TY  - JOUR
AU  - Arntzen, Jan W.
AU  - Üzüm, Nazan
AU  - Ajduković, Maja
AU  - Ivanović, Ana
AU  - Wielstra, Ben
PY  - 2018
UR  - https://peerj.com/articles/5317
UR  - https://radar.ibiss.bg.ac.rs/handle/123456789/3120
AB  - Relationships between phylogenetic relatedness, hybrid zone spatial structure, the amount of interspecific gene flow and population demography were investigated, with the newt genus Triturus as a model system. In earlier work, a bimodal hybrid zone of two distantly related species combined low interspecific gene flow with hybrid sterility and heterosis was documented. Apart from that, a suite of unimodal hybrid zones in closely related Triturus showed more or less extensive introgressive hybridization with no evidence for heterosis. We here report on population demography and interspecific gene flow in two Triturus species ( T. macedonicus and T. ivanbureschi in Serbia). These are two that are moderately related, engage in a heterogeneous uni-/bimodal hybrid zone and hence represent an intermediate situation. This study used 13 diagnostic nuclear genetic markers in a population at the species contact zone. This showed that all individuals were hybrids, with no parentals detected. Age, size and longevity and the estimated growth curves are not exceeding that of the parental species, so that we conclude the absence of heterosis in T. macedonicus – T. ivanbureschi . Observations across the genus support the hypothesis that fertile hybrids allocate resources to reproduction and infertile hybrids allocate resources to growth. Several Triturus species hybrid zones not yet studied allow the testing of this hypothesis.
T2  - PeerJ
T1  - Absence of heterosis in hybrid crested newts
VL  - 6
DO  - 10.7717/peerj.5317
SP  - e5317
ER  - 

@article{
author = "Arntzen, Jan W. and Üzüm, Nazan and Ajduković, Maja and Ivanović, Ana and Wielstra, Ben",
year = "2018",
abstract = "Relationships between phylogenetic relatedness, hybrid zone spatial structure, the amount of interspecific gene flow and population demography were investigated, with the newt genus Triturus as a model system. In earlier work, a bimodal hybrid zone of two distantly related species combined low interspecific gene flow with hybrid sterility and heterosis was documented. Apart from that, a suite of unimodal hybrid zones in closely related Triturus showed more or less extensive introgressive hybridization with no evidence for heterosis. We here report on population demography and interspecific gene flow in two Triturus species ( T. macedonicus and T. ivanbureschi in Serbia). These are two that are moderately related, engage in a heterogeneous uni-/bimodal hybrid zone and hence represent an intermediate situation. This study used 13 diagnostic nuclear genetic markers in a population at the species contact zone. This showed that all individuals were hybrids, with no parentals detected. Age, size and longevity and the estimated growth curves are not exceeding that of the parental species, so that we conclude the absence of heterosis in T. macedonicus – T. ivanbureschi . Observations across the genus support the hypothesis that fertile hybrids allocate resources to reproduction and infertile hybrids allocate resources to growth. Several Triturus species hybrid zones not yet studied allow the testing of this hypothesis.",
journal = "PeerJ",
title = "Absence of heterosis in hybrid crested newts",
volume = "6",
doi = "10.7717/peerj.5317",
pages = "e5317"
}

Arntzen, J. W., Üzüm, N., Ajduković, M., Ivanović, A.,& Wielstra, B.. (2018). Absence of heterosis in hybrid crested newts. in PeerJ, 6, e5317.
https://doi.org/10.7717/peerj.5317

Arntzen JW, Üzüm N, Ajduković M, Ivanović A, Wielstra B. Absence of heterosis in hybrid crested newts. in PeerJ. 2018;6:e5317.
doi:10.7717/peerj.5317 .

Arntzen, Jan W., Üzüm, Nazan, Ajduković, Maja, Ivanović, Ana, Wielstra, Ben, "Absence of heterosis in hybrid crested newts" in PeerJ, 6 (2018):e5317,
https://doi.org/10.7717/peerj.5317 . .

TY  - JOUR
AU  - Cvijanović, Milena
AU  - Üzüm, Nazan
AU  - Ivanović, Ana
AU  - Avci, Aziz
AU  - Özcan, Çiçek Gümüş
AU  - Olgun, Kurtuluş
PY  - 2017
UR  - https://www.thebhs.org/publications/the-herpetological-journal/volume-27-number-1-january-2017
UR  - https://radar.ibiss.bg.ac.rs/handle/123456789/2804
AB  - According to Rensch’s rule, sexual size dimorphism (SSD) increases with body size in groups where males are the larger sex and decreases when females are larger. The genus Ommatotriton represents a well-defined lineage with male-biased SSD within a group of Eurasian newts otherwise characterised by females being larger than males. In the present paper, we explore sexual dimorphism in skull size and shape for populations of the banded newt Ommatotriton ophryticus, applying geometric morphometrics to investigate size-dependent allometric shape variation. Sexual dimorphism in skull size was not correlated with the size of males, rejecting Rensch’s rule. Sexual dimorphism in skull shape of O. ophryticus is entirely due to allometric, size-related shape changes between sexes.
T2  - Herpetological Journal
T1  - Variation in skull size and shape in a newt species with male-biased sexual dimorphism
IS  - 1
VL  - 27
SP  - 41
EP  - 46
UR  - https://hdl.handle.net/21.15107/rcub_ibiss_2804
ER  - 

@article{
author = "Cvijanović, Milena and Üzüm, Nazan and Ivanović, Ana and Avci, Aziz and Özcan, Çiçek Gümüş and Olgun, Kurtuluş",
year = "2017",
abstract = "According to Rensch’s rule, sexual size dimorphism (SSD) increases with body size in groups where males are the larger sex and decreases when females are larger. The genus Ommatotriton represents a well-defined lineage with male-biased SSD within a group of Eurasian newts otherwise characterised by females being larger than males. In the present paper, we explore sexual dimorphism in skull size and shape for populations of the banded newt Ommatotriton ophryticus, applying geometric morphometrics to investigate size-dependent allometric shape variation. Sexual dimorphism in skull size was not correlated with the size of males, rejecting Rensch’s rule. Sexual dimorphism in skull shape of O. ophryticus is entirely due to allometric, size-related shape changes between sexes.",
journal = "Herpetological Journal",
title = "Variation in skull size and shape in a newt species with male-biased sexual dimorphism",
number = "1",
volume = "27",
pages = "41-46",
url = "https://hdl.handle.net/21.15107/rcub_ibiss_2804"
}

Cvijanović, M., Üzüm, N., Ivanović, A., Avci, A., Özcan, Ç. G.,& Olgun, K.. (2017). Variation in skull size and shape in a newt species with male-biased sexual dimorphism. in Herpetological Journal, 27(1), 41-46.
https://hdl.handle.net/21.15107/rcub_ibiss_2804

Cvijanović M, Üzüm N, Ivanović A, Avci A, Özcan ÇG, Olgun K. Variation in skull size and shape in a newt species with male-biased sexual dimorphism. in Herpetological Journal. 2017;27(1):41-46.
https://hdl.handle.net/21.15107/rcub_ibiss_2804 .

Cvijanović, Milena, Üzüm, Nazan, Ivanović, Ana, Avci, Aziz, Özcan, Çiçek Gümüş, Olgun, Kurtuluş, "Variation in skull size and shape in a newt species with male-biased sexual dimorphism" in Herpetological Journal, 27, no. 1 (2017):41-46,
https://hdl.handle.net/21.15107/rcub_ibiss_2804 .