Search results for "Geometric morphometrics"
showing 9 items of 29 documents
The Human Biodiversity in the Middle of the Mediterranean. Study of native and settlers populations on the Sicilian context
2020
[IT] Negli ultimi 200.000 anni, la specie umana si è diffusa in tutta la Terra, adattando la sua morfologia e fisiologia a un'ampia gamma di habitat. Lo scheletro umano ha quindi registrato i principali effetti ambientali e di conseguenza i reperti scheletrici assumono grande importanza nell'indagine dei processi evolutivi. Oggi le moderne tecniche di indagini quantitative delle principali caratteristiche morfologiche consentono di metterle in relazione con la variabilità genetica. La posizione geografica della Sicilia, l'isolamento e la sua lunga e dinamica storia di colonizzazione (diversi e numerosi contributi culturali e biologici) hanno creato un contesto peculiare che consente uno stu…
Morphological variability in and distributional data on phaleria bimaculata populations from islands of the central mediterranean area
2011
This study aimed to collect new taxonomic and distribution data on Phaleria bimaculata (L.) (Coleoptera Tenebrionidae) from Sicily (southern Italy), the circum-Sicilian islands and the Maltese archipelago. Particular attention was paid to the diagnostic morphological features observed in the populations sampled, focusing on the subspecies Phaleria bimaculata marcuzzii Aliquò. P. bimaculata individuals were collected from 20 different locations, of which 2 were located in the Sicilian mainland, 9 in circum-Sicilian islands and 9 in the Maltese Islands. In addition, four Phaleria acuminata Kuster populations were also recorded along southern Sicilian shores. The two Phaleria species were neve…
Differences in inner ear asymmetry levels between slow-moving and fast-moving primates
2021
International audience; The vestibular system of the inner ear, highly involved in maintaining balance during activities and positional behaviour of animals, has been deeply studied in order to link its morphology with the specific type of locomotion. Previous studies (e.g. Perier et al. 2016, Gonzales et al. 2018) have shown that, in primates, the amount of morphological variation is higher in slow-moving species than in fast-moving ones. These results indicate a lower selective pressure and a reduced functional demand for postural adjustments in the former group, and a higher selective pressure for balance and postural capabilities in the latter. In this study, we assessed if the differen…
Morphometric diversity of the mussel Brachidontes pharaonis in different coastal environments
2010
In the debate on how and why biodiversity evolves spatially and temporally and in an attempt to assess the further effects of anthropogenic activities, the ability of marine invertebrate to express a large spectrum of phenotypical plasticity can have a central role. The ability of a single genotype to produce more than one alternative form of morphology and/or physiological state should be larger in species living in highly changing waters like shallow habitats. Invertebrates, there, usually experience ample changes of temperature and food availability on annual, seasonal, diurnal and hourly bases which are the two main drivers leading the life histories of these organisms. In such circumst…
3D Geometric morphometrics to investigate Cercopithecini evolution
2014
3D Geometric Morphometrics has been used on a preliminary dataset of 163 crania and 148 mandibles of primates. We sampled 27 species from Cercopithecidae and Hominidae, collected in 7 different museums. Our sampling campaign was carried on with the use of a 3D-digitizer Microscribe G2X and the data were processed through the software Morphologika. The preliminary PCA analyses on crania highlight the presence of two different groups, which distinguish some Chlorocebus and Unknown Cercopithecus samples from all the others. Regarding on mandibular shape analyses, we found a light cluster of Cercopithecus samples. The “Sex” variable does not affect the reliability of the analysis, probably beca…
Développement postnatal et évolution du complexe craniofacial chezles rongeurs
2022
Understanding developmental mechanisms in evolution is crucial to apprehend the diversification of organismal forms. In mammals, changes occur during all development phases (prenatal and postnatal). Postnatal growth plays an essential role in the acquisition of the adult shape. During this period, the craniofacial complex undergoes many changes in functional constraint forcing the different tissue to accommodate while adjusting, along the growth and at the adult stage, to a certain level of functional performance. These different developmental interactions respond to several influencing factors such as molecular, genetic and cellular processes but also the environment. The latter will play …
Human-induced hybridization and population bottleneck : population genetics, morphometrics and parasitology applied to the invaded and invasive tilap…
2011
Biological invasions are recognized as a significant evolutionary factor over short time scales. In particular, their effect is well recorded on the genetic structure of populations, the patterns of phenotypic evolution and the richness of parasite fauna associated to invasive populations. This study aims at quantifying the consequences of a biological invasion according to these three levels (genetical, phenotypical and parasitological) taking as example the Mozambique tilapia Oreochromis mossambicus. This African cichlid is characterized by an unusual conservation status since it is both (i) ranked among the world’s worst invasive species due to its global dispersion during the 20th centu…
Productions en série vers 1500 avant notre ère. Des règles de fabrication au Bronze moyen entre la Manche et les Alpes à la lumière d’une étude morph…
2013
Some European Bronze Age objects were produced by what has been described as serial metalworking. One particularexample is the Middle Bronze Age palstave, massively produced and used in Western Europe during the mid-second millennium BC.These artefacts were often voluntarily buried together in hoards, meaning they were removed from the production network, thus avoidingany recycling. They are found intact, either as rough castings or ready for use. These homogeneous objects are grouped in sets of severalitems, or in tens, or even in hundreds. Such discoveries have immediately led to numerous questions as to the possible interpretation ofthis behaviour. It is clear that prehistoric craftsmen …
(no title)
2017
Biological invasions are recognized as a significant evolutionary factor over short time scales. In particular, their effect is well recorded on the genetic structure of populations, the patterns of phenotypic evolution and the richness of parasite fauna associated to invasive populations. This study aims at quantifying the consequences of a biological invasion according to these three levels (genetical, phenotypical and parasitological) taking as example the Mozambique tilapia Oreochromis mossambicus. This African cichlid is characterized by an unusual conservation status since it is both (i) ranked among the world's worst invasive species due to its global dispersion during the 20th centu…