and Schultz, 1941) removes support for the
two as sexual dimorphs, but small sample sizes
(five and one) decrease the power of this argu-
ment. A seasonal bias in preservation might have
captured only one sex in one locality, but coinci-
dence in two geographically distant sites (Oregon
and Nebraska) seems less likely. There are no
records of Ilingoceros outside of Thousand Creek.
Typical of many Great Basin Miocene fossil
mammal localities, the Thousand Creek Formation
is composed of tuffaceous sedimentary rocks with
locally distributed pumice and ash layers (Green,
1984). The mammal fauna is represented mostly
by postcrania, with a majority of podial elements,
deposited close to the shores of one or more lakes
where scavenging occurred before burial (Davis
and Pyenson, 2007). Establishing a new way to
identify antilocaprid (or other artiodactyl) species
from isolated podials would dramatically increase
the sample size available for paleoecological anal-
ysis from this and other taphonomically similar
Great Basin Miocene sites. To that end, we have
used multivariate techniques to describe the mor-
phological diversity of antilocaprid astragali from
the abundant postcranial remains recovered from
Thousand Creek, with the goal of assessing the
number of antilocaprid species present in the
fauna.
We have grounded our paleobiological analy-
sis in neo-biological data, building upon an investi-
gation of African antelope astragali. The
discriminant function analysis (DFA) of DeGusta
and Vrba (2003) has shown promise for diagnosing
ecological differences from the morphology of
artiodactyl astragali. Analyzing eight morphological
dimensions of the astragali of bovid antelope,
DeGusta and Vrba (2003) were able to discrimi-
nate among four habitat preferences with a preci-
sion of 67% (p<0.0001). That significant success
for habitat preferences suggested to us the poten-
tial for similar success in discriminating species
from astragali. If the modern antelope data from
DeGusta and Vrba (2003) were to contain enough
taxonomic information to allow species-level diag-
nosis, it should be possible to similarly diagnose
the extinct antilocaprid species from Thousand
Creek. To test our hypotheses regarding species-
level diagnosis on the basis of astragalar shape,
we performed a new by-species DFA using the
data from the by-habitat DFA of DeGusta and Vrba
(2003). Additionally, to provide a large baseline for
artiodactyl astragalus variation, we compared the
coefficients of variation for the species from
DeGusta and Vrba (2003) as well as Weinand
(2007) to three groups: modern Antilocapra ameri-
cana, a fossil sample known to be a single species
(Texoceros guymonensis from the Optima fauna of
Oklahoma), and the unknown sample of antilo-
caprid astragali from Thousand Creek, Nevada.

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
4
MATERIALS AND METHODS
Material Examined
In addition to the bovid data from DeGusta
and Vrba (2003) (n=218) and Weinand (2007)
(n=81), we analyzed measurements from 26 mod-
ern Antilocapra americana and 290 fossil antilo-
caprid astragali (223 from Thousand Creek and 67
from Optima). Thousand Creek astragali come
from the University of California Museum of Pale-
ontology (UCMP) (n=136) and the Los Angeles
County Museum (LACM) (n=87) (Appendix 1).
Optima astragali, assigned to Texoceros guymon-
ensis Frick (1937), are included as a control. These
specimens, from the Frick Collection of the Ameri-
can Museum of Natural History (F:AMNH), are
from the type locality of the species, the Optima
local fauna (Frick, 1937; Schultz, 2002) in the Guy-
mon area of Texas County, Oklahoma. The T. gu y -
monensis sample provides a control distribution for
a single species of closely related antilocaprid.
Modern Antilocapra americana astragali from the
collections of the University of California Museum
of Vertebrate Zoology (MVZ) provide a single-spe-
cies control distribution from a closely related mod-
ern population. To obtain the largest sample
possible, we included specimens from the entire
geographic range of the species, making the com-
parison with the Thousand Creek sample more
conservative, because the geographic variation of
our sample must have higher variance than a mod-
ern single-locality population. Adult astragali can-
not be differentiated from juveniles because they
fuse early on in an individual’s life. As a conse-
quence, the specimens of fossil antilocaprids mea-
sured might include some juveniles.
Body Mass and Comparisons of
Coefficients of Variation
The coefficient of variation (V, standard devia-
tion divided by the mean) is a unit-free measure of
dispersion that has been suggested to allow com-
parisons among organisms of different sizes (Car-
rasco, 1998). It should therefore be possible, using
coefficients of variation, to compare morphometric
measurements of animals with very different body
masses. However, when comparing the coeffi-
cients of variation of the astragali measurements of
modern bovids, it became apparent to us that a
positive correlation remains between body mass
and coefficient of variation, indicating that the met-
ric does not remove all of the influences of size.
The relationship between V and mass is significant
for the three measurements of length of the astrag-
alus (LM, LI, and LL) as well as one of the mea-
surements of height (TI), indicating an allometric
effect on the variation in length (and somewhat on
height) of the astragalus.
Therefore, when comparing the Vs of Thou-
sand Creek antilocaprids (Ilingoceros and Sphe-
nophalos) to modern species, we need to account
for body size. To this end, we only compared the
fossil antilocaprids to extant bovids of similar sizes.
To compare fossil antilocaprids to extant bovids of
similar mass, we calculated the average body
mass of the genera Ilingoceros and Sphenophalos
using the all-ruminant regression of Janis (1990).
Average lengths of m2 for both genera were taken
from Janis and Manning (1998). Body mass for
FIGURE 2. Illustration of idealized antilocaprid astragalus, indicating the eight dimensions used in this analysis, fol-
lowing DeGusta and Vrba (2003). 2.1, anterior view; 2.2, lateral View; 2.3, medial view. Abbreviations: LM= medial
length; LI= intermediate length; LL= lateral length; TD= distal thickness; TI= intermediate thickness; TP= proximal
thickness; WD= distal width; WI= intermediate width.

PALAEO-ELECTRONICA.ORG
5
extant taxa were obtained from the mammalian
peer-reviewed literature (Nowak, 1999; Skinner
and Smithers, 1990).
Data Acquisition
The dimensions of fossil astragali we mea-
sured are identical to those of DeGusta and Vrba
(2003). The eight dimensions analyzed by
DeGusta and Vrba (2003) describe the important
details of the length, width, and thickness of the
proximal and distal trochleae of the astragali (Fig-
ure 2). Dimensions were recorded to the nearest
0.01mm using Mitutoyo Absolute Digimatic CD-6”C
calipers, except for the MVZ and LACM speci-
mens, which, because of tool availability, were
measured with less precise Carrera Precision 6"
dial calipers, recording dimensions to 0.05 mm. To
eliminate inter-operator error, all specimens were
measured by EBD. To determine intra-operator
error, EBD remeasured 39 specimens from UCMP,
with four weeks between measurements.
All statistical analyses were rerun without the
data from the LACM collections (measured with the
less precise calipers), and differences in results are
reported where they are present.
Data Analysis
We analyzed the eight dimensions of the
astragali using the statistical package JMP (Ver-
sion 8.0.2, SAS Institute) and formulas written in
MS Excel. The distributions of the data were ana-
lyzed for each of the eight individual characters
using the Shapiro-Wilk W test of normality (Shapiro
and Wilk, 1965) and for the entire group of mea-
surements using a principal components analysis.
If the Thousand Creek antilocaprids segregated by
size, it might be represented by a multimodal distri-
bution in the first principal component (size and
size-related shape differences) or in the original
measurements of the astragalar dimensions. If, on
the other hand, they had little size difference, they
might still segregate by astragalus shape, which
would be distinguishable in the first and second
principal components, which would represent size-
related and size-independent differences, respec-
tively, in shape across the sample (Hammer and
Harper, 2006). A truly multimodal distribution is
only rarely distinguishable in these sorts of continu-
ous data (Carrasco, 2004), so the failure to distin-
guish a distribution from normal should not be seen
as a rejection of the alternate hypothesis: it only
means that new specimens cannot be identified
using an a priori distinction based on size.
To test the potential for these multivariate data
to distinguish two closely related species, we sub-
jected the DeGusta and Vrba (2003) African ante-
lope data to a discriminant function analysis (DFA)
on the basis of specific identification. Additionally,
we performed individual DFAs within genera of
African antelope, to detect the sensitivity of the
astragalar dimensions to species-level differences
within a genus. While these DFAs are not identical
to the PCA we performed on the Thousand Creek
data, they do provide a baseline for taxonomic dis-
crimination using artiodactyl astragali. Unfortu-
nately, we cannot perform such a DFA on extant
antilocaprids because there is only the single
extant species.
If there are two or three species of antilo-
caprids in the fossil sample, the V will be larger in
the fossil sample from Thousand Creek than in the
single-species samples of Antilocapra americana,
Texoceros guymonensis, or the samples published
by DeGusta and Vrba (2003) or Weinand (2007)
(Simpson, 1947; Sokal and Braumann, 1980; Car-
rasco, 1998). To test this prediction, we followed
the methods for comparing V presented by Sokal
and Braumann (1980), using V*, the coefficient of
variation corrected for sample size. This correction
is small and, although arguments have been pre-
sented against it on the basis that it increases the
estimate of variation (Cope and Lacy, 1992; Cope,
1993), it does not change the results (Table 1) of
this study and has been used here for consistency
with the method of Sokal and Braumann (1980). To
remove erroneously high V* values, we only
included single-species samples from DeGusta
and Vrba (2003) and Weinand (2007) with sample
sizes greater than five individuals.
If coefficients of variation between the Thou-
sand Creek sample and the single species sam-
ples are not significantly different, we cannot reject
the null hypothesis that the Thousand Creek antilo-
caprids are members of a single species. If there
are no detectible differences within the sample of
astragali from Thousand Creek through both (1)
exploration of the data using principal components
analysis and (2) hypothesis testing using the analy-
sis of coefficients of variation, we will be unable to
reject the null hypothesis of a single species.
We also considered analyzing the Thousand
Creek dataset using the environmentally-based
discriminant function for bovid astragali developed
by DeGusta and Vrba (2003). Before we could take
that step, we first had to test whether the bovid
antelope discriminant function would give sensible
results when applied to a known species of antilo-

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
6
caprid. Consequently, we analyzed our measure-
ments of A. americana using the bovid antelope
discriminant function (Appendix 2).
RESULTS
Intra-Operator Error
Reassuringly, the intra-operator error is much
smaller than the differences in size critical to the
analysis. There was a maximum disparity of 2.32
mm (13%) between individual measurements (for
distal thickness of UCMP 153964), but overall
average disparity was only 0.24 mm (1%). Distal
thickness (TD) was the most variable dimension,
with an average difference of 0.65 mm (4%).
Although we did not attempt to estimate dimen-
sions from missing parts of specimens, the distal-
lateral corner of many astragali was abraded in a
way that made the bone surface irregular. These
irregular surfaces contributed to the large intra-
operator error for TD. The average disparities for
the other seven measurements were less than 3%,
an acceptable level for this analysis (Table 2),
because these differences represent on the order
of 10% (for most of the dimensions) of the standard
deviation for the Thousand Creek sample.
TAB L E 1 . Summary statistics of astragali samples.
1 Significance of deviation from normal distribution using a Shapiro-Wilk test.
2 Coefficient of Variation.
3 V corrected for sample size.
4 Standard Error of V*.
n mean std dev S-W1V2V *3 SV* 4
Thousand Creek
LM 190 27.83 1.71 n.s. 0.0614 0.0615 0.0032
TD 211 13.99 1.25 n.s. 0.0893 0.0895 0.0044
TI 216 15.30 1.27 n.s. 0.0830 0.0831 0.0040
TP 212 11.06 0.97 n.s. 0.0877 0.0878 0.0043
LL 198 30.51 2.05 n.s. 0.0672 0.0673 0.0034
WD 193 18.62 1.59 0.0153 0.0854 0.0855 0.0044
WI 201 17.71 1.60 n.s. 0.0903 0.0905 0.0046
LI 215 23.88 1.58 n.s. 0.0662 0.0662 0.0032
Antilocapra americana
LM 26 34.15 1.24 n.s. 0.0363 0.0367 0.0052
TD 24 16.70 1.02 n.s. 0.0611 0.0617 0.0092
TI 25 18.81 0.84 n.s. 0.0447 0.0451 0.0066
TP 26 13.90 0.63 n.s. 0.0453 0.0458 0.0065
LL 25 36.72 1.44 0.0039 0.0392 0.0396 0.0058
WD 26 21.91 0.80 0.0428 0.0365 0.0369 0.0053
WI 26 22.39 1.04 n.s. 0.0464 0.0469 0.0067
LI 25 28.93 1.06 0.0357 0.0366 0.0370 0.0054
Texoceros
guymonensis
LM 67 22.75 1.02 n.s. 0.0448 0.0450 0.0039
TD 67 11.51 0.96 n.s. 0.0834 0.0837 0.0074
TI 67 12.49 0.91 n.s. 0.0729 0.0731 0.0064
TP 67 9.39 0.65 n.s. 0.0692 0.0695 0.0061
LL 67 24.95 1.19 n.s. 0.0477 0.0479 0.0042
WD 67 15.23 0.90 n.s. 0.0591 0.0593 0.0052
WI 65 14.46 1.10 n.s. 0.0761 0.0764 0.0068
LI 65 19.92 1.08 n.s. 0.0542 0.0544 0.0048
TABLE 2. Intra-operator error for astragalar dimensions.
Dimension Difference
(mm)
Difference
(%)
LM 0.12 0.4
TD 0.65 4.5
TI 0.36 2.3
TP 0.14 1.3
LL 0.11 0.4
WD 0.15 0.8
WI 0.24 1.3
LI 0.12 0.5

PALAEO-ELECTRONICA.ORG
7
Similarly low relative errors were found in a
comparison between measurements taken with the
coarse (0.05 mm) and fine (0.01 mm) calipers.
EBD measured 47 UCMP specimens with both
sets of calipers to quantify the loss in precision with
the coarser calipers. Average disparity between
measurements at 0.01 mm and 0.05 mm precision
was 0.32 mm, comparable to the intra-operator
error for the more precise calipers.
Taxonomic Discriminant Function Analysis of
African Bovid Data
For the overall DFA, including all African bovid
specimens, the analysis was able to correctly dis-
criminate 82.11% of specimens at the species
level. In comparison, DeGusta and Vrba (2003)
were only able to get 67% correct for their four hab-
itat categories. DFAs within Cephalophus, Conno-
chaetes, Damaliscus, Oryx, and Redunca correctly
distinguished all individuals; only in Kobus and
Tragelaphus were there incorrect assignments. In
Kobus, only one out of the 18 specimens was mis-
classified (Kobus megaceros placed in Kobus kob),
for a 94.4% success rate. In Tragelaphus, six out of
51 specimens were misclassified (one Tragelaphus
euryceros as Tragelaphus strepiceros; one Trage-
laphus scriptus as Tragelaphus spekei; and three
Tragelaphus strepiceros, one as Tragelaphus
angazi and two as Tragelaphus euryceros) for an
88.24% success rate.
Habitat Discriminant Function Applied to
Antilocapra americana
The results of the bovid discriminant function
analysis on Antilocapra americana (n=26) included
estimated body weight and predicted habitat. The
habitat classification used follows Kappelman et al.
(1997). Results yielded three individuals (six ele-
ments; three right and three left astragali) with a
predicted habitat for the right astragalus different
from that predicted for the left one within the indi-
vidual (Appendix 2). In addition, all four habitat
classes were predicted for at least one of the
included specimens.
Principal Components Analysis
Examination of the principal components plot
reveals no evidence that the distribution of Thou-
sand Creek astragali is multimodal in any of the
first three components (Figure 3). The first compo-
nent of the PCA (PC1) accounts for 81.59% of the
variation, PC2 accounts for 5.27%, and PC3 for
4.38% (Table 3). Examination of the relative
weights of the principal components indicates that
because all the loads on PC1 are positive and
equal, we can interpret it as changes in size (Ham-
mer and Harper, 2006).
FIGURE 3. Principal components plots of Thousand Creek Antelope data. 3.1, PC1 versus PC2; 3.2, PC2 versus
PC3.

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
8
The first principal component (PC1) explains
82% of the total sample variance, suggesting that
most of the variation in the sample is related to
size. All eight of the dimensions are relatively
evenly weighted in PC1, with their eigenvectors
confined to the range 0.31–0.37. The largest of the
eigenvectors belong to the length dimensions, indi-
cating that larger astragali are slightly elongated in
the proximal-distal direction.
Size-independent variation in shape, if it
exists, is indicated by the second and third princi-
pal components (PC2 and PC3) (Mauk et al.,
1999). The Thousand Creek antilocaprid sample
indicates that the largest amount of size-indepen-
dent shape variation is driven by the increase of
the TD and the decrease of the medial length (LM),
lateral length (LL), and intermediate length (LI) of
the astragali (Table 3). TD was also the measure
most subject to repeatability problems, brought
about by preferential taphonomic wear of the astra-
gali, as explained in the section on Intra-Operator
Error. Overall, the second component of the analy-
sis contrasts shorter, thicker astragali with longer,
thinner astragali, without much change in width.
The third principal component is heavily positively
weighted by proximal thickness (TP) and heavily
negatively weighted by intermediate width (WI).
PC3 contrasts astragali with thick proximal ends
and thin centers against astragali with thin proximal
ends and thick centers.
Tests for Normality
Shapiro-Wilk tests (Shapiro and Wilk, 1956;
Zar, 1999) indicate that none of the Thousand
Creek measurements deviate significantly from
normal distributions except for distal width (WD:
p=0.0153, Table 1). A. americana deviates from
normality for LL, WD, and LI. These deviations in
A. americana are apparently driven by sexual
dimorphism, with female specimens smaller than
all male specimens. This degree of sexual dimor-
phism is typical of ruminants. The variance from
dimorphism should not impact the results because
all analyses are run at the species level with data-
sets that include both males and females. T. guy -
monensis does not deviate from normality for any
of its dimensions. Because there is no sign of
bimodality in the distribution of Thousand Creek
astragali, this part of the analysis cannot reject the
null hypothesis of a single biological species. Addi-
tionally, individual astragali cannot be assigned to
particular taxa based on their dimensions.
Coefficient of Variation (V*)
We find Ilingoceros and Sphenophalos to be
small antilocaprids with average body masses of
56.6 and 39.4 kg, respectively. Extant bovids of
similar body sizes include Aepyceros melampus,
Antidorcas marsupialis, Gazella granti, and Trage-
laphus scriptus (Nowak, 1999; Skinner and Smith-
ers, 1990). Antilocapra americana is also in the
same size range (around 50 kg; O’Gara, 1978). We
also compared the Thousand Creek fossils to
another fossil, Texoceros guymonensis. Tragela-
phus scriptus is the bovid with the largest coeffi-
cients of variation (among all small extant bovids
considered and for all variables); interestingly, it is
also the only forest-dwelling form of all of the ani-
mals, extinct and extant, included in our analysis.
There is no significant difference between the coef-
ficient of variation of Tr. scriptus (a single species)
and that of the Thousand Creek fossil assemblage
(Table 4). In a comparison between the Thousand
Creek assemblage and the species with the small-
est coefficients of variation (G. granti), two vari-
ables are not significantly different (LM and TP),
but G. granti is significantly lower for the other six
(Table 4). Comparison with the other two species is
TABLE 3. First three principal components of Thousand Creek antilocaprid astragali.
PC1 PC2 PC3
Size variation Size-independent variation in shape
Eigenvalue 6.5276 0.4219 0.3504
Percent 81.5945 5.2741 4.3795
Eigenvectors
LM 0.3651 -0.3738 0.0965
TD 0.3178 0.7765 -0.2646
TI 0.3590 0.2098 0.1506
TP 0.3284 0.2069 0.7848
LL 0.3764 -0.2173 0.0021
WD 0.3631 -0.1106 -0.2944
WI 0.3450 -0.0260 -0.4419
LI 0.3692 -0.3322 -0.0120

PALAEO-ELECTRONICA.ORG
9
split, with A. marsupialis showing no significant dif-
ferences, but A. melapus showing six values signif-
icantly lower than Thousand Creek (Table 4). The
test of differences between V* indicates that Thou-
sand Creek antilocaprids are significantly more
variable than A. americana in all dimensions and
are also more variable than T. guymonensis in five
of eight dimensions (Table 5, Figure 4). Addition-
ally, T. guymonensis is more variable than A. amer-
icana in five of eight dimensions.
DISCUSSION
Our multivariate analysis of antilocaprid astra-
gali from Thousand Creek cannot distinguish
among the three species diagnosed by horncores.
Consequently, either: (1) the analyzed astragali are
TAB L E 4 . Summary statistics of Bovid astragali.
Species mean sd V V* s.e. V* V* - 1kCr V* p
Aepyceros melapus LM 35.04 1.410 0.0402 0.0412 0.0103 -1.61 0.109
n=10 TD 16.53 1.036 0.0627 0.0642 0.0164 -1.49 0.138
TI 19.20 0.894 0.0466 0.0477 0.0120 -2.79 0.006
TP 13.76 0.660 0.0480 0.0492 0.0124 -2.94 0.004
LL 37.42 1.580 0.0422 0.0433 0.0109 -2.11 0.036
WD 21.78 0.900 0.0413 0.0424 0.0106 -3.75 0.000
WI 21.86 0.903 0.0413 0.0424 0.0106 -4.16 0.000
LI 28.94 1.195 0.0413 0.0423 0.0106 -2.15 0.032
Antidorcas marsupialis LM 28.16 1.637 0.0581 0.0599 0.0174 -0.09 0.930
n=8 TD 13.58 1.193 0.0879 0.0906 0.0269 0.04 0.967
TI 15.73 1.043 0.0663 0.0684 0.0199 -0.72 0.470
TP 11.16 0.938 0.0841 0.0867 0.0256 -0.04 0.966
LL 30.25 1.739 0.0575 0.0593 0.0172 -0.46 0.647
WD 18.79 1.132 0.0602 0.0621 0.0180 -1.26 0.209
WI 18.81 1.499 0.0797 0.0822 0.0242 -0.34 0.736
LI 23.66 1.349 0.0570 0.0588 0.0170 -0.43 0.669
Gazella granti LM 33.80 1.340 0.0396 0.0406 0.0102 -1.96 0.052
n=10 TD 17.04 0.837 0.0491 0.0503 0.0127 -2.91 0.004
TI 19.08 0.842 0.0441 0.0452 0.0114 -3.15 0.002
TP 13.33 0.943 0.0707 0.0725 0.0186 -0.80 0.424
LL 36.74 1.503 0.0409 0.0419 0.0105 -2.30 0.023
WD 21.95 0.920 0.0419 0.0430 0.0108 -3.65 0.000
WI 20.79 0.794 0.0382 0.0391 0.0098 -4.75 0.000
LI 28.65 1.154 0.0403 0.0413 0.0103 -2.30 0.022
Tragelaphus scriptus LM 33.6 2.729 0.08122 0.08291 0.01937 1.09 0.277
n=12 TD 15.23 1.495 0.09816 0.10021 0.02373 0.44 0.658
TI 18.03 1.597 0.08857 0.09042 0.02125 0.34 0.735
TP 13.41 1.25 0.09321 0.09516 0.02244 0.32 0.748
LL 35.73 3.106 0.08693 0.08874 0.02083 1.02 0.311
WD 21.23 1.903 0.08964 0.0915 0.02152 0.27 0.785
WI 19.59 1.987 0.10143 0.10354 0.02458 0.52 0.603
LI 28.96 2.539 0.08767 0.0895 0.02102 1.10 0.274

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
10
derived from only one of the species described
from horncores; (2) the horn core morphologies do
not reflect specific differences; or (3) the species
do not partition their resources in a way that is
reflected by their astragali. Possibility (1) is
extremely unlikely, because the sample size for
astragali (n=223) is an order of magnitude larger
than that for horncores (n=17). There are seven
Sphenophalos and 10 Ilingoceros horncores in the
curated Thousand Creek collections of the UCMP.
Assuming that the 136 astragali in the UCMP col-
lections were from only one of those taxa produces
a chi-square value of 95.2 (p<0.0001). Possibility
(2) is unlikely based on independent occurrences
of Sphenophalos without Ilingoceros. Assuming
that Furlong’s (1932) specimens of Sphenophalos
from deposits in Malheur County, Oregon, are a
random subsample of a population including both
forms (but recording only one) produces a chi-
square value of 7.143 (p<0.01) when compared to
the distribution of horncores from both forms in
Thousand Creek.
In addition, we can rule out possibilities 1 and
2 because our V* comparison indicates that the
Thousand Creek sample has greater variation than
that expected from a single species assemblage.
Clearly there is a great deal of variation in V* val-
ues between extant antelope species in the size
range of Ilingoceros and Sphenophalos, as seen in
the non-significance of a comparison between the
Thousand Creek sample and Tragelaphus scriptus;
however, because of the influence of evolutionary
history (see results of DFA), it is best to limit com-
parisons to the narrowest evolutionary distance
possible, in this case between the Thousand Creek
sample and T. guymonensis and A. americana.
Comparing the dispersion of variables in fossil spe-
cies with those of extant populations is a standard
procedure in paleontology; however, five measure-
ments of the known single-species fossil sample of
T. guymonensis are more variable than those of
the extant A. americana, suggesting caution when
interpreting the variance of fossil species. T. g uy-
monensis is approximately the same size as the
Thousand Creek antilocaprids and smaller than A.
TABLE 5. Comparison of V*, following Sokal and Braumann (1980).
Differences in coefficients of variation.
2 Standard Error of difference.
3 Degrees of freedom.
4 V*1-V*2 / S V*1-V*2.
V*1-V*2 1S V*1-V*2 2df 3t 4p
Thousand Creek
vs.
A. americana
LM 0.0249 0.0061 214 4.0560 <0.0001
TD 0.0277 0.0102 233 2.7131 0.0072
TI 0.0380 0.0077 239 4.9170 <0.0001
TP 0.0420 0.0078 236 5.3637 <0.0001
LL 0.0277 0.0067 221 4.1217 <0.0001
WD 0.0486 0.0069 217 7.0840 <0.0001
WI 0.0436 0.0081 225 5.3675 <0.0001
LI 0.0292 0.0063 238 4.6488 <0.0001
Thousand Creek
vs.
T. guymonensis
LM 0.0165 0.0051 255 3.2634 0.0013
TD 0.0057 0.0086 276 0.6687 n.s.
TI 0.0100 0.0076 281 1.3144 n.s.
TP 0.0183 0.0075 277 2.4535 0.0148
LL 0.0194 0.0054 263 3.5911 0.0004
WD 0.0262 0.0068 258 3.8444 0.0002
WI 0.0141 0.0082 264 1.7181 n.s.
LI 0.0118 0.0058 278 2.0317 0.0431
T. guymonensis
vs.
A. americana
LM 0.0083 0.0066 91 1.2725 n.s.
TD 0.0220 0.0118 89 1.8637 n.s.
TI 0.0280 0.0092 90 3.0462 0.0030
TP 0.0237 0.0089 91 2.6512 0.0095
LL 0.0083 0.0071 90 1.1573 n.s.
WD 0.0225 0.0074 91 3.0323 0.0032
WI 0.0295 0.0096 89 3.0813 0.0027
LI 0.0174 0.0073 88 2.4009 0.0185

PALAEO-ELECTRONICA.ORG
11
americana, so its high V* is not caused by a higher
body-mass. Additionally, T. guymonensis shows a
unimodal distribution, so it is not likely to be more
sexually dimporphic than A. americana. In this
case, the time-averaging of the Optima fossil
assemblage seems to have produced greater over-
all variance than averaging across the entire geo-
graphic range of extant A. americana;
consequently, the safest comparison is between
the unknown fossil assemblage (Thousand Creek)
and the known single-species fossil assemblage
(Optima). The Thousand Creek sample is signifi-
cantly higher than T. guymonensis, suggesting we
should reject the null hypothesis of one species.
Optima and Thousand Creek appear to have simi-
lar sampling regimes, in terms the quality of preser-
vation, but we cannot be sure they share similar
amounts of time averaging. We tentatively reject
the one-species hypothesis, but the influence of
time-averaging on V* indicates a final decision
must await a more complete analysis of the relative
amounts of time-averaging in the Thousand Creek
and Optima faunas.
This leaves a possibility (3) that the animals
were not sufficiently different in their astragalus
ecomorphology for discrimination because the spe-
cies had ecologies that did not dramatically differ in
a way reflected in their astragali. It is possible that
subtle differences not found in the PCA would be
uncovered with a DFA; however, the lack of a train-
ing set of known Ilingoceros and Sphenophalos
astragali means DFA cannot be used to analyze
our Thousand Creek dataset. Additionally, those
subtle differences are expected to be in shape and
should, therefore, be reflected in the PCA.
The normal distributions of the measurements
of the Thousand Creek and the Texoceros guy-
monensis samples contrast with the bimodal distri-
butions of the modern Antilocapra americana.
Antilocapra americana presents sexual dimor-
phism in both body size and horn morphology
(O’Gara, 1978), although the body size dimorphism
is not extreme. The normal distributions of the fos-
sil samples suggest three possibilities: 1) these
fossil taxa were not sexually dimorphic, at least for
body size, 2) they were dimorphic but enough time
is averaged in the sample to obscure it, or 3) for
Thousand Creek there are two dimorphic species
represented, with the males of the small species fit-
ting between the sexes of the larger species. We
cannot currently distinguish between these possi-
bilities. The lack of natural morphological breaks
among the Thousand Creek astragali means that
we cannot resolve the argument over whether Ilin-
FIGURE 4. Comparison of values of V* for the Thousand Creek antilocaprids, Texoceros guymonensis, and Antilo-
capra americana. Vertical bars represent 95% confidence intervals.

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
12
goceros schizoceras is merely a juvenile or female
form of I. alexandrae or a valid species. Final reso-
lution of this question awaits a morphometric anal-
ysis of the horncores of I. schizoceras and I.
alexandrae. This avenue of investigation should
examine whether the shape of the I. alexandrae
horn core could ontogenetically and allometrically
follow from that of I. schizoceras, expanding on the
work of Raup and Michelson (1965; Raup, 1966,
1967) with gastropod and cephalopod mollusk
shell coiling and Gould’s (1974) work on cervid ant-
ler growth.
In the absence of size or astragalar-shape
distinctions, how could Ilingoceros and Sphe-
nophalos coexist without the competitive exclusion
of one taxon? Apparent ecological overlap could
simply be a consequence of the coarseness of
astragalar shape as a proxy for morphological dif-
ferentiation, but the difference in horn core mor-
phologies of Ilingoceros and Sphenophalos
suggests that their species distinctions may have
been more social than ecological. The spiraling
horns of Ilingoceros, convergent on those of the
African bovid Tragelaphus, suggest a focus of the
attacks of aggressive males into wrestling
matches, reducing the likelihood of serious injury
from sparring (Geist, 1966; Lundrigan, 1996; Caro
et al., 2003). The shorter, forked horncores of
Sphenophalos, very similar to those of Antilocapra
(Furlong, 1932; Barbour and Schultz, 1941), are
associated with most confrontations leading to
withdrawal, because actual fights are violent and
lead to injury of one or both combatants (Geist,
1966; Lundrigan, 1996; Caro et al., 2003).
Although it appears that Ilingoceros and Sphe-
nophalos were very similar in size and aspects of
their ecology reflected in astragalar morphology,
male-male competition may have been different for
the two taxa.
The apparent inapplicability of the bovid habi-
tat discriminant function to A. americana suggests
that physical constraints on bovid and antilocaprid
astragalar functional morphology are overridden by
evolutionary history and consequent developmen-
tal constraints on astragalus morphology. The dis-
criminant function of DeGusta and Vrba (2003) is
apparently only characteristic of bovid antelope
and should not be directly applied to antilocaprids
or, potentially, any other family of artiodactyls,
because it will make erroneous predictions, colored
by the evolutionary history of bovids and African
antelopes. After considering these results, we
declined to test the refined discriminant function of
Weinand (2007) that also includes southeast Asian
bovids, because it would be subject to the same
historical constraints as that of DeGusta and Vrba
(2003).
CONCLUSION
There is more variance in the astragalus
dimensions of Thousand Creek antilocaprids than
expected in comparison to a sample of extant
Antilocapra americana or a similar fossil sample of
a single species, Texoceros guymonensis, but
there are not obvious breaks in the size distribution
that would permit diagnosis of individual species.
The normal, unimodal distribution of the Thousand
Creek sample likely reflects an overlap in size
between the largest individuals of the small-bodied
species and the smallest individuals of the large-
bodied species, or, potentially, size overlap among
three species, if Ilingoceros schizoceras is valid.
Statistical samples from two or more normally dis-
tributed populations may produce a single uni-
modal sample even if the population means are not
close together (Plavcan, 1993). The presence of
different source populations can then be inferred
only on the basis of the unusually high variance of
the sample (Simpson, 1947; Sokal and Braumann,
1980; Carrasco, 1998), as observed in the Thou-
sand Creek antilocaprids. Thus, recognition of
which astragali belong to which species is limited
to only the largest and smallest astragali—that is,
astragali that fall in the extreme upper and lower
~5% of the distribution, but little can be said with
confidence of the middle 90% (Appendix 1).
The results presented here indicate that
Sphenophalos and Ilingoceros were similar in body
size and astragalar shape, possibly indicating simi-
lar levels of agility and habitat preference for the
two genera. Differences in the horn morphologies
of the two genera probably reflect differences in
male-male competition. The two named species of
Ilingoceros, I. alexandrae, and I. schizoceras, may
represent different age classes or sexes of a single
species, but the data presented here cannot
resolve the issue. This taxonomic problem awaits
additional research into the growth of the Ilingoc-
eros horn.
In conclusion, we find promise in the use of
astragali to distinguish species of artiodactyls, but
that promise is tempered by the reality of biological
variation. Within the well-resolved modern African
antelope data of DeGusta and Vrba (2003), it was
possible to use astragalar measurements to distin-
guish species with a high level of success. If large
enough known samples from a family (e.g., bovids,
antilocaprids, cervids) can be used to train a DFA,

PALAEO-ELECTRONICA.ORG
13
astragali could be used to increase the sample
sizes of mammalian fossil assemblages that con-
tain members of that family. Care should be taken
in construction of the training sample, choosing
species that are likely to be in the time and region
of the unknown fossil sample. Obviously, this
method could not be used to identify new species;
it will only place samples into known species. Sam-
ples identified by DFA would, in turn, improve the
precision of paleoecological analyses based upon
relative abundances. Unfortunately, in cases like
that of Thousand Creek, where no training samples
are available, the similar sizes of closely related
species may preclude precise estimation of relative
abundances. Maximum likelihood analysis of mix-
ture models may help future attempts to use nor-
mally distributed measurements of postcranial
elements to differentiate species (Hunt and Chap-
man, 2001). The strong taxonomic signal recorded
in astragalar measurements also warns against
applying discriminant functions derived from one
broad taxonomic group to another: the habitat
based DFA from DeGusta and Vrba (2003) cannot
be expected to work with any other group than the
African bovids upon which it was based.
While we can tentatively reject the hypothesis
that there was only one species of antilocaprid at
Thousand Creek, we cannot improve on the rela-
tive abundances calculated from horncores. This
methodology will be most successful at extending
identifications from sites of known compositions
with cranial and postcranial remains to those with
few or no cranial remains.
ACKNOWLEDGMENTS
We thank P. Holroyd (UCMP), C. Conroy
(MVZ), S. McLeod (LACM), S. Bell (AMNH), B.
Evander (AMNH), and the late R. Tedford (AMNH)
for access to specimens and helpful advice. We
thank S. Hopkins, B. Feranec, D. Prothero, D.
Erwin, T. Barnosky, M. Carrasco, the rest of the
Barnosky Lab as well as J. Orcutt for helpful criti-
cism in the process of this research. Without the
help of B. Day, N. Valentine, and others in the US
FWS, EBD would not have been able collect fossil
astragali in the Thousand Creek Beds of the Shel-
don NWR. We would like to thank C. Janis and
three anonymous reviewers for their constructive
reviews of our manuscript. EBD would especially
like to thank C. Hickman, B. Clemens, D. Sloan,
and the rest of the board of The George D. Louder-
back Fund, Inc., for financing his calipers and por-
tions of his trips to LACM and AMNH. This
research began while EBD was a Graduate
Research Fellow of the NSF. Additionally, the Geo-
logical Society of America provided grant money
that helped finance EBD’s trip to the AMNH. Part of
this research was undertaken while JC was sup-
ported by an Explo’ra sup scholarship (Université
Claude Bernard Lyon I).
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16
APPENDIX 1
List of included UCMP and LACM specimens from Thousand Creek, Nevada.
Abbreviations: #, number; R, right; L, left; I., Ilingoceros; S., Sphenophalos; LM, medial
length; TD, distal thickness; TI, intermediate thickness; TP, proximal thickness; LL, lat-
eral length; WD, distal width; WI, intermediate width; LI, intermediate length.
Museum Loc. # Specimen
#Side Taxon LM TD TI TP LL WD WI LI
LACM 3746 89840 L I. or S. 27.2 14.15 15.8 10.5 31.35 18.3 17.8 22.9
LACM 3747 90213 R I. or S. 25.9 12.85 14.3 10.35 — 17.55 16.2 21.95
LACM 3747 90214 R I. or S. 28.3 14.9 14.6 10.8 30.5 18 17.25 24.15
LACM 5813 150577 R I. or S. 29.3 13.9 15.5 11.3 31.9 18.2 17.4 24.8
LACM 5813 150580 L I. or S. 29 11.6 14.3 — — — 17.1 25.75
LACM (CIT) 63 98343 R I. or S. 28.05 12.95 15.5 10.95 29.9 19.2 18.7 23.6
LACM (CIT) 63 98344 R I. or S. — 14.75 14.9 10.7 28.6 — 16 22.9
LACM (CIT) 63 98345 R I. or S. 29.2 15.65 16.65 12.1 32.2 19.95 18.5 25.35
LACM (CIT) 63 98346 R I. or S. 30 15.5 17.3 12.15 32.6 20.6 18.6 25.9
LACM (CIT) 63 98347 R I. or S. 29.7 14.5 15.9 12.05 32.55 20.6 19.9 25.65
LACM (CIT) 63 98348 R I. or S. 27.2 13.65 15.05 11.35 29.6 18.75 16.6 23.25
LACM (CIT) 63 98349 R I. or S. 29.65 14.5 16.2 11.35 31.75 18.7 — 25.4
LACM (CIT) 63 98350 R I. or S. 28.4 14.75 16.5 10.85 — 19.7 20.05 —
LACM (CIT) 63 98351 R I. or S. 28.35 14.3 16.15 11.9 31.65 18.7 17.55 24.15
LACM (CIT) 63 98352 R I. or S. 26.35 13.7 15.35 10.65 28.6 17.95 16.7 22.2
LACM (CIT) 63 98353 R I. or S. 26.7 13.3 14.7 10.75 29.6 17.6 16.85 22.8
LACM (CIT) 63 98354 R I. or S. — 14.5 16.4 12.1 32.9 — — 26
LACM (CIT) 63 98355 R I. or S. 28.3 13.8 15.3 11.05 31.05 19.5 17.15 24.9
LACM (CIT) 63 98356 R I. or S. 29.55 14.2 16.2 12 31.8 19.9 18 25.2
LACM (CIT) 63 98357 R I. or S. — 14.7 16 12.5 32.1 — — 25.1
LACM (CIT) 63 98358 R I. or S. — 12.6 14.2 9.8 — 17.35 16.25 22.7
LACM (CIT) 63 98359 R I. or S. 27.95 15.4 15.6 11.1 30.4 18.7 17.3 24.1
LACM (CIT) 63 98360 R I. or S. 29.2 15.2 16.5 11.2 33 21 18.9 25.6
LACM (CIT) 63 98361 R I. or S. 28.2 13.85 14.7 10.3 30.45 18.9 16.35 24.3
LACM (CIT) 63 98362 R I. or S. 31.5 15.15 16.2 11.35 35.35 20.75 19.4 28.2
LACM (CIT) 63 98363 R I. or S. 25 11.9 13.15 9.75 27.75 16 15.35 21.5
LACM (CIT) 63 98364 R I. or S. 28.6 14.3 16.25 11.75 31.7 19.55 18.6 24.95
LACM (CIT) 63 98365 R I. or S. 26.4 14 14.8 8.9 29.65 18.3 18.5 23.6
LACM (CIT) 63 98366 R I. or S. 28.9 15.3 17.4 12.7 32.35 21.6 19.7 24.55
LACM (CIT) 63 98367 R S. 33.5 16.55 18.6 13 36.6 21.85 22.3 29
LACM (CIT) 63 98368 R I. or S. 27.1 13.5 15.15 9.3 — 18.9 17.25 32.85
LACM (CIT) 63 98369 R I. or S. 27.9 14.8 15.1 11.3 31.4 18.9 17.9 24
LACM (CIT) 63 98370 R I. or S. 26.55 12.1 13.85 10.2 28.45 16.4 14.85 22.15
LACM (CIT) 63 98371 R I. or S. 28.15 14.6 15.5 11.25 30.85 19.65 17.05 24.7
LACM (CIT) 63 98372 R I. or S. — 13.25 15.7 11.15 31.65 18.9 16.65 24.65
LACM (CIT) 63 98373 R I. or S. 29 13.75 15.3 11.1 31.4 19 18 24.45

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LACM (CIT) 63 98374 R I. or S. 28.7 12.95 14.3 11.5 29.95 19.6 19.3 23.7
LACM (CIT) 63 98375 R I. or S. 27.7 13.55 15.35 11.2 30.45 18.8 18.05 24.5
LACM (CIT) 63 98376 R S. 30.75 16.3 18.05 13.15 33.75 21.7 20.45 27
LACM (CIT) 63 98377 R I. or S. — 13.85 15.3 10.9 31.2 19.5 18.7 24.25
LACM (CIT) 63 98378 R I. or S. — 13.9 14.4 10.75 30.5 — 16.7 23.8
LACM (CIT) 63 98379 R I. or S. 25.1 12.75 13.35 9.6 27.1 16.2 16 21.1
LACM (CIT) 63 98380 R I. or S. 27.5 14 15.7 11.8 31.15 18.5 19.4 23.3
LACM (CIT) 63 98381 R I. or S. 28.2 14.45 14.1 9.9 30.4 17.5 15.7 24.45
LACM (CIT) 63 98382 R I. or S. 25 15.85 13.1 9.55 27.3 17.45 16.7 21.5
LACM (CIT) 63 98383 R I. or S. 28.5 14.9 16.2 11 30.9 19.25 19.5 24.4
LACM (CIT) 63 98384 R I. or S. 27.9 14.45 18.75 11.1 30.75 19.05 19.05 24
LACM (CIT) 63 98385 R I. or S. 27.75 13.6 15.7 11.35 31.05 18.8 17.2 23.95
LACM (CIT) 63 98386 R I. or S. 27.95 14.45 15.1 10.9 29.9 18.25 16.8 23.5
LACM (CIT) 63 98387 R I. or S. 29.1 13.4 15.35 10.8 31.8 19.2 18.2 24.7
LACM (CIT) 63 98402 L I. or S. 29.3 13.95 15.45 11.75 32.45 20.35 19.9 25.5
LACM (CIT) 63 98403 L I. or S. 29.05 14.75 16.2 12.55 32.85 19.9 19.3 25.6
LACM (CIT) 63 98404 L I. 23.4 12.45 12.25 9.6 25.2 14.7 14.1 19.55
LACM (CIT) 63 98405 L I. or S. 25.9 13.15 14.2 10.15 29.15 18.6 17.95 22.95
LACM (CIT) 63 98405 L I. or S. — 11.9 15.5 11.25 31.4 18.4 17.2 —
LACM (CIT) 63 98407 L I. or S. 26.55 11.9 14.15 — — 17.2 17.15 —
LACM (CIT) 63 98408 L I. or S. 29.2 14.1 16.4 — — 18.7 — 25.05
LACM (CIT) 63 98409 L I. or S. 27.9 13.4 15.45 10.95 29.75 18.9 18 23.3
LACM (CIT) 63 98410 L I. or S. 26.85 14.3 14.6 11.3 29.1 18 17.55 23.35
LACM (CIT) 63 98411 L I. or S. 27.5 — — 9.65 30 18.25 17 23.7
LACM (CIT) 63 98412 L I. or S. 26.2 12.85 16.9 11.3 30.1 18.5 16.85 22.3
LACM (CIT) 63 98413 L I. or S. 27.3 12.85 15.55 10.85 28.4 18.35 15.45 23.4
LACM (CIT) 63 98414 L I. or S. 29.5 — — 11.1 — — 18 24.9
LACM (CIT) 63 98415 L I. or S. 30.7 14.25 16.85 11.45 33.25 20 18.45 26.05
LACM (CIT) 63 98416 L I. 24.5 10.45 12.05 7.8 — 13.7 13.7 21.4
LACM (CIT) 63 98417 L I. or S. 28.05 14.8 15.35 11.7 30.2 18.6 17.4 23.65
LACM (CIT) 63 98418 L I. or S. 28.75 13.3 15 11.4 29.9 18 16.8 23.4
LACM (CIT) 63 98419 L I. or S. 25 12.55 14 10.1 17.4 17.35 16.35 21.5
LACM (CIT) 63 98420 L I. or S. 28.1 13.3 14.9 10.6 30.45 19.05 18.3 24
LACM (CIT) 63 98421 L I. or S. 26.65 13.6 14.4 11.5 29.25 17.9 17.25 32.15
LACM (CIT) 63 98422 L I. or S. 28.1 15.8 16.15 11.85 31.6 — 18.6 24.65
LACM (CIT) 63 98423 L I. or S. 25.8 13.75 13.35 9.25 28.85 16.9 15.85 22.15
LACM (CIT) 63 98424 L I. or S. 28.2 14.3 16.15 11.4 30.7 19.25 17.9 24.05
LACM (CIT) 63 98425 L I. or S. 26.35 13.15 13.9 9.8 27.7 17.4 17.85 22.3
LACM (CIT) 63 98426 L I. or S. 26.25 14.3 15.35 10.65 — 17.65 16.1 21.45
LACM (CIT) 63 98427 L I. or S. 28.5 13.6 14.65 12 30.8 18.1 16.9 24
LACM (CIT) 63 98428 L I. or S. 29.1 — 16.55 11.6 31.9 20 17.75 24.7
Museum Loc. # Specimen
#Side Taxon LM TD TI TP LL WD WI LI

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
18
LACM (CIT) 63 98429 L I. or S. 26.1 13.7 13.95 10.7 28.7 17.9 18.2 22.95
LACM (CIT) 63 98430 L I. or S. — 13.9 15.6 3.3 — 13 16.2 23.4
LACM (CIT) 63 98431 L I. or S. 28.1 12.9 14.45 11.8 30.5 18.1 17.3 23.7
LACM (CIT) 63 98432 L I. or S. 30.8 15.7 16.45 — — 20.4 19 —
LACM (CIT) 63 98433 L I. or S. 28.2 15.45 17.1 11.5 31.7 19.4 18.7 24.5
LACM (CIT) 63 98434 L I. or S. 27.75 14.85 15.5 11.5 31.3 19.2 18.4 24.3
LACM (CIT) 63 98435 L I. or S. 27.1 12.25 14.1 9.7 30.5 18.1 16.9 23.1
LACM (CIT) 63 98436 L I. or S. 26.7 12.7 15 11.75 — 18.55 18.1 22.95
LACM (CIT) 63 98437 L I. or S. 27.8 13.6 16.1 11.2 30.2 18.3 17.55 23.4
LACM (CIT) 63 98438 L I. or S. 26.5 13.2 14.3 11.1 29.5 17.4 17.65 22.4
UCMP 1097 164808 L I. or S. 28 13.3 15.65 12.96 31.74 18.89 18.07 24.37
UCMP 1097 164809 R I. or S. 26.95 15.65 15.79 11.2 30.57 20.13 18.51 23.87
UCMP 1100 70318 R I. or S. 26.75 13.58 14.66 11.17 28.78 18.04 17.41 22.5
UCMP 1100 153940 R I. or S. 26.59 13.56 15.81 10.67 29.03 17.92 17.75 22.82
UCMP 1100 153941 R I. or S. 27.07 12.33 13.93 9.78 29.28 17.38 16.68 23.09
UCMP 1100 153942 R I. or S. 27.47 13.78 15.43 10.67 31.12 18.48 16.03 23.77
UCMP 1100 153943 R I. or S. 26.71 14.16 15.18 11.01 29.08 18.37 17.13 23.48
UCMP 1100 153944 R I. or S. — 13.08 14.78 11.11 — — — 23.49
UCMP 1100 153945 R S. 30.57 15.08 16.9 11.8 34.16 21.41 20.7 26.94
UCMP 1100 153946 R I. or S. 28.4 12.85 14.62 11.33 30.7 18.77 17.6 24.12
UCMP 1100 153947 R I. or S. — 14.82 15.08 12.13 31.57 — — 24.82
UCMP 1100 153948 R I. or S. 29.02 12.82 15.67 11.66 30.75 19.54 17.93 24.57
UCMP 1100 153949 R I. or S. 27.66 15.58 15.77 10.33 30.24 18.21 17.72 23.46
UCMP 1100 153950 R I. or S. 28.32 14.76 16.06 11.7 30.55 19.69 19.11 24.85
UCMP 1100 153951 R I. or S. 26.47 13.35 14.47 11.08 29.02 18.41 16.02 23.12
UCMP 1100 153952 R I. or S. 25.55 13.14 14.75 10.15 27.37 17.25 15.91 21.75
UCMP 1100 153953 R I. or S. — 14.59 14.88 11.23 29.99 — 18.77 23.47
UCMP 1100 153954 R I. or S. 26.12 12.2 14.62 10.4 28.34 17.66 16.55 22.56
UCMP 1100 153955 R I. or S. 28.47 14.8 15.75 11.69 31.63 19.49 18.75 24.98
UCMP 1100 153956 R I. or S. — 14.32 16.15 11.41 30.59 — — 23.81
UCMP 1100 153957 R I. or S. 26.18 11.93 14 10.92 28.12 17.28 16.04 21.99
UCMP 1100 153958 R I. or S. 29.3 17.12 15.8 12.16 — — 18.11 25.53
UCMP 1100 153959 R I. or S. 27.16 13.25 14.74 10.05 29.09 17.43 16.98 23.18
UCMP 1100 153960 R I. or S. 28.97 16.24 17.4 12.14 33.33 20.63 20.07 25.42
UCMP 1100 153961 R I. or S. 29.75 15.63 17.72 11.87 32.94 20.33 19.51 25.73
UCMP 1100 153962 R I. or S. — — 14.99 10.78 — — 16.92 24.98
UCMP 1100 153963 R I. or S. 30.14 16.45 17.55 12.32 33.21 21.31 19.31 26.09
UCMP 1100 153964 R I. or S. 30.14 18.15 17.65 12.7 33.61 21.26 20.86 26.48
UCMP 1100 153965 R I. or S. 29.64 15.24 16.7 11.74 31.7 21.35 19.95 25.53
UCMP 1100 153966 R I. or S. 26.48 13.36 14.57 10.04 28.73 17.75 16.07 22.54
UCMP 1100 153967 R I. or S. 26.12 12.35 13.89 9.57 28.27 15.96 14.93 22.81
Museum Loc. # Specimen
#Side Taxon LM TD TI TP LL WD WI LI

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UCMP 1100 153968 R I. or S. — 15.25 16.73 12.86 33.58 19.71 18.13 25.61
UCMP 1100 153969 R I. or S. 26.38 13.63 15.04 10.69 28.98 18.82 17.82 22.92
UCMP 1100 153970 R I. or S. 25.3 13.27 14.36 9.99 27.3 16.99 16.55 21.6
UCMP 1100 153971 R S. 30.86 16.13 18.07 12.72 34.91 22.21 18.99 26.97
UCMP 1100 153972 R S. 30.19 17.89 18.91 13.23 34.71 23.28 22.4 27.06
UCMP 1100 153973 R I. or S. 27.52 14.11 15.23 — — 18.75 17.51 —
UCMP 1100 153974 R I. or S. — 14.13 15.86 10.63 28.95 — — 22.83
UCMP 1100 153975 L I. or S. 28.89 14.83 16.68 12.88 31.59 19.44 19.17 25.38
UCMP 1100 153976 L I. or S. 26.44 14.16 15.6 11.77 29.26 17.92 19.07 22.78
UCMP 1100 153977 L I. or S. 27.16 13.55 15.58 10.61 30.02 18.75 18.05 23.63
UCMP 1100 153978 L I. or S. 25.67 13.49 15.04 10.52 28.14 18.47 16.55 22.34
UCMP 1100 153979 L I. or S. 28.99 14.09 15.57 10.72 31.87 19.28 17.87 25.14
UCMP 1100 153980 L I. or S. 25.58 13.42 14.37 10.64 27.94 17.82 16.99 21.93
UCMP 1100 153981 L I. or S. 27.21 13.62 13.03 9.93 29.8 17.59 — 23.72
UCMP 1100 153982 L I. or S. 28.28 14.69 16.07 11.42 31.21 19.63 18.83 24.1
UCMP 1100 153983 L I. or S. 27.84 13.17 15.26 10.67 31.14 18.9 18.4 24.46
UCMP 1100 153984 L I. or S. 27.87 14.23 15.53 10.78 30.6 19.36 19.56 24.66
UCMP 1100 153985 L I. or S. 27.68 13.33 13.31 11.15 30.17 18.01 17.46 23.67
UCMP 1100 153986 L I. or S. 28.17 13.9 14.42 10.16 29.05 18.72 16.33 24.05
UCMP 1100 153987 L I. or S. 28.08 14.21 15.93 11.75 30.99 19.16 18.1 24.04
UCMP 1100 153988 L I. or S. 28.14 14.35 15.87 11.5 30.25 18.73 18.22 24.55
UCMP 1100 153989 L I. or S. 30.32 16.34 16.61 11.84 33.47 20.35 19.39 25.92
UCMP 1100 153990 L I. or S. 27.23 14.83 15.46 11.95 30.51 19.52 18.73 23.54
UCMP 1100 153991 L I. or S. 25.75 12.57 14.45 10.23 27.96 16.96 16.72 22.06
UCMP 1100 153992 L I. 22.18 8.26 10.33 9.24 22.76 15.34 14.62 19.5
UCMP 1100 153993 L I. or S. 27.64 14.82 15.78 11.47 30.96 19.7 17.96 24.14
UCMP 1100 153994 L I. or S. 26.81 13.7 14.6 11.51 29.3 18.27 16.91 23.2
UCMP 1100 153995 L I. or S. 25.6 12.71 14.39 10.26 27.44 16.86 15.8 21.46
UCMP 1100 153996 L I. or S. 27.99 14.34 15.75 11.79 30.56 19.35 18.81 24.5
UCMP 1100 153997 L I. or S. 25.85 12.44 13.13 9.95 27.44 17.06 15.65 22.12
UCMP 1100 153998 L I. or S. — 17.21 17.14 13.02 31.37 — — —
UCMP V6570 35624 L I. or S. 26.15 13.63 15.03 11.16 28.84 18.39 17.37 22.85
UCMP V6570 164814 L I. or S. 27.96 13.46 13.81 9.27 30.88 19.7 18.22 24.65
UCMP V6570 164815 L I. or S. 30.49 15.56 15.62 12.89 32.63 21.06 20.22 26.15
UCMP V6570 164816 L I. or S. 29.43 15.97 17.47 12.67 32.3 20.41 19.27 25.29
UCMP V6570 164817 L I. or S. 28.87 15.33 15.94 11.09 31.07 19.23 18.87 24.82
UCMP V6570 164818 L I. or S. 27.24 13.88 15.31 10.93 29.71 19.1 18.02 23.76
UCMP V6570 164819 L I. or S. 24.29 13.02 13.5 10.44 27.03 17.56 17.02 20.99
UCMP V6570 164820 R I. or S. 28.71 14.46 15.34 10.98 30.98 19.41 18.66 24.69
UCMP V6570 164821 R I. or S. 25.84 13.87 15.93 11.16 — 18.25 18.46 23.65
UCMP V6570 164822 R I. or S. 30.48 15.74 17.77 11.48 33.18 20.97 19.73 23.87
Museum Loc. # Specimen
#Side Taxon LM TD TI TP LL WD WI LI

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
20
UCMP V6570 164823 R I. or S. 29.12 13.47 14.69 11.73 28.91 16.24 15.91 25.22
UCMP V6570 164824 R I. or S. 27.41 14.17 14.82 11.46 30.27 18.88 17.3 24.81
UCMP V6570 164825 R I. or S. 28.41 14.25 16.83 11.16 30.82 19.27 18.15 23.89
UCMP V6570 164826 R I. or S. 28.7 14.77 15.63 11.1 31.28 18.88 17.99 24.8
UCMP V6570 164827 R I. or S. 29.32 14.89 15.92 11.52 32.53 21.82 20.86 25.85
UCMP V6570 164828 R I. or S. 27.39 13.09 14.25 10.78 29.97 18.49 15.84 23.27
UCMP V6570 164829 R I. or S. 29.86 13.67 16.89 11.57 31.92 18.73 18.92 25.35
UCMP V78061 164810 R I. or S. 26.81 — 14.65 10.87 29.95 16.83 — 22.24
UCMP V78061 164811 R I. or S. — 12.89 14.38 10.42 29.19 — 15.33 23.34
UCMP V78061 164812 R I. or S. 28.5 14.19 15.26 9.86 30.97 17.64 17.59 23.81
UCMP V78062 164813 L I. or S. 25.01 13.8 13.94 10.89 26.75 16.09 15.19 20.71
UCMP V78065 164751 L I. or S. 29.72 15.75 16.87 12.38 33.74 18.37 18.72 25.52
UCMP V78065 164752 R I. 24.92 10.92 12.99 — 27.86 15.06 14.32 22.07
UCMP V78069 164760 R I. or S. 26.32 13.38 15.37 11.15 30.16 19.02 — 23.36
UCMP V78069 164761 L I. or S. — 11.69 13.28 9.54 27.42 16.29 14.15 22.58
UCMP V78069 164762 R I. or S. 27.23 14.59 15.07 9.12 29.95 18.77 16.98 23.21
UCMP V91087 164757 R I. or S. 27.76 14.44 15.09 11.19 30.2 19.27 18.15 23.3
UCMP V91087 164758 L I. or S. 26.58 13.55 14.88 10.69 28.54 18.52 17.36 22.56
UCMP V91087 164759 R I. or S. — — — 12.39 — — 18.83 —
UCMP V91089 164747 L I. 23.12 11.93 11.75 9.17 25.03 13.01 13.87 19.55
UCMP V91089 164748 L I. or S. 25.32 14.05 13.5 11.03 27.97 17.1 17.05 22.18
UCMP V91089 164749 L I. or S. 28.49——————24.03
UCMP V91089 164750 R I. or S. 27.69 13.88 15.33 10.21 29.01 17.3 15.82 23.52
UCMP V91089 164763 L I. or S. 28.28 14.59 16.32 12.11 32.12 18.44 16.61 24.49
UCMP V91089 164764 R I. or S. 30.13 15.39 16.6 12.27 32.95 21.18 19.13 26.09
UCMP V91089 164765 R I. or S. 25.66 12.84 13.66 9.65 27.56 16 14.89 21.81
UCMP V91095 164775 R I. or S. 30.4 15.92 17.53 13.8 33.67 19.85 18.56 26.37
UCMP V91095 164776 L I. or S. 27.9 14.1 15.16 11.04 30.13 19.45 19.84 23.76
UCMP V91095 164793 L I. or S. 26.92 12.91 14.33 11.23 29.8 18.34 17.18 22.95
UCMP V91095 164794 R I. or S. 27.85 15.89 16.51 12.11 30.64 19.41 20.12 24.23
UCMP V91095 164795 R I. or S. 26.85 15.32 15.28 10.1 29.73 19.06 17.61 23.25
UCMP V91095 164796 R I. or S. 25.87 14.67 14.6 10.82 29.41 18.75 18.13 22.47
UCMP V91096 164787 L I. or S. 28.49 13.62 15.17 11.4 30.52 18.88 19.22 24.23
UCMP V91096 164788 L I. or S. 27.37 13.5 15.21 11.37 30.55 17.95 16.06 22.8
UCMP V91096 164797 L I. or S. 28.37 15.45 15.61 11.96 30.07 18.43 17.57 23.94
UCMP V91097 153999 R I. or S. 30.36 13.58 16.31 12.06 33.7 21.26 21.52 26.1
UCMP V91097 164767 R I. or S. 30.3——————26.04
UCMP V91097 164768 L S. 31.96 15.29 18 12.49 36.13 22.11 21.1 27.58
UCMP V91097 164769 L I. or S. 29.18 15.2 16.01 11.95 31.54 19.56 19.61 25.76
UCMP V91097 164770 R I. or S. — 16.49 16.21 11.6 32.42 19.7 17.55 26.6
UCMP V91097 164777 R I. or S. 30.45——————26.78
Museum Loc. # Specimen
#Side Taxon LM TD TI TP LL WD WI LI

PALAEO-ELECTRONICA.ORG
21
UCMP V91097 164778 L I. or S. 29.8 16.33 16.81 11.91 32.9 19.66 20.06 25.19
UCMP V91097 164779 L I. or S. 29.25 15.96 17.13 12.28 32.12 20.2 19.07 25.23
UCMP V91097 164780 L I. or S. 28.08 15.5 15.74 11.73 30.88 18.76 19.36 23.95
UCMP V91097 164782 R I. or S. 29.84 14.6 16.13 10.39 — 19.37 17.07 24.62
UCMP V91097 164783 R I. or S. 28.84 13.37 14.97 10.96 30.28 19.85 19.02 24.95
UCMP V91097 164784 R I. or S. 30.46 16.99 17.11 — — 20.4 19.81 26.56
UCMP V91097 164785 R I. or S. — 13.9 14.8 10.11 29.26 17.91 16.34 22.75
UCMP V91097 164790 L I. or S. 27.1 13.42 15.1 11.25 29.26 17.24 16.92 23.3
UCMP V91097 164791 L S. 30.43 16.86 17.71 13.67 34.79 21.56 20.56 26.48
UCMP V91097 164792 R I. or S. — 15.65 16.29 12.21 34.7 — 18.22 26.84
UCMP V91097 164799 R I. or S. — 14.56 14.6 10.35 28.85 — — 22.98
UCMP V91097 164800 L I. or S. — 15.75 16.07 11.1 30.67 — 16.02 —
UCMP V91097 164801 L I. or S. 28.36 15.26 16.05 11.16 31.91 19.88 20.16 24.94
UCMP V91097 164804 R I. or S. 28.66 14.38 14.92 11.84 32.16 — 17.77 24.46
UCMP V91097 164806 R I. or S. 28.05 15 15.28 10.73 31.49 17.74 18.14 23.63
UCMP V91097 164807 L I. or S. — 14.76 16.13 11.26 32.41 — 17.67 24.99
UCMP V99408 158341 R I. or S. 28.94 15.35 15.9 11.98 32.74 19.91 17.71 25.13
UCMP V99412 158394 R I. or S. — 13.86 13.74 9.69 — 15.96 13.34 20.62
UCMP V99414 157152 R I. 24.87 12.83 12.6 8.16 26.05 14.95 14.06 21.04
UCMP V99414 157171 L I. or S. — 13.23 13.82 10.2 27.5 — — 21.19
UCMP V99416 157221 L I. or S. — 15.51 17.32 11.74 33.93 — — 25.6
UCMP V99443 157243 R I. or S. 29.13 15.21 16.57 11.89 31.78 18.94 17.25 25.16
UCMP V99443 157249 L I. or S. — 13.48 13.98 9.91 29.78 — — —
Museum Loc. # Specimen
#Side Taxon LM TD TI TP LL WD WI LI

DAVIS AND CALÈDE: ARTIODACTYL ASTRAGALI
22
APPENDIX 2
Results of the discriminant function analysis on the set of measurements of Antilo-
capra americana. Abbreviations: M, male; F, female; R, right; L, left. All specimens are
from the museum of Vertebrate Zoology (MVZ).
Specimen
number M/F Side Predicted Body Mass
(Kg)
Predicted
Habitat
Forest
%
Heavy cover
%
Light cover
%
Open
%
8299 M R 55.496 O 0.004 0.035 0.267 0.694
8299 M L 40.981 F 0.557 0.022 0.148 0.273
19231 M R 40.530 O 0.176 0.034 0.192 0.599
19231 M L n.a. H 0.000 1.000 0.000 0.000
31157 F R n.a. n.a. n.a. n.a. n.a. n.a.
31157 F L 54.255 L 0.037 0.065 0.578 0.320
38313 ? R 56.090 L 0.031 0.090 0.551 0.328
38313 ? L 53.177 L 0.122 0.195 0.493 0.190
40146 ? R 54.760 L 0.084 0.237 0.531 0.149
40146 ? L 47.778 L 0.053 0.047 0.635 0.265
40147 ? R 49.618 L 0.016 0.101 0.470 0.413
40147 ? L 44.384 L 0.048 0.049 0.729 0.175
44387 M R 44.858 L 0.083 0.035 0.742 0.141
44387 M L 56.509 O 0.012 0.043 0.341 0.604
78223 M R 57.305 O 0.051 0.025 0.236 0.687
78223 M L 56.014 L 0.018 0.126 0.691 0.166
88135 F L 57.515 L 0.028 0.072 0.637 0.264
98090 M R 53.817 L 0.066 0.098 0.587 0.249
98090 M L 55.764 L 0.029 0.045 0.745 0.181
181287 ? R 59.372 O 0.029 0.049 0.295 0.627
184200 F R 61.397 O 0.022 0.033 0.249 0.697
184200 F L 56.011 L 0.036 0.185 0.492 0.287
184202 ? R 55.838 O 0.028 0.235 0.347 0.391
184202 ? L 41.912 L 0.081 0.092 0.675 0.151
186277 F R 58.141 L 0.011 0.052 0.495 0.442
186277 F L 56.248 O 0.024 0.035 0.424 0.518