Evidence for neither the compensation hypothesis nor the expensive-tissue hypothesis in Carassius auratus

2014 ◽  
Vol 64 (2) ◽  
pp. 177-187 ◽  
Author(s):  
Jiao Liu ◽  
Cai Quan Zhou ◽  
Wen Bo Liao
Keyword(s):  
Carassius Auratus ◽  
The Other ◽  
Testis Size ◽  
Left Testis ◽  
Brain Mass ◽  
Gonad Mass ◽  
Left And Right ◽  
Compensation Hypothesis ◽  
Gut Length ◽  
Expensive Tissue Hypothesis

In many taxa, the left and right testes often differ in size. The compensation hypothesis states that an increase in size of one testis can compensate for a reduced function in the other testis. Moreover, the expensive-tissue hypothesis predicts that an increase in investment of a metabolically costly tissue is offset by decreasing investment in the other metabolically costly tissues. Here we tested these two hypotheses in Carassius auratus, by analysing difference between left and right testes mass, and between brain mass and both gut length and gonad mass (testes mass in males and clutch mass in females). We found no difference between left and right testis mass and no correlations between relative testis size and body measurements. These findings suggest that the left testis cannot serve a compensatory role. Nonetheless, contrary to the predictions of the expensive-tissue hypothesis, brain mass was positively correlated with both gut length and gonad mass within each sex. This positive correlation between brain mass and other organs (gut, gonad and clutch tissues) suggests that organisms may compensate for substantial variation in investment in tissues without sacrificing other expensive tissues.

scholarly journals Intraspecific variation in testis asymmetry in birds: evidence for naturally occurring compensation

2009 ◽  
Vol 276 (1665) ◽  
pp. 2279-2284 ◽  
Author(s):  
Sara Calhim ◽  
Tim R. Birkhead
Keyword(s):  
Intraspecific Variation ◽  
Reproductive Investment ◽  
Quantitative Approach ◽  
The Other ◽  
Internal Organs ◽  
Trade Off ◽  
Naturally Occurring ◽  
Left And Right ◽  
Compensation Hypothesis

In many taxa, the left and right testes often differ in size. The compensation hypothesis states that one testis of the pair serves as a ‘back-up’ for any reduced function in the other and provides a mechanism to explain intraspecific variation in degree and direction of gonad asymmetry. Although testis asymmetry is common in birds, evidence for natural testis compensation is unknown. Using a novel quantitative approach that can be applied to any bilateral organ or structure, we show that testis compensation occurs naturally in birds and can be complete when one testis fails to develop. Owing to a recurrent risk of testis impairment and an evolutionary trade-off between natural and sexual selections acting on the arrangement of internal organs in species with abdominal and/or seasonal testes, compensation adds an important, but neglected, dimension to measures of male reproductive investment.

Rediagnosis of the squat lobster genus Gastroptychus Caullery, 1896, with a new genus Sternostylus and a new family Sternostylidae (Crustacea: Decapoda: Anomura: Chirostyloidea)

Zootaxa ◽  
2018 ◽  
Vol 4524 (1) ◽  
pp. 77 ◽  
Author(s):  
KEIJI BABA ◽  
SHANE T. AHYONG ◽  
KAREEN E. SCHNABEL
Keyword(s):  
Type Species ◽  
Anterior Margin ◽  
New Genus ◽  
Sister Group ◽  
Sensu Stricto ◽  
The Other ◽  
Squat Lobster ◽  
Terminal Spine ◽  
New Family ◽  
Left And Right

The chirostyloidean squat lobster genus Gastroptychus Caullery, 1896 is revised and is split into two genera: Gastroptychus sensu stricto (type species, Ptychogaster spinifer A. Milne-Edwards, 1880) and Sternostylus new genus (type species, Ptychogaster formosus Filhol, 1884). Gastroptychus sensu stricto, is restricted to nine species with a sternal plastron, at sternite 3, abruptly demarcated from the preceding sternites (excavated sternum) by a distinct step forming a well-defined transverse or concave anterior margin at the articulation with maxillipeds 3, the maxillipeds 3 widely separated, with the distal parts accommodated in the excavated sternum between the left and right maxillipeds 3 when folded, and the P2–4 dactyli with the terminal spine demarcated by a suture. Sternostylus new genus, represented by 12 species, has the sternite 3 anteriorly bluntly produced medially and steeply sloping anterodorsally to the anterior sternite, with a pair of spines directly behind the anterior margin, the left and right maxillipeds 3 adjacent, and the P2–4 dactyli ending in an indistinctly demarcated corneous spine. The above-mentioned characters of Gastroptychus are consistent with Chirostylidae sensu stricto. Published molecular phylogenies indicate, however, that Sternostylus is the sister group to all the other Chirostylidae, and is designated the type genus of a new family, Sternostylidae. 

scholarly journals Comparison of histometric and morphometric analyses of bone height in ligature-induced periodontitis in rats

2007 ◽  
Vol 21 (3) ◽  
pp. 216-221 ◽  
Author(s):  
Marilene Issa Fernandes ◽  
Eduardo José Gaio ◽  
Rui Vicente Oppermann ◽  
Pantelis Varvaki Rados ◽  
Cassiano Kuchenbecker Rosing
Keyword(s):  
Periodontal Disease ◽  
Morphometric Analysis ◽  
Wistar Rats ◽  
T Test ◽  
The Other ◽  
Limited Capacity ◽  
Height Measurement ◽  
Morphometric Analyses ◽  
Left And Right ◽  
Bone Height

The purpose of this study was to compare histologic and morphometric procedures of bone height measurement. Microscopic measurements are the most frequent methods in periodontal studies with animals, but have limited capacity to identify bone levels associated with both healthy tissues and periodontal disease. Ligatures were placed in the maxillary left second molars of 10 male 60-day-old Wistar rats for 30 days. Left and right maxillary sides of 5 rats were processed for histologic analysis (H), sectioned buccolingually, and stained with HE. The maxillae of the other 5 rats were defleshed and used for morphometric analysis (M). Histometric measurements from the cementoenamel junction to the bone crest were performed. Standardized photographs were used for morphometric analysis. The t test was used for dependent or independent samples (alpha = 0.05%). Distances from cementoenamel junction to bone crest were 0.95 ± 0.25 and 1.07 ± 0.30 mm for H and M, respectively. Buccal measurements were 0.92 ± 0.16 and 1.08 ± 0.35 mm for H and M. The values obtained using H and M for areas without ligatures were 0.44 ± 0.15 and 0.47 ± 0.11 mm for lingual measurements and 0.23 ± 0.08 and 0.41 ± 0.10 mm for buccal measurements. No significant differences were found between the two methods in the detection of bone height associated with the placement of ligatures in rats.

scholarly journals PHYSICAL DISTANCING ALARM SYSTEM BASED ON PROXIMITY SENSOR AND MICROCONTROLLER

2021 ◽  
Vol 4 (2) ◽  
pp. 79
Author(s):  
Elfi Yuliza ◽  
Riska Ekawita ◽  
Vionita Vionita ◽  
Muhammad Khafid Fauzi ◽  
Vera Fuspita Sari ◽  
...  
Keyword(s):  
System Performance ◽  
The Other ◽  
Alarm System ◽  
Best Effort ◽  
Interaction Distance ◽  
Measurement Results ◽  
Identity Card ◽  
Left And Right ◽  
Distance Sensor ◽  
User Friendly

Keeping an interaction distance between 1 to 2 m is one of the health protocols during the COVID-19 pandemic. This attempt was made to reduce the spread of the Coronavirus. On the other hand, this health protocol activity is often overlooked, whether intentionally or not. According to the mechanism of the Coronavirus spreading in the form of droplets that comes out during communication, sneezing, or coughing, maintaining distance can be the best effort to minimize the transmission of this virus. Therefore, the availability of a simple, accurate and user-friendly physical distancing alarm system could be a solution in the implementation of this health protocol. In this study, a prototype of a physical distancing alarm based on a distance sensor and a microcontroller in the form of an identity card was developed. Several steps are conducted in developing of this system, namely designing the instrumentation system and testing the performance of the system. System performance is tested through variations in the distance and angle of the objects. The measurement results show that the system can detect objects in front of the sensor up to a distance of 2.8m and an angle of  for a distance of 1m. The measurement using different angles of objects was performed for objects on the left and right sides of the sensor. In addition, a warning alarm will be on when the distance of the object exceeds the allowed distance.  

scholarly journals Intraspecific Hybridization Of Normal Pigmented And Albino Clarias Gariepinus From Yola And Katsina under Hatchery Condition

2021 ◽  
Vol 37 (2) ◽  
pp. 152-156
Author(s):  
L.U Onyia ◽  
I.J Ochokwu ◽  
V Robinson
Keyword(s):  
Clarias Gariepinus ◽  
Left Testis ◽  
Volume Percentage ◽  
Intraspecific Hybridization ◽  
Genetic Crosses ◽  
Reciprocal Hybrids ◽  
Highest Weight ◽  
Specific Hybridization ◽  
Left And Right ◽  
The Right

The study examined the reproductive indices of albino and normal pigmented Clarias gariepinus fish from Katsina (KT) and Yola (YY), carried out under hatchery condition. The experiment compared the fecundity, testes, milt volume, percentage fertilization and hatchability of albino (AA) and normal pigmented (NN) Clarias gariepinus from Katsina (KT) and Yola (YY). Normal pigmented C. gariepinus from Katsina (KT) had the highest number of eggs (229,240), followed by YY (127,250) and the least was recorded in the Albino (AA) (124,750). The weights and lengths of the left and right lobes as well as the volumes of the milt were quantified . However, KT had the highest weight and length of the right testis (18g and 5.7cm respectively) while AA had the highest weight, length of the left testis and milt volume (30g, 11cm and 8.4ml respectively). The least length and weight of the testes was observed in YY. Meanwhile, KT and YY had milt volumes of 4.0ml and 4.7ml, respectively. The highest percentage fertilization and hatchability were recorded in KT × KT (98.7% and 98.5% respectively) among the purebred, while KT × AA had the highest percentage fertilization and hatchability (98.4% and 97.3% respectively) in the reciprocal hybrids. The percentage fertilization and hatchability among the genetic crosses showed significant differences (p<0.05). The results deduced the essentiality of fish hybridization. Furthermore, crossing of broodstocks from different regions have showcased the contingency of acquiring fish seed of improved reproductive potentials in the reciprocal hybrids in the aspects of fecundity, fertilization, hatchability rate, testis quality and faster growth. Keywords: Albino, Fecundity, Intra-specific Hybridization, Normal pigmented, Testis

Sweden is Increasingly Loosing its Peculiarity (On Elections of 2010)

2011 ◽  
pp. 46-56
Author(s):  
I. Grishin
Keyword(s):  
Social Development ◽  
The Other ◽  
Political Life ◽  
Development Model ◽  
The Political ◽  
Social Development Model ◽  
Social Democrats ◽  
Parliamentary Elections ◽  
Political Force ◽  
Left And Right

The article analyses results of Swedish parliamentary elections in September 2010. The author regards them as another manifestation of the fact that Sweden is losing peculiarity of its social development model. This is a result of the end of an era of two-block party structure of the Riksdag (left and right centers) and of the domination of Social Democrats in the political life of the country. The new third political force – the party of Swedish Democrats which strongly opposes the other culture immigration – is detail regarded.

Democracy

2013 ◽  
Author(s):  
Anne Norton
Keyword(s):  
United States ◽  
Political Philosophy ◽  
John Rawls ◽  
Jacques Derrida ◽  
The United States ◽  
The Other ◽  
Left And Right ◽  
Anglo American

This chapter examines how the Muslim question is tied to the question of democracy. In his book Voyous (translated as Rogues), Jacques Derrida referred to the United States and Islam as the enemies of democracy. In particular, he called Islam “the other of democracy.” Only Islam, Derrida insisted, refuses democracy. Derrida was not the only scholar to have made that claim. His account echoes Samuel Huntington. John Rawls thought Islam so alien that he was obliged to treat it separately. There are countless scholars, left and right, Anglo-American and Continental, who have insisted that Islam is the other of democracy. The chapter suggests that political philosophy in the Muslim (but not simply Muslim) tradition offers visions of democracy, cosmopolitanism, immigration, and integration that are remarkably familiar.

scholarly journals Skull asymmetries in wild boar (Sus scrofa LINNAEUS, 1758)

2019 ◽  
Vol 56 (1) ◽  
pp. e150704
Author(s):  
Pere M. Parés-Casanova
Keyword(s):  
Environmental Factors ◽  
Wild Boar ◽  
Sus Scrofa ◽  
Age Groups ◽  
The Other ◽  
Directional Asymmetry ◽  
Two Dimensional ◽  
Entire Sample ◽  
Perfect Symmetry ◽  
Left And Right

Organisms can develop different kinds of asymmetry when deviations from expected perfect symmetry occur. Among others are fluctuating asymmetry (FA) and directional asymmetry (DA). FA represents small random differences between corresponding parts on the left and right sides of an individual in bilaterally paired structures. It is thought that FA reflects an organism’s ability to cope with genetic and environmental stress during growth. DA occurs whenever one side on the plane of symmetry develops more than the other side, and has a genetic component. In this research, we examined the expression of morphological symmetry in 38 skulls of different age groups of wild boar (Sus scrofa), on their ventral aspect, using two-dimensional coordinates of 27 landmarks. Analyses showed the presence of significant FA and DA in the entire sample, detecting also distinctive differences between age groups. The obtained results show that the shape differences in different age groups could reasonably be a consequence of a response to environmental factors for FA and a masticatory lateralization for DA.

Evolution of vertebrate brain size is associated with sexual traits

2020 ◽  
Vol 70 (4) ◽  
pp. 401-416
Author(s):  
Mao Jun Zhong ◽  
Long Jin ◽  
Jian Ping Yu ◽  
Wen Bo Liao
Keyword(s):  
Sexual Size Dimorphism ◽  
Brain Size ◽  
Finite Energy ◽  
Energy Resources ◽  
Testis Size ◽  
Vertebrate Brain ◽  
Sexual Traits ◽  
The Relationship ◽  
The Brain ◽  
Expensive Tissue Hypothesis

Abstract The expensive tissue hypothesis predicts a trade-off between investments in the brain and other energetically costly organs due to the costs associated with their growth and maintenance within the finite energy resources available. However, few studies address the strength of relationships between brain size and investments in precopulatory (ornaments and armaments) and postcopulatory (testes and ejaculates) sexual traits. Here, in a broad comparative study, we tested the prediction that the relationship between brain size and investment in sexual traits differs among taxa relative to the importance of sperm competition within them. We found that brain size was negatively correlated with sexual size dimorphism (SSD) in anurans and primates, and it tended to decrease with SSD in ungulates and cetaceans. However, brain size did not covary significantly with armaments (e.g., canine length, horn, antler, and muscle mass). Brain size was not correlated with postcopulatory sexual traits (testes and ejaculates). The intensity of covariance between brain size and precopulatory sexual traits decreased with increasing relative testis size.

Providing a human user artificial ability to control their eyes independently with various eye movement patterns

2012 ◽  
Vol 25 (0) ◽  
pp. 171-172
Author(s):  
Fumio Mizuno ◽  
Tomoaki Hayasaka ◽  
Takami Yamaguchi
Keyword(s):  
Eye Movements ◽  
Visual Perception ◽  
Control Systems ◽  
Eye Movement ◽  
Binocular Rivalry ◽  
Human Visual System ◽  
Visual Stimulation ◽  
The Other ◽  
Flexible Adaptation ◽  
Left And Right

Humans have the capability to flexibly adapt to visual stimulation, such as spatial inversion in which a person wears glasses that display images upside down for long periods of time (Ewert, 1930; Snyder and Pronko, 1952; Stratton, 1887). To investigate feasibility of extension of vision and the flexible adaptation of the human visual system with binocular rivalry, we developed a system that provides a human user with the artificial oculomotor ability to control their eyes independently for arbitrary directions, and we named the system Virtual Chameleon having to do with Chameleons (Mizuno et al., 2010, 2011). The successful users of the system were able to actively control visual axes by manipulating 3D sensors held by their both hands, to watch independent fields of view presented to the left and right eyes, and to look around as chameleons do. Although it was thought that those independent fields of view provided to the user were formed by eye movements control corresponding to pursuit movements on human, the system did not have control systems to perform saccadic movements and compensatory movements as numerous animals including human do. Fluctuations in dominance and suppression with binocular rivalry are irregular, but it is possible to bias these fluctuations by boosting the strength of one rival image over the other (Blake and Logothetis, 2002). It was assumed that visual stimuli induced by various eye movements affect predominance. Therefore, in this research, we focused on influenced of patterns of eye movements on visual perception with binocular rivalry, and implemented functions to produce saccadic movements in Virtual Chameleon.

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