Urban areas as habitats for reptiles: the relative importance of environmental variables in predicting occurrence of common wall lizards Podarcis muralis

Little is known about the mating system of the common wall lizard Podarcis muralis. Behavioural and observational data have demonstrated that females frequently mate with multiple males. However, the possible occurrence of multiple paternity has never been investigated. By using microsatellite paternity analysis in a wild population, we document this species indeed mate promiscuously and these matings resulted in multiple paternity in at least 87% of the clutches examined.

Phospholipid fatty acid (PLFA) profiles were measured in soils from organic, low-input, and conventional farming systems that are part of the long term Sustainable Agriculture Farming Systems (SAFS) Project. The farming systems differ in whether their source of fertilizer is mineral or organic, and in whether a winter cover crop is grown. Sustained increases in microbial biomass resulting from high organic matter inputs have been observed in the organic and low-input systems. PLFA profiles were compared to ascertain whether previously observed changes in biomass were accompanied by a change in the composition of the microbial community. In addition, the relative importance of environmental variables on PLFA profiles was determined. Redundancy analysis ordination showed that PLFA profiles from organic and conventional systems were significantly different from April to July. On ordination plots, PLFA profiles from the low-input system fell between organic and conventional systems on most sample dates. A group of fatty acids (i14:0, a15:0, 16:1ω7c, 16:1ω5c, 14:0, and 18:2ω6c) was enriched in the organic plots throughout the sampling period, and another group (10Me16:0, 2OH 16:1 and 10Me17:0) was consistently lower in relative abundance in the organic system. In addition, another group (15:0, a17:0, i16:0, 17:0, and 10Me18:0) was enriched over the short term in the organic plots after compost incorporation. The relative importance of various environmental variables in governing the composition of microbial communities could be ranked in the order: soil type > time > specific farming operation (e.g., cover crop incorporation or sidedressing with mineral fertilizer) > management system > spatial variation in the field. Measures of the microbial community and soil properties (including microbial biomass carbon and nitrogen, substrate induced respiration, basal respiration, potentially mineralizable nitrogen, soil nitrate and ammonium, and soil moisture) were seldom associated with the variation in the PLFA profiles.

Climatic effect on alfalfa dry matter production. Part I. Spring Harvest

Research on isolated populations of common wall lizard Podarcis muralis (Laurenti, 1768) (Reptilia) from Dobrogea (Romania and Bulgaria) The isolated populations of common wall lizard Podarcis muralis from Dobrogea are strictly located in a few rocky habitats situated in the southern area of this geographical province. The sizes of these populations are small, compared to the populations from the rest of the area occupied by the species. This aspect, together with their strict location, makes them suitable for complex population studies. The work hypothesis was that the common wall lizard populations in Dobrogea are not connected to those from the Carpathians, the Danube and the Romanian Plain being bio-geographical barriers. In light of this hypothesis, the colonization of Dobrogea by the common wall lizard occurred from the south with individuals coming from populations located in the Balkan Peninsula.

The potential influence of predators on lacertid lizards has been studied by using models made of plasticine which shows the attack marks of predators and as such allows their identification and estimation of predation pressure. The general aim was to study predation on plasticine models of lizards and to improve methods, since the results depend on the number of plasticine models used, their spatial pattern and the duration of experiments. We estimated the density of the common wall lizard Podarcis muralis population on stone walls of a vineyard in the city of Pecs (Hungary) in August 2015 in order to imitate the real density in our experiment with plasticine models. The density of common wall lizards was 8.2 ind. /100 m 2 and accordingly we placed 25 scentless plasticine lizards on the stone walls on the first transect with 10 m distance between them, which imitates the real pattern. In the second transect 25 lizard models were placed more sparsely, the distance between them being 20 m. During four weeks the predation rate was 24% in densely spaced plasticine lizards and 40% in sparsely spaced plasticine lizards, but the difference was not significant. The daily survival rate of densely spaced lizards was 0.99 (=99.1%) and that of sparsely spaced lizard models was 0.98 (=98.25%), but this difference was not significant either. On the basis of marks left on plasticine lizards, mammal predators (e.g. beech marten) dominated, while the impact of bird predators was smaller than expected. Predators attacked the head of plasticine lizards more frequently than their trunk, tail or limbs, but a significant preference of body parts was not detected. From our experience it is important to study the distribution and density of real animals, to imitate their real pattern, instead of an arbitrarily designed experiment with models. The typical scent of plasticine also could influence the results, which can be avoided by using scentless plasticine models coated with liquid rubber. We suggest the calculation of daily survival rates in order to produce results that allow the comparison of different studies.

BackgroundNeural crest cells (NCCs) are migratory embryonic stem cells that give rise to a diverse set of cell types. Here we describe the dynamic distribution of NCCs in developing embryos of the common wall lizard Podarcis muralis inferred from 10 markers. Our aim is to provide insights into the NCC development of lacertid lizards and to infer evolutionary modifications by comparisons to other tetrapods.ResultsNCC migration is ongoing at oviposition, following three streams in the head and multiple in the trunk. From 21ss, we observe expression patterns indicating the beginning of differentiation toward mesenchymal and neuronal fates. By 35ss, migration is restricted to caudal levels, and fully differentiated chromaffin cells are observed.ConclusionsWe find that some markers show patterns that differ from other tetrapods. For example, the antibody HNK‐1 labels three NCC streams from the hindbrain while some comparable reptile studies describe four. However, the information emerging from all markers combined shows that the overall spatiotemporal distribution of NCCs in the common wall lizard is largely conserved with that of other tetrapods. Our study highlights the dynamic nature of seemingly canonical marker genes and provides the first description of spatiotemporal NCC dynamics in a lacertid lizard.

The lacertid wall lizards of the genus Podarcis (Wagler, 1830) originate from Western Europe and are divided into 24-25 species (Speybroeck et al., 2020). Despite the abundance of phylogenetic studies referring to the genus, the relationships among certain species, as well as the taxonomic status of some genealogical lineages, remain unclear due to great genetic diversity. The common wall lizard Podarcis muralis has a relatively wide distribution and despite the existence of various molecular studies focused on this species, its Greek populations had never been thoroughly sampled until now. To fill in this geographical gap, we sampled the species’ Greek distribution and constructed phylogenies that uncovered the presence of at least five monophyletic lineages that correspond to different geographic regions. Furthermore, species delimitation analyses assigned all lineages to a single species diversifying during the early Pleistocene (c. 1.93 mya). The strong association of the genetic lineages with specific geographical regions coupled with the Pleistocene diversification of the group imply the presence of multiple refugia within Greece and, by extension, the Balkan peninsula, supporting a refugia-within-refugia scenario. Finally, in an effort to clarify the position of these new samples within the larger phylogeny of P. muralis, a larger phylogeny was constructed which indicated that the Greek populations cluster with the central European, Italian and Turkish populations of the species.

The relative importance of environmental variables for Spartina alterniflora distribution was investigated across different spatial scales using maximum entropy modelling (MaxEnt), a species distribution modelling technique. The results showed that elevation was the most important predictor for species presence at each scale. Mean diurnal temperature range and isothermality were the second most important predictors at national and regional scales respectively. Soil drainage class, pH and organic carbon were important on the northern Chinese coast. The importance of climatic variable type was highest at global and national scales and declined as the scale decreased. The importance of soil variable type was lower at coarser scales, but varied greatly at finer scales. The relationships between environmental variables and species presence changed as the variables’ ranges changed across different scales. Climatic and soil variables were substantially affected by interactions among variables, which changed their relationships with species presence and relative importance. The modelled suitable area on the Chinese coast decreased from 54.16 to 12.64% limited by elevation from the global to national scale, and decreased to 8.04% limited by soil drainage, pH and organic carbon from the national to regional scale. The findings of the present study emphasise the importance of spatial scale for understanding relationships between environmental variables and the presence of S. alterniflora.

Relative Importance of Environmental Variables for Spawning Cues and Tributary Use by an Adfluvial Lake Sucker

Female common wall lizards (Podarcis muralis ) typically reproduce annu- ally and lay more than one clutch per season. In this study, we tested whether females store sperm between clutches and between years by manipulating mating opportuni - ties of females through appropriate experiments. Our results revealed that females are definitely unable to store sperm for medium or long-term, suggesting they necessary need to repeatedly mate with males to fertilize their eggs. Finally, by comparing our results to other similar multi-clutched species, we conclude that sperm storage prob- ably does not constitute a selective advantage for species with a promiscuous repro- ductive system based on multiple mating in populations with high densities.

The likelihood that females will breed or how much they invest in reproduction can depend on the characters of their male partners. Such differential allocation may enhance or limit gene flow between hybridizing lineages, in particular when the lineages have diverged in sexually selected characters. Populations of the common wall lizard (Podarcis muralis) in some regions of Italy exhibit striking exaggeration of coloration, morphology and behaviour compared to populations in France. The two forms hybridize in north-western Italy. Gene flow is directional and in concordance with the prediction that the exaggerated sexual characters of lizards of Italian origin give them a mating advantage. To evaluate if differential allocation contributes to asymmetric introgression, we tested experimentally if female reproductive investment is affected by male origin and male secondary sexual characters. Despite the large genetic and phenotypic divergence between males of Italian and French origin, females did not invest more when paired with males of the same origin, nor when paired with males with highly expressed sexual characters. Combined, these results suggest that female responses to male phenotypes in wall lizards are unimportant for explaining the directional pattern of gene flow in regions of secondary contact.

Understanding variability in the composition of aquatic assemblages requires a multiscale perspective, since processes operating at different spatial scales (from regional to local) drive the community assembly. Here, the relative importance of environmental variables on fish species composition in streams of the Brazilian savanna (Cerrado) is assessed and quantified at local and landscape scales. The importance of both local and landscape environmental variables in structuring fish assemblages was supported. Local variables explained a substantially higher amount of variance of fish assemblages than landscape variables. However, the shared explanation indicate that landscape variables had a complementary effect. The streams sampled were mostly headwaters at similar altitudes and with similar watershed sizes, so the sensitivity of the fish assemblages, even to small landscape gradients, is highlighted. Maintaining these important instream habitat characteristics close to natural conditions seems to be essential for conserving stream fish species, and for this, the landscape context should be taken into account. Considering the near‐pristine condition of the streams studied, these findings can be used as a reference for further studies addressing the effects of human modifications on stream fish biodiversity of the Cerrado.

Since the 1990s, cases of canine leishmaniasis (CanL) due to Leishmania infantum have risen in northern Italy due to dog translocation and movement as well as for climate-driven sand fly population growth. In this geographical region, for a long time regarded as non-endemic for CanL, L. infantum is generally transmitted by the sand flies of the genus Phlebotomus. Other sand flies, such as Sergentomyia minuta, have been less investigated, also because they were only considered as vectors of the nonpathogenic herpetophilic Leishmania tarentolae. Our study investigates sand fly species composition and Leishmania spp. prevalence in hilly areas of northern Italy, in the Bergamo district. Sand flies were sampled with both sticky and light traps. Common wall lizards Podarcis muralis have been captured in the same areas, for the collection of biological samples: blood, feces, tissues, and gut-associated secretions. Sand flies were identified morphologically (males) and molecularly (females). The collected samples were tested for the presence of Leishmania spp. via conventional and digital droplet PCR. Our study reports the presence of Phlebotomus perniciosus, Phlebotomus neglectus, and S. minuta in the investigated area. We report the first detection of L. tarentolae, a Sauroleishmania species, in northern Italy, in both sand fly vectors (S. minuta, P. perniciosus, and P. neglectus) and reptile hosts. Additionally, L. infantum DNA was detected, for the first time, in sand flies and reptiles in the district, spatially overlapping with previously reported local CanL cases. Our study reported the presence of three sand fly species in the Bergamo district, a Sauroleishmania species (the first record in northern Italy), and the occurrence of L. infantum. We emphasize the importance of including both S. minuta sand flies and synanthropic reptiles in leishmaniasis screenings for a better understanding of the epidemiology of the disease.

Theoretical models predict that the outcome of dyadic agonistic encounters between males is influenced by resource-holding potential, resource value, and intrinsic aggressiveness of contestants. Moreover, in territorial disputes residents enjoy a further obvious competitive advantage from the residency itself, owing to the intimate familiarity with their territory. Costs of physical combats are, however, dramatically high in many instances. Thus, signals reliably reflecting fighting ability of the opponents could easily evolve in order to reduce these costs. For example, variation in color morph in polymorphic species has been associated with dominance in several case studies. In this study, we staged asymmetric resident-intruder encounters in males of the common wall lizard Podarcis muralis, a species showing three discrete morphs (white, yellow, and red) to investigate the effects of asymmetries in color morph, residency, and size between contestants on the outcome of territorial contests. We collected aggression data by presenting each resident male with three intruders of different color morph, in three consecutive tests conducted in different days, and videotaping their interactions. The results showed that simple rules such as residency and body size differences could determine the outcome of agonistic interactions: residents were more aggressive than intruders, and larger males were competitively superior to smaller males. However, we did not find any effect of color on male aggression or fighting success, suggesting that color polymorphism in this species is not a signal of status or fighting ability in intermale conflicts.

Introduced species can provide valuable opportunities for applied research once they have become established with little possibility of eradication. They have been used as indicators of environmental contamination in aquatic ecosystems for many years. However, in terrestrial ecosystems, introduced species have not been utilized as sentinels of environmental quality. We review the feasibility of using species of lizards that have been introduced, are closely related to species that have been introduced, or have the potential of being introduced to the United States, as indicators of heavy metal contamination. Metal concentrations in lizards were compared from the few available studies, including one recently conducted on the introduced brown anole Anolis sagrei in southern Florida. Brown anoles, tropical house geckos Hemidactylus mabouia, sand lizardsLacerta agilis, common viviparous lizards Lacerta vivipara, common wall lizards Podarcis muralis, and starred agamas Laudakia (Agama) stellio stellio were shown to be suitable indicators of heavy metal pollution because differences were found in metal levels in lizards from different locations within a given region, and lizards from sites presumed to be contaminated by heavy metals contained higher metal concentrations than those from locations that were uncontaminated.