VOLUM OMAGIAL - Facultatea de Ştiinţe ale Naturii şi Ştiinţe Agricole

Rodica Plăiaşu et al. / Ovidius University Annals, Biology-Ecology Series 14: 121-126 (2010)
Table 3. Comparison of SVL and W between the three R. temporaria populations, by using ANCOVA (FN =
Finland - Kilpisjarvi; FS = Finland - Kolari, RNP = Retezat high altitude; N = sample size, *P < 0.05, ***P <
0.001, NS = not significant).
W SVL
N Average Fa Average Fa
FN vs FS FN FS FS FN FS FN
Female 13 16 18.956 14.308 6.069* 71.244 61.154 26.384***
Male 17 9 17.267 15.853 0.737 NS
69.89 62.46 22.88***
Juveniles 50 9 4.333 7.779 10.381* 42.17 45.95 1.748 NS
FN vs RNP FN RNP FN RNP FN RNP
Female 13 14 14.308 34.69 19.504*** 61.154 76.78 3.627 NS
Male 17 22 15.853 36.20 17.93*** 62.46 73.41 1.778 NS
Juveniles 50 7 7.779 9.28 5.903* 45.95 44.8 0.198 NS
Table 4. Comparison of the interannual variation in SVL and W between the three R. temporaria populations, by
using ANCOVA (FN = Finland - Kilpisjarvi; FS = Finland - Kolari, RNP = Retezat high altitude; N = sample
size, *P < 0.05, ***P < 0.001, NS = not significant).
W SVL
N Average Fa Average Fa
FN 2003 vs. 2009 2003 2009 2003 2009 2003 2009
Female 29 13 31 14.308 4.235* 65.94 61.154 3.70 NS
Male 32 17 31.76 15.853 3.713 NS
67.59 62.46 0.43 NS
Juveniles 197 50 3.17 7.779 78.41*** 29.01 45.95 120.01***
RNP 2004 vs. 2009 2004 2009 2004 2009 2004 2009
Female 14 14 61.16 34.69 14.56*** 82.7 76.78 2.24 NS
Male 35 22 47.14 36.20 12.21*** 77.07 73.41 4.49*
Juveniles 40 7 2.19 9.28 22.56*** 24.42 44.8 19.4***
The variation in the adult body size reported in
amphibians can be induced by several factors,
including genetic and environmental differences,
such as: duration of the activity period, food
availability and climatic conditions [6, 14]. Laugen
et al. (2005) found that body size decreased with
latitude in the Scandinavian Common Frog
populations. Comparisons between populations from
Western Europe with different activity periods report
increases in the mean length, as activity period gets
shorter [6]. Rana temporaria populations from the
analyzed area show a variable pattern in weight and
length. Băncilă et al. (2010) found that latitudinal and
altitudinal variation patterns in juvenile body size
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were according to the Bergmann’s rule. We found an
opposite pattern for juveniles, with decreases in the
body size as the activity period gets shorter. Since
juveniles have higher growth and development rate
than adults, difference could be observed even in the
case of short periods of time between sampling.
Interpopulational variation in the adult body size
could be caused by differences in the age structure.
Growth rates in amphibian species can dramatically
decrease after the attainment of sexual maturity (e.g.
Miaud et al. 1999). Thus, delayed reproduction can
allow a prolonged growth period and the attainment
of a larger adult size.