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264
Jayaraj et al. – A Model to Differentiate Cynopterus brachyotis Forms
on Wilks’ lambda (Table 3), and 6 characters
(GBPL, M3L, M3W, TVL, D3P2L, and RL; Table
4) were generated from the stepwise procedure.
The characters with the highest weight on function
1 were RL (0.957) and M3L (0.506), whereas
M3L (3.912) and M3W (-3.454) had the highest
discriminant loadings. All 6 characters determined
by the stepwise procedure produced a discriminant
function with an accuracy rate of 100% (see
accuracy rates, Table 5).
For analysis of only external morphological
characters, the stepwise method identified a
discriminant function (Function 1) that was statistically
significant (Table 6) with 4 characters (TVL,
D3P1L, D3MCL, and RL; Table 7) generated from
the stepwise procedure. The character with the
highest weight and loading was RL (weight = 1.240;
loading = 0.706), while D3MCL (-0.731) had the
2nd-highest weight. All 4 characters determined
by the stepwise procedure produced a discriminant
function with an accuracy rate of 96.8% (see
accuracy rates, Table 8).
A histogram of the discriminant scores
of the discriminant function for all characters
Table 1. Sexual dimorphism test using a t-test for equality of means (equal/unequal variances; only sexually
dimorphic characters are shown)
C. horsfieldii C. brachyotis
Character IOW D3MCL D5MCL
t 3.434 1.346 1.113
d.f. 8 32 32
Significance (2-tailed *) 0.009 0.021 0.090
Conclusion sexually dimorphic sexually dimorphic sexually dimorphic
Characters are defined in “MATERIALS AND METHODS”.
Table 2. Means and standard deviations (SDs) of all characters used in this analysis
Cynopterus cf. brachyotis Forest C. brachyotis Overall
Character Mean S.D. Mean S.D. Mean S.D.
GSL 27.39 0.76 28.45 0.88 27.92 0.97
IOW 5.60 0.32 5.92 0.36 5.76 0.37
POW 6.32 0.60 6.48 0.65 6.40 0.63
CW 12.06 0.39 12.39 0.36 12.23 0.41
MW 12.23 0.40 12.66 0.43 12.45 0.47
ZW 17.93 0.79 18.40 0.80 18.16 0.82
DBC 5.62 1.07 4.72 0.79 5.17 1.04
BL 2.60 0.58 2.18 0.42 2.39 0.55
GBPL 6.95 0.93 5.72 0.90 6.34 1.10
C1BW 1.61 0.24 1.44 0.20 1.52 0.24
C1C1B 5.92 0.29 6.05 0.30 5.99 0.30
M3M3B 8.37 0.36 8.44 0.36 8.40 0.36
C1M3L 8.94 0.39 9.10 0.28 9.02 0.34
M3L 1.83 0.11 1.95 0.14 1.89 0.14
M3W 1.25 0.15 1.18 0.13 1.21 0.14
TVL 11.40 1.95 11.47 2.63 11.43 2.29
EL 14.48 1.34 14.67 1.29 14.58 1.31
D3P1L 26.63 1.37 28.38 1.25 27.51 1.57
D3P2L 33.75 2.32 36.19 2.42 34.97 2.65
D3MCL 41.47 1.76 43.06 1.71 42.27 1.90
D4MCL 38.87 1.40 40.94 1.63 39.91 1.83
D5MCL 39.64 1.43 42.31 1.44 40.98 1.96
RL 58.08 1.40 63.55 2.04 60.82 3.26
LogPES 1.02 0.04 1.04 0.07 1.03 0.06
Characters are defined in “MATERIALS AND METHODS”.