Morphological evolution

On the Article-like Use of the Px2Sg in Dolgan, Nganasan and Some Other Languages in an Areal Siberian Context

by Marek Stachowski

Px2Sg = Possessive suffix of the second person singular.

This is a (polemic) continuation of the article "An example of Nganasan-Dolgan linguistic contact."

SKULL SHAPE AND SIZE DIVERGENCE IN DOLPHINS OF THE GENUS SOTALIA: A TRIDIMENSIONAL MORPHOMETRIC ANALYSIS

by Leandro Monteiro

Comparative analysis of cranial suture complexity in the genus Caiman (Crocodylia, alligatoridae)

by Leandro Monteiro

Morphological divergence rate tests for natural selection: uncertainty of parameter estimation and robustness of results

by Leandro Monteiro

Darwin´s pigeons and the evolution of columbiforms: recapitulation of ancient genes

by Juan Martínez-Gómez

Acta Zoológica Mexicana (n.s.) 25(3): 719-741.  2009.

To commemorate the sesquicentennial of Charles Darwin´s “On the Origin of Species by Means of Natural Selection”, we... more To commemorate the sesquicentennial of Charles Darwin´s “On the Origin of Species by Means of Natural Selection”, we address an essential topic in this publication. Domestic pigeons were extremely important in shaping Darwin’s theory of evolution: pigeons featured prominently not only in his “Origin of Species”, but also in his treatise on “Variation under Domestication”, in his “Descent of Man” and finally in his “Expression of Emotions”. Darwin saw the process of domestication as solid evidence demonstrating the power of selection. He argued convincingly that all domestic pigeon breeds (some 150 in his day) descended from one ancestral species, the Rock Dove (Columba livia), and that from this single species, humans selected directionally for colors, sizes, shapes, peculiarities of bill shape and length, plumage characteristics and voice qualities. While these domestic races achieved remarkable morphological differentiation under selection in the course of human generations, extant genera of pigeons (Columbiformes) have attained similar traits during the course of natural selection in the wild. We present a comparison of such characters between modern domestic breeds of the Rock Dove, the original Darwin´s Pigeons plus new breeds, and wild pigeon species to encourage further studies on their evolution in the light of molecular techniques not available at Darwin´s time.

Morphological differentiation and hybridization between Quercus alnifolia Poech and Quercus coccifera L.(Fagaceae) in Cyprus

by Charalambos Neophytou

Middle Miocene freshwater mollusks from Lake Sinj (Dinaride Lake System, SE Croatia; Langhian)

by Thomas A. Neubauer

Thomas A. Neubauer, Oleg Mandic, Mathias Harzhauser
Archiv für Molluskenkunde

This study provides the first assemblage-based taxonomic revision of the mollusk fauna of the Middle Miocene Dinaride... more This study provides the first assemblage-based taxonomic revision of the mollusk fauna of the Middle Miocene Dinaride Lake System (DLS). The assemblage, consisting of more than 13.000 specimens, was sampled from a 100-m-thick Lower Langhian interval of the Lučane section in the Sinj Basin (Croatia). 18 gastropod species and 3 bivalve species are detected from the succession. All are endemic to the Dinaride Lake System. Within that system, the described fauna of Lake Sinj displays strong similarities with the coeval and geographically close fauna of Lake Drniš. Reduced faunistic relations to other lakes of the DLS are discussed to result from slightly different stratigraphic ages and deviating paleoecologic settings. Many melanopsid and prososthenid gastropod taxa in the literature are considered to be mere morphotypes of few polymorphic species resulting in nomenclatorial rectifications.
Melanopsis lucanensis NEUBAUER n. sp. and Belgrandia klietmanni NEUBAUER n. sp. are introduced as new species.

Evolution of Reproductive Morphology In Leaf Endophytes

by Jeffrey Townsend

The endophytic lifestyle has played an important role in the evolution of the morphology of reproductive structures... more The endophytic lifestyle has played an important role in the evolution of the morphology of reproductive structures (body) in one of the most problematic groups in fungal classification, the Leotiomycetes (Ascomycota). Mapping fungal morphologies to two groups in the Leiotiomycetes, the Rhytismatales and Hemiphacidiaceae reveals significant divergence in body size, shape and complexity. Mapping ecological roles to these taxa reveals that the groups include endophytic fungi living on leaves and saprobic fungi living on duff or dead wood. Finally, mapping of the morphologies to ecological roles reveals that leaf endophytes produce small, highly reduced fruiting bodies covered with fungal tissue or dead host tissue, while saprobic species produce large and intricate fruiting bodies. Intriguingly, resemblance between asexual conidiomata and sexual ascomata in some leotiomycetes implicates some common developmental pathways for sexual and asexual development in these fungi.

Baeza, J.A. and C. Asorey. 2012. Testing the role of male-male competition in the evolution of sexual dimorphism: a comparison between two species of porcelain crabs. Biological Journal of the Linnean Society 105:548–558.

by Antonio Baeza

Geographical and morphological variation within and between colour phases in Coris julis (L. 1758), a protogynous marine fish

by Carmelo Fruciano

The possible differences between sexes in patterns of morphological variation in geographical space have been explored... more The possible differences between sexes in patterns of morphological variation in geographical space have been explored only in gonochorist freshwater species. We explored patterns of body shape variation in geographical space in a marine sequential hermaphrodite species, Coris julis (L. 1758), analyzing variation both within and between colour phases, through the use of geometric morphometrics and spatially-explicit statistical analyses. We also tested for the association of body shape with two environmental variables: temperature and chlorophyll a concentration, as obtained from time-series of satellite-derived data. Both colour phases showed a significant morphological variation in geographical space and patterns of variation divergent between phases. Although the morphological variation was qualitatively similar, individuals in the initial colour phase showed a more marked variation than individuals in the terminal phase. Body shape showed a weak but significant correlation with environmental variables, which was more pronounced in primary specimens.

Body shape variation and colour change during growth in a protogynous fish

by Carmelo Fruciano

Protogynous sequential hermaphroditism is very common in marine fish. Despite a large number of studies on various... more Protogynous sequential hermaphroditism is very common in marine fish. Despite a large number of studies on various aspects of sequential hermaphroditism in fish, the relationship between body shape and colour during growth in dichromatic species has not been assessed. Using geometric morphometrics, the present study explores the relationship between growth, body shape and colouration in Coris julis (L. 1758), a small protogynous labrid species with distinct colour phases. Results show that body shape change during growth is independent of change in colour phase, a result which can be explained by the biology of the species and by the social control of sex change. Also, during growth the body grows deeper and the head has a steeper profile. It is hypothesized that a deeper body and a steeper profile might have a function in agonistic interactions between terminal phase males and that the marked chromatic difference between colour phases allows the lack of strict interdependence of body shape and colour during growth.

ODONTOGLIFIA EN UNA POBLACIÓN PREHISPÁNICA DE TRADICIÓN CULTURAL SONSO UBICADA EN YUMBO, VALLE DEL CAUCA, COLOMBIA (Spanish)

by Carlos David Rodriguez Florez

Forensic method to determine gender in sub adult subjects using odontometrics in the deciduous dentition

by Carlos David Rodriguez Florez

Dimorfismo sexual de rugas palatinas en subadultos de la ciudad de Córdoba, Argentina

by Carlos David Rodriguez Florez

The A-Mode Sutural Ontogeny In Prolecanitid Ammonoids

by Dieter Korn

Integrating fossils and molecules to study cupuladriid evolution in an emerging Isthmus

by Aaron O'Dea

Fossils and genes represent two principal sources of data for studying evolutionary biology, but they are rarely... more Fossils and genes represent two principal sources of data for studying evolutionary biology, but they are rarely unified. The aim of this paper is to integrate the fossil and molecular records of Tropical American cupuladriid bryozoans to elucidate their evolutionary history. Molecules and fossils broadly concur in determining the timing of species divergences, and point to seaway constriction associated with the emergence of the Isthmus of Panama as a driver of speciation. We discover that although cross-Isthmian isolation of taxa was important, strong isolating mechanisms also existed within the southwestern Caribbean (SWC), caused by increasing physical and environmental heterogeneity as inter-oceanic straits constricted in the Late Pliocene. During this time of rapid environmental change and instability, recently diverged species pairs existed in locally separated habitats for around 2 million years, only to co-exist after final closure of the seaway. This pattern is consistent with a model of allopatric speciation caused by local isolating mechanisms followed by secondary contact. Fossils also reveal the trajectories of reproductive life history and morphology during and after species divergences. In the SWC, all extant species started to shift from clonal to aclonal reproduction immediately in response to changing oceanographic conditions. However, it took another million years for colonies to gain skeletal strength, a trait that reduces cloning by fragmentation, suggesting that the appearance of advantageous traits was delayed by 1–2 million years and only arose after the process of allopatric speciation had run its course. Changes in colony shape, height and size also appear to lag 2 million years, but may reflect exploitation of the diverse sedimentary environments created as reefs proliferated at this time.

Evolution of the Goniatitaceae and Viséan-Namurian Biogeography

by Dieter Korn

Morphological Pathways In the Evolution of Early and Middle Devonian Ammonoids

by Dieter Korn

The Ammonoid Faunal Change Near the Devonian-Carboniferous Boundary

by Dieter Korn

Morphological Disparity of Ammonoids and the Mark of Permian Mass Extinctions

by Dieter Korn