SEXUAL DIMORPHISM IN THE LACERTID

. Apathya cappadocica is a medium-sized lizard species included in the family Lacertidae. The species is known from Türkiye, Northern Syria, Iraq, and Western Iran. Sexual dimorphism (SD), which is a phenomenon including phenotypic differences between males and females, has many effects on behaviour, shape and size characteristics. A total of 87 adult lizard specimens collected from south-eastern Anatolia were used in this study. The results of ANOVA showed that all morphometric features exhibited a pattern in which males have larger size than females. According to principal component analysis (PCA), the first three factors explain 81.553% of the total variance. Differences in head size between sexes have been well-documented in lizards and are associated with male-male aggression which results in mating success. This kind of pattern is supported by this study. Additionally, the results showed that males have more femoral pores, which is a

All statistical analyses were conducted using Statistical Package for the Social Sciences SPSS v24.Means, standard error of the mean, minimum and maximum values for each variable were calculated.To determine the characteristics that contribute to the discrimination of sexes, analysis of variance (ANOVA) were performed since all variables exhibited normal distribution.Considering the results of ANOVA, one morphometric and six meristic characteristics were discarded because they were uninformative.Finally, principal component analysis (PCA) was performed to detect the size of variation between sexes at the multivariate level using the remaining informative variables (ten for both morphometric and meristic).The significance level for all statistical tests was set at 0.05.
The results of ANOVA showed that all morphometric features exhibited a pattern in which males had larger size than females (Table 2).Among these characteristics, SVL alone did not vary depending on sex considering the significance level (p=0.441,Table 4), while the other features appear to have significant differences (all p values are less than 0.05, Table 2).Similarly, males had larger values for many metric characteristics than females, except for PON, VL and SBLL.PON and VL in females were significantly larger than males and provided discrimination when considering sex-dependent variety (p=0.008 and F=7.344 for PON, p=0.000 and F=13.603 for VL, Tables 3 and 4).PCA was performed to compare sexes at a multivariate level using all morphological variables which were standardized to obtain an unbiased statistical analysis (Figure 1).Considering the results of PCA, PON was not correlated with other characteristics, and SPCL, PPL and PAN which had less than 0.50 values of communalities and were discarded.According to PCA, the first three factors explained 81.553% of the total variance (Table 5).The most crucial contributors to the first component (PC1), which explained 54.043%, were determined to be PL, PW, HL, HW, FLL, HLL and PAL, while SDLL, SDLR, FPL, FPR and GU were the main contributors to the second component (PC2) which explained 20.684%.Also, 6.868% of variance was explained by PC3 that included VL, FPL and FPR, which play the most important roles (Table 5).Loadings from principal component analysis of metric and meristic characteristics.Variables in bold represent strong loadings.To compare SD in reptiles, scientists believe that body size should be used as a potential determinant and indicator of reproductive output [5,15,22,23].Rensch's rule, which is a common perspective for SSD, stated there were two major issues: (i) females are prone to be larger than males in small species, whereas males are larger than females in large species and (ii) SSD increases with size when males are the larger sex and decreases with size when females are the larger sex [5,14,22,[24][25][26][27][28].In most lizards, males represent the larger body size, which is related to physical advantages that are critical for territorial defence and mating success [17][18][19].Combat success between males is generally positively correlated with larger body size [15,29].

Variables
Considering morphometric characteristics which are closely related to body size, our results showed that males have larger size than females (Tables 2 and 3).Although a statistically significant difference could not be obtained, males were relatively larger than females in terms of SVL.Head size, another important size characteristic, showed that males were significantly larger than females (Table 2).Differences in head size between sexes were well-documented in lizards and associated with male-male aggression which results in mating success [30][31][32][33].
Males with larger heads may produce greater bite force and they can use this to provide a mating advantage by repelling other males [13,34,35].This kind of pattern is also supported by our study considering HW, HL, PW and PL are larger in males than females (Table 2).Considering another lizard species in the same genus, A. yassujica, the species has a similar pattern based on the larger male theory [5].
As another important point of discrimination between sexes, femoral pores are also useful characteristics in lacertid lizards [15,23].Femoral pores are clear and large in males because of holocrine secretion which is a signalling mechanism for sexual selection during the reproductive period [36][37][38].Our results showed that males (mean for left/right side: 22.24/22.37)have significantly more femoral pores than females (mean for left/right side: 20.61/20.69)(Table 3).Similar results were found for A. yassujica [5].Based on these conditions, species in the genus Apathya exhibit the expected pattern for lacertids.

Declaration of Competing Interests
The authors declare no conflict of interest.

Figure 1 .
Figure 1.Ordination of individual males and females of Apathya cappadocica on the first two principal components.
Results of the one-way ANOVA test for metric characteristics for both sexes.SEM: Standard.Error Mean, D of d: Direction of difference, Min: Minimum value; Max: Maximum value.All measurements are shown in millimetres.Results of one-way ANOVA test for meristic characteristics for both sexes.SEM: Standard.Error Mean, D of d: Direction of difference, Min: Minimum value; Max: Maximum value.All measurements are shown in millimetres.