scholarly journals A possible 150 million years old cirripede crustacean nauplius and the phenomenon of giant larvae

2017 ◽  
Vol 86 (3) ◽  
pp. 213-227 ◽  
Author(s):  
Christina Nagler ◽  
Jens T. Høeg ◽  
Carolin Haug ◽  
Joachim T. Haug
Keyword(s):  
Upper Jurassic ◽  
Anterior Region ◽  
Single Specimen ◽  
Physiological Mechanisms ◽  
Larval Phase ◽  
Imaging Methods ◽  
Embryonic Period ◽  
The Past ◽  
Giant Larva ◽  
Larval Evolution

The larval phase of metazoans can be interpreted as a discrete post-embryonic period. Larvae have been usually considered to be small, yet some metazoans possess unusually large larvae, or giant larvae. Here, we report a possible case of such a giant larva from the Upper Jurassic Solnhofen Lithographic limestones (150 million years old, southern Germany), most likely representing an immature cirripede crustacean (barnacles and their relatives). The single specimen was documented with up-to-date imaging methods (macro-photography, stereo-photography, fluorescence photography, composite imaging) and compared with modern cirripede larvae. The identification is based on two conspicuous spine-like extensions in the anterior region of the specimen strongly resembling the so-called fronto-lateral horns, structures exclusively known from cirripede nauplius larvae. Notably, at 5 mm in length the specimen is unusually large for a cirripede nauplius. We therefore consider it to be a giant larva and discuss possible ecological and physiological mechanisms leading to the appearance of giant larvae in other lineages. Further findings of fossil larvae and especially nauplii might give new insights into larval evolution and plankton composition in the past.

scholarly journals Split-footed lacewings declined over time: indications from the morphological diversity of their antlion-like larvae

PalZ ◽  
2021 ◽  
Author(s):  
Gideon T. Haug ◽  
Carolin Haug ◽  
Serita van der Wal ◽  
Patrick Müller ◽  
Joachim T. Haug
Keyword(s):  
Morphological Diversity ◽  
Single Specimen ◽  
Burmese Amber ◽  
The Past ◽  
The World ◽  
Poor Group ◽  
Outline Analysis ◽  
Loss Of Diversity ◽  
Over Time ◽  
Antlion Larvae

AbstractNymphidae, the group of split-footed lacewings, is a rather species-poor group. Split-footed lacewings nowadays are restricted to Australasia, while fossil forms are also known from other areas of the world, indicating that the group was more species-rich and therefore likely diverse in the past. Split-footed lacewings have rather distinct larvae, roughly resembling antlion larvae, but differing from the latter especially with regard to the mandibles. Antlion larvae usually have three prominent teeth on each mandible, while at least extant larvae of split-footed lacewings only have a single prominent tooth per mandible. Fossils interpreted as larvae of split-footed lacewings are well known from amber from Myanmar (ca. 100 myr; Burmese amber) and by a single specimen from Baltic amber (about 40 myr). We here report additional fossil specimens from Myanmar amber, expanding the known record of fossil forms from six depicted specimens to 15. For the extant fauna, we could compile 25 larvae. We compare the diversity of shape of extant and fossil larvae through time using an outline analysis (based on elliptic Fourier transformation) of the head. The results of this analysis indicate that the morphological diversity, or disparity, of split-footed lacewing larvae was higher in the past than it is today. With this type of analysis, we can show a loss of diversity over time, without the necessity to identify the fossil larvae down to a narrow taxonomical range. A similar pattern has already been recognised in silky lacewings, Psychopsidae. This might indicate a general loss of diversity of lacewing larvae.

scholarly journals First record ofPhormia regina(Meigen, 1826) (Diptera: Calliphoridae) from mummies at the Sant’Antonio Abate Cathedral of Castelsardo, Sardinia, Italy

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4176 ◽  
Author(s):  
Giorgia Giordani ◽  
Fabiola Tuccia ◽  
Ignazio Floris ◽  
Stefano Vanin
Keyword(s):  
Warm Season ◽  
First Record ◽  
Phormia Regina ◽  
Calliphora Vicina ◽  
Single Specimen ◽  
The Past ◽  
Human Decomposition ◽  
The Family ◽  
The Moment ◽  
Biodiversity Changes

The studies of insects from archaeological contexts can provide an important supplement of information to reconstruct past events, climate and environments. Furthermore, the list of the species present in an area in the past allows the reconstruction of the entomofauna on that area at that time, that can be different from the nowadays condition, providing information about biodiversity changes. In this work, the results of a funerary archaeoentomological study on samples collected from mummified corpses discovered during the restoration of the crypt of the Sant’Antonio Abate Cathedral of Castelsardo (Sardinia, Italy) are reported. The majority of the sampled specimens were Diptera puparia, whereas only few Lepidoptera cocoons and some Coleoptera fragments were isolated. Among Diptera, Calliphoridae puparia were identified asPhormia regina(Meigen, 1826) andCalliphora vicina, (Robineau-Desvoidy, 1830) both species typical of the first colonization waves of exposed bodies. Three puparia fragments were also identified as belonging to aSarcophagaMeigen, 1826, species (Sarcophagidae). Several Muscidae puparia of the speciesHydrotaea capensis(Weidmermann, 1818), a late colonizer of bodies, and typical of buried bodies were also collected. The few moth (Lepidoptera) cocoons were identified as belonging to the family Tineidae. This family comprises species feeding on dry tissues and hair typical of the later phases of the human decomposition. Among Coleoptera a single specimen in the family Histeridae,Saprinus semistriatus(Scriba, 1790) and a single elytra, potentially of a species in the family Tenebrionidae, were also collected. Overall, the samples collected indicated an initial colonization of the bodies in an exposed context, mainly in a warm season. This research allows the finding of elements indicating the presence, at least in the past, ofP. reginain Sardinia. This species at the moment seems extinct from Sardinia while it is quite common in the continent.

I.—Studies on the Physiology of Reproduction in the Ewe. Part I. The Symptoms, Periodicity, and Duration of Œstrus. Part II. Changes in the Vagina and Cervix. Part III. Gross Changes in the Ovaries

1934 ◽  
Vol 58 (1) ◽  
pp. 1-47 ◽  
Author(s):  
R. Grant
Keyword(s):  
Experimental Study ◽  
Reproductive Cycle ◽  
Small Laboratory ◽  
Physiological Mechanisms ◽  
The Past ◽  
Comprehensive Account ◽  
Reproductive Processes

This and the two following papers constitute part of the report upon a detailed investigation of the normal reproductive cycle in the ewe. Although the reproductive processes of mammals have been studied intensively during the past decade, it is to the small “laboratory” mammals that most workers have devoted their attention: little is known regarding reproduction in Ungulates except in relation to the cow, which has been studied by Hammond (1927) and others.Certain aspects of reproduction in the ewe were studied by Marshall (1903) and Assheton (1906). During the last three years many minor papers on this subject have appeared but no comprehensive account is yet available, while, as will be shown in the following pages, many of the conclusions reached by previous workers were based upon examination of insufficient material.It is hoped that this investigation will form the basis for fuller experimental study of reproductive phenomena in the ewe, particularly as they concern breeding practice, and that it will, stimulating interest in the sex physiology of the Ungulates, assist in laying the foundations for a more thorough understanding of the physiological mechanisms underlying reproduction in this group.

Seasonal infertility in pigs: what have we achieved and where are we up to?

2017 ◽  
Vol 57 (12) ◽  
pp. 2325 ◽  
Author(s):  
R. H. King
Keyword(s):  
Practical Experience ◽  
Commercial Production ◽  
Intervention Strategies ◽  
Delayed Puberty ◽  
Physiological Mechanisms ◽  
Prolonged Weaning ◽  
The Past ◽  
The Impact ◽  
Seasonal Infertility ◽  
Farrowing Rate

The most common manifestations of seasonal infertility are delayed puberty, prolonged weaning to oestrus intervals and a reduced farrowing rate brought about by increased returns to oestrus, including a proportionally higher incidence of irregular returns to oestrus. Over the past 40 years, there has been considerable investment in Australian pig research that has generated extensive knowledge about the physiological mechanisms behind seasonal infertility. While some of the physiological mechanisms allowing the expression of seasonal infertility still remain unclear, a number of possible intervention strategies have been developed and investigated to ameliorate the effects of seasonal infertility in commercial production. For commercial pork producers, there is considerable information available that is based on both research and practical experience, which the farmers can use to identify strategies to minimise the impact of seasonal infertility on the farm. The industry still provides some support to research and development efforts to address seasonal infertility, although, in the future, it may be more targeted to identifying interventions to ameliorate the impact of seasonal infertility in affected herds, rather than undertaking intensive studies into the possible mechanisms and reasons behind this very complex syndrome.

Premiere datation par ammonite et brachiopodes du Tithonien au Saleve (Haute-Savoie France), consequences sur l'interpretation stratigraphique de paleogeographique du Jurassique superieur

2000 ◽  
Vol 171 (6) ◽  
pp. 673-680 ◽  
Author(s):  
Raymond Enay ◽  
Annick Boullier
Keyword(s):  
Sea Level ◽  
Carbonate Platform ◽  
Upper Jurassic ◽  
Middle Part ◽  
Type I ◽  
Relative Sea Level ◽  
The Past ◽  
Jurassique Supérieur

Abstract The oldest beds outcropping in the Mt Saleve have in the past been referred to the Kimmeridgian, but an ammonite found in situ together with some brachiopods give them a date somewhere in the middle part of the Lower Tithonian. Recently published interpretation of the local Upper Jurassic stratigraphy and relationship to the Jura platform have therefore to be revised. The Upper Jurassic succession at Saleve is distinguished by a Tithonian continuation of a carbonate platform facies prograding basinward, which compares well with the similar well-known Bec de I'Echaillon, near Grenoble. An erosional disconformity, related by other authors to a fall in relative sea-level and interpreted as a type I sequence boundary associated with a large emergence of the Jura platform, cannot be referred to the Kimmeridgian-Tithonian and must lie somewhere in the Lower Tithonian rocks above the Gravesia beds.

scholarly journals Vascular Functions and Brain Integrity in Midlife: Effects of Obesity and Metabolic Syndrome

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Andreana P. Haley
Keyword(s):  
Cognitive Function ◽  
Functional Ability ◽  
Successful Aging ◽  
Early Interventions ◽  
Physiological Mechanisms ◽  
Clinical Neuroscience ◽  
The Road ◽  
The Past ◽  
Growing Population

Intact cognitive function is the best predictor of quality of life and functional ability in older age. Thus, preventing cognitive decline is central to any effort to guarantee successful aging for our growing population of elderly. The purpose of the work discussed in this outlook paper is to bridge knowledge from basic and clinical neuroscience with the aim of improving how we understand, predict, and treat age- and disease-related cognitive impairment. Over the past six years, our research team has focused on intermediate neuroimaging phenotypes of brain vulnerability in midlife and isolating the underlying physiological mechanisms. The ultimate goal of this work was to pave the road for the development of early interventions to enhance cognitive function and preserve brain integrity throughout the lifespan.

scholarly journals Contemporary Imaging Modalities for Temporomandibular Joint

2021 ◽  
Vol 38 (SI-2) ◽  
pp. 86-91
Author(s):  
Ceren AKTUNA BELGİN ◽  
Gözde SERİNDERE ◽  
Kaan ORHAN
Keyword(s):  
Temporomandibular Joint ◽  
Bone Structure ◽  
Treatment Plan ◽  
New Technology ◽  
Tissue Imaging ◽  
Imaging Method ◽  
Traumatic Injuries ◽  
Imaging Methods ◽  
The Past ◽  
Disc Position

There are different imaging methods used in the evaluation of bone structure, disc, ligaments and muscles that make up Temporomandibular Joint (TMJ). The aim of this review is give information about choice of suitable imaging methods for TMJ diseases from past to present. In the past, conventional radiographs have often been used for TMJ imaging, but nowadays magnetic resonance imaging is the gold standard for soft tissue imaging and disc position determination. Another new technology, ultrasonography can be used for disc displacement, effusion, diagnosis of intraarticular defects. Cone beam computed tomography, it is used for the evaluation of cortical and trabecular structure of bone components of TMJ, developmental anomalies and traumatic injuries affecting TMJ, pathological changes such as osteophyte, erosion, fractures, ankylosis, glenoid fossa-condyle relationship. Nowadays, in parallel with the developing technology, a single imaging method is not used for TMJ imaging and evaluation is performed with several imaging methods. Imaging methods should be selected by evaluating the factors such as radiation dose, contribution to diagnosis and treatment plan, easy applicability.

The first wasps from the Upper Jurassic of Australia (Hymenoptera: Evanioidea, Praeaulacidae) STEFANIE K.

Zootaxa ◽  
2012 ◽  
Vol 3503 (1) ◽  
pp. 47 ◽  
Author(s):  
STEFANIE K. OBERPRIELER ◽  
ALEXANDR P. RASNITSYN ◽  
DENIS J. BROTHERS
Keyword(s):  
Northern Hemisphere ◽  
Upper Jurassic ◽  
Wing Venation ◽  
Single Specimen ◽  
Incertae Sedis

The Hymenoptera fossils discovered in the Upper Jurassic Talbragar Fish Bed in Australia are described and illustrated. Gulgonga beattiei gen. et sp. nov., described from a single specimen, is assigned to the apocritan subfamily Praeaulacinae based primarily on wing venation, mesosomal structure, metasomal articulation, ovipositor shape and antennal form. It is the second member of Praeaulacidae known from Australia; all other praeaulacids have been found in the northern hemisphere. A second Talbragar wasp fossil is assigned to Apocrita incertae sedis because it is too poorly preserved for proper identification.

Brain imaging, ethology, and the nonhuman mind

1995 ◽  
Vol 18 (2) ◽  
pp. 339-340 ◽  
Author(s):  
Gordon M. Burghardt
Keyword(s):  
Brain Imaging ◽  
Cognitive Processes ◽  
Noninvasive Imaging ◽  
Psychological Processes ◽  
Nervous Systems ◽  
Motivational Systems ◽  
Imaging Methods ◽  
The Past ◽  
Future Potential ◽  
Illustrated Book

AbstractPosner & Raichle's (1994) exciting, wonderfully illustrated book describes the past successes and future potential of the relatively noninvasive imaging of the nervous systems of living people. The focus has been on cognitive processes but there is no reason why emotional and motivational systems cannot also be tapped. Although the authors do not formally address such contentious issues as consciousness and the private experience of other species, imaging methods may hold promise for helping us to understand these phenomena, as well as to integrate psychological processes into ethological and phylogenetic research in general.

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