Effects of biotic and abiotic stressors on asymmetries and head size in two sympatric lizard species

2021 ◽  
pp. 1-19
Author(s):  
Ajša Alagić ◽  
Miha Krofel ◽  
Marko Lazić ◽  
Anamarija Žagar
Keyword(s):  
Sexual Dimorphism ◽  
Habitat Degradation ◽  
Mixed Effects ◽  
Environmental Stressors ◽  
Lizard Species ◽  
Efficient Tool ◽  
Altitude Effect ◽  
Podarcis Muralis ◽  
Abiotic Stressors ◽  
Head Morphology

Abstract Organisms face numerous environmental stressors, which can affect developmental precision, including symmetry of various physical characteristics. Fluctuating asymmetry (FA) has therefore been suggested as a simple and efficient tool for assessing sub-lethal stress levels. We analyzed FA in two sympatric lizard species (Iberolacerta horvathi and Podarcis muralis) to determine potential effects of interspecific competition and urbanization, as proxies of stress, taking into account sexual dimorphism and environmental conditions. We sampled 16 syntopic and allotopic populations and used geometric morphometrics of head morphology. We detected significant but mixed effects on the head asymmetry from the environment and the syntopic occurrence that differed between species. P. muralis lizards had more asymmetric heads at higher altitudes, while I. horvathi lizards did at mid altitudes, which may be explained by P. muralis experiencing environmental stress of colder conditions at higher altitudes. The mid-altitude effect on asymmetries in I. horvathi might be explained by a lower availability of stony walls and higher abundance of P. muralis, thus higher competition. The asymmetry of supraciliary granules was affected by the presence of other species. However, lizards from allotopic populations attained larger asymmetries compared to lizards from syntopic populations, which was the opposite from what was expected. There was no effect of urbanization in P. muralis, which could be due to relatively low pollution and habitat degradation in study locations. Overall, we highlighted the possibility of using lizards and FA for bioindication of environmental stressors and especially improved the knowledge gap in the research of biotic stressors.

Sexual dimorphism in digit length ratios in two lizard species

2006 ◽  
Vol 288A (5) ◽  
pp. 491-497 ◽  
Author(s):  
Diego Rubolini ◽  
Fabio Pupin ◽  
Roberto Sacchi ◽  
Augusto Gentilli ◽  
Marco A.L. Zuffi ◽  
...  
Keyword(s):  
Sexual Dimorphism ◽  
Lizard Species ◽  
Digit Length

Head morphological variation in Podarcis muralis and Podarcis sicula: a landmark-based approach

2007 ◽  
Vol 28 (4) ◽  
pp. 566-573 ◽  
Author(s):  
David Costantini ◽  
Emiliano Bruner
Keyword(s):  
Euclidean Distance ◽  
Distance Matrix ◽  
Matrix Analysis ◽  
Head Shape ◽  
Euclidean Distance Matrix ◽  
Podarcis Muralis ◽  
Podarcis Sicula ◽  
Head Morphology ◽  
Species Specific ◽  
Range Of Variation

Abstract The geometry of the cephalic scales in lizards is easily represented by using landmark based approaches. The cephalic scales may prove useful structures in the investigation of the evolution and morphogenesis of lizards because of their biomechanical relationships with the underlying bones and muscular anatomy. In the present paper the head morphology in Podarcis muralis and Podarcis sicula is compared by using geometric morphometrics and Euclidean distance matrix analysis. The head shape in these two species is largely influenced by a shared allometric pattern, with P. sicula displaying a reduced range of variation. This pattern is probably influenced by the cranial morphogenesis at the fronto-parietal suture, and by the parieto-occipital musculature involved in diet and social behaviours. Minor species-specific differences are evidenced, and should be further investigated.

scholarly journals The first Miocene fossils of Lacerta cf.trilineata(Squamata, Lacertidae) with a comparative study of the main cranial osteological differences in green lizards and their relatives

2019 ◽  
Author(s):  
Andrej Čerňanský ◽  
Elena V. Syromyatnikova
Keyword(s):  
Comparative Study ◽  
Late Miocene ◽  
Fossil Record ◽  
Calibration Point ◽  
Lizard Species ◽  
Podarcis Muralis ◽  
Modern Species ◽  
Zootoca Vivipara ◽  
Morphological Differences ◽  
Important Evidence

AbstractWe here describe the first fossil remains of a green lizardof theLacertagroup from the late Miocene (MN 13) of the Solnechnodolsk locality in southern European Russia. This region of Europe is crucial for our understanding of the paleobiogeography and evolution of these middle-sized lizards. Although this clade has a broad geographical distribution across the continent today, its presence in the fossil record has only rarely been reported. In contrast to that, the material described here is abundant, consists of a premaxilla, maxillae, frontals, parietals, jugals, quadrate, pterygoids, dentaries and vertebrae. The comparison of these elements to all extant green lizard species shows that these fossils are indistinguishable fromLacerta trilineata. Thus, they form the first potential evidence of the occurrence of this species in the Miocene. This may be also used as a potential calibration point for further studies. Together with other lizard fossils, Solnechnodolsk shows an interesting combination of survivors and the dawn of modern species. This locality provides important evidence for the transition of an archaic Miocene world to the modern diversity of lizards in Europe. In addition, this article represents a contribution to the knowledge of the comparative osteological anatomy of the selected cranial elements in lacertid. This study gives special emphasis to the green lizards, but new data are also presented for related taxa, e.g.,Timon lepidus, Podarcis muralisorZootoca vivipara. Although the green lizards include several cryptic species for which determination based on isolated osteological material would be expected to be difficult, our comparisons show several important morphological differences.

scholarly journals Habitat degradation of an eelgrass bed variably affects epifaunal biodiversity

2018 ◽  
Author(s):  
Francesca Rossi ◽  
Marie Pierrejean
Keyword(s):  
Species Diversity ◽  
Zostera Marina ◽  
Habitat Complexity ◽  
Photosynthetic Activity ◽  
Habitat Degradation ◽  
Shoot Density ◽  
Seagrass Habitat ◽  
Abiotic Stressors ◽  
Complex Patterns ◽  
Epifaunal Assemblages

Seagrass habitat complexity can determine species diversity and abundance, through, for instance, changes in the availability of microhabitats, refuge from predators or changes in the intensity and frequency of abiotic stressors. Human-related perturbations cause seagrass habitat degradation and, therefore, reduce its complexity, thereby affecting biodiversity. We have followed the epifaunal assemblages of a Zostera marina meadow and deliberately modified seagrass shoot density three times during a year to measure how epifaunal assemblages responded to habitat degradation and whether patterns of response were consistent through time. We have also measured in the laboratory how epifauna controlled epiphyte biomass, which could feedback on seagrass photosynthetic activity, growth and productivity, thereby changing its resilience to disturbances. Results have shown complex patterns, variable in time.

scholarly journals Habitat degradation of an eelgrass bed variably affects epifaunal biodiversity

2018 ◽  
Author(s):  
Francesca Rossi ◽  
Marie Pierrejean
Keyword(s):  
Species Diversity ◽  
Zostera Marina ◽  
Habitat Complexity ◽  
Photosynthetic Activity ◽  
Habitat Degradation ◽  
Shoot Density ◽  
Seagrass Habitat ◽  
Abiotic Stressors ◽  
Complex Patterns ◽  
Epifaunal Assemblages

Seagrass habitat complexity can determine species diversity and abundance, through, for instance, changes in the availability of microhabitats, refuge from predators or changes in the intensity and frequency of abiotic stressors. Human-related perturbations cause seagrass habitat degradation and, therefore, reduce its complexity, thereby affecting biodiversity. We have followed the epifaunal assemblages of a Zostera marina meadow and deliberately modified seagrass shoot density three times during a year to measure how epifaunal assemblages responded to habitat degradation and whether patterns of response were consistent through time. We have also measured in the laboratory how epifauna controlled epiphyte biomass, which could feedback on seagrass photosynthetic activity, growth and productivity, thereby changing its resilience to disturbances. Results have shown complex patterns, variable in time.

Intraspecific variation in morphology and sexual dimorphism in Liolaemus tenuis (Tropiduridae)

2005 ◽  
Vol 26 (3) ◽  
pp. 343-351 ◽  
Author(s):  
Madeleine Lamborot ◽  
Marcela Vidal ◽  
Claudio Ramírez ◽  
Juan Carlos Ortiz
Keyword(s):  
Sexual Dimorphism ◽  
Morphological Variation ◽  
Latitudinal Gradient ◽  
Geometric Approach ◽  
Climatic Conditions ◽  
Territorial Defense ◽  
Lizard Species ◽  
Distribution Ranges ◽  
Morphological Variables ◽  
Wide Geographic Distribution

AbstractLiolaemus tenuis is a widely distributed arboreal lizard species in central-southern Chile. Although two subspecies, L. t. tenuis and L. t. punctatissimus, have been described based on sexual dimorphism, their characteristic have not been accurately demarcated. Therefore, both traditional and geometric morphometrics were used to study the morphological variation of L. tenuis. Four specific questions were addressed: (1) Does population morphological variation occur along a latitudinal gradient, given its wide geographic distribution in a climactic gradient? (2) Does L. tenuis present sexual dimorphism? (3) In the case of dimorphism, what is the variation along a latitudinal gradient? (4) Are these subspecies morphologically distinguishable? The study was performed in a variety of locations, including the following six bioclimatic regions of Chile: arid mediterranean, semi-arid mediterranean, sub-humid mediterranean, humid mediterranean, per-humid mediterranean, and oceanic with mediterranean influence. Male and female individuals were measured and photographed. Our results suggest sexual dimorphism for all morphological variables analyzed. Geometric data indicate that the eye orbits of the males are more extended than those of the females; this is probably related to territorial defense and/or polygynic mating system. The traditional morphometric approach revealed a difference in individuals from the arid region, whereas the geometric approach revealed a difference in individuals from the oceanic region. Differences in the limits of their distribution ranges seem be related to local factors, such as topography and climatic conditions. Finally, is not possible to recognize distinct subspecies within L. tenuis, and our research concludes that the species consists of one homogenous identity.

Régime Alimentaire d'une Population de Lézard des Murailles, Podarcis muralis (Laurent, 1768) dans le Sud-Ouest de la France

1986 ◽  
Vol 7 (2) ◽  
pp. 171-180 ◽  
Author(s):  
Robert Barbault ◽  
Yung-Ping Mou
Keyword(s):  
Interannual Variation ◽  
Prey Size ◽  
Taxonomic Diversity ◽  
High Population Density ◽  
Lizard Species ◽  
Podarcis Muralis ◽  
Food Items ◽  
South West ◽  
Wide Range ◽  
Close Relationship

AbstractDiet and its variations as a function of time and of lizard size were studied in a natural population of Podarcis muralis in the south-west of France during 1980 and 1981. The taxonomic diversity of the ingested food items, the wide range of prey size, the absence of a close relationship between prey and predator size, and the seasonal and interannual variation of the composition of the diet emphasize the alimentary opportunism of this lizard species. Such opportunism is supposed to be related to the ecological conditions of the studied population, which include high population density, low prey productivity within the biotope, unpredictable variability of prey abundance, and low interspecific competitive pressure.

scholarly journals Microcalorimetric Investigations on the Energy Metabolism of Lizards

1991 ◽  
Vol 156 (1) ◽  
pp. 375-385
Author(s):  
I. H. D. LAMPRECHT ◽  
F.-R. MATUSCHKA ◽  
B. SCHAARSCHMIDT
Keyword(s):  
Energy Metabolism ◽  
Heat Dissipation ◽  
Locomotory Activity ◽  
Lizard Species ◽  
Podarcis Muralis ◽  
Anaerobic Energy ◽  
Resting Metabolism ◽  
The Mean ◽  
Lacerta Agilis ◽  
Environmental Temperatures

The energy metabolism of three lizard species (Podarcis milensis, Podarcis muralis and Lacerta agilis) was investigated by means of microcalorimetry and polarography over the range of environmental temperatures between 17 and 35 °C encountered by active lizards during summer in Europe. In non-stimulated animals, the maximum and mean heat production rates were highest around 30°C for all species and amounted to 3.9±1.1 mWg−1 and 2.1±0.5 mWg−1, respectively. Resting metabolism contributed approximately 60% to the mean routine heat dissipation; the remainder originated from locomotory activity, 43% of which was based on anaerobic energy metabolism. From simultaneous determinations of heat dissipation and oxygen consumption, an average oxycaloric equivalent of 18.6±3.2 J ml−1 O2 was calculated, which rose to 26.6±7.1 J ml−1 O2 during short bursts of locomotion. Note: Institut für Physiologie, Ruhr-Universitat Bochum, Universitätsstrasse 150, D-4630 Bochum, Germany.

Sign in / Sign up

Export Citation Format

Share Document