scholarly journals Biometric sexual and ontogenetic dimorphism on the marine catfish Genidens genidens (Siluriformes, Ariidae) in a tropical estuary

2017 ◽  
Vol 43 (5) ◽  
pp. 895-903
Author(s):  
Larissa G. Paiva ◽  
Luana Prestrelo ◽  
Kiani M. Sant'Anna ◽  
Marcelo Vianna
Keyword(s):  
Sexual Dimorphism ◽  
Morphological Difference ◽  
Body Measurements ◽  
Guanabara Bay ◽  
Sex Dimorphism ◽  
Total Length ◽  
Maturity Stages ◽  
Males And Females ◽  
Adipose Fin ◽  
Eye Depth

This paper aims to study the ontogenetic sexual dimorphism of Genidens genidens in Guanabara Bay, southeastern coast of Brazil. Altogether 378 specimens were anayzed (233 females and 145 males) with total length ranging from 13.3 to 43.5 cm. Specimens were measured for 12 body measurements, sex was identified and maturity stages were recorded and classified. Pearson’s linear correlation reveled a significant positive correlation between total length and all other body measures, except for base adipose fin, mouth depth and eye depth for immature females. Analyses nested PERMANOVA desing showed significant differences between maturity stages for each sex, between sexes considering or not maturity stages, indicating a variation in morphometric characteristics driven by sexual dimorphism. Differences among all maturity stages were also found, indicating an ontogenetic morphological difference. But immature individuals didn’t differ between sexes indicating that differentiation patterns starts with sexual development. The most important measures differing males and females were related to head characteristics, which appears to be key parameters to evaluate sexual differences. Due to male incubation of fertilized eggs and juvenile individuals <59 mm in their oral cavity, head measures are proposed to be sex dimorphism not related to reproduction, but with post reproductive fase due to ecological and biological needs.  [L1]Modificated  as suggested by Reviewer E.

scholarly journals Morphometric characters and their relationship in estuarine catfish

1970 ◽  
Vol 6 (2) ◽  
pp. 349-353 ◽  
Author(s):  
M Begum ◽  
Abdullah Al-Mamun ◽  
ML Islam ◽  
MJ Alam
Keyword(s):  
Sexual Dimorphism ◽  
Linear Relationship ◽  
Standard Length ◽  
Head Length ◽  
Pectoral Fin ◽  
Morphometric Characters ◽  
Total Length ◽  
Length Standard ◽  
Eye Diameter ◽  
Males And Females

The morphometric observations were made on total length, standard length, pre-caudal length, head length, eye diameter and depth of body at pectoral fin base of estuarine catfish M. gulio. Males and females showed homogeneity in characters. A linear relationship was found between total length and morphometric characters. Regression of length and weight did not deviate significantly from cube law indicating isometric growth. The fish exhibited sexual dimorphism. Keywords: Morphometric characters; Estuarine catfish; Mystus gulio DOI: 10.3329/jbau.v6i2.4833 J. Bangladesh Agril. Univ. 6(2): 349-353, 2008

scholarly journals Hemigrammus tocantinsi: a new species from the upper rio Tocantins basin, Central Brazil (Characiformes: Characidae)

2010 ◽  
Vol 8 (2) ◽  
pp. 247-254 ◽  
Author(s):  
Fernando R Carvalho ◽  
Vinicius A Bertaco ◽  
Fernando C Jerep
Keyword(s):  
New Species ◽  
Sexual Dimorphism ◽  
Body Measurements ◽  
Central Brazil ◽  
Longitudinal Stripe ◽  
Fin Rays ◽  
Adipose Fin ◽  
A New Species

Hemigrammus tocantinsi is described from the upper rio Tocantins basin, Chapada dos Veadeiros, Goiás State, Central Brazil. The new species differs from its congeners by the presence of 15-17 branched anal-fin rays, longitudinal stripe relatively narrow anteriorly and wider posteriorly, and one or two maxillary teeth. Sexual dimorphism of the new species is characterized by differences among the color in life, adipose-fin origin, body measurements, in addition to presence of bony hooks in the anal and pelvic fins of males.

Biometric relationships of the spotted lobster, Panulirus echinatus, from Tamandaré coastal reefs, Pernambuco State, Brazil

2009 ◽  
Vol 89 (8) ◽  
pp. 1601-1606 ◽  
Author(s):  
Aline do Vale Barreto ◽  
Maria de Lourdes Zani-Teixeira ◽  
Carlos Tassito Correa Ivo ◽  
Mario Katsuragawa
Keyword(s):  
Carapace Length ◽  
Total Weight ◽  
Body Measurements ◽  
Allometric Growth ◽  
Male And Female ◽  
Total Length ◽  
Males And Females

Biometric relationships were recorded for 2431 male and female Panulirus echinatus sampled at Tamandaré coastal reefs, Pernambuco, Brazil. The following body measurements were taken: carapace length and width, abdomen length and width, total length, third and fifth pereiopod length, cephalothorax–abdomen and total weight. Twelve relationships were studied to compare the biometric characteristics of males and females. Eleven of them showed difference between the sexes. Comparing sexes with the same carapace length, males have a heavier cephalothorax and longer third and fifth pereiopods than females, whereas females are longer, wider, and have a heavier abdomen than males. For genders with the same total length, males are heavier and have a longer carapace than females, while females have a larger abdomen. For genders with the same abdomen length, males have a heavier abdomen than females. The relationships TWg/TL and AWg/AL showed positive allometric growth for the males. All other relationships involving weight, presented negative allometric growth for both sexes.

Observation on the breeding biology of Polypedates teraiensis (Dubois, 1987) (Amphibia: Rhacophoridae)

2017 ◽  
Vol 17 (1) ◽  
pp. 25-32
Author(s):  
Jacinta Lalchhanhimi ◽  
Lalremsanga H.T.
Keyword(s):  
Sexual Dimorphism ◽  
Breeding Season ◽  
Sound Production ◽  
Reproductive Function ◽  
Breeding Biology ◽  
Tree Frog ◽  
University Campus ◽  
Morphometric Measurements ◽  
Advertisement Calls ◽  
Males And Females

The breeding biology of tree frog, Polypedates teraiensis was studied during the breeding season at Mizoram University Campus. It was found that sound production by male during the breeding season was primarily a reproductive function and advertisement calls attract females to the breeding areas and announce other males that a given territory is occupied. The aim of this study was to provide the detailed information on the breeding behaviour and the advertisement calls of Polypedates teraiensis. The morphometric measurements of the amplecting pairs (males and females) for sexual dimorphism along with clutch sizes were also studied.

Sexual Dimorphism among the Kathmandu University Students Assessed by Anthropometric Studies

2018 ◽  
Vol 9 (05) ◽  
pp. 20469-20472
Author(s):  
Shakya R ◽  
Bhattacharya SC ◽  
Shrestha R
Keyword(s):  
Young Adults ◽  
Sexual Dimorphism ◽  
Young Adult ◽  
University Students ◽  
Plastic Surgery ◽  
Age Group ◽  
Adult Age ◽  
Clinically Normal ◽  
Crime Detection ◽  
Males And Females

Objectives: To observe the sexual dimorphism among the young adult age group ranging from 18-21 years, of Kathmandu University students by measuring craniofacial circumference and canthal distances. Rationale of the study: These data could be useful for establishing the craniofacial standards and adds an implementation on plastic surgery, crime detection as well as in the industrial field. Method: 300 clinically normal students of Kathmandu University aged between 18-21 years were examined for the study. Fronto-occipital circumference, outer and inner canthal distances were measured. All the parameters were compared between males and females. Result: The cranial circumference as well as the inner and outer canthal distance in males was found to be significantly higher as compared to the females. Conclusion: The results concluded that sexual dimorphism remarkably exists in young adults of Kathmandu University students.

scholarly journals Sexual dimorphism in the long-term stability (10 years) of skeletal Class III treatment

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Natalia Tejedor ◽  
Conchita Martín ◽  
José Antonio Alarcón ◽  
María Dolores Oteo-Calatayud ◽  
Juan Carlos Palma-Fernández
Keyword(s):  
Sexual Dimorphism ◽  
Class Iii ◽  
Class Iii Malocclusion ◽  
Skeletal Class ◽  
Term Stability ◽  
Long Term Stability ◽  
Fixed Appliances ◽  
Males And Females ◽  
Class Iii Treatment

Abstract Background Class III malocclusion is associated with high sexual dimorphism, especially in individuals older than 13 years of age, with significant differences in growth between males and females during the pubertal and postpubertal stages, and in adulthood. The aim of this research was to examine differences between males and females in long-term stability (10 years) of treatment for skeletal Class III malocclusion. Methods Thirty patients (15 males and 15 females) with skeletal Class III malocclusion, who had been treated with rapid maxillary expansion (RME) combined with face mask protraction followed by fixed appliances, were selected sequentially. Thirty patients (15 males and 15 females) with skeletal Class I and mesofacial patterns treated only with fixed appliances for dental problems served as the control group. Differences between groups and sexes were evaluated using lateral cephalograms taken at the start of treatment (T0), immediately after the end of treatment (T1), and after 10 years (T2). The long-term treatment success rate was calculated. Results Ten years after Class III treatment, overjet and overbite relapse occurred similarly in females (− 0.68 ± 0.7 mm; − 0.38 ± 0.75 mm, respectively) and males (− 1.09 ± 1.47 mm; − 0.64 ± 0.9 mm, respectively); the ANB angle and Wits appraisal became significantly more negative in males (− 1.37 ± 1.06°; − 2.7 ± 2.53 mm) than in females (− 0.18 ± 1.26°; − 0.46 ± 1.94 mm). The success rate was 73.3% in males and 80% in females. Conclusions Significant differences in the long-term stability of Class III treatment outcomes have been found between males and females, with a larger skeletal Class III relapse and lower long-term success rates in males.

Alaskan moose measurements and weights and measurement–weight relationships

1978 ◽  
Vol 56 (2) ◽  
pp. 298-306 ◽  
Author(s):  
Albert W. Franzmann ◽  
Robert E. LeResche ◽  
Robert A. Rausch ◽  
John L. Oldemeyer
Keyword(s):  
Growth Rate ◽  
Blood Parameters ◽  
Field Application ◽  
Regression Equations ◽  
Body Measurements ◽  
Male And Female ◽  
Total Length ◽  
Chest Girth ◽  
Hind Foot ◽  
Alces Alces Gigas

A total of 1329 Alaskan moose (Alces alces gigas) were measured for total length, 1340 for chest girth, 1317 for hind foot, 618 for shoulder height, and 1219 for ear length. Five hundred and four moose were weighed. These data were classified by sex, age, month sampled, and location. Growth rates were plotted and discussed. No morphometric differences were detected by sex and location classifications up to age 36 months. Location differences were detected which corresponded to general condition, productivity, and condition related blood parameters of the populations. Seasonal weight patterns demonstrated increases from 21 to 55% from spring to late fall. Measurements, particularly total lengths, were better indicators of growth rate than were weights. All body measurements were significantly correlated with weight: total length, r (correlation coefficient) = 0.94; chest girth, r = 0.90; shoulder height, r = 0.87; and hind foot, r = 0.81. Combined sex regression equations were derived because the slight differences between the male and female regression lines were unimportant in field application. These regression equations were as follows: weight (kilograms) = −239.7 + 2.07(total length); weight (kilograms) = −245.3 + 3.14(chest girth).

scholarly journals Safe sex: male–female coalitions and pre-copulatory mate-guarding in a fiddler crab

2009 ◽  
Vol 6 (2) ◽  
pp. 180-182 ◽  
Author(s):  
Richard N. C. Milner ◽  
Michael D. Jennions ◽  
Patricia R. Y. Backwell
Keyword(s):  
Sexual Dimorphism ◽  
Reproductive Success ◽  
Observational Data ◽  
Fiddler Crab ◽  
Lower Boundary ◽  
Mate Guarding ◽  
Maintenance Costs ◽  
Boundary Maintenance ◽  
Uca Annulipes ◽  
Males And Females

In fiddler crabs both males and females defend territories that are essential for survival. Given pronounced sexual dimorphism in weaponry, how do weaponless females defend their territory from well-armed males? Using observational data and two simple experiments, we test whether male Uca annulipes protect their female neighbours from conspecific intruders. We show that males defend their female neighbours against male but not female intruders. We also show that females sometimes mate with their immediate neighbours. Male defence of female neighbours appears to represent both pre-copulatory mate-guarding and a territorial coalition. Males who ensure that their neighbour remains female could benefit through increased opportunity for future reproductive success and lower boundary maintenance costs.

Sex differences in white adipose tissue expansion: emerging molecular mechanisms

2021 ◽  
Vol 135 (24) ◽  
pp. 2691-2708
Author(s):  
Simon T. Bond ◽  
Anna C. Calkin ◽  
Brian G. Drew
Keyword(s):  
Sex Differences ◽  
Sexual Dimorphism ◽  
Gene Networks ◽  
Large Scale ◽  
Molecular Mechanisms ◽  
Association Studies ◽  
Tissue Expansion ◽  
Economic Systems ◽  
Genomic Association ◽  
Males And Females

Abstract The escalating prevalence of individuals becoming overweight and obese is a rapidly rising global health problem, placing an enormous burden on health and economic systems worldwide. Whilst obesity has well described lifestyle drivers, there is also a significant and poorly understood component that is regulated by genetics. Furthermore, there is clear evidence for sexual dimorphism in obesity, where overall risk, degree, subtype and potential complications arising from obesity all differ between males and females. The molecular mechanisms that dictate these sex differences remain mostly uncharacterised. Many studies have demonstrated that this dimorphism is unable to be solely explained by changes in hormones and their nuclear receptors alone, and instead manifests from coordinated and highly regulated gene networks, both during development and throughout life. As we acquire more knowledge in this area from approaches such as large-scale genomic association studies, the more we appreciate the true complexity and heterogeneity of obesity. Nevertheless, over the past two decades, researchers have made enormous progress in this field, and some consistent and robust mechanisms continue to be established. In this review, we will discuss some of the proposed mechanisms underlying sexual dimorphism in obesity, and discuss some of the key regulators that influence this phenomenon.

scholarly journals Reproductive biology of Sympterygia bonapartii (Chondrichthyes: Rajiformes: Arhynchobatidae) in San Matías Gulf, Patagonia, Argentina

2017 ◽  
Vol 15 (1) ◽  
Author(s):  
María L. Estalles ◽  
María R. Perier ◽  
Edgardo E. Di Giácomo
Keyword(s):  
Sexual Dimorphism ◽  
Reproductive Biology ◽  
Early Spring ◽  
Egg Laying ◽  
Reproductive Pattern ◽  
Reproductive Parameters ◽  
Egg Capsules ◽  
Northern Patagonia ◽  
Total Length

ABSTRACT This study estimates and analyses the reproductive parameters and cycle of Sympterygia bonapartii in San Matías Gulf, northern Patagonia, Argentina. A total of 827 males and 1,299 females were analysed. Males ranged from 185 to 687 mm of total length (TL) and females from 180 to 742 mm TL. Sexual dimorphism was detected; females were larger, heavier, exhibited heavier livers, wider discs and matured at lager sizes than males. Immature females ranged from 180 to 625 mm TL, maturing females from 408 to 720 mm TL, mature ones from 514 to 742 mm TL and females with egg capsules from 580 to 730 mm TL. Immature males ranged from 185 to 545 mm TL, maturing ones from 410 to 620 mm TL and mature males from 505 to 687 mm TL. Size at which 50% of the skates reached maturity was estimated to be 545 mm TL for males and 594 mm TL for females. According to the reproductive indexes analysed, S. bonapartii exhibited a seasonal reproductive pattern. Mating may occur during winter-early spring and the egg-laying season, during spring and summer.

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