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Povzetek: Understanding how communication systems evolve across heterogeneous environments requires examining multiple signalling modalities. In 2017 and 2018, we examined geographic variation in chemical signals of the insular lizard Gallotia galloti across 16 sites on Tenerife (Canary Islands). We analysed interpopulation variation in the lipophilic fraction of male femoral gland secretions in relation to vegetation cover (NDVI), local sex ratio, ectoparasite load and macroclimatic factors. In 2023, we also analysed visual signals of two lizard phenotypes that occur in contrasting habitats of Tenerife. We modelled the chromatic and achromatic conspicuousness of colour patches under both a conspecific (lacertid) and an avian predator visual system to examine habitat-dependent divergence in signal detectability. Chemical signal diversity decreased with increasing shrub vegetation cover, while males from sites with male-biased sex ratios exhibited greater individual chemical richness, consistent with heightened intrasexual competition. Populations in xeric habitats and with higher mite loads showed relatively higher proportions of α-tocopherol, whereas greener habitats were associated with higher proportions of steroids. In contrast, visual analyses revealed that lizards from densely vegetated habitats exhibited greater chromatic conspicuousness and larger chromatic volumes, particularly under the conspecific visual model. Achromatic contrast showed weaker habitat-dependent differentiation, consistent with the hypothesis that luminance divergence is constrained by predator-mediated selection due to the high luminance sensitivity of avian visual systems. Thus, in open habitats, persistent and chemically diverse secretions may enhance communication efficiency under increased exposure, whereas in vegetated environments chromatic visual signals appear to be amplified, potentially driven by sexual selection while constrained by predation risk. These findings suggest that environmental heterogeneity can promote complementary divergence across signalling modalities, highlighting the importance of integrating sensory ecology and social context to understand the evolution of animal communication.
Ključne besede: animal communication, ecological gradients, Gallotia galloti, local adaptation, sexual versus natural selection
Objavljeno v DiRROS: 31.07.2026; Ogledov: 144; Prenosov: 87
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Povzetek: Blood parasites play a crucial role in shaping host ecology and fitness in reptiles, yet their occurrence in many lacertid species remains poorly documented. We here report the first evidence of blood parasites in Zootoca carniolica, a recently recognized oviparous species, from Slovenia. Fifty adult lizards (25 males, 25 females) were sampled from a population at an elevation of 1300 m in Pokljuka, Slovenia, during the summer of 2021. Blood smears were analysed to determine parasite prevalence and intensity, and the relationships of parasite data with host body size, sex, and seasonality. Overall, 52% of individuals were infected. A distinct sex-specific pattern in parasite infection was found: in males, body size was positively correlated with parasite prevalence, likely reflecting increased exposure to potential parasite vectors through enhanced social interactions and movement in bigger males. In females, larger individuals exhibited higher parasite intensity, possibly due to trade-offs between reproductive investment and immune function, or cumulative parasite exposure with age. Additionally, females showed a significant seasonal decline in parasite intensity from July to August, which is potentially linked to reproductive cycles, environmental factors, or physiological condition. On the other hand, it might also reflect a body size effect since larger females were found in July. These findings highlight the complex interactions between host traits, seasonality, and parasite dynamics in a high-elevation lizard population, contributing to our understanding of host-parasite interactions in European lacertids.
Ključne besede: blood parasites, Lacertidae, Zootoca carniolica, reptiles, Apicomplexa, alpine habitat, Slovenia, host-parasite interactions
Objavljeno v DiRROS: 08.07.2026; Ogledov: 170; Prenosov: 123
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Povzetek: Understanding the processes driving the diversity of mountain herpetofauna requires a comprehensive examination of species diversification across evolutionary scales. Here, we investigate the phylogeography of Iberolacerta, a genus of eight lizard species mainly restricted to high elevations in southwestern Europe. Using genomic data, we reconstructed a nuclear phylogeny that aligns with mitochondrial evidence in supporting the divergence of all currently recognized species. Notably, we detect historical nuclear gene flow between I. cyreni and I. martinezricai in Central Spain, suggesting past range overlap, reminiscent of previously observed mitochondrial introgression between I. galani and I. monticola, and the lack of divergence between disjoint populations of I. monticola. Bioclimatic projections accordingly depict broader historical ranges during the last glacial maximum compared to interglacial and current conditions. At the intraspecific level, genomic analyses of four high-elevation species reveal that genetic structure is mainly shaped by isolation-by-distance and, in I. cyreni, by separation among mountain ranges, while heterozygosity generally decreases with elevation. These findings are consistent with the impact of glacial-interglacial cycles on the genetic diversity of montane taxa: populations experience genetic isolation and altitudinal bottlenecks during interglacial periods, but are reconnected and admix in lowland areas during glacial periods. These processes are expected to leave contrasting signatures between the mitochondrial and nuclear genomes, as well as between slow- and fast-evolving molecular markers. From a conservation perspective, our results highlight that the genetically richest – and potentially most adaptive – populations occur at the lowland edges of the species’ ranges, where they are also most vulnerable to climate change.
Ključne besede: biogeography, climate change, Lacertidae, RAD-seq, Europe
Objavljeno v DiRROS: 19.12.2025; Ogledov: 875; Prenosov: 624
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Povzetek: 1. Host abundance might favour the maintenance of a high phylogenetic diversity of some parasites via rapid transmission rates. Blood parasites of insular lizards represent a good model to test this hypothesis because these parasites can be particularly prevalent in islands and host lizards highly abundant. 2. We applied deep amplicon sequencing and analysed environmental predictors of blood parasite prevalence and phylogenetic diversity in the endemic lizard Gallotia galloti across 24 localities on Tenerife, an island in the Canary archipelago that has experienced increasing warming and drought in recent years. 3. Parasite prevalence assessed by microscopy was over 94% and a higher proportion of infected lizards was found in warmer and drier locations. A total of 33 different 18s rRNA parasite haplotype were identified and the phylogenetic analyses indicated that they belong to two genera of Adeleorina (Apicomplexa: Coccidia), with Karyolysus as the dominant genus. The most important predictor of between-locality variation in parasite phylogenetic diversity was the abundance of lizard hosts. 4. A combination of climatic and host demographic factors associated with an insular syndrome may be favouring a rapid transmission of blood parasites among lizards on Tenerife, which may favour the maintenance of a high phylogenetic diversity of parasites.
Ključne besede: lizards, parasites, genetics, biogeography, habitat, data
Objavljeno v DiRROS: 27.10.2025; Ogledov: 682; Prenosov: 558
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Povzetek: Potential Metabolic Activity (ETS26_P, ETS31_P, ETS36_P), Catalase Activity (CAT_P), Performance traits (BITE, SPRINT,CLIMB, MANO) and Morphological variables (snout-vent length (SVL), trunk length (TRL), pileus length (PL), head length (HL), head width (HW), head height (HH), fore limb length (FLL) and hind limb length (HLL) of 94 individuals belonging to Podarcis muralis species. The data was used in the analysis of the paper entitled: Is It Function or Fashion? An Integrative Analysis of Morphology, Performance, and Metabolism in a Colour Polymorphic Lizard, by authors Verónica Gomes, Anamarija Žagar, Guillem Pérez i de Lanuza, Tatjana Simčič and Miguel A. Carretero, published in the journal Diversity 2022, 14, 116. https://doi.org/10.3390/d14020116
Ključne besede: lizards, morphology, viviparity, sexual dimorphism, climate change, data
Objavljeno v DiRROS: 27.10.2025; Ogledov: 852; Prenosov: 561
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