Number of Neoblasts in the Intact Body of Euplanaria torva and Dendrocoelum lacteum

Development ◽  
1961 ◽  
Vol 9 (1) ◽  
pp. 167-172
Author(s):  
Agnes Brøndsted ◽  
H. V. Brøndsted
Keyword(s):  
The Body ◽  
Regeneration Ability ◽  
Characteristic Variation ◽  
Species Specific ◽  
Regeneration Blastema

The regeneration, blastema in planarians is constituted by the totipotent neoblasts which migrate to the wound (Dubois, 1949). The rate of regeneration, measured by appearance of eyes in the blastema, shows a characteristic variation throughout the planarian body, thus constituting a static, time-graded regeneration field (Brøndsted, 1946). We do not know the mechanism underlying this species-specific feature. Neither do we know why some species, e.g. Dendrocoelum lacteum, are able to regenerate a head only from the part of the body lying anteriorly to the pharynx, whereas other species, e.g. Euplanaria torva, can regenerate a head from almost every part of the body. A possible explanation might be the number of available neoblasts. This idea was formulated by Curtis & Schulze (1934). They claim that in Procotyla fluviatilis, a species closely related to D. lacteum, the inability to regenerate a head from parts behind the pharynx is due to scarcity of neoblasts, as compared with species with greater regeneration ability.

What's hot and what's not: defining torpor in free-ranging birds and mammals

2001 ◽  
Vol 79 (10) ◽  
pp. 1885-1890 ◽  
Author(s):  
Robert MR Barclay ◽  
Cori L Lausen ◽  
Lydia Hollis
Keyword(s):  
Body Temperature ◽  
The Body ◽  
Temperature Sensitive ◽  
The Past ◽  
Data Loggers ◽  
Temperature Thresholds ◽  
Radio Transmitters ◽  
Species Specific ◽  
Free Ranging ◽  
Lowered Body

With the development of small implantable data loggers and externally attached temperature-sensitive radio transmitters, increasing attention is being paid to determining the thermoregulatory strategies of free-ranging birds and mammals. One of the constraints of such studies is that without a direct measure of metabolic rate, it is difficult to determine the significance of lowered body temperatures. We surveyed the literature and found that many different definitions have been used to discriminate torpor from normothermy. Many studies use arbitrary temperature thresholds without regard for the normothermic body temperature of the individuals or species involved. This variation makes comparison among studies difficult and means that ecologically and energetically significant small reductions in body temperature may be overlooked. We suggest that normothermic body temperature for each individual animal should be determined and that torpor be defined as occurring when the body temperature drops below that level. When individuals' active temperatures are not available, a species-specific value should be used. Of greater value, however, are the depth and duration of torpor bouts. We suggest several advantages of this definition over those used in the past.

Species-specific patterns of the use of burrows of Upogebia Leach, 1814 (Decapoda: Gebiidea: Upogebiidae) by the symbiotic alpheid shrimps Stenalpheops anacanthus Miya, 1997 and Athanas japonicus Kubo, 1936 (Decapoda: Caridea: Alpheidae) as revealed by laboratory quantification

2020 ◽  
Author(s):  
Yumi Henmi ◽  
Gyo Itani
Keyword(s):  
Evolutionary Biology ◽  
Evolutionary History ◽  
The Body ◽  
Symbiotic Relationship ◽  
Use Patterns ◽  
Species Specific ◽  
Burrow Use ◽  
First Time ◽  
The Relationship ◽  
Observation Period

Abstract Many alpheid shrimps live symbiotically on the body surface or inside the bodies of other invertebrates, while others use burrows made by other animals. The burrow symbiosis of alpheid shrimps is poorly studied in the context of ecology, probably because the cryptic infaunal nature of the relationship is hard to observe. The limited knowledge of the pattern of burrow use by alpheid shrimps leaves a gap in our understanding of their evolutionary history. We described and compared the behavior of Stenalpheops anacanthus  Miya, 1997 and Athanas japonicus  Kubo, 1936, two alpheid species living symbiotically in the burrows of the same host, Upogebia yokoyai  Makarov, 1938. We found that both alpheid species used U. yokoyai burrows in aquaria, but their burrow use patterns were quite different. The average time taken for S. anacanthus to enter the burrow for the first time was much shorter (1 min) than that of A. japonicus (13 min). Subsequently, S. anacanthus made longer use of the burrow (80% of the observation period) than A. japonicus (49%). The tail-first exit frequency, which may indicate a sudden expulsion from the burrow by the host, was more frequent in A. japonicus (25%) than in S. anacanthus (7%). Such differences could be attributed to the nature of the symbiotic relationship, obligate in S. anacanthus but facultative in A. japonicus. Because of the diversity of symbiotic lifestyles, there is considerable potential to study the ecology and evolutionary biology of burrow-symbiotic alpheids further.

scholarly journals Three-dimensional visualization and a deep-learning model reveal complex fungal parasite networks in behaviorally manipulated ants

2017 ◽  
Vol 114 (47) ◽  
pp. 12590-12595 ◽  
Author(s):  
Maridel A. Fredericksen ◽  
Yizhe Zhang ◽  
Missy L. Hazen ◽  
Raquel G. Loreto ◽  
Colleen A. Mangold ◽  
...  
Keyword(s):  
Deep Learning ◽  
Behavioral Control ◽  
Three Dimensional ◽  
The Body ◽  
Fungal Parasite ◽  
Carpenter Ant ◽  
Block Face ◽  
Species Specific ◽  
Deep Learning Model ◽  
Ophiocordyceps Unilateralis

Some microbes possess the ability to adaptively manipulate host behavior. To better understand how such microbial parasites control animal behavior, we examine the cell-level interactions between the species-specific fungal parasite Ophiocordyceps unilateralis sensu lato and its carpenter ant host (Camponotus castaneus) at a crucial moment in the parasite’s lifecycle: when the manipulated host fixes itself permanently to a substrate by its mandibles. The fungus is known to secrete tissue-specific metabolites and cause changes in host gene expression as well as atrophy in the mandible muscles of its ant host, but it is unknown how the fungus coordinates these effects to manipulate its host’s behavior. In this study, we combine techniques in serial block-face scanning-electron microscopy and deep-learning–based image segmentation algorithms to visualize the distribution, abundance, and interactions of this fungus inside the body of its manipulated host. Fungal cells were found throughout the host body but not in the brain, implying that behavioral control of the animal body by this microbe occurs peripherally. Additionally, fungal cells invaded host muscle fibers and joined together to form networks that encircled the muscles. These networks may represent a collective foraging behavior of this parasite, which may in turn facilitate host manipulation.

scholarly journals ГЕОМЕТРИЧЕСКИЕ ПАРАМЕТРЫ ЯИЦ В СИСТЕМАТИКЕ ПТИЦ

2014 ◽  
Vol 4 (03) ◽  
pp. 98
Author(s):  
I. S. Mityay ◽  
A. V. Matsyura
Keyword(s):  
Complex Traits ◽  
Comparative Anatomy ◽  
Morphological Characteristics ◽  
The Body ◽  
Geometrical Parameters ◽  
Significant Similarity ◽  
Additional Information ◽  
Morphological Criteria ◽  
Bird Eggs ◽  
Species Specific

<p>Our ideas are based on the following assumptions. Egg as a standalone system is formed within another system, which is the body of the female. Both systems are implemented on the basis of a common genetic code. In this regard, for example, the dendrogram constructed by morphological criteria eggs should be approximately equal to those constructed by other molecular or morphological criteria adult birds. It should be noted that the dendrogram show only the degree of genetic similarity of taxa, therefore, the identity of materials depends on the number of analyzed criteria and their quality, ie, they should be the backbone. The greater the number of system-features will be included in the analysis and in one other case, the like are dendrogram. In other cases, we will have a fragmentary similarity, which is also very important when dealing with controversial issues. The main message of our research was to figure out the eligibility of usage the morphological characteristics of eggs as additional information in taxonomy and phylogeny of birds.</p> <p>Our studies show that the shape parameters of bird eggs show a stable attachment to certain types of birds and complex traits are species-specific. Dendrogram and diagrams built by the quantitative value of these signs, exhibit significant similarity with the dendrogram constructed by morphological, comparative anatomy, paleontology and molecular criteria for adult birds. This suggests the possibility of using morphological parameters eggs as additional information in dealing with taxonomy and phylogeny of birds.</p> <p><em>Keywords: oology, geometrical parameters of eggs, bird systematics</em></p>

Captive husbandry and veterinary care of seabirds during the MV Rena oil spill response

2019 ◽  
Vol 46 (7) ◽  
pp. 610 ◽  
Author(s):  
B. D. Gartrell ◽  
P. F. Battley ◽  
C. Clumpner ◽  
W. Dwyer ◽  
S. Hunter ◽  
...  
Keyword(s):  
Body Condition ◽  
The Body ◽  
Fuel Oil ◽  
Heavy Fuel Oil ◽  
Seabird Species ◽  
Rehabilitation Protocols ◽  
Common Causes ◽  
Oil Spill Response ◽  
Species Specific

Abstract ContextSeabirds were the most common taxa captured alive as part of the oiled wildlife response to the grounding of the container vessel MV Rena in the Bay of Plenty, New Zealand. AimsTo describe the management of seabirds during the spill response, to outline the common problems encountered and to make recommendations for future responses. MethodsSeabirds were collected from 7 October 2011 to 14 January 2012. They were stabilised and underwent pretreatment, washing and rinsing procedures to remove oil, followed by swimming physiotherapy to restore waterproofing and long-term housing in outdoor aviaries. The birds were released in batches close to the original sites of capture once the wild habitat was cleaned. Key results428 live seabirds were admitted. There were two temporal peaks in admissions associated with the ship grounding and when the ship broke up. The majority of live birds were little penguins (Eudyptula minor; 394/428, 92%). Most seabirds admitted (393/428, 91.8%) were contaminated with heavy fuel oil, with the remainder (35/428, 8.2%) found unoiled but starving and/or exhausted or with injuries. Little penguins had lower mortality during rehabilitation (28/394, 7.1%) than other seabird species combined (27/34, 79.4%). Seabirds in poorer body condition on arrival had higher mortality, and unoiled birds were also more likely to die than oiled birds. In oiled little penguins, the degree of oiling on the plumage ranged from 1 to 100%, but mortality was not significantly associated with the degree of oiling (P=0.887). Pododermatitis affected 66% of little penguins. The most common causes of death (n=45) included weakness, anaemia and hypothermia in oiled seabirds (16/45, 35.6%), and starvation and weakness in unoiled seabirds (14/45, 31.1%). ConclusionsTotal survival to release was 87.1%, primarily influenced by the species involved and the body condition of the birds on arrival. Unoiled seabirds had higher mortality rates than oiled seabirds. ImplicationsOiled wildlife can be rehabilitated with good success, even when heavily oiled, or to a lesser extent, when found in poor body condition. More work is needed to refine species-specific rehabilitation protocols for seabirds, especially for those being admitted in emaciated body condition.

The electric organ discharge of pulse gymnotiforms: the transformation of a simple impulse into a complex spatio-temporal electromotor pattern

1999 ◽  
Vol 202 (10) ◽  
pp. 1229-1241 ◽  
Author(s):  
A.A. Caputi
Keyword(s):  
Spinal Cord ◽  
Electric Organ Discharge ◽  
Electric Organ ◽  
The Body ◽  
Size Principle ◽  
Spatio Temporal ◽  
Electromotor System ◽  
Discharge Patterns ◽  
Species Specific ◽  
Pacemaker Nucleus

An understanding of how the nervous system processes an impulse-like input to yield a stereotyped, species-specific electromotor output is relevant for electric fish physiology, but also for understanding the general mechanisms of coordination of effector patterns. In pulse gymnotids, the electromotor system is repetitively activated by impulse-like signals generated by a pacemaker nucleus in the medulla. This nucleus activates a set of relay cells whose axons descend along the spinal cord and project to electromotor neurones which, in turn, project to electrocytes. Relay neurones, electromotor neurones and electrocytes may be considered as layers of a network arranged with a lattice hierarchy. This network is able to coordinate a spatio-temporal pattern of postsynaptic and action currents generated by the electrocyte membranes. Electrocytes may be innervated at their rostral face, at their caudal face or at both faces, depending on the site of the organ and the species. Thus, the species-specific electric organ discharge patterns depend on the electric organ innervation pattern and on the coordinated activation of the electrocyte faces. The activity of equally oriented faces is synchronised by a synergistic combination of delay lines. The activation of oppositely oriented faces is coordinated in a precise sequence resulting from the orderly recruitment of subsets of electromotor neurones according to the ‘size principle’ and to their position along the spinal cord. The body of the animal filters the electric organ output electrically, and the whole fish is transformed into a distributed electric source.

Modern diagnosis of IgE-mediated allergy – molecular diagnosis of allergies

2016 ◽  
Vol 52 (1) ◽  
pp. 45-50
Author(s):  
Sławomir Białek ◽  
Katarzyna Białek-Gosk
Keyword(s):  
Molecular Diagnosis ◽  
Molecular Diagnostics ◽  
Clinical Symptoms ◽  
Comprehensive Evaluation ◽  
Diagnostic Technique ◽  
Specific Ige ◽  
The Body ◽  
Individual Risk ◽  
Cross Reactions ◽  
Species Specific

Diagnostic difficulties resulting from the imperfections of natural allergen extracts inspired to use genetic engineering techniques to produce recombinant allergens or obtaining highly purified components (component) allergen. This led to the development of modern diagnostic technique in allergy or molecular diagnostics. The basis for understanding the molecular diagnosis of allergies is to know the properties of allergens. Each allergen is composed of various proteins known. component capable of sensitizing allergen, and each component includes a plurality of epitopes that can be divided into one species-specific epitopes, and the identical amino acid structure of the epitopes derived from different species. Specific epitopes are responsible for primary sensitization, while the epitopes with similar structures are responsible for cross-reactions. Finding sensitization several epitopes is a strong indication of the occurrence of much more dangerous allergic reactions than only one epitope. In addition, molecular diagnosis of allergies allows for personalized diagnosis of allergic patients. It enables the assessment of individual risk of allergic symptoms and allows you to distinguish the original from allergy symptoms caused by cross-reactions. It should be noted, however, that the diagnosis of allergy should be based on a comprehensive evaluation of the results and their confrontation with data from the interview. The mere detection of allergen-specific IgE antibodies, even the method of molecular diagnostics, without the presence of clinical symptoms does not confirm an allergy or illness. Only goes to confirm that the body of such a person is allergic and that the symptoms of this condition may at some point reveal but not necessarily.

Influence of Temperature on Rate of Regeneration in the Time-graded Regeneration Field in Planarians

Development ◽  
1961 ◽  
Vol 9 (1) ◽  
pp. 159-166
Author(s):  
Agnes Brøndsted ◽  
H. V. Brøndsted
Keyword(s):  
The Body ◽  
Influence Of Temperature ◽  
High Point ◽  
Know How ◽  
Influence Of Temperature On ◽  
Temperature Levels ◽  
Species Specific ◽  
Head Regeneration

There exists in planarians a time-graded regeneration field for head regeneration (Brøndsted, 1946, 1956; A. & H. V. Brøndsted, 1952). The characteristics of this field, expressed by rate of regeneration, are species-specific. The existence of this field ensures harmonious regeneration from cuts everywhere in the body, as a cut will always expose a ‘high point’ where regeneration of a head starts with greatest speed, thus taking the lead in organization and at the same time inhibiting head-forming tendencies elsewhere in the blastema (Brøndsted, 1956). The factors underlying these characteristics of the field are unknown; the problems involved are being attacked from several angles in our laboratory. For the sake of this work it is of some interest to know how the different rates of regeneration at various levels in the time-graded fields might be influenced by various temperature levels. Material and Methods The experiments were carried out on two species differing greatly in the characteristics of their time-graded regeneration fields.

scholarly journals Growth and size control during development

Open Biology ◽  
2017 ◽  
Vol 7 (11) ◽  
pp. 170190 ◽  
Author(s):  
Jannik Vollmer ◽  
Fernando Casares ◽  
Dagmar Iber
Keyword(s):  
Drosophila Melanogaster ◽  
Size Control ◽  
General Rule ◽  
Developmental Time ◽  
The Body ◽  
Organ Size ◽  
Animal Kingdom ◽  
Definitive Answer ◽  
Vinegar Fly ◽  
Species Specific

The size and shape of organs are characteristic for each species. Even when organisms develop to different sizes due to varying environmental conditions, such as nutrition, organ size follows species-specific rules of proportionality to the rest of the body, a phenomenon referred to as allometry. Therefore, for a given environment, organs stop growth at a predictable size set by the species's genotype. How do organs stop growth? How can related species give rise to organs of strikingly different size? No definitive answer has been given to date. One of the major models for the studies of growth termination is the vinegar fly Drosophila melanogaster. Therefore, this review will focus mostly on work carried out in Drosophila to try to tease apart potential mechanisms and identify routes for further investigation . One general rule, found across the animal kingdom, is that the rate of growth declines with developmental time. Therefore, answers to the problem of growth termination should explain this seemingly universal fact. In addition, growth termination is intimately related to the problems of robustness (i.e. precision) and plasticity in organ size, symmetric and asymmetric organ development, and of how the ‘target’ size depends on extrinsic, environmental factors.

scholarly journals Visual signal evolution along complementary color axes in four bird lineages

Biology Open ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. bio052316
Author(s):  
Anand Krishnan ◽  
Avehi Singh ◽  
Krishnapriya Tamma
Keyword(s):  
Color Space ◽  
The Body ◽  
Color Variation ◽  
Visual Signals ◽  
Visual Signal ◽  
Chromatic Contrast ◽  
Present Evidence ◽  
Complementary Color ◽  
Line Passing ◽  
Species Specific

ABSTRACTAvian color patterns function in varied behavioral contexts, most being produced by only a handful of mechanisms including feather nanostructures and pigments. Within a clade, colors may not occupy the entire available space, and incorporating complementary colors may increase the contrast and efficacy of visual signals. Here, we describe plumage patterns in four ecologically and phylogenetically diverse bird families to test whether they possess complementary colors. We present evidence that plumage colors in each clade cluster along a line in tetrachromatic color space. Additionally, we present evidence that in three of these clades, this line contains colors on opposite sides of a line passing through the achromatic point (putatively complementary colors, presenting higher chromatic contrast). Finally, interspecific color variation over at least some regions of the body is not constrained by phylogenetic relatedness. By describing plumage patterns in four diverse lineages, we add to the growing body of literature suggesting that the diversity of bird visual signals is constrained. Further, we tentatively hypothesize that in at least some clades possessing bright colors, species-specific plumage patterns may evolve by swapping the distributions of a complementary color pair. Further research on other bird clades may help confirm whether these patterns are general across bird families.

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