Adaptations to semi-terrestrial life in embryos of East African mangrove crabs: a comparative approach

2013 ◽  
Vol 160 (9) ◽  
pp. 2483-2492 ◽  
Author(s):  
Riccardo Simoni ◽  
Folco Giomi ◽  
Daniele Spigoli ◽  
Hans-Otto Pörtner ◽  
Stefano Cannicci
Keyword(s):  
Comparative Approach ◽  
East African ◽  
Terrestrial Life ◽  
Mangrove Crabs

Feeding and burrowing ecology of two East African mangrove crabs

1991 ◽  
Vol 111 (2) ◽  
pp. 247-254 ◽  
Author(s):  
F. Micheli ◽  
F. Gherardi ◽  
M. Vannini
Keyword(s):  
East African ◽  
Mangrove Crabs

scholarly journals Forests as promoters of terrestrial life-history strategies in East African amphibians

2013 ◽  
Vol 9 (3) ◽  
pp. 20121146 ◽  
Author(s):  
Hendrik Müller ◽  
H. Christoph Liedtke ◽  
Michele Menegon ◽  
Jan Beck ◽  
Liliana Ballesteros-Mejia ◽  
...  
Keyword(s):  
Montane Forest ◽  
Breeding Strategy ◽  
Life History Strategies ◽  
Strongly Correlated ◽  
Breeding Strategies ◽  
East African ◽  
Amphibian Species ◽  
Terrestrial Life ◽  
Potential Factor ◽  
Forest Habitats

Many amphibian lineages show terrestrialization of their reproductive strategy and breeding is partially or completely independent of water. A number of causal factors have been proposed for the evolution of terrestrialized breeding. While predation has received repeated attention as a potential factor, the influence of other factors such as habitat has never been tested using appropriate data or methods. Using a dataset that comprises 180 amphibian species from various East African habitats, we tested whether species occurring in different habitats show different patterns of terrestrialization in their breeding strategy. We recovered a significant association between terrestrialized breeding strategies and forest habitats. In general, forest seems to act as a facilitator, providing a permissive environment for the evolution of terrestrialized breeding strategies. However, while terrestrial oviposition is strongly correlated with lowland and montane forest habitat, complete terrestrial development is significantly correlated with montane forest only, indicating different selective pressures acting at different steps towards complete terrestrial development.

scholarly journals Comparative analyses of olfactory systems in terrestrial crabs (Brachyura): evidence for aerial olfaction?

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1433 ◽  
Author(s):  
Jakob Krieger ◽  
Philipp Braun ◽  
Nicole T. Rivera ◽  
Christoph D. Schubart ◽  
Carsten H.G. Müller ◽  
...  
Keyword(s):  
Olfactory System ◽  
Three Dimensional ◽  
Comparative Approach ◽  
Evolutionary Transition ◽  
Chemical Senses ◽  
Terrestrial Life ◽  
Dimensional Reconstruction ◽  
Limited Function ◽  
Olfactory Systems ◽  
Anatomical Adaptations

Adaptations to a terrestrial lifestyle occurred convergently multiple times during the evolution of the arthropods. This holds also true for the “true crabs” (Brachyura), a taxon that includes several lineages that invaded land independently. During an evolutionary transition from sea to land, animals have to develop a variety of physiological and anatomical adaptations to a terrestrial life style related to respiration, reproduction, development, circulation, ion and water balance. In addition, sensory systems that function in air instead of in water are essential for an animal’s life on land. Besides vision and mechanosensory systems, on land, the chemical senses have to be modified substantially in comparison to their function in water. Among arthropods, insects are the most successful ones to evolve aerial olfaction. Various aspects of terrestrial adaptation have also been analyzed in those crustacean lineages that evolved terrestrial representatives including the taxa Anomala, Brachyura, Amphipoda, and Isopoda. We are interested in how the chemical senses of terrestrial crustaceans are modified to function in air. Therefore, in this study, we analyzed the brains and more specifically the structure of the olfactory system of representatives of brachyuran crabs that display different degrees of terrestriality, from exclusively marine to mainly terrestrial. The methods we used included immunohistochemistry, detection of autofluorescence- and confocal microscopy, as well as three-dimensional reconstruction and morphometry. Our comparative approach shows that both the peripheral and central olfactory pathways are reduced in terrestrial members in comparison to their marine relatives, suggesting a limited function of their olfactory system on land. We conclude that for arthropod lineages that invaded land, evolving aerial olfaction is no trivial task.

Homochirality as the Signature of Extra-Terrestrial Life

1997 ◽  
Vol 161 ◽  
pp. 505-510
Author(s):  
Alexandra J. MacDermott ◽  
Laurence D. Barron ◽  
Andrè Brack ◽  
Thomas Buhse ◽  
John R. Cronin ◽  
...  
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Optical Rotation ◽  
Physical Origin ◽  
Natural Choice ◽  
Rosetta Mission ◽  
Terrestrial Life ◽  
Subsurface Layers ◽  
Solar System Bodies ◽  
Origin Of Homochirality

AbstractThe most characteristic hallmark of life is its homochirality: all biomolecules are usually of one hand, e.g. on Earth life uses only L-amino acids for protein synthesis and not their D mirror images. We therefore suggest that a search for extra-terrestrial life can be approached as a Search for Extra- Terrestrial Homochirality (SETH). The natural choice for a SETH instrument is optical rotation, and we describe a novel miniaturized space polarimeter, called the SETH Cigar, which could be used to detect optical rotation as the homochiral signature of life on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. We believe that homochirality may be found in the subsurface layers on Mars as a relic of extinct life, and on other solar system bodies as a sign of advanced pre-biotic chemistry. We discuss the chiral GC-MS planned for the Roland lander of the Rosetta mission to a comet and conclude with theories of the physical origin of homochirality.

Scanning electron microscopy of the integument of schistosoma rodhaini

1986 ◽  
Vol 44 ◽  
pp. 132-133
Author(s):  
P. Evers ◽  
C. Schutte ◽  
C. D. Dettman
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Oral Sucker ◽  
Adult Male ◽  
Dorsal Surface ◽  
Ventral Surface ◽  
Sensory Receptors ◽  
East African ◽  
Dorsal Midline ◽  
Scanning Electron

S.rodhaini (Brumpt 1931) is a parasite of East African rodents which may possibly hybridize with the human schistosome S. mansoni. The adult male at maturity measures approximately 3mm long and possesses both oral and ventral suckers and a marked gynaecophoric canal. The oral sucker is surrounded by a ring of sensory receptors with a large number of inwardly-pointing spines set into deep sockets occupying the bulk of the ventral surface of the sucker. Numbers of scattered sensory receptors are found on both dorsal and ventral surfaces of the head (Fig. 1) together with two conspicuous rows of receptors situated symmetrically on each side of the midline. One row extends along the dorsal surface of the head midway between the dorsal midline and the lateral margin.

Lectin-Induced RBC Agglutination: Chemical vs. Cryofixation

1980 ◽  
Vol 38 ◽  
pp. 664-665
Author(s):  
Dean A. Handley ◽  
Lanping A. Sung ◽  
Shu Chien
Keyword(s):  
Lectin Binding ◽  
Freeze Substitution ◽  
Electrostatic Charge ◽  
Geometric Parameters ◽  
Comparative Approach ◽  
Chemical Fixation ◽  
Cell Surfaces ◽  
Minimal Cell ◽  
Membrane Stiffness ◽  
Cell Contour

RBC agglutination by lectins represents an interactive balance between the attractive (bridging) force due to lectin binding on cell surfaces and disaggregating forces, such as membrane stiffness and electrostatic charge repulsion (1). During agglutination, critical geometric parameters of cell contour and intercellular distance reflect the magnitude of these interactive forces and the size of the bridging macromolecule (2). Valid ultrastructural measurements of these geometric parameters from agglutinated RBC's require preservation with minimal cell distortion. As chemical fixation may adversely influence RBC geometric properties (3), we used chemical fixation and cryofixation (rapid freezing followed by freeze-substitution) as a comparative approach to examine these parameters from RBC agglutinated with Ulex I lectin.

International Telesupervision: The Clinical Fellowship Experience

2017 ◽  
Vol 2 (11) ◽  
pp. 73-78
Author(s):  
David W. Rule ◽  
Lisa N. Kelchner
Keyword(s):  
Graduate Students ◽  
Clinical Supervision ◽  
Rural Areas ◽  
The United States ◽  
Speech Language Pathology ◽  
Access To Services ◽  
East African ◽  
The World ◽  
Language Pathology ◽  
National Certification

Telepractice technology allows greater access to speech-language pathology services around the world. These technologies extend beyond evaluation and treatment and are shown to be used effectively in clinical supervision including graduate students and clinical fellows. In fact, a clinical fellow from the United States completed the entire supervised clinical fellowship (CF) year internationally at a rural East African hospital, meeting all requirements for state and national certification by employing telesupervision technology. Thus, telesupervision has the potential to be successfully implemented to address a range of needs including supervisory shortages, health disparities worldwide, and access to services in rural areas where speech-language pathology services are not readily available. The telesupervision experience, potential advantages, implications, and possible limitations are discussed. A brief guide for clinical fellows pursuing telesupervision is also provided.

Ivan Ozhienko about the role of religion in Ukrainian national life

2001 ◽  
pp. 54-61
Author(s):  
K. Nedzelsky
Keyword(s):  
Ethnic Identity ◽  
Spiritual Life ◽  
Human Soul ◽  
National Unity ◽  
Terrestrial Life ◽  
Dedicated Service ◽  
National Life ◽  
Role Of Religion ◽  
Spiritual Unity

Ivan Ogienko (1882-1972), also known as Metropolitan Hilarion, devoted much attention to the role and place of religion in the national life of Ukrainians and their ethnic identity in their scholarly and theological works. Without exaggeration it can be argued that the problem of national unity of the Ukrainian people is one of the key principles of all historiosophical considerations of the famous scholar and theologian. If the purpose of the spiritual life of a Ukrainian, according to his views, is to serve God, then the purpose of state or terrestrial life is the dedicated service to his people. The purpose of heaven and the purpose of the earthly paths, intersecting in the life of a certain group of people through the lives of its individual representatives, give rise to a unique alliance of spiritual unity, the name of which is "people" or "nation." Religion (faith) in the process of transforming the anarchist crowd into a spiritually integrated and orderly national integrity serves as the transformer of the imperfect nature of the human soul into perfect.

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