Marco A.L. Zuffi

Sexual selection drives asymmetric introgression in wall lizards

Hybridisation is increasingly recognised as an important cause of diversification and adaptation. Here, we show how divergence in male secondary sexual characters between two lineages of the common wall lizard (Podarcis muralis) gives rise to strong asymmetries in male competitive ability and mating success, resulting in asymmetric hybridisation upon secondary contact. Combined with no negative effects of hybridisation on survival or reproductive characters in F1-hybrids, these results suggest that introgression should be asymmetric, resulting in the displacement of sexual characters of the sub-dominant lineage. This prediction was confirmed in two types of secondary contact, across a natural contact zone and in two introduced populations. Our study illustrates how divergence in sexually selected traits via male competition can determine the direction and extent of introgression, contributing to geographic patterns of genetic and phenotypic diversity.

Molecular phylogeography of the asp viper Vipera aspis (Linnaeus, 1758) in Italy: evidence for introgressive hybridization and mitochondrial DNA capture

Owing to its temperature dependence and low vagility, the asp viper (Vipera aspis) is an interesting model species to study the effects of Pleistocene climatic fluctuations on vertebrate genomes. We genotyped 102 specimens from the whole Italian distribution range at three mitochondrial DNA regions (2278 characters, total) and six microsatellite DNA loci (Short Tandem Repeats, STR). The molecular phylogeny was constructed according to Bayesian, Neighbour Joining, Maximum Parsimony and Maximum Likelihood procedures. All methods grouped individuals of the three morphological subspecies (V. a. aspis, V. a. francisciredi, V. a. hugyi) into five different haploclades. Specimens assigned to hugyi clustered in two highly differentiated clades, one being sister group to the complex comprising the second clade of hugyi (i.e., a paraphyletic status), plus two clades of francisciredi. The Bayesian clustering of the STR variability disclosed only two groups, the first including aspis and francisciredi, the second all hugyi. Introgressive hybridization and capture of francisciredi-like lineages in the hugyi mitochondrial genome were suggested to explain the discordance between mitochondrial and nuclear data. The phylogeographic pattern was compatible with population contractions in three glacial refuges. Plausibility of derived hypothesis was checked using coalescence simulations as post hoc tests. Long-term drift and serial founder effects, rather than selection, appeared the main factors affecting the genetic make-up of the Italian asp viper.

Schoolchildren and One of the Most Unpopular Animals: Are They Ready to Protect Snakes?

ABSTRACT For cultural reasons and due to the narrow vision of environmental policy makers, most conservation efforts focus on a few charismatic species and consequently neglect the majority of others under threat; many unpopular species are even killed in large numbers with little concern. Redressing this bias through educational programs is therefore important. Snakes are unpopular animals; they suffer from human harassment in most places and many populations have declined worldwide. Consequently, they provide suitable substrate to better improve conservation education in schoolchildren. Responses to a questionnaire administered to 2,570 schoolchildren (7–14 years old) from 10 countries showed that many children liked snakes and that most of the students wanted to see snakes protected. Such counterintuitive results were supported by the explanations given by the children, notably the reasons they liked or disliked snakes. Previous physical contact with snakes was often associated with snake likeability. We also found strong and expected differences between countries: for instance, where venomous snakes represented a health risk, most children declared to be afraid of snakes. Overall, our results negate the simplistic, and previously unverified, adult view that snakes are necessarily perceived as frightening animals, thereby justifying their persecution. This study provides an encouraging message, suggesting that it is not compulsory to focus on charismatic animals to convince children to protect wildlife.

Frequency and effort of reproduction in female Vipera aspis from a southern population

The frequency of reproduction of the asp viper (Vipera aspis, Viperidae) was studied in a population living along the coasts of central Italy. An annual reproductive cycle seemed to be the rule during the 5-year study period. Annual reproduction, high average mass of reproductive females, and large size of neonates, compared with other northern or continental populations, are presumably due to the particularly suitable climatic conditions of the area, as in most coastal habitats of the Mediterranean region. Such a scenario should influence the extent of the feeding period, which allows females, within a few months after parturition, to regain their previous body condition and reproduce again the following year.

Aspects of population ecology of Testudo hermanni hermanni from Asinara Island, NW Sardinia (Italy, Western Mediterranean Sea): preliminary data

Hermanns tortoise ( Testudo hermanni Gmelin) of the Island of Asinara (NW Sardinia, Italy) has been studied during a period of four seasons. This population consisted of several individuals of large body size, some of them being amongst the largest known for this species. Bony shells of males were commonly found on this island, while the same was not true for female bony shells. Although wild boars ( Sus scrofa ) are potential large sized predators for tortoises, the analysis of carapace morphology did not reveal injuries signs due to bites. Male tortoises could die due to up-turning, as the result of male-male combats during the mating season, to possible hyperthermia when upturned, and to predation carried out by birds particularly when upturned. Estimated density was 4.88 individuals ha -1 , which was similar to that of conspecifics from other areas studied so far.

Italian subspecies of the asp viper, Vipera aspis: Patterns of variability and distribution

Abstract The asp viper, Vipera aspis, is distributed in western Europe and comprises several morphological subspecies other than the nominal form, V. a. aspis of northern to southern France: V. a. zinnikeri, V. a. atra, V. a. francisciredi, V. a. hugyi. Each form is very often distinguishable, both by dorsal colour pattern and number of ventral scales. Examining a balanced sample for each subspecies and each sex from Italy and other areas, we found that the distributive patterns of Italian populations are as follows: V. a atra is widely distributed throughout northwestern Italy, reaching the Ligurian Sea coasts; it passes westwards into France up to most of the Haute Provence region, turning northwards up to the Savoie region. Instead, V. a. francisciredi extends eastwards throughout the Po plain and southwards to southern Italy. The distribution limit of V. a. hugyi extends from northern Apulia southwards to the Irpini mountains, and the slopes of Mt. Vesuvius volcano, and the remaining part of Italy and...

Double egg deposition in the European pond turtle, Emys orbicularis, from central Italy.

Abstract The reproductive condition of Emys orbicularis females (presence or absence of oviductal eggs) was studied by palpation and radiography in a coastal population of central Italy (Tuscany). Forty‐nine females were recaptured at least twice during the reproductive period in 1997; 15 of them were found without eggs, 29 reproduced at least once, and 5 reproduced twice. The period of egg retention was estimated to be three to four weeks, and the time between two depositions about 34 days (n = 5). Despite the small sample of females reproducing twice, there is a significant tendency regarding a positive correlation between frequency of reproduction and female body size, within the study population. Reproductive females were bigger than females found without eggs; in addition, carapace length increased significantly in females found zero, one and two times with eggs. A comparison with preliminary data from northern populations of E. orbicularis, lead to the hypothesis that the annual clutch frequency cou...

A critique of the systematic position of the asp viper subspecies Vipera aspis aspis (Linnaeus, 1758), Vipera aspis atra Meisner, 1820, Vipera aspis francisciredi Laurenti, 1768, Vipera aspis hugyi Schinz, 1833 and Vipera aspis zinnikeri Kramer, 1958

External and internal morphology of 415 specimens of the Palaearctic asp viper ( Vipera aspis subspecies and populations), and outgroup taxa ( V. ammodytes , V. berus ), have been examined in order to find patterns of distribution and variation throughout the species range. Within the aspis group V.aspis aspis , V.aspis atra , V. aspis francisciredi , V. aspis hugyi and V. aspis zinnikeri were considered. Ventral scales and number of dorsal bars proved to be the most important external characters to separate populations. Hemipenes showed marked differences between subspecies, in particular in differentiating V. aspis atra , V. aspis hugyi and V. aspis zinnikeri from one another, and also in separating them from the V. aspis aspis — V. aspis francisciredi group. Discriminant Analysis on external features indicated the complete separation of V. aspis atra , V. aspis hugyi and V. aspis zinnikeri and the almost complete overlap of V. aspis aspis and V. aspis francisciredi . The strong morphological differences observed suggest that zinnikeri , atra and hugyi are distinct species, even if further molecular analyses are needed to clarify the whole problem, and neotypes should be designated in order to stabilize taxonomy.

Advances in methodologies of sexing and marking less dimorphic gekkonid lizards: the study case of the Moorish gecko, Tarentola mauritanica

Novelties in systems of sexing and marking less dimorphic species of gekkonid lizards are described and first results are presented on the Moorish gecko, Tarentola mauritanica , used as target and model species. Inspection of cloacal opening and tail basis to detect hemipenes has been done with a small probe and with laser light. Behavioural response to tail basis touch was typical of adult males. Permanent marking has been performed along with the removal of some subdigital scales. Sexing was suitable and feasible on all individuals larger than 45 mm snout to vent length.

Geographic variation of sexual size dimorphism and genetics in the European pond turtle, Emys orbicularis and Emys trinacris, of Italy

We studied the extent of sexual size dimorphism (SSD) in the European pond turtle throughout most of its Italian distribution range using eight morphological parameters of 580 Emys specimens, describing populations from Italy and large Mediterranean islands. Sexual size dimorphism was evident in the whole sample, but not in all the considered areas. SSD in studied Emys likely mirrors different growth trajectories and body size architectures between sexes at adult stage. Italian populations resulted separated into five groups with morphological differences: (i) East Po plain Italy north to Apennines; (ii) Tyrrhenian Italy; (iii) Corse; (iv) Sardinia; and (v) southern Italy and Sicily. These results agree with previously reported data on systematics of Mediterranean populations. Some Italian populations were also tested using restriction endonuclease analysis of 18+28S ribosomal DNA on 43 specimens of eight localities. The occurrence of a restriction fragment length polymorphism of rDNA was also noted. Morphometric and molecular data revealed that the two Calabrian populations were significantly differentiated with respect to the other sampled populations. According to previous mitocondrial DNA analyses, our results also support the view that the southern Italy populations of E. orbicularis are different from other Italian populations, even if our results do not perfectly fit with previous works.