geometric morphometrics

Evaluating the island effect on phenotypic evolution in the Italian wall lizard, Podarcis siculus (Reptilia: Lacertidae)

Islands are compelling natural laboratories for studying evolutionary processes. Nevertheless, the existence of general rules underlying morphological evolution on islands remains an unresolved issue. In this study, we investigated the insular phenotypic variability of the Italian wall lizard (Podarcis siculus) on a large geographical scale, in order to assess the putative existence of an island effect on three morphological head traits: shape, size and degree of sexual dimorphism.

A study in scarlet: incipient speciation, phenotypic differentiation and conservation implications of the Podarcis lizards of the western Pontine islands, Italy

During the first decades of the last Century an enigmatic extinction was documented to have occurred on the small Mediterranean island of Santo Stefano and Sherlock Holmes was jokingly evoked to solve the mystery. Although islands are fascinating systems where to study microevolutionary processes, they may, on the other hand, host unstable communities that make their populations particularly vulnerable to anthropogenic effects and even to extinctions.

Asymmetric hybridization in Cordulegaster (Odonata: Cordulegastridae): Secondary postglacial contact and the possible role of mechanical constraints

Two Cordulegaster dragonflies present in Italy, the Palaearctic and northern distributed Cordulegaster boltonii and the endemic to the south of the peninsula Cordulegaster trinacriae, meet in central Italy and give rise to individuals of intermediate morphology. By means of mitochondrial and nuclear markers and of Geometric Morphometrics applied to sexual appendages, we defined i) the geographical boundaries between the two species in Italy and ii) we determined the presence, the extent, and the genetic characteristics of the hybridization.

Mandible size and shape in extant Ursidae (Carnivora, Mammalia): a tool for taxonomy and ecogeography

The family Ursidae is currently one of the taxonomic group with the lowest number of species among Carnivora. Extant bear species exhibit broad ecological adaptations both at inter and intra specific level and taxonomic issues within this family remain unresolved (i.e. the number of

Influence of evolutionary allometry on rates of morphological evolution and disparity in strictly subterranean moles (talpinae, talpidae, lipotyphla, mammalia)

The adaptation to a particular function could directly influence the morphological evolution of an anatomical structure as well as its rates. The humeral morphology ofmoles (subfamily Talpinae) is highly modified in response to

Measuring the shape. Performance evaluation of a photogrammetry improvement applied to the Neanderthal skull Saccopastore 1

Several digital technologies are nowadays developed and applied to the study of the human fossil record. Here, we present a low-cost hardware implementation of the digital acquisition via photogrammetry, applied to a specimen of paleoanthropological interest: the Neanderthal skull Saccopastore 1. Such implementation has the purpose to semi-automatize the procedures of digital acquisition, by

Virtual Anthropology and its Application in Cultural Heritage Studies

The remains that typically compose the human fossil record often bear cracks, damage, and deformations. The recent rapid development of ‘virtual anthropology’ has provided innovative tools to manage, study, and preserve cultural and natural heritage. Such tools include computerized tomography (CT), laser scanning, photogrammetry, 3D imaging, and rapid prototyping. These approaches can contribute to any archaeological context from the discovery of artefacts to research, preservation, and dissemination.

Seeing the wood through the trees. Combining shape information from different landmark configurations

The geometric morphometric (GM) analysis of complex anatomical structures is an ever more powerful tool to study biological variability, adaptation and evolution. Here, we propose a new method (combinland), developed in R, meant to combine the morphological information contained in different landmark coordinate sets into a single dataset, under a GM context. combinland builds a common ordination space taking into account the entire shape information encoded in the starting configurations. We applied combinland to a Primate case study including 133 skulls belonging to 14 species.

A new tool for digital alignment in virtual anthropology

The study of the fossil record is fundamental to understand the evolution of traits. Because fossil remains are often fragmented and/or deformed by taphonomic processes, a preliminary realignment of their constituent parts is often necessary to properly interpret their shapes. In virtual anthropology, these procedures are carried out using digital models of the remains. We present a new semi-automatic alignment R software, Digital Tool for Alignment (DTA), which uses the shape information contained in a reference sample to find the best alignment solution for the disarticulated regions.

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