Programma della conferenza

In organisms living in highly variable environments, a strong phenotypic variability within populations is expected due to plastic responses to natural environmental variation. However, this is not commonly observed in nature. Here, we focused on the potential compensatory effects which might arise from the interaction between behavioural and morphological trait plasticity. These traits are remarkably sensitive to environmental conditions, and compelling studies showed that behavioural plasticity can influence individual life history traits such as body size or shape. In microcosm experiments, we manipulated saline concentration and analysed plastic responses in body size, pupal behaviour and carry-over effect across developmental stages in the sea rock-pool mosquito Aedes mariae. Analysing morphological traits, we found that larvae developed under increasing salinity conditions were smaller than larvae developed under constant conditions. Smaller body size at the pupal stage was also observed, testifying the occurrence of carry-over effects from larval to pupal stages. On the contrary, no differences were observed between adult sizes developed under the two salinity conditions. Analysing behavioural traits, we found that higher salinity promoted plastic changes in pupal diving behaviour. Under increased salinity pupae spent 20.6% less time underwater and performed fewer abdominal contractions than pupae under constant conditions. Because pupal energy expenditure is proportional to the time spent underwater, we suggest that the plastic pupal behaviour promoted compensatory growth, breaking down the carry-over effect from the pupal to the adult stage. This study highlights that plasticity at multiple traits in immature stages can affect carry-over and, ultimately, lead to the convergence of the adults' phenotypes.

From a conservation perspective, landscape genomic approaches have been mostly limited to assessing how structural landscape features influence functional connectivity within populations. Here, we explore the potential of landscape genomic data in the context of area-based conservation. Area-based conservation is by far the most successful strategy in addressing the ongoing global biodiversity loss. A key step in this approach is the designation of optimal zoning schemes that effectively integrate biodiversity protection with societal needs. Using restriction site-associated DNA (RAD) sequencing, we investigated the landscape genomic structure of the Italian stream frog Rana italica in the Aspromonte National Park. Population structure analyses revealed a substructure among the southern, central and northern areas of the park. Furthermore, by applying a moving-window approach, we generated maps of genetic diversity that showed higher diversity in the northernmost part of the national park. Surprisingly we found a counterintuitive pattern of lower levels of diversity within strictly than within mildly protected areas of the park. The ongoing study of functional connectivity within the park and its surrounding areas will allow us to understand how natural or artificial landscape elements influence intraspecific biodiversity patterns within and between the zones of the park and to provide fundamental knowledge to improve current zonation scheme.

The loggerhead sea turtle (Caretta caretta) is a globally distributed species and commonly found in the Mediterranean Sea. The main nesting beaches have been described in the Levantine basin, northern Africa and Ionian Sea, however, in the last decade, an increasing number of nesting turtles of unknown origin have been recorded along the coast of the Tyrrhenian Sea. In this study, we used mitochondrial DNA (mtDNA) analysis of samples from dead embryos collected in C. caretta different nests and from stranded individuals in Tuscany and Latium to provide a preliminary description of the ongoing colonization of the Tyrrhenian coast.
Whole DNA was extracted from samples collected between 2012 and 2023. We sequenced the mtDNA control region of 64 individuals. Of these, a subset of 12 turtles had the whole mitochondrial genome sequenced and assembled. Previously published mitogenomes from our research group were included in the analysis. Haplotypes and haplogroups were assigned based on networks reconstruction and published literature.
Mitogenomic haplotypic diversity was higher than control region haplotypic diversity and a single widespread mtDNA control region haplotype was split in five mitogenomic variants. All the haplotypes recorded in nesting sites belonged to the haplogroup already known in literature as the only one represented in Mediterranean rookeries, while half of the haplotypes recorded in stranded animals belonged to the Atlantic haplogroup.
Our results indicate that attempts to colonize Tuscany and Latium seashores are most probably made by turtles from the Mediterranean, while Atlantic juveniles reach the Mediterranean to forage and for development but not for reproduction. Whole mitogenome sequence analysis also revealed a higher number of maternal lineages in the Tyrrhenian Sea with respect to single genetic markers, advocating the potential of mitogenomic analysis in population ecology studies.

Human tumor cell populations are comparable to communities of individuals within an ecological system, allowing for the application of ecological theories in cancer research. The exploration of group phenotypic composition in cancer - hallmarks of cancers - has highlighted the impact of individual cell traits on the fitness of both the cell and the population, to understand new perspectives on tumor progression and metastasis. Here, we want to illustrate how certain ecological theories can be applied to study some characteristics of tumor cell populations, in particular metabolism and the tumor microenvironment (TME).