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This paper reports the first detection of polarization in the X-rays for atoll-source 4U 1820-303, obtained with the Imaging X-ray Polarimetry Explorer (IXPE) at 99.999% confidence level (CL). Simultaneous polarimetric measurements were also performed in the radio with the Australia Telescope Compact Array (ATCA). The IXPE observations of 4U 1820-303 were coordinated with Swift-XRT, NICER, and NuSTAR aiming to obtain an accurate X-ray spectral model covering a broad energy interval. The source shows a significant polarization above 4 keV, with a polarization degree of 2.0(0.5)% and a polarization angle of -55(7) deg in the 4-7 keV energy range, and a polarization degree of 10(2)% and a polarization angle of -67(7) deg in the 7-8 keV energy bin. This polarization also shows a clear energy trend with polarization degree increasing with energy and a hint for a position-angle change of about 90 deg at 96% CL around 4 keV. The spectro-polarimetric fit indicates that the accretion disk is polarized orthogonally to the hard spectral component, which is presumably produced in the boundary/spreading layer. We do not detect linear polarization from the radio counterpart, with a 99.97% upper limit of 50% at 7.25 GHz.

The climate during the Plio-Pleistocene was deeply influenced by the so called Milankovitch cycles (Zachos et al.,2001). These are combinations of different astronomical phenomena involving the variation of the Earth’s orbital eccentricity, the axis obliquity and precession. The first phenomenon was estimated to occur every 400-100 Ka, whereas the others occur over a time period of 41 and 23-19 Ka, respectively. These astronomical variations influenced the Earth-Sun distance and the angular incidence of solar rays with a net effect on the global climate change (Zachos et al., 2001). The Early Pliocene was characterized by a decrease of the global temperature, a trend that began during the Late Miocene. The measure of the mean 16O/18O values indicates a trend of warmer climate until 3.2 Mya, the latter that represents the onset of a new temperature cycle. During these cycles the ice sheet expanded and contracted according to the variation of the mean global temperature. Indeed, in the Middle Pliocene, the ice sheets began to cover the Northern Hemisphere, an event indicated as NHG (North Hemisphere Glaciation) (Shackleton et al., 1998; Maslin et al., 1998; Zachos et al., 2001). At ~2.5 Mya the oscillations of the temperature became quite a regular pattern determining the alternation between warmer (Interglacials) and cooler (Glacials) time periods, that were to characterize the Pleistocene. Some 1 May (period coincident with the Jaramillo Event of Earth’s Magnetic Field inversion) the time interval of a complete climatic cycle changed its duration from the 41-23-19 Kya., to a new longer cycle of 100 Kya, probably determined Earth’s orbital eccentricity variation. With the increase of the duration of the cycles the mean global temperatures reached more extreme values and there were stronger climate ranges between warm and cold periods. Moreover, the measures of the oxygen isotopes ratios confirm a net decrement of mean temperature values recorded from the Late Pliocene to the Recent (Zachos et al., 2001). The strong oscillations of the temperatures during the Plio-Pleistocene deeply influenced the faunas of the whole world. These environmental changes determined local or mass extinctions in some cases or migration events in other cases (Lister, 2004). In particular, during the Glacials, the species adapted to warmer climates migrated southward, while, during the Interglacials, the species adapted to low temperatures migrated northward (Vrba, 1995b). There are many demonstrations of the influence of the climate changes on the evolution of mammals faunas, also at the community level (Vrba, 1995a,b; Alroy et al., 2000; Fortelius et al., 2002, 2006; Barnosky et al., 2003; Bobe and Behrensmeyer, 2004; Rodríguez et al., 2004; Raia et al., 2005; Barnosky and Kraatz, 2007; Meloro et al, 2008). Starting from these considerations on the evolution of mammal faunas, the aims of this doctoral thesis were focused on the detection of the paleocommunities of large mammals that lived since the Late Pliocene to the Early Holocene in the Western Eurasia and on their macroecological investigations in the light of climatic change. After collecting a great deal of data (811 Local Faunal Assemblages, LFA, and 220 large mammal species) the paleocommunities (here called EA PCOM) were detected using new statistical methods that avoid any subjective criteria in selecting the LFAs. Moreover, considering two recent articles (Alroy, 2000; Fortelius et al., 2006) a statistical-based time ordination of the collected fossil localities was obtained. As for their well defined temporal and geographical resolution, the EA PCOMs were discussed from the point of view of the distribution of the included LFAs. These analyses showed the presence of both spatial and temporal patterns, useful for inferring dispersal events of mammals in response to the environmental changes. From this point of view, EA PCOMs provide a paleontological framework for evolutionary and ecological investigations. All the collected LFAs were then used to perform statistical analyses to detect macroecological patterns that usually characterize the living mammal assemblages. At first, there were the reconstruction of the body masses and of the duration of both species and genera of the considered taxa. Then, the fossil mammal faunas were investigated to draw the occupancy and the range size trajectories over taxa life span, both at the species level and at the genera level. To this aim the occupancies and the range sizes were computed in different moment of taxon life time. Further, the data provided by occupancy and range size values were used to draw general models that decribe the most frequent coarses in both species and genera time life span. Some other statistics were computed over occupancy, range size and body size and, then, used to infer on their possible influences on the taxon duration. In addition, the data of the species occurrences were used to build the species-time, the species-area and the species-time-area relationship (STAR), that are all patterns typically recognized in living species. Moreover, the latter model (the STAR) was investigated for the first time in fossil species. The interdisciplinary approach of this doctoral thesis also involved the use of modern phylogenetic techniques to seek any relationships in all the measured traits between closely related taxa. To this aim, the phylogenetic trees of all the considered species and genera were reconstructed using data provided by genetic, morphologic and evolutionary studies. A second step was to combine the phylogenetic trees and all the other computed measures to infer about the models of evolution followed by the traits characterizing the large fossil mammals. All the computed results were used to draw possible evolutionary scenarios concerning the Plio-Pleistocene mammal faunas.

Wild rocket is a widely cultivated salad crop. Typical signs and symptoms of powdery mildew were observed on leaves of Diplotaxis tenuifolia, likely favored by climatic conditions occurring in a greenhouse. Based on morphological features and molecular analysis, the disease agent was identified as the fungal pathogen Erysiphe cruciferarum. To the best of our knowledge, this is the first report of E. cruciferarum on D. tenuifolia. Moreover, the present study provides a non-destructive high performing digital approach to efficiently detect the disease. Hyperspectral image analysis allowed to characterize the spectral response of wild rocket affected by powdery mildew and the adopted machine-learning approach (a trained Random Forest model with the four most contributory wavelengths falling in the range 403–446 nm) proved to be able to accurately discriminate between healthy and diseased wild rocket leaves. Shifts in the irradiance absorption by chlorophyll a of diseased leaves in the spectrum blue range seems to be at the base of the hyperspectral imaging detection of wild rocket powdery mildew.

Mammalian megaherbivores are an essential component of modern day ecosystems. They control a large share of primary productivity, modify habitats by clearing dense vegetation, and keep other herbivores populations small. When rare, small herbivores additionally suffer increased extinction risk by predation. Since megaherbivores are almost immune to predation, it was suggested that the detrimental effect of megaherbivores on smaller competitors has the additional consequence to reduce the prey biomass available to predatory species, thereby increasing their extinction risk. This form of indirect competition between guilds of species is known as apparent competition. These mechanisms are all forms of top-down control on ecosystem functioning, whereby species up on the food chain control diversity at lower levels. We tested these competing hypotheses on a large compilation of Neogene to Recent Old World mammals.We found evidence in favor of apparent competition. However, direct competition effects by both megaherbivores and carnivores on small prey are even more pervasive. Our results suggest that megaherbivores have been a dominant component of the mammal diversity over time and space during the last 22. million. years in Eurasia. © 2017 Elsevier B.V.

The dispersal of Homo erectus out of Africa at some 1.9 million years ago is one of the most important, crucial, and yet controversial events in human evolution. Current opinions about this episode expose the contrast between those who see H. erectus as a highly social, cooperative species seeking out new ecological opportunities to exploit, and those preferring a passive, climate driven explanation for such an event. By using geostatistics techniques and probabilistic models, we characterised the ecological context of H. erectus dispersal, from its East African origin to the colonization of Eurasia, taking into account both the presence of other large mammals and the physical characteristics of the landscape as potential factors. Our model indicated that H. erectus followed almost passively the large herbivore fauna during its dispersal. In Africa, the dispersal was statistically associated with the presence of large freshwater bodies (Rift Valley Lakes). In Eurasia, the presence of H. erectus was associated with the occurrence of geological outcrops likely yielding unconsolidated flint. During the early phase of dispersal, our model indicated that H. erectus actively avoided areas densely populated by large carnivores. This pattern weakened as H. erectus dispersed over Europe, possibly because of the decreasing presence of carnivores there plus the later acquisition of Acheulean technology. During this later phase, H. erectus was associated with limestone and shaley marl, and seems to have been selecting for high-elevation sites. While our results do not directly contradict the idea that H. erectus may have been an active hunter, they clearly point to the fact that predator avoidance may have conditioned its long-distance diffusion as it moved outside Africa. The modelled dispersal route suggests that H. erectus remained preferentially associated with low/middle latitude (i.e., comparatively warm) sites throughout its colonization history. © 2016 Elsevier Ltd.

Body mass has important physiological and ecological implications. The high degree of variability in herbivore mammals' body mass is linked to differences in their gut anatomy, which, in turn, has important effects on their feeding habits. We aimed to untangle the effects of Cope's and Bergmann's rule on the evolution of body size in even-toed hoofed mammals (Artiodactyla, Mammalia). By using variation partitioning techniques and direct sister species comparisons, we estimated the potential effects of latitude, time and phylogeny on body size variation in Cenozoic Artiodactyls. We tested whether species tend to be larger when living at higher latitudes as compared to their phylogenetically closest relative, whether closely-related species living in sympatry tend to diverge more in body size, and whether recent species tend to be larger than their older relatives. Our results showed that both latitudinal and temporal trends in Artiodactyla body size are evident throughout the Cenozoic, and became particularly intense during the coldest part of it. Artiodactyls tend to be larger than their close relatives when living at higher latitudes, in keeping with Bergmann's rule. Yet, this relationship is weakened by the strong tendency for sister species to diverge in body size when living nearby. We also found a clear tendency for late Artiodactyl species to be larger, and live for shorter, than their ancestors.Thus, there is strong evidence that the evolution of body size in even-toed hoofed mammals was influenced by climatic changes, and by an overall tendency to grow larger, mostly in coincidence with the vegetation shift from forested to grassland biomes which characterized the second half (Neogene) of the Cenozoic. Although Cope's and Bergmann's rule in mammals are often portrayed as having climate change as a common explanation, our data suggest they are mechanistically separate phenomena. © 2015 Elsevier B.V.

The city of Napoli, Italy is an interesting case study for landslide susceptibility assessment, due to its complex interactions between landslides and anthropic fabric. In fact, despite the long history of slope instabilities, the urban evolution, often illegal, disregarded the high landslide propensity of the hillsides and occupied unsafe lands, exposing the population to a high level of risk. This study focuses on three municipality districts of the city, Soccavo, Pianura and Arenella, over which impends the Camaldoli Hill, the most prominent Phlegraean peak (458 m a.s.l.), where more than 300 landslides of the 1300 events recorded from 1850 to date in the Napoli municipality landslide geodatabase, occurred. In this paper the landslide susceptibility assessment has been carried out applying the Maximum Entropy method (MaxEnt). The results have been critically validated using Boyce index and, eventually, compared to the official map provided in the Hydro-geomorphological Setting Plan (HSP) redacted by the competent governmental agency (River Basin Authority) by means of a semi-statistical approach already in use by the research group.

Our aim is to identify ecomorphological adaptations in the skull shape of the South American howler monkeys (species of the genus Alouatta , Lacepede, 1799 , Primates, Atelidae). Since Alouatta is relatively homogenous in feeding ecology, we expect skull shape variation to be relatively conservative across species. We used geometric morphometrics to quantify craniodental morphology in six species of Alouatta . Multivariate regression, two-block Partial Least Squares, and variation partitioning were used to test for the impact of taxonomy, sexual dimorphism, allometry, geography and climate on skull shape. We found morphological overlap among species and sexes, although some discrimination occurs between species living in seasonal environments as opposed to rain forest species. There was a negative latitudinal gradient in skull size across species, with size explaining 34% of total shape variance. Latitude and climate, though important, were secondary in explaining shape variance. Amazonian Alouatta are larger, have thinner molars, wide incisors, and proportionally larger neurocranium. Overall, the shape of southern species seem well adapted to cope with proportionally tougher food items, whereas Amazonian species seem better equipped to deal with a diet richer in fruits, as confirmed by independent field observations. The small size of Alouatta in the South is possibly linked to the effect of competition with the larger folivorous atelid Brachyteles .

Species co-occur with different sets of other species across their geographical distribution,which can be either closely or distantly related. Such co-occurrence patterns and their phylogenetic structure within individual species ranges represent what we call the species phylogenetic fields (PFs). These PFs allow investigation of the role of historical processes—speciation, extinction and dispersal—in shaping species co-occurrence patterns, in both extinct and extant species. Here, we investigate PFs of large mammalian species during the last 3 Myr, and how these correlate with trends in diversification rates. Using the fossil record, we evaluate species’ distributional and co-occurrence patterns along with their phylogenetic structure. We apply a novel Bayesian framework on fossil occurrences to estimate diversification rates through time. Our findings highlight the effect of evolutionary processes and past climatic changes on species’ distributions and co-occurrences. From the Late Pliocene to the Recent, mammal species seem to have responded in an individualistic manner to climate changes and diversification dynamics, co-occurring with different sets of species from different lineages across their geographical ranges. These findings stress the difficulty of forecasting potential effects of future climate changes on biodiversity. © 2016 The Author(s) Published by the Royal Society. All rights reserved.

Fil: Raia, Pasquale. Università degli Studi di Napoli Federico II; Italia Fil: Passaro, Federico. Università degli Studi di Napoli Federico II; Italia Fil: Carotenuto, Francesco. Università degli Studi di Napoli Federico II; Italia Fil: Maiorino, Leonardo. Università degli Studi Roma Tre; Italia Fil: Piras, Paolo. Università degli Studi Roma Tre; Italia Fil: Teresi, Luciano. Università degli Studi Roma Tre; Italia Fil: Meiri, Shai. Tel Aviv University; Israel Fil: Itescu, Yuval. Tel Aviv University; Israel Fil: Novosolov, Maria. Tel Aviv University; Israel Fil: Baiano, Mattia A. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Baiano, Mattia A. Instituto Catalán de Paleontología Miquel Crusafont; España Fil: Baiano, Mattia A. Universidad Nacional de Río Negro; Argentina Fil: Martínez, Ricard. Universitat Autònoma de Barcelona; España Fil: Fortelius, Mikael. University Of Helsinski; Finlandia Luxuriant, bushy antlers, bizarre crests, and huge, twisting horns and tusks are conventionally understood as products of sexual selection. This view stems from both direct observation and from the empirical finding that the size of these structures grows faster than body size (i.e., ornament size shows positive allometry).We contend that the familiar evolutionary increase in the complexity of ornaments over time in many animal clades is decoupled from ornament size evolution. Increased body size comes with extended growth. Since growth scales to the quarter power of body size, we predicted that ornament complexity should scale according to the quarter power law as well, irrespective of the role of sexual selection in the evolution and function of the ornament. To test this hypothesis, we selected three clades (ammonites, deer, and ceratopsian dinosaurs) whose species bore ornaments that differ in terms of the importance of sexual selection to their evolution.We found that the exponent of the regression of ornament complexity to body size is the same for the three groups and is statistically indistinguishable from0.25.We suggest that the evolution of ornament complexity is a by-product of Cope’s rule. We argue that although sexual selection may control size in most ornaments, it does not influence their shape.

The acquisition of hypsodont molars is often regarded as a key innovation in the history of ruminant ungulates. Hypsodont ruminants diversified rapidly during the later Neogene, circa 15–2 Myr ago, and came to dominate the ruminant fossil record in terms of species diversity. Here we show that hypsodont clades had higher speciation and diversification rates than other clades. Hypsodont species had, on average, shorter stratigraphic durations, smaller range size and lower occupancy than non-hypsodont species. Within hypsodont clades, some species were very common and acquired large geographical ranges, whereas others were quite rare and geographically limited. We argue that hypsodont clades diversified in an adaptive radiation-like fashion, with species often splitting cladogenetically while still in the expansive phase of their occupancy history.

A classic question in evolutionary biology concerns the tempo and mode of lineage evolution. Considered variously in relation to resource utilization, intrinsic constraints or hierarchic level, the question of how evolutionary change occurs in general has continued to draw the attention of the field for over a century and a half. Here we use the largest species-level phylogeny of Coenozoic fossil mammals (1031 species) ever assembled and their body size estimates, to show that body size and taxonomic diversification rates declined from the origin of placentals towards the present, and very probably correlate to each other. These findings suggest that morphological and taxic diversifications of mammals occurred hierarchically, with major shifts in body size coinciding with the birth of large clades, followed by taxonomic diversification within these newly formed clades. As the clades expanded, rates of taxonomic diversification proceeded independently of phenotypic evolution. Such a dynamic is consistent with the idea, central to the Modern Synthesis, that mammals radiated adaptively, with the filling of adaptive zones following the radiation.