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Le pressioni selettive che agiscono sulle popolazioni insulari sono spesso differenti da quelle esistenti sulla terraferma, tendendo a diversificare gli animali che vivono in questi ambienti. Tali variazioni sono state ampiamente descritte per molti animali e piante, e possono essere inquadrate in almeno tre modalità dette sindromi o regole. La Regola Insulare, evidenzia il gigantismo nei mammiferi piccoli e il nanismo in quelli grandi. La Sindrome Insulare (IS) descrive la ridotta aggressività, il gigantismo, la riduzione nella dimensione della prole e il ritardo nella maturità sessuale. Infine, la Sindrome Insulare Inversa (RIS) descritta solo per la lucertola campestre, pone al centro dell’adattamento insulare gli adattamenti che favoriscono il rapido trasferimento del contributo genetico alle generazioni successive (Raia et al., 2010). Tra le condizioni necessarie al manifestarsi della RIS sembrerebbero necessarie l’instabilità ambientale e la scarsa aspettativa di vita da parte delle popolazioni animali. In questa ricerca si è cercato di svelare le basi genetiche della RIS e le implicazioni temporali che sono necessarie allo sviluppo degli adattamenti fenotipici (Monti et al., 2013). Lo studio è stato condotto su tre popolazioni che potevano rappresentare: la condizione wild-type (le lucertole della terraferma Punta Campanella), la condizione insulare senza evidenze di sindrome (le lucertole dell’isola di Capri) e la condizione insulare in cui erano evidenti i segnali della sindrome (le lucertole del faraglione Scopolo, a largo di Capri, noto anche come faraglione di Fuori). Come marcatori di sindrome sono stati esaminati la larghezza del capo, il grado di melanizzazione della pelle e il comportamento aggressivo. Per ognuno degli ambienti che ospitavano le tre popolazioni sono state studiate le pressioni selettive, considerando la pressione predatoria e il carico parassitario cutaneo. Le lucertole di Scopolo hanno un capo più largo, sono più aggressive e sono caratterizzate da un forte melanismo. La validità di questi marker ha reso questo approccio sperimentale un futuro strumento di indagine per investigare la RIS in altre popolazioni insulari. Le pressioni selettive indagate (predazione e carico parassitario) si sono rivelate nettamente più forti su Scopolo rispetto alle altre due aree di studio esaminate. Molto probabilmente queste estreme condizioni ecologiche rappresentano alcune delle spinte adattative alla base dei caratteri riconducibili alla RIS. Il gene per il recettore della melanocortina 1 (MC1R), responsabile dei processi di melanizzazione nei lacertidi insulari (Fulgione et al., 2015), si esprime differentemente nelle tre popolazioni, mostrando un forte incremento di mRNA in quella di Scopolo. Il mitogenoma è stato assemblato per approfondire eventuali variazioni tra le tre popolazioni, in termini di modalità di mutazione. Per questo marcatore, la popolazione sotto sindrome (Scopolo) evidenzia un basso numero di mutazioni nelle regioni codificanti, principalmente di tipo neutrale. Tutte queste evidenze hanno suggerito che la variazione mostrata dai fenotipi sotto sindrome può dipendere da un set di geni differentemente espressi piuttosto che da mutazioni a livello genico. Per indagare la veridicità di questa ipotesi è stata allestita un’analisi trascrittomica su due organi principalmente implicati nei caratteri fenotipici della sindrome, i testicoli e il cervello. L’elaborazione del trascrittoma mediante tecnologia de novo utilizzando più tessuti, è stata effettuata per la popolazione insulare (Scopolo) e per quella della terraferma (Punta Campanella). L’analisi trascrittomica ha rilevato un basso numero di SNPs nelle regioni codificanti e una maggiore espressione di molti geni legati alla RIS nella popolazione di Scopolo, dimostrando ancora una volta che la modalità regolativa può essere alla base delle variazioni osservate. Una sostanziale differenza nelle variazioni imputabili alla regolazione/metilazione del DNA piuttosto che alla modifica del genoma, sta nei tempi in cui è possibile attuare questi cambiamenti. Lucertole insulari sottoposte a forti pressioni selettive, possono rispondere attraverso la regolazione in tempi brevi e con adattamenti specifici. E’ stato quindi deciso di stimare i tempi di divergenza delle tre popolazioni e in particolare di Scopolo, la popolazione sotto sindrome. Utilizzando il genoma mitocondriale come molecular clock, è risultato evidente che la quantità di mutazioni nel mtDNA delle lucertole di Capri è proporzionata ai tempi di separazione di Capri dalla terraferma. Differentemente, la quantità di mutazioni accumulate sul genoma mitocondriale della popolazione di Scopolo è sensibilmente inferiore a quella attesa rispetto ai tempi di separazione del faraglione (Scopolo) dalla sua terraferma (isola di Capri). Questi dati confermano l’ipotesi che il genoma dei lacertidi della popolazione sotto sindrome (Scopolo) non ha subito sostanziali cambiamenti strutturali a fronte di una forte variazione fenotipica. Quest’ultima sarebbe il frutto di una regolazione genica che potrebbe dipendere da diversi fattori trascrizionali o dalla metilazione del DNA. Questa ricerca se da un lato ha aggiunto informazioni circa i modi e i tempi evolutivi del nostro caso di studio, dall’altro lato ha aperto numerosi spunti di indagine che riguardano appunto i meccanismi genetici alla base della strategia regolativa.

After the Second World War, agro - pastoral practices in Italian mountain areas were progressively abandoned due to the development of industry and intensive crop. Human depopulation of rural mountain areas and the consequent abandonment of traditional land management are among the greatest driving forces behind changes in this ecosystem in whole Western Europe. This change involves a specific ecological succession, in which grassland gradually turns into scrubland and, ultimately, into forest, increasing in agro - pastoral landscape fragmentation, reducing patches size and increasing in mutual distance. The animal associated with agro - pastoral habitat may suffer from decreased connectivity as a consequence. The Rock Partridge ( Alectoris graeca ) is a mountain species endemic to Europe here used as a model for investigating the impact of habitat loss, fragmentation, hunting and climate change. We compared the habitat suitability of the Apennine Rock Partridge prior to abandonment of traditional agro - pastoral activities with the current landscape, in order to investigate the effect of secondary succession on the distribution and v iability of the species. We aimed to understand the type and extent of habitat loss that the Apennine population has experienced. We assessed the past landscape throughout historical aerophotography an d species distribution (c. 1900 - 1950) by quantifying anecdotal evidence from interviews. Current landscape and distribution were assessed from GIS resource and survey data respectively. We applied ecological niche factor analysis and connectivity approaches to obtain historical and current Rock Partridge hab itat suitability. Results indicated that in just five decades our study area has experienced profound changes in landscape structure and function. We observed a drastic decrease in connectivity as a result of a reduction in numbers and size of high suitabi lity patches. We suggest to maintain a viable populatio n it requires an ensemble of ecological conditions along corridors connecting the actual residual populations. In the Rock Partridge, we also showed that, during this time period, species experienced a shift of niche and an increase of marginality. However, if the increased population’ s fragmentation recorded since the 1900s persists, the extinction of some of the subpopulations appears inevitable

The Wild Boar (Sus scrofa) is the most-widely distributed ungulate of the world. Since the 1960s, wild boars went through a worldwide population expansion that increased their overall geographic distribution as well as their population density in many areas in Europe. For example studies documented an increase of wild boar hunting bag by 540% during 1960 - 2002 in Northern Germany, meanwhile in France by 500% during the 1973 - 1993, and in the next five years by an additional 900%. The widespread increase in numbers and geographica l range of this species might have a remarkable impact on many plant communities and animal species, habitat structure and crop and livestock production. The Cilento and Vallo di Diano National Park has instituted in the 1995 in the hotspot of Mediterranea n region. From this period the administration of Park has refunded, to the local communities, some of the damage declared for the agricultural or traditional manufacture constructions imputable to wild boar actions. Just at the end of 2009 National Park go vernance started an organic plan to manage the wild boar problem, in collaboration with University of Naples Federico II. Here we report this action plan, arisen from an interdisciplinary approach in consideration of all the components that are associated to this problem. We developed simulation of population dynamics in the national park, as well as to verify the effectiveness of the management operations in progress throughout the action planed. We analysed the population genetic characteristic, in the li ght of European wild boar phylogenesis and human translocation, hybridization with the domestic form and their effect on the wild populations. We evaluated also population structure arising from this overpopulation. The lack of natural predators, the eleva ted environmental plasticity, and peculiar reproductive biology of some hybrid populations would seem concomitant causes of the high density both in natural and anthropic areas. Moreover wild boar ecological invasion can create problem to some critical spe cies like as orchids, birds nesting on ground (i.e. Alectoris graeca ) or lizards ( Podarcis sicula ). Wild boar problem involves progressively many protected areas in Italy and the divulgation of a scientific management can represent key factor for an organic approach and a prompt for research in conservation biology.

Habitat fragmentation, caused by expanding of human activities through landscape, has heavy effects on the status of natural populations. It causes: the reduction of total biodiversity, the loss of reactivity of the whole ecosystem, and the increase of ecological distances between populations. During the last decade, the endemic Italian hare (Lepus corsicanus) shows a endangered conservation status due to the fragmentation and scarcity of its populations. Globally, this species is classified as vulnerable due to its variable conservation status across its restricted geographic range. Italian hare decreasing can be also imputable to others different factors: harvest, poaching, and the probable interspecific competition with congeneric European hare (Lepus europaeus, introduced in the last decades by man for hunt). However, the creation of several protected areas in southern and central Italy will help the populations to recover. The goal of our work was provide a descriptive model to explain actual distribution of Italian hare in relation to landscape fragmentation and interaction with sympatric European hare. In order to suggest starting point for management actions in the conservation planning of Italian hare. Cilento and Vallo di Diano National Park is home of the greater population of Italian hare, of peninsula, and here we validated ecological model and populations genetic analysis from two species. Genetic approach can be a good tool to quantify status, probable hybridisation, and dispersal, especially if it can be correlated with the connectivity of the landscape. The results suggest that the Italian hare shows an ecological requirement close to average of available resources in the considered landscape. The genetic structure of this autochthonous species can be explained from habitat suitability pattern, and it highlights the differences between the two species. By our first results we can not exclude the inter specific hybridisation events. A lot of conservation actions can be carried out to improve connectivity between Italian hare subpopulations actually characterised by low gene flow: finding new corridors or moving artificially the hare populations.

The Wall Gecko shows heterogeneous colour pattern, which may vary among individuals, depending on the time of day and on the habitat segregation. Nocturnal pale geckos live exclusively on walls. Diurnal dark geckos preferentially live on olive tree trunks, demonstrating an ability to change skin colour that is superior to that of the pale gecko and allows diurnal geckos becoming camouflaged on the diverse substrates occupied during the day. In our study, the nocturnal/pale/wall and diurnal/dark/trunk geckos could be considered the extremes of an ecological cline of morphological variation on which divergent selection may be acting. Combining the effect of balancing selection on nocturnal geckos and disruptive selection between two sympatric populations could lead to speciation. All geckos analysed here belong to the same species, as confirmed by genetic characterization, however diurnal and nocturnal gecko populations seem to be in an early stage of incipient speciation. These two different morphs still combine genes, as revealed by neutral genetic markers, yet they show complete separation according to the analyses of mtDNA coding genes. Experimental results show that diurnal and nocturnal geckos do not swap their niches, likely because the predation pressure causes severe selection for background matching. Genomic analysis of complete mtDNA suggests that nocturnal geckos seem to be under balancing selection perhaps due to the narrow niche in which they live, whereas the daytime population has more opportunity in fitting into the multiple available niches, and they experience positive selection. Here we hypothesize that the ecological segregation that we are witnessing between the nocturnal and diurnal geckos, can lead to a ecological speciation.

Artificial selection affects phenotypes differently by natural selection. Domestic traits, which pass into the wild, are usually negatively selected. Yet, exceptionally, this axiom may fail to apply if genes, from the domestic animals, increase fertility in the wild. We studied a rare case of a wild boar population under the framework of Wright's interdemic selection model, which could explain gene flow between wild boar and pig, both considered as demes. We analysed the MC1R gene and microsatellite neutral loci in 62 pregnant wild boars as markers of hybridization, and we correlated nucleotide mutations on MC1R (which are common in domestic breeds) to litter size, as an evaluation of fitness in wild sow. Regardless of body size and phyletic effects, wild boar sows bearing nonsynonymous MC1R mutations produced larger litters. This directly suggests that artificially selected traits reaching wild populations, through interdemic gene flow, could bypass natural selection if and only if they increase the fitness in the wild.

The Italian hare is endemic to central and southern Italy and currently designated as vulnerable by the International Union for the Conservation of Nature. Despite the worrying status, few studies have explored its ecology. In this scenario, improving knowledge of food preferences is of primary importance. Here, we present a non-invasive pilot study set to analyse the diet composition of the Italian hare from southern Italy, starting from fecal pellets, and using, for the first time on this species, DNA metabarcoding and next generation sequencing. The findings indicated that this approach provides reliable qualitative and semi-quantitative information, allowing the characterization of the hare diet and its seasonal variation using 22 fecal samples. In a single experiment, through time and cost-effective screening of multiple DNA metabarcodes, we detected a broad diversity of plants (99 taxa). Unlike traditional methods, this approach can identify items that leave no solid remains or that simply are lacking in diagnostic taxonomic features. Moreover, it starts from small amounts of input fecal material, useful in investigation on elusive and vulnerable species. The major guideline for future applications is to use a barcode short enough to allow amplification of environmental degraded DNA and the selection of the universal primers for PCR amplification. The results should be useful to define management actions for conservation of endemic Italian hare.

Some insular lizards show a high degree of differentiation from their conspecific mainland populations, like Licosa island lizards, which are described as affected by Reversed Island Syndrome (RIS). In previous works, we demonstrated that some traits of RIS, as melani- zation, depend on a differential expression of gene encoding melanocortin receptors. To better understand the basis of syndrome, and providing raw data for future investigations, we generate the first de novo transcriptome of the Italian wall lizard. Comparing mainland and island transcriptomes, we link differences in life-traits to differential gene expression. Our results, taking together testis and brain sequences, generated 275,310 and 269,885 transcripts, 18,434 and 21,606 proteins in Gene Ontology annotation, for mainland and island respectively. Variant calling analysis identified about the same number of SNPs in island and mainland population. Instead, through a differential gene expression analysis we found some putative genes involved in syndrome more expressed in insular samples like Major Histocompatibility Complex class I, Immunoglobulins, Melanocortin 4 receptor, Neu- ropeptide Y and Proliferating Cell Nuclear Antigen.

Animals recognize their surrounding environments through the sense of smell by detecting thousands of chemical odorants. Wild boars (Sus scrofa) completely depend on their ability to recognize chemical odorants: to detect food, during scavenging and searching partners, during breeding periods and to avoid potential predators. Wild piglets must be prepared for the chemical universe that they will enter after birth, and they show intense neuronal activity in the olfactory mucosa. With this in mind, we investigated the morpho-functional embryonic development of the olfactory mucosa in the wild boar (in five stages before birth). Using mRNA expression analysis of olfactory marker protein and neuropeptide Y, involved in the function of olfactory sensory neurons, we show early activation of the appropriate genes in the wild boar. We hypothesize olfactory pre-birth development in wild boar is highly adaptive.

As largely demonstrated for a wide range of vertebrates, the melanin-based coloration can be the effect of both mutations in the melanocortin-1 receptor (MC1R) gene and of differential expression of the same gene. However, in lizards, this mechanism is poorly known and some populations exhibit a high variation of melanism. Some populations of Podarcis siculus show a gradual melanization, suggesting a case of a quantitative phenomenon rather than a qualitative one. Here, we objectively quantify the continuous colour variation by spectrophotometric analysis demonstrating that the changes in the skin reflectance are not associated to mutations in the coding region of the MC1R gene but seem to be related to a concomitant variation of expression for this gene.

Concealment by means of colour change is a pre-eminent deceptive mechanism used by both predators and prey. The moorish gecko Tarentola mauritanica is able to blend into the background by either darkening or paling according to the substrate darkness. Here we examined the functioning of background perception in moorish gecko. We experimentally excluded the involvement of melanophore-stimulating hormone in camouflage. Blindfolded individuals change their colour consistently with the background. Surprisingly, individuals with covered flanks were not able to change colour, no matter whether they were allowed to see the substrate or not. Accordingly, we found high levels of opsin transcript and protein in the flank region of the gecko. These observations suggest that T. mauritanica skin melanophores are able to activate a process of colour change autonomously. This study yields the first evidence of crypsis mediated by dermal light sensitivity in amniotes.