Yazar "Gundemir, Ozan" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    A Different Perspective on Sex Dimorphism in the Adult Hermann's Tortoise: Geometric Morphometry
    (Biodiversity Research Center, Acad Sinica, 2021) Duro, Sokol; Gundemir, Ozan; Sonmez, Bektas; Jashari, Tefik; Szara, Tomasz; Pazvant, Gulsun; Kambo, Arben
    Eastern Hermann's tortoise (Testudo hermanni boettgeri) is a subspecies of Hermann's tortoise (Testudo hermanni) found in Albania. Gender determination is one of the crucial elements in determining the population dynamics in all species. Female and male adult tortoises look different, but these differences can be difficult to distinguish in captivity or when their sex indicators are deformed or injured. Therefore, the aim of this study was to use indirect and non-invasive methods such as geometric morphometric analysis to determine the sex of adult tortoises. For the geometric morphometry, 17 female and 23 male Hermann's tortoises were collected and photographed from the hills and mountains around the Tirana district of Albania between August and October 2019. Sexes were discriminated based on geometric morphometry, and plastron shape was a better indicator than carapace shape. In addition, abdominal, femoral and anal scutes on the plastron and the ratio of femoral to pectoral suture lengths were important for the sex distinction. Females had a larger plastron than males; this may have been supported by fecundity selection, because a large plastron suggests more volume in which to store eggs. The femoral and anal scutes were larger in male tortoises, and serve as a stronger base during mating. This study was conducted for adults only, and future studies are needed to determine if these indicators also apply to hatchlings and juveniles.
  • Küçük Resim Yok
    Öğe
    Carapace Morphology Variations in Captive Tortoises: Insights from Three-Dimensional Analysis
    (Mdpi, 2024) Yalin, Ebru Eravci; Gundemir, Ozan; Gunay, Ebuderda; celik, Ezgi Can Vatansever; Duro, Sokol; Szara, Tomasz; Blagojevic, Milos
    The carapace morphology of tortoises is a crucial characteristic used for species identification, with features such as shell shape, roughness, and color patterns varying among species. Understanding this morphological diversity is valuable not only for taxonomic classification but also for more specialized clinical approaches. This study investigated the morphological differences in the shells of Leopard tortoises (Stigmochelys pardalis), African spurred tortoises (Centrochelys sulcata), and Greek tortoises (spur-thighed tortoises; Testudo graeca) raised in captivity. Using 3D scanners, the carapaces were modeled, and a 3D geometric morphometric method was employed to analyze shape variations and dimensional features, with landmarks applied automatically. Among the species studied, African spurred tortoises had the largest carapace size. Principal component analysis (PCA) identified PC1 and PC3 as critical factors in distinguishing between species based on morphological characteristics. Positive PC1 values, associated with a shorter carapace height, indicated a flatter or more compact shell shape. A higher PC3 value corresponded to a raised shape at the back of the shell, while a lower PC3 value indicated a raised shape at the front. Specifically, Leopard tortoises exhibited a higher carapace shape than the other species, while African spurred tortoises had shorter carapaces. An allometric effect was observed in the carapaces, where smaller specimens tended to be proportionately higher-domed, whereas larger shells displayed a lower height in shape. These findings highlight the significance of shape variations in tortoise shells, which emerge during adaptation and have important implications for taxonomy and clinical practice. Such differences should be carefully considered in veterinary care and species identification.