Factors intrinsic and extrinsic to organisms dictate the course of morphological evolution but are seldom considered together in comparative analyses. Among vertebrates, squamates (lizards snakes) exhibit remarkable developmental variations that parallel their incredible ecological spectrum. However, this exceptional diversity also makes systematic quantification analysis challenging. We present a squamate-wide, high-density morphometric skull across 181 modern extinct species identify...

Phylogenetic Principal Components Analysis (pPCA) is a recently proposed method for ordinating multivariatedatainawaythattakesintoaccountthephylogeneticnon-independenceamongspecies means. We review this in terms of geometric morphometric shape analysis and compare its properties to ordinary principal components (PCA). find that pPCA produces space preserves the Procrustes distances between objects, allows models be constructed, scores can used as variables most purposes. Unlike PCA scores,...

Synopsis Advances in imaging technologies, such as computed tomography (CT) and surface scanning, have facilitated the rapid generation of large datasets high-resolution three-dimensional (3D) specimen reconstructions recent years. The wealth phenotypic information available from these has potential to inform our understanding morphological variation evolution. However, ever-increasing ease compiling 3D created an urgent need for sophisticated methods capturing high-density shape data that...

The ecological origin of snakes remains amongst the most controversial topics in evolution, with three competing hypotheses: fossorial; marine; or terrestrial. Here we use a geometric morphometric approach integrating ecological, phylogenetic, paleontological, and developmental data for building models skull shape size evolution rate changes squamates. Our large-scale reveal that whereas recent common ancestor crown had small undeniably adapted fossoriality, all plus their sister group...

Abstract Convergence in morphology can result from evolutionary adaptations species living environments with similar selective pressures. Here, we investigate whether the shape of forelimb long bones has converged imposing functional constraints, using musteloid carnivores as a model. The limbs quadrupeds are subjected to many factors that may influence their shape. They need support body mass without collapsing or breaking, yet at same time resist stresses and strains induced by locomotion....

The field of comparative morphology has entered a new phase with the rapid generation high-resolution three-dimensional (3D) data. With freely available 3D data thousands species, methods for quantifying that harness this rich phenotypic information are quickly emerging. Among these techniques, high-density geometric morphometric approaches provide powerful and versatile framework to robustly characterize shape integration, covariances among morphological traits. These particularly useful...

The Cenozoic diversification of placental mammals is the archetypal adaptive radiation. Yet, discrepancies between molecular divergence estimates and fossil record fuel ongoing debate around timing, tempo, drivers this Analysis a three-dimensional skull dataset for living extinct demonstrates that evolutionary rates peak early attenuate quickly. This long-term decline in tempo punctuated by bursts innovation decreased amplitude over past 66 million years. Social, precocial, aquatic,...

Abstract The ability to grasp and manipulate is often considered a hallmark of hominins associated with the evolution their bipedal locomotion tool use. Yet, many other mammals use forelimbs objects. Previous investigations have suggested that grasping may be derived from digging behaviour, arboreal or hunting behaviour. Here, we test origin investigate whether an lifestyle could confer greater in musteloid carnivorans. Moreover, morphological adaptations related differences between species...

A major goal of evolutionary studies is to better understand how complex morphologies are related the different functions and behaviours in which they involved. For example, during locomotion hunting behaviour, head eyes have stay at an appropriate level order reliably judge distance as well provide postural information. The morphology orientation orbits cranial base will impact on eye orientation. Consequently, variation orbital expected be correlated with aspects animal's lifestyle. In...

The locomotor environment and behavior of quadrupedal mammals exert functional constraints on their limbs. Therefore long bone shapes are thought to reflect at least partially the species' ecology. Semi-aquatic species move through two media with distinct density viscosity apparatus should therefore a trade-off between divergent it faces. Adaptation semi-aquatic lifestyle occurred independently in otters (Lutrinae) minks (Mustelinae). Analyzing mustelids terrestrial relatives, we investigate...

Extreme climate events such as droughts, cold snaps, and hurricanes can be powerful agents of natural selection, producing acute selective pressures very different from the everyday acting on organisms. However, it remains unknown whether these infrequent but severe disruptions are quickly erased by quotidian forces, or they have potential to durably shape biodiversity patterns across regions clades. Here, we show that enduring evolutionary impacts morphology anoles, a diverse Neotropical...

Habitat is one of the most important factors shaping organismal morphology, but it may vary across life history stages. Ontogenetic shifts in ecology introduce antagonistic selection that constrains adult phenotype, particularly with ecologically distinct developmental phases such as free-living, feeding larval stage many frogs (Lissamphibia: Anura). We test relative influences and ecological on diversification skull morphology a detailed analysis 15 individual cranial regions 173 anuran...

The forelimb forms a functional unit that allows variety of behaviours and needs to be mobile, yet at the same time stable. Both mobility stability are controlled, amongst others, level elbow joint. This joint is composed humero-ulnar articulation, mainly involved during parasagittal movements; radio-ulnar allowing rotation. In contrast, humero-radial articulation both movements flexion-extension Here, we study morphological integration between each bone entire arm, as well joint, in...

An organism's morphology is driven by selection on function while being constrained phylogenetic and developmental factors as well functional trade-offs. If strong solutions limited, then convergence expected. In this paper we quantify head shape in a group of ecologically diverse snakes (homalopsid snakes) differing habitat use diet using three-dimensional geometric morphometric approaches. Using data explore whether eating different prey show morphologies. Moreover, test other such use,...

Differences between the sexes may arise because of differences in reproductive strategy, with females investing more traits related to output and males resource holding capacity territory defence. Sexual dimorphism is widespread lizards many species also differ head shape. Males typically have bigger heads than resulting intersexual bite force. Whereas most studies documenting dimensions use linear dimensions, geometric morphometrics has been advocated as appropriate characterize such...

In the majority of mammals, limbs are positioned under body and play an important role in gravitational support, allowing transfer load providing stability to animal. For this reason, animal's mass likely has a significant effect on shape its limb bones. present study, we investigate influence variation three long bones forelimb group closely-related species mammals: musteloid carnivorans. We use geometric morphometric techniques quantify shape; then estimate phylogenetic signal each bone;...

Evolutionary trajectories are often biased by developmental and historical factors. However, environmental factors can also impose constraints on the evolutionary of organisms leading to convergence morphology in similar ecological contexts. The physical properties water strong aquatic feeding animals generating pressure waves that alert prey potentially push them away from mouth. These hydrodynamic have resulted independent evolution suction most groups secondarily tetrapods. Despite fact...

The challenging complexity of biological structures has led to the development several methods for quantitative analyses form. Bones are shaped by interaction historical (phylogenetic), structural, and functional constrains. Consequently, bone shape been investigated intensively in an evolutionary context. Geometric morphometric approaches allow description object all its complexity. However, when objects present only few anatomical landmarks, sliding semi-landmarks may provide good...

Evolutionary integration (covariation) of traits has long fascinated biologists because its potential to elucidate factors that have shaped morphological evolution. Studies tetrapod crania identified patterns evolutionary reflect functional or developmental interactions among traits, but no studies date sampled widely across the species-rich lissamphibian order Anura (frogs). Frogs exhibit a vast range cranial morphologies, life history strategies, and ecologies. Here, using high-density...

Differences in jaw function experienced through ontogeny can have striking consequences for evolutionary outcomes, as has been suggested the major clades of mammals. By contrast to placentals, marsupial newborns an accelerated development head and forelimbs, allowing them crawl mother's teats suckle within just a few weeks conception. The different functional requirements that experience early postnatal hypothesized constrained their morphological diversification relative placentals. Here,...

Vertebrate limb morphology often reflects the environment due to variation in locomotor requirements. However, proximal and distal segments may evolve differently from one another, reflecting an anatomical gradient of functional specialization that has been suggested be impacted by timing development. Here, we explore whether temporal sequence bone condensation predicts capacity evolution generate morphological diversity forelimb across more than 600 species mammals. Distal elements not only...