Contact zone and hybridization of oviparous and viviparous common lizard lineages (Zootoca vivipara) in Slovenia

Kekec, Blaž (avtor), Trontelj, Peter (mentor), Recknagel, Hans (komentor)

The thesis investigates lineage distribution and phenotypic variation in the common lizard (Zootoca vivipara) on Pohorje and Pokljuka, examining variation both within and among lineages. The species is exceptional due its reproductive bimodality, meaning that both oviparous and viviparous lineages occur within the species. This has been reported only in three lizard species. The aim was to identify which oviparous and viviparous lineages occur in the study areas, assess whether the lineages come into contact and test whether they differ in morphological traits. 195 lizards were captured, measured and photographed; tissue samples were collected for cyt b genotyping. Females were kept in captivity until reproduction to determine parity mode and to screen for hybridization based on reproductive traits. Uni - and multivariate linear models, and PCA were used to test for sex and lineage-related variation. Genetic analyses revealed the presence of the eastern oviparous (EO), central viviparous II (CVII), and western viviparous (WV) lineages. No hybrids were detected. Results showed sexual dimorphism: females were larger in body size but smaller in head and tail measurements. Lineage effects were inconsistent and limited to specific traits. Linear models suggested larger head and pileus length, tail length and body mass in the EO lineage. MANOVA indicated lineage differences mainly in head measures and mass, with larger values in the CVII lineage. PCA showed overlap between lineages and highlighted sex as the dominant source of morphological variation. Coloration differed between sexes, but no significant lineage effect was detected. Reproductive traits differed clearly between lineages: oviparous females produced larger clutches with greater clutch mass and a longer incubation period, whereas viviparous females produced offspring later with near-immediate emergence. Oviparous offspring were longer and heavier at emergence.

• Jezik: Angleški jezik
• Ključne besede: reptiles, Zootoca, viviparity, oviparity, reproductive mode, parity mode, morphological measurements, morphology
• Vrsta gradiva: Magistrsko delo/naloga
• Tipologija: 2.09 - Magistrsko delo
• Organizacija: BF - Biotehniška fakulteta
• Založnik: [B. Kekec]
• Leto izida: 2026
• PID: 20.500.12556/RUL-181521
• UDK: 598.161.21:591.37(043.2)
• COBISS.SI-ID: 274785283
• Datum objave v RUL: 10.04.2026

Sekundarni jezik

• Jezik: Slovenski jezik
• Naslov: Prekrivanje arealov in hibridizacija oviparne in viviparne linije živorodne kuščarice (Zootoca vivipara) v Sloveniji

Izvleček

Magistrsko delo je preučevalo razširjenost linij in fenotipsko variabilnost pri živorodni kuščarici (Zootoca vivipara) na območjih Pohorja in Pokljuke. Vrsta je izjemna zaradi reproduktivne bimodalnosti, kar pomeni, da se znotraj vrste pojavljajo tako jajcerodne kot živorodne linije. To je bilo dokumentirano le pri treh vrstah kuščarjev po svetu. Namen raziskave je bil ugotoviti prisotnost jajcerodnih in živorodnih linij, oceniti morebiten stik med njimi ter preveriti razlike v morfoloških znakih. Skupno je bilo ujetih, izmerjenih in fotografiranih 195 osebkov; odvzeti so bili tkivni vzorci za genotipizacijo gena cyt b. Samice so bile zadržane v ujetništvu do reprodukcije za določitev paritetnega načina in preverjanje morebitne hibridizacije med linijami. Razlike med spoloma in linijami so bile analizirane z linearnimi modeli, MANOVA in PCA. Genetske analize so pokazale prisotnost centralne živorodne linije II, vzhodnoevropske jajcerodne in zahodnoevropske živorodne linije, fenotipski podatki pa niso potrdili prisotnosti hibridov. Rezultati so pokazali izrazit spolni dimorfizem: samice so imele večje mere telesa ter manjše mere glave in repa. Učinki linije so bili omejeni na posamezne lastnosti. Linearni modeli so kazali večje mere glave in pileusa, daljši rep ter večjo telesno maso pri jajcerodni liniji, medtem ko je MANOVA pokazala razlike predvsem v merah glave in telesni masi, z večjimi vrednostmi pri centralni viviparni liniji. Analiza PCA je pokazala znatno prekrivanje med linijami in izpostavila spol kot glavni vir morfološke variabilnosti. Obarvanost se je razlikovala med spoloma, brez pomembnega učinka linije. Reprodukcijski znaki so se med linijami jasno razlikovali: jajcerodne samice so imele večja in težja legla z daljšo inkubacijsko dobo, medtem ko so živorodne samice potomce proizvedle kasneje, s skoraj takojšnjim izvalitvijo mladičev. Jajcerodni mladiči so bili ob izvalitvi daljši in težji.

• Ključne besede: plazilci, viviparija, oviparija, način razmnoževanja, morfometrične meritve, morfologija, biogeografija, primerjalna anatomija