Biology subjects

Carere, C.

Publications and source records attributed to Carere, C..

8 recordsLinked to original sources

bioRxiv2023

Different behavioural profiles between invasive and native nudibranchs: means for invasion success?

Behaviour is predicted to be a primary determinant of the success of the invasion process during the early phases of colonization. Comparing sympatric invaders and native species may provide a good approach to unravel behavioural traits involved in an invasion process. In this study, we carried out an experimental simulation of the introduction and the establishment phase into a new environment and assessed the expression of activity, alertness and habituation in a non-indigenous Mediterranean population of the South African nudibranch Godiva quadricolor comparing its profiles with those of the sympatric native Cratena peregrina and Caloria quatrefagesi. Individuals of these three species were subjected to three behavioural tests: spontaneous activity, carried out in the introduction phase (immediately after sampling) and after a week of acclimatization; alert test, in which a potential threat was simulated by means of a tactile stimulus; habituation test, where the same alert test stimulus was repeated five times at thirty- minute intervals. Native nudibranch had repeatable traits, although with species differences perhaps related to their different ecological niches. The comparison with the invasive species highlighted its low repeatability in activity levels, suggesting higher plasticity, a strong tendency to locomotor activity, and a marked sensitization in the habituation test. Such traits could play an important and active role in the ongoing invasion process.

animal behavior and cognition↗

bioRxiv2022

Atmospheric hydrogen oxidation extends to the domain archaea

Diverse aerobic bacteria use atmospheric hydrogen (H2) and carbon monoxide (CO) as energy sources to support growth and survival. Though recently discovered, trace gas oxidation is now recognised as a globally significant process that serves as the main sink in the biogeochemical H2 cycle and sustains microbial biodiversity in oligotrophic ecosystems. While trace gas oxidation has been reported in nine phyla of bacteria, it was not known whether archaea also use atmospheric H2. Here we show that a thermoacidophilic archaeon, Acidianus brierleyi (Thermoproteota), constitutively consumes H2 and CO to sub-atmospheric levels. Oxidation occurred during both growth and survival across a wide range of temperatures (10 to 70{degrees}C). Genomic analysis demonstrated that A. brierleyi encodes a canonical carbon monoxide dehydrogenase and, unexpectedly, four distinct [NiFe]-hydrogenases from subgroups not known to mediate aerobic H2 uptake. Quantitative proteomic analyses showed that A. brierleyi differentially produced these enzymes in response to electron donor and acceptor availability. A previously unidentified group 1 [NiFe]-hydrogenase, with a unique genetic arrangement, is constitutively expressed and upregulated during stationary phase and aerobic hydrogenotrophic growth. Another archaeon, Metallosphaera sedula, was also found to oxidize atmospheric H2. These results suggest that trace gas oxidation is a common trait of aerobic archaea, which likely plays a role in their survival and niche expansion, including during dispersal through temperate environments. These findings also demonstrate that atmospheric H2 consumption is a cross-domain phenomenon, suggesting an ancient origin of this trait, and identify previously unknown microbial and enzymatic sinks of atmospheric H2 and CO.

microbiology↗

bioRxiv2022

Within-flock differences in exploratory tendency and flock performance in a highly gregarious bird

How individual differences translate into group outcomes is a timely and debated issue. Recent studies, especially in social arthropods and fish, focus on diversity of personality traits. These studies suggest that the phenotypic group assortment by personality type of an animal group, including the presence of "keystone" individuals, leads to group-level personality differences and can strongly impact both group and individual outcomes. However, little attention has been given to the variation of a given trait within a group. Theory predicts that phenotypic homogeneity rather than heterogeneity yields the optimal group performance, especially in an anti-predatory context, but the experimental support includes mainly morphological traits, e.g. body size or colouration. Here, we focus on personality and group level differences in a highly gregarious bird, the European starling (Sturnus vulgaris). We investigated how different degrees of within-flock variation in exploration affect flock outcomes in exploratory behaviour and in escape response after a frightening stimulus. First, we established consistent individual differences in exploration. Then, flocks of 4 birds were formed to obtain gradual differences in mean and in variation of exploration scores among flocks. Flocks underwent an exploration test and a perturbation test. More exploratory individuals entered the test arena earlier, tended to start flying more rapidly and also stopped flying sooner upon frightening. Flocks with a more homogeneous distribution with respect to this personality trait were significantly faster to enter the test room, but no effect on the escape response emerged. The mean exploration tendency of the flock or the maximum exploration tendency of purported key individuals within groups did not play a notable role in explaining such differences in group performance. Our results indicate that it is not the individual that predicts/drives the flock outcome, but rather a group feature, namely phenotypic variation within the group.

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

Improved deterrence of birds using an artificial predator, the RobotFalcon

Collisions between birds and airplanes, bird strikes, can damage aircrafts, resulting in delays and cancellation of flights, costing the international civil aviation industry more than 1.4 billion U.S. dollars annually. Bird deterrence is therefore crucial, but the effectiveness of all available deterrence methods is limited. For example, live avian predators can be a highly effective deterrent, because potential prey will not habituate to them, but live predators cannot be controlled with sufficient precision. Thus, there is an urgent need for new deterrence methods. To this end we developed the RobotFalcon, a device that we modelled after the peregrine falcon, a cosmopolitan predator that preys on a large range of bird species. Mimicking natural hunting behaviour, we tested the effectiveness of the RobotFalcon to deter flocks of corvids, gulls, starlings and lapwings. We compared its effectiveness with that of a drone, and of conventional methods routinely applied at a military airbase. We show that the RobotFalcon scared away bird flocks from fields immediately, and these fields subsequently remained free of bird flocks for hours. The RobotFalcon outperformed the drone and the best conventional method at the airbase (distress calls). Importantly, there was no evidence that bird flocks habituated to the RobotFalcon. We propose the RobotFalcon to be a practical and ethical solution to drive away bird flocks with all advantages of live predators but without their limitations. HighlightsO_LIWe present and test a new method of deterring of deterring birds, the RobotFalcon. C_LIO_LIThe RobotFalcon chased away flocks fast and prevented early returns. C_LIO_LIThe RobotFalcon outperformed both a drone and convential methods. C_LIO_LINo evidence of habituation to the RobotFalcon was found during the study period. C_LI

animal behavior and cognition↗

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↗

bioRxiv2022

Sex differences in migration timing influence the network structure of avian assemblages at a stopover site

Migratory species are changing the timing of departures from wintering areas and arrival to breeding sites (i.e., migration phenology), as response to climate change to exploit maximum food availability at higher latitudes and improve their fitness. Despite the impact of changing migration phenology on migratory connectivity at population and community level, the extent to which such individual and species-specific response affects associations among co-migrating species has been seldom explored. By applying temporal co-occurrence network models on 15 years of standardized bird ringing data at a spring stopover site, we show that African-European migratory landbirds tend to migrate in well-defined groups of species with high temporal overlap. Such co-migration fidelity is significantly increasing over the years and higher in trans-Saharan than North-African migrants. Our findings suggest non-random patterns of associations in co-migrating species, possibly related to the existence of regulatory mechanisms associated with changing climate conditions and different uses of stopover sites by migrants, ultimately influencing the global migration economy of landbirds in the Palearctic-African migration system.

ecology↗