Biology subjects

Canestrelli, D.

Publications and source records attributed to Canestrelli, D..

At least 19 recordsLinked to original sources

bioRxiv2026

Chromosome-level genome assembly of the European leaf-toed gecko, Euleptes europaea

The European leaf-toed gecko (Euleptes europaea) is a small, nocturnal gecko endemic to the western Mediterranean. As a phylogenetically distinctive member of the Gondwanan family Sphaerodactylidae, it represents an important species for studying Mediterranean island biogeography, adaptation, and reptile genome evolution. The species also occupies a key position for investigating the evolution of sex chromosomes, as geckos exhibit remarkable diversity and frequent transitions in sex-determination systems. We present a chromosome-level genome assembly of Euleptes europaea generated as part of the Vertebrate Genomes Project. The 1.8 Gb assembly has a scaffold N50 of 102.3 Mb (contig N50 27 Mb), with 21 chromosome-scale scaffolds corresponding to the known karyotype (2n = 42). The primary assembly has a BUSCO completeness of 97.80% (95.60% as single-copy), a k-mer completeness of 96.00%, and a k-mer quality value (QV) of 61.20. Repetitive elements account for 53.20% of the genome and genome annotation identified 18,633 protein-coding genes. This high-quality reference genome will facilitate studies of genome evolution, island adaptation, and sex chromosome evolution across geckos and other reptiles.

genomics↗

bioRxiv2026

Fiat lux: A hotspot of Luciola fireflies on Western Mediterranean islands

O_LIIslands are priority areas for the study and conservation of biodiversity, as they frequently harbour distinct lineages. Yet they are particularly threatened by the global change. In the frame of an accelerated biodiversity crisis, many insular species risk disappearing before they are even discovered. C_LIO_LIFireflies, despite their ecological and cultural significance, remain poorly investigated, especially in temperate regions, where they have shown marked decline over the last decades. C_LIO_LIWe investigated firefly diversity across a Mediterranean biodiversity hotspot by genotyping 114 fireflies of the genus Luciola from 29 locations across the Tuscan Archipelago and the adjacent Italian peninsula and applied phylogenetic and species delimitation methods to characterise genetic differentiation and its geographic structure. C_LIO_LIWe found an unexpectedly high level of genetic differentiation in this area. Phylogenetic inference recovered six deeply divergent and geographically structured mitochondrial lineages: three restricted to Elba Island and three to the Italian Peninsula. Genetic divergence among these lineages ranged from 1.97% to 4.58%, values comparable to or exceeding those typically observed among distinct species. Accordingly, species delimitation methods consistently supported their status as distinct species. C_LIO_LIThe coexistence of three divergent lineages on Elba Island suggests a biogeographic scenario characterised by ancient island colonisations and possible in situ diversification. These findings reveal a previously unrecognised depth of evolutionary diversity in Italian fireflies and identify the Tuscan Archipelago as a priority area for future research on firefly evolution and conservation, emphasizing that fireflies are a major gap in our knowledge of insect biodiversity in Europe. C_LI

ecology↗

bioRxiv2024

Can reproductive interference be integrated into the Sterile Insect Technique for pest control? Insights from the spotted wing fly Drosophila suzukii

BACKGROUNDReproductive interference (i.e., sexual interaction between males of one species and females of another species that reduce the fitness of one or both the interacting individuals) is an important species interaction significantly affecting population dynamics and persistence. However, its exploitation in pest control remains overlooked. Here, we investigated the possible integration of reproductive interference into the Sterile Insect Technique (SIT) to develop a heterospecific SIT (h-SIT). Under this approach, contrary to the classic SIT, sterile heterospecific males from closely related, non-pest species are released to compete with the pest population for mates. At this aim, we focused on the invasive pest species Drosophila suzukii and used D. melanogaster as the control species. First, we investigated the effect of irradiation on D. melanogaster sterility and longevity. Then, we tested the mating performance of irradiated males and their ability to reduce the D. suzukii fitness. RESULTSWe found by microcosm experiments that: i) irradiation induced high levels of D. melanogaster male sterility without reducing longevity; ii) irradiated D. melanogaster males court D. suzukii females as much as D. suzukii males and they couple, mate and fecund heterospecific females; iii) irradiated D. melanogaster males significantly reduce the offspring of D. suzukii females under two different species ratios. CONCLUSIONSOur results provide the first foundation to develop a heterospecific Sterile Insect Technique against D. suzukii and fuel to test this approach against other groups of pest species.

ecology↗

bioRxiv2024

Adaptation to water salinity changes: phenotypic plasticity meets and moulds carry-over effects in sea rock-pool mosquitoes

Environmental conditions experienced during early-life can shape trait expression after metamorphosis. Direct carry-over effects occur when the value of a trait expressed at an early stage directly determines its expression at later stages, maintaining phenotypic continuity across metamorphosis. However, environmental factors generally affect multiple traits whose interaction might shape developmental trajectories. Here, we tested the hypothesis that trait interactions can shape direct carry-over effects by examining the interplay between behavioural and morphological plasticity in the sea rock-pool mosquito Aedes mariae under varying salinity conditions. We found plastic changes in body size and behaviour. Higher salinity reduced larval body size and increased resting behaviour at the water surface while browsing activity decreased. Under constant conditions, larval body size was positively correlated with pupal size, indicating a direct carry-over effect. However, this relationship was disrupted as salinity increased due to larval size-dependent behavioural plasticity which decouples pupal morphology from larval size. Our results show that environmental conditions modulate trait integration and modify direct carry-over effects. These findings highlight the importance of considering multiple traits when studying developmental plasticity and contribute to the ongoing debate on the extent to which one life stage is coupled to the others across metamorphic boundary.

ecology↗

bioRxiv2024

Behavioural variation in background colour matching and the effect of social environment in rock-pool mosquitoes

Several animal species conceal themselves from potential predators by actively choosing environmental patches that best match body colouration and chromatic patterns. Growing evidence shows that a variety of contexts and conditions can affect this background choice behaviour, yet the extent of this variety remains largely underexplored. Here, we explore the effect of disturbance and social environment on background colour choice behaviour in the rock-pool mosquito Aedes mariae. We exposed single individuals and groups of individuals to experimental arenas made of dark and bright patches, and recorded individuals colour preferences when alone and within groups, as well as before and after a disruptive event. We found a marked prevalence of individuals favouring a dark background and an among-individual variation in choice over replicated trials. Moreover, we observed a non-significant effect of disturbance but a significant role of the social environment. In fact, being caged in groups significantly increased the proportion of mosquitoes choosing the dark background. Our results provide strong evidence of a background colour choice in Ae. mariae, a density-dependence of this choice, and a non-negligible inter-individual variation in this behaviour. Overall, these findings offer intriguing insights into the background choice behavioural variation and flexibility in mosquitoes.

ecology↗

bioRxiv2024

Keeping common species common: the role of future climate refugee in species conservation

Climate change is one of the most important challenges for biodiversity conservation. Species may respond to changing climates by moving, adapting, and/or adjusting. The move response is the easiest and quickest as it does not imply any evolutionary and/or physiological response. However, moving in space to track changing climate is not an option for species with restricted movement capacities (e.g., many amphibians) or species endemic to islands. Therefore, the impact of climate change on these species is potentially dramatic, even when they are currently widespread and least concern. Planning for the conservation of these species in a global change context requires a proactive approach, with the identification of climatic refugia, i.e., areas climatically suitable for a given species under both current climate and future scenarios. Here, we demonstrated our approach considering the Hyla sarda, an amphibian endemic of the islands of Sardinia and Corsica, currently widespread in its range, and Least Concern according to the IUCN Red List. We calibrated an SDM for the species focusing on Sardinia and projected it into the future, identifying all areas that can act as future climatic refugia. We also evaluated the coverage of the refugia by the existing protected areas. According to our results, Hyla sarda will experience a significant restriction of its distribution range due to projected climate changes, with small and highly fragmented climatic refugia mostly located outside of existing protected areas. Our findings highlight the importance of considering common species in global change studies. All our conservation strategies should be more proactive if we want to conserve common species before they become rare.

ecology↗

bioRxiv2024

Predator cues and environmental enrichment during development drive intraspecific variation in the behaviour and life-history of juvenile lobsters

Intraspecific variation in ecologically relevant traits is critical for animal populations to survive in our rapidly changing world. This is especially true for species that suffer from intense harvesting regimes, whereby populations density is often low. Standard hatchery procedures can assist some management and conservation programs by producing large numbers of juveniles to be released into the wild. Yet we know surprisingly little on the impact that such standard, minimalistic settings have on the development of intraspecific variation in important phenotypes of the individuals, including among-individual variation in behavioural (individuality) and life-history traits, and in the plasticity of those traits in response to varying environmental conditions. Here, we fill this gap by testing whether early-life exposure to different environmental conditions alters the development of individuality and plasticity in ecologically relevant behaviours and life-history traits of the European lobster (Homarus gammarus)--one the most harvested species in the Mediterranean, which has been subjected to conservation programs for decades. By accessing one of the largest lobsters hatcheries in Italy, we used the progeny of wild-caught females and manipulated--in a full factorial design--the environmental complexity of the individual enclosures (i.e. presence/absence of substrate and/or shelter) and the level of exposure to cues from their natural predators. We repeatedly quantified behaviours (i.e. activity, refuge use, and aggressiveness) and life-history traits (i.e. carapace length and intermoult period) of the individuals throughout their early development, capturing both mean and individual-level variation across treatments. Our results offer solid evidence that effects of standard hatchery settings extend far beyond mean changes in the behaviour and life history of the animals, compromising the development of individual plasticity in those traits that are essentials for populations to survive in the wild--likely reducing the effectiveness of conservation programs.

animal behavior and cognition↗

bioRxiv2022

Behavioural foundation of a massive mitochondrial introgression in the fire salamander, Salamandra salamandra

Patterns of mito-nuclear discordance across secondary contact zones have been reported in a wide range of animal and plant organisms. They consist of a spatial mismatch between nuclear and mitochondrial genomes, in terms of the geographic location and/or extension of the secondary contact zone between distinct evolutionary lineages. Several theoretical and empirical studies have identified massive mitochondrial introgression as the putative source of these mismatches. Yet, we still lack a clear understanding of the potential phenotypic underpinnings of these instances of massive introgression. In this study, we addressed the hypothesis that mtDNA variation across a contact zone could be associated with variation at phenotypic traits affecting dispersal propensity. We analyzed patterns of behavioural and genetic variation across a mtDNA secondary contact zone of the fire salamander Salamandra salamandra in central Italy, which is over 600 km displaced from its nuclear counterpart. We found distinct behavioral profiles associated with the two mitotypes co-occurring in the mtDNA secondary contact zone. Counterintuitively, we found a slow-thorough dispersal profile associated with the massively introgressed mitotype. This dispersal profile was characterized by shy, less active and less exploratory personality traits, and this pattern was consistent across life-stages and contexts (i.e., aquatic larvae and terrestrial juveniles). Our results provide experimental evidence supporting the intriguing hypothesis that personality traits associated with distinct mitotypes could promote differential mitochondrial introgression within alternative nuclear backgrounds.

evolutionary biology↗

bioRxiv2022

Brain de novo transcriptome assembly of a toad species showing polymorphic anti-predatory behavior

Understanding the genomic underpinnings of antipredatory behaviors is a hot topic in eco-evolutionary research. Yellow-bellied toad of the genus Bombina are textbook examples of the deimatic display, a time-structured behavior aimed at startling predators. Here, we generated the first de novo brain transcriptome of the Apennine yellow-bellied toad Bombina pachypus, a species showing inter-individual variation in the deimatic display. Through Rna-Seq experiments on a set of individuals showing distinct behavioral phenotypes, we generated 316,329,573 reads, which were assembled and annotated. The high-quality assembly was confirmed by assembly validators and by aligning the contigs against the de novo transcriptome with a mapping percentage higher than 91.0%. The homology annotation with DIAMOND (blastx) led to 77,391 contigs annotated on Nr, Swiss Prot and TrEMBL, whereas the domain and site protein prediction made with InterProScan led to 4747 GO-annotated and 1025 KEGG-annotated contigs. The B. pachypus transcriptome described here will be a valuable resource for further studies on the genomic underpinnings of behavioral variation in amphibians.

evolutionary biology↗

bioRxiv2022

Spatial differentiation of background matching strategies along a Late Pleistocene range expansion route

Late Pleistocene climate changes have deeply impacted the range dynamics of temperate species. While the genetic legacy of these dynamics has been widely investigated, little is known about their phenotypic consequences. Anti-predatory strategies offer intriguing opportunities to study phenotypic evolution in response to dispersal dynamics since the ability to avoid predation can be pivotal for populations colonizing new environments. Here we investigated the spatial differentiation of background colour matching strategies along a Late Pleistocene range expansion route of a temperate species, the Tyrrhenian tree frog Hyla sarda. Using common-garden experiments, we investigated whether individuals sampled in the source area (Sardinia) and individuals sampled in the newly founded area (Corsica) differ in two components of the camouflage strategy: colour change abilities and background choice behaviour. We found a remarkable spatial structure in both colour change abilities and background choice behaviour, across the expansion range. Tree frogs from the source area displayed higher colour change abilities and a more pronounced preference for a greener background, with respect to tree frogs from the newly colonized area. We discuss these results in the context of the spatial and demographic components of the expansion dynamics. Our results support the intriguing hypothesis that Late Pleistocene biogeographic history might be an overlooked major player in shaping current spatial patterns of phenotypic traits variation across animal populations.

evolutionary biology↗

bioRxiv2022

First brain de-novo transcriptome of Tyrrenhian tree frog, Hyla sarda, for the study of dispersal-related behavioral variation

Dispersal is a key process in ecology and evolution as it contributes to shaping the spatial patterns of biological diversity at all its levels of organization. Growing evidence is unveiling the role of phenotypic trait variation in affecting dispersal dynamics of populations, and that substantial, rapid, and directional changes in the phenotypic makeup of populations would occur during range expansions by spatial sorting of dispersal-related traits. Accordingly, selective pressures at the front of a range expansion wave would actively promote individuals with higher dispersal abilities. Although many studies have been focusing on phenotypic trait evolution during range expansion, its genomic underpinnings are almost unexplored, hampering a thorough understanding of the evolutionary processes involved during dispersal. The Tyrrhenian tree frog Hyla sarda is a small amphibian endemic to the Tyrrhenian islands. According to previous phylogeographic studies, H. sarda underwent a northward range expansion from the north of Sardinia (western Mediterranean sea) during the last glacial phase. The colonization of the Corsica island was allowed by the temporary formation of a wide land bridge connecting Sardinia and Corsica, induced by the marine regression occurred during the last glacial maximum. The postglacial loss of this land bridge prevented any subsequent gene flow between Corsican and Sardinian populations. As a consequence, the genetic and phenotypic legacies of this range expansion event can still be detected in current populations, which makes H. sarda an interesting candidate species for the study of the genetic underpinnings of phenotypic trait evolution during range expansions. Here, we contribute to the investigation of the genetic underpinning phenotypic trait evolution during range expansion, by generating the first brain de-novo transcriptome of H. sarda. We focused on the brain transcriptome as behavioural variation at personality traits has been identified as a key component of the dispersal syndromes, substantial personality traits variation has been observed within H. sarda populations, and brain gene expression patterns have been linked to a vast number of behavioural responses to environmental stimuli.

evolutionary biology↗

bioRxiv2022

Evolution of personality and locomotory performance traits during a late Pleistocene island colonization in a treefrog

Recent empirical and theoretical studies suggest that personality and locomotory performance traits are crucial components of the dispersal syndromes, and that they can evolve during a dispersal process. Island colonisation is one the best characterized processes in dispersal biogeography, and its implication in the evolution of phenotypic traits has been investigated over a wide range of temporal scales. However, the effect of island colonization on personality and performance traits of natural populations has been little explored, and no studies have addressed these processes in the context of late-Pleistocene range expansions. Here, we investigated the contribution of island colonisations triggered by post-glacial range expansions to intraspecific variation in personality and locomotory performance traits. We compared boldness, exploration, jumping performance, and stickiness abilities, in three equidistant populations of the Tyrrhenian tree frog Hyla sarda, two from the source area and one from the colonised island. Individuals from the colonised population were significantly bolder than individuals from the source area, as they emerged sooner from a shelter (p=0.028), while individuals from the source area showed markedly higher jumping and stickiness performance (both p<0.001). We discuss these results in the context of the major microevolutionary processes at play during range expansion, including selection, spatial sorting, and founder effects. However, irrespective of the processes contributing the most, our results clearly indicate that late Pleistocene climatic changes have had major consequences not just on species range dynamics, but also on the spatial patterns of phenotypic variation within species, including personality and locomotory traits variation.

evolutionary biology↗

bioRxiv2022

Shock or jump: deimatic behaviour is repeatable and polymorphic in a yellow-bellied toad

Inter-individual variation in antipredatory strategies has long attracted curiosity among scientists. Deimatisms is a complex and time-structured antipredatory strategy consisting in prey suddenly unleashing unexpected defences to frighten predators and stop their attack. Being deimatism traditionally considered as a stereotyped antipredatory response, the inter-individual variation in phenotypic traits related to deimatic displays is almost unexplored. In this study, we employed common garden experiments on 71 yellow-bellied toad Bombina pachypus to investigate the extent and pattern of inter-individual variation in the unken-reflex behaviour, a deimatic display performed by some amphibians. Results show that deimatic displays consistently differ among individuals. Only about half of the individuals reacted to the predation stimuli by exhibiting the display, which varied in responsiveness, duration and intensity. All the investigated descriptors were repeatable (R > 0.50, p < 0.01). Finally, we found significant correlations between the measured parameters, defining two alternative behavioural profiles: individuals quickly doing unken-reflex, with high intensity and long duration of the display, and individuals avoiding unken-reflex but rather escaping. Such dichotomy resembles respectively the proactive and reactive coping styles. Such an unexpected variation in deimatic behaviour raises intriguing questions on the evolutionary processes shaping multiple adaptive responses to predation within populations.

ecology↗

bioRxiv2021

From STRs to SNPs via ddRAD-seq: geographic assignment of confiscated tortoises at reduced costs

Assigning individuals to their source populations is crucial for conservation research, especially for endangered species threatened by illegal trade and translocations. Genetic assignment can be achieved with different types of molecular markers, but technical advantages and cost saving are recently promoting the shift from short tandem repeats (STRs) to single nucleotide polymorphisms (SNPs). Here, we designed, developed, and tested a small panel of SNPs for cost-effective geographic assignment of individuals with unknown origin of the endangered Mediterranean tortoise Testudo hermanni. We started by performing a ddRAD-seq experiment on 70 wild individuals of T. hermanni from 38 locations. Results obtained using 3,182 SNPs are comparable to those previously obtained using STR markers in terms of genetic structure and power to identify the macro-area of origin. However, our SNPs revealed further insights into the substructure in Western populations, especially in Southern Italy. A small panel of highly informative SNPs was then selected and tested by genotyping 190 individuals using the KASP genotyping chemistry. All the samples from wild populations of known geographic origin were genetically re-assigned with high accuracy to the original population. This reduced SNPs panel represents an efficient molecular tool that enables individuals to be genotyped at low cost (less than {euro}15 per sample) for geographical assignment and identification of hybrids. This information is crucial for the management in-situ of confiscated animals and their possible re-allocation in the wild. Our methodological pipeline can easily be extended to other species.

genomics↗

bioRxiv2020

Paso doble: A two-step Late Pleistocene range expansion in the Tyrrhenian tree frog Hyla sarda

The Tyrrhenian tree frog, Hyla sarda, is an amphibian endemic to the Tyrrhenian islands (Western Mediterranean). Previous investigations of its Pleistocene evolutionary history suggested that it colonised the northern portion of its current range, through a spatial diffusion process from the Sardinia island, during the last glaciation. However, southern and northern portions of the species range experienced markedly different climatic conditions during the Late Pleistocene, suggesting the possibility of an unusual two-step process of demographic expansion. Here, we use Bayesian phylogeographic approaches to locate the ancestral area in Sardinia and to characterise better the demographic component of this expansion event. These analyses located the ancestral area for H. sarda populations along the central-eastern coast of the Sardinia island, within an area previously shown to host suitable bioclimatic conditions for H. sarda populations throughout the Late Pleistocene. Historical demographic reconstructions clearly showed that a two-step process of demographic growth fits well the data, with northern populations expanding later than Sardinia populations. The harsher climatic conditions occurred in northern islands during the glacial epoch, as compared to Sardinia, likely delayed tree frog colonisation of northern territories, and the associated demographic growth.

evolutionary biology↗

bioRxiv2019

Environmental correlates of the European common toad hybrid zone

The interplay between intrinsic (development, physiology, behavior) and extrinsic (landscape features, climate) factors determines the outcome of admixture processes in hybrid zones, in a continuum from complete genetic merger to full reproductive isolation. Here we assess the role of environmental correlates in shaping admixture patterns in the long hybrid zone formed by the toads Bufo bufo and B. spinosus in western Europe. We used species-specific diagnostic SNP markers to genotype 6584 individuals from 514 localities to describe the contact zone and tested for association with topographic, bioclimatic and land use variables. Variables related to temperature and precipitation contributed to accurately predict the distribution of pure populations of each species, but the models did not perform well in areas where genetically admixed populations occur. A sliding window approach proved useful to identify different sets of variables that are important in different sections of this long and heterogeneous hybrid zone, and offers good potential to predict the fate of moving contact zones in global change scenarios.

evolutionary biology↗

bioRxiv2019

Unveiling cryptic diversity among Mullerian co-mimics: insights from the Western Palaearctic Syntomis moths (Lepidoptera: Erebidae)

Accurate species delimitation is of primary importance in biodiversity assessments and in reconstructing patterns and processes in the diversification of life. However, the discovery of cryptic species in virtually all taxonomic groups unveiled major gaps in our knowledge of biodiversity. Mimicry complexes are good candidates to source for cryptic species. Indeed, members of mimicry complexes undergo selective pressures on their habitus, which results in strong resemblance between both distantly and closely related species. In this study, we used a multi-locus genetic approach to investigate the presence of cryptic diversity within a group of mimetic day-flying moths whose systematics has long been controversial, the Euro-Anatolian Syntomis. Results showed incongruence between species boundaries and currently accepted taxonomy of the group. Both mitochondrial and nuclear markers indicate presence of four, well-distinct genetic lineages. The genetic distance and time of divergence between the Balkan and Italian populations of S. marjana are the same as those found between S. phegea and S. ragazzii, the last two being well-distinct, broadly sympatrically occurring species. The divergence between the two lineages of S. marjana dates back to the Early Pleistocene, which coincided with substantial changes in climatic conditions and vegetation cover in Southern Europe that have likely induced geographic and ecological vicariance. Our results show that the species richness of mimicry complexes inhabiting temperate regions might still be severely underestimated. Syntomis populations up to now designated as S. marjana albionica, S. m. quercii and S. marjana kruegeri s. str. are here considered to represent a separate species from nominate marjana and are distinguished as Syntomis quercii Verity, 1914, bona sp., stat. nov.

zoology↗

bioRxiv2018

Who’s who in the western Hermann’s tortoise conservation: a STR toolkit and reference database for wildlife forensic genetic analyses

Illegal trade is threatening tortoise populations worldwide since decades. Nowadays, however, DNA typing and forensic genetic approaches allow to investigate geographic origin of confiscated animals and to relocate them into the wild, provided that suitable molecular tools and reference data are available. Here we assess the suitability of a small panel of microsatellite markers to investigate patterns of illegal translocations and to assist forensic genetic applications in the endangered Mediterranean land tortoise Testudo hermanni hermanni. We used the microsatellite panel to (i) increase the understanding of the population genetic structure in wild populations with new data from previously unsampled geographic areas (overall 461 wild individuals from 28 sampling sites); (ii) detect the presence of non-native individuals in wild populations; and (iii) identify the most likely geographic area of origin of 458 confiscated individuals hosted in Italian seizure and recovery centers. Our analysis initially identified six major genetic clusters corresponding to different geographic macro-areas along the Mediterranean range. Long-distance migrants among wild populations, due to translocations, were found and removed from the reference database. Assignment tests allowed us to allocate approximately 70% of confiscated individuals of unknown origin to one of the six Mediterranean macro-areas. Most of the assigned tortoises belonged to the genetic cluster corresponding to the area where the respective captivity center was located. However, we also found evidence of long-distance origin of confiscated individuals, especially in centers along the Adriatic coast and facing the Balkan regions, a well-known source of illegally traded individuals. Our results clearly show the role for reintroduction projects of the microsatellite panel, which was useful to re-assign most of the confiscated individuals to the respective macro-area of origin. At the same time, the microsatellite panel can assist future forensic genetic applications to detect illegal trade and possess of Testudo hermanni individuals.

genetics↗