scholarly journals VARIATION IN NEMEOPHILA PETROSA AT LAGGAN IN WESTERN ALBERTA

1895 ◽  
Vol 27 (4) ◽  
pp. 87-93
Author(s):  
Thomas E. Bean
Keyword(s):  
Early Stage ◽  
Relative Number ◽  
Great Majority ◽  
Common Occurrence ◽  
Night Temperature ◽  
Natural Conditions ◽  
Open Ground ◽  
Males And Females ◽  
Number Of Males

At 5,000 feet altitude, in the vicinity of Laggan, Nemeophila petrosaflies during July. This is one of our commoner moths, and appears to be the only bombycid of common occurrence in the district. Although occasionally round near timber 1ine, it is rare at that elevation. Under natural conditions only one flight occurs in the season, and larvæ from eggs of that flight hibernate principally at an early stage. In the house, with a warmer night temperature, larvæ resultant from the July flight will go to imago late in October instead of hibernating. Inthe wild environment, a second flight is prevented by the low night temperature. Petrosa frequents moist banks, ditches, margins of old roads, and open ground well supplied with plants. A great majority of the individuals seen in flight are males, the disparity in relative number of males and females observed resulting from the quieter disposition of the females. The males are very restless and readily take flight, thereby attracting observation.

scholarly journals A model of sexual selection and female use of refuge in a coercive mating system

2012 ◽  
Vol 279 (1741) ◽  
pp. 3209-3216
Author(s):  
Dessa Bokides ◽  
Yuan Lou ◽  
Ian M. Hamilton
Keyword(s):  
Total Population ◽  
Relative Number ◽  
Threshold Level ◽  
Male Harassment ◽  
Male Phenotype ◽  
Males And Females ◽  
Selection For ◽  
Coercive Mating ◽  
The Relationship ◽  
Number Of Males

In many non-monogamous systems, males invest less in progeny than do females. This leaves males with higher potential rates of reproduction, and a likelihood of sexual conflict, including, in some systems, coercive matings. If coercive matings are costly, the best female strategy may be to avoid male interaction. We present a model that demonstrates female movement in response to male harassment as a mechanism to lower the costs associated with male coercion, and the effect that female movement has on selection in males for male harassment. We found that, when females can move from a habitat patch to a refuge to which males do not have access, there may be a selection for either high, or low harassment male phenotype, or both, depending on the relationship between the harassment level of male types in the population and a threshold level of male harassment. This threshold harassment level depends on the relative number of males and females in the population, and the relative resource values of the habitat; the threshold increases as the sex ratio favours females, and decreases with the value of the refuge patch or total population. Our model predicts that selection will favour the harassment level that lies closest to this threshold level of harassment, and differing harassment levels will coexist within the population only if they lie on the opposite sides of the threshold harassment. Our model is consistent with empirical results suggesting that an intermediate harassment level provides maximum reproductive fitness to males when females are mobile.

Operational Sex Ratios in Seahorses

Behaviour ◽  
1994 ◽  
Vol 128 (1-2) ◽  
pp. 153-167 ◽  
Author(s):  
Amanda C.J. Vincent
Keyword(s):  
Relative Number ◽  
Reproductive Rate ◽  
Operational Sex Ratio ◽  
Laboratory Population ◽  
Sri Lankan ◽  
Males And Females ◽  
Male Pregnancy ◽  
Reproductive Rates ◽  
Number Of Males ◽  
Operational Sex Ratios

AbstractContrary to all expectations based on their male pregnancy, recent work shows that seahorses exhibit conventional sex roles in mating competition: male seahorses compete more to obtain eggs than females do to give their eggs away. This suggests that the operational sex ratio (OSR: the relative number of males and females available to mate) might be male-biased despite the length and limitations of male pregnancy. I here report a study of a laboratory population of the Sri Lankan seahorse Hippocampus fuscus. The OSR amongst mated seahorses is unbiased because males and females effectively have equal reproductive rates, although some evidence suggests that a female may have limited potential for a higher reproductive rate than her partner. In contrast, the OSR among mate-seeking seahorses is male-biased, because unmated (empty) males can prepare to mate more quickly and can remain ready to mate for longer than can unmated females. Thus, the OSR is male-biased in exactly that segment of the population which should compete for mates. These findings are compatible with the sexually monogamous mating pattern of many seahorse species.

scholarly journals Physiological, Biochemical, and Growth Parameters of Fogera Cattle Calves to Heat Stress during Different Seasons in Sub-Humid Part of Ethiopia

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1062
Author(s):  
Michael Abera ◽  
Yesihak Yusuf Mummed ◽  
Mitiku Eshetu ◽  
Fabio Pilla ◽  
Zewdu Wondifraw
Keyword(s):  
Heat Stress ◽  
Growth Parameters ◽  
Hematological Parameters ◽  
Average Temperature ◽  
High Weight Gain ◽  
Different Seasons ◽  
Current Production ◽  
Humidity Index ◽  
Males And Females ◽  
Number Of Males

Fogera cattle are among indigenous breeds of cattle in the northern part of Ethiopia. However, their response to heat stress (HS) under different seasonal variations has not been well investigated. This study was aimed to determine physiological, hematological, biochemical, and growth parameters of Fogera cattle calves to HS during dry season, short rainy, and long rainy. A total of 72 calves (24 for each season) that were 6 months of age with an equal number of males and females were evaluated for physiological, hematological, biochemical, and growth parameters. Daily ambient temperature (AT) and relative humidity (RH) were recorded two times per day during the study periods from which the daily average temperature–humidity index (THI) was calculated. The study revealed higher AT and THI during dry and short seasons while higher RH was observed during the long rainy season. Physiological parameters except rectal temperature were affected by the seasons. Hematological parameters were also affected by season except for packed cell volume. Biochemical and growth parameters were also significantly affected by the seasons. THI was positively related with physiological but negatively with growth parameters. Thus, the THI value of 66 can be considered as optimum for high weight gain and normal physiological response to HS in Fogera cattle calves under their current production system.

scholarly journals Фенотипическая пластичность в соотношении полов у Idotea baltica basteri (Crustacea, Isopoda) в Одесском заливе Черного моря

2014 ◽  
Vol 5 (1) ◽  
pp. 49-53 ◽  
Author(s):  
A. Y. Varigin
Keyword(s):  
Water Exchange ◽  
Sea Water ◽  
The Black Sea ◽  
Fouling Community ◽  
Gradual Decline ◽  
Idotea Baltica ◽  
Open Sea ◽  
Males And Females ◽  
Exchange Intensity ◽  
Number Of Males

The degree of phenotypic plasticity in the Idotea baltica basteri Audouin, 1827 (Crustacea, Isopoda) sex ratio of the fouling community in the Odessa bay of the Black Sea was determined. The ratio of males and females in three main phenotypes of I. baltica basteri, namely: uniformis, albafusca and lineata was found. Crustaceans were collected on the underwater surface of traverses, located in three sea districts with the different degrees of water exchange intensity with the open sea. Water depth at the wall of traverses ranged from 1 to2,5 m. In the first most opened district among the individuals of uniformis phenotype the ratio of males and females was equal to 1:4, that for albafusca – 1:1,3 and lineata – 1:1. In the second area with the release of drainage waters among the individuals of uniformis phenotype this ratio was equal to 1:4,5, while the albafusca and lineata figures were 1:1,5 and 1:1, accordingly. In the third region, with the most difficult water exchange, among the individuals of phenotypes the ratios of males and females were as follows: uniformis – 1:8, albafusca – 1:2, and lineata – 1:1. When moving from the opened to semi-enclosed area among the individuals of all phenotypes there was a gradual decline in the proportion of males and accordingly, increases of the proportion of females. The greatest number of males in all areas under study is observed among the individuals of lineata phenotype, and that of females – among the individuals of uniformis phenotype. It is found that monochromatic colored females prefer to stay in the shaded places among the seagrass beds and brightly colored males usually move actively along the outside of the substrata. 

scholarly journals Body Image Dissatisfaction in The Youth of India: And the Effects on Self-Esteem

2013 ◽  
Author(s):  
Bhawini Vasudeva
Keyword(s):  
Body Image ◽  
Body Shape ◽  
Body Image Dissatisfaction ◽  
Self Esteem ◽  
The Body ◽  
Short Version ◽  
Males And Females ◽  
The Impact ◽  
Sample Set ◽  
Number Of Males

The aim to conduct this research is to enlighten the impact of body image dissatisfaction on an individual’s self-esteem and to examine whether there is a gender difference in this case or not. There are a total of 220 numbers of participants, with equal number of males and females in the sample set. The tool that’d be using here is a modified short version of the Body Shape Questionnaire (BSQ) by Cooper et. Al. in the year in 1987 and The Rosenberg self-esteem scale by Morris Rosenberg (RSES) in the year 1965. The current research proved that whenever there’ll be higher body image dissatisfaction, it’ll result in less self-esteem. Other than that, it stated that females (M= 22.69 and SD= 3.64) have a higher mean score in body image dissatisfaction than and males (M=23.28 and SD= 3.6), therefore, the men have a higher mean score of self-esteem than females.

scholarly journals Weight and Body Composition Changes during the First Three Years of College

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Sareen S. Gropper ◽  
Karla P. Simmons ◽  
Lenda Jo Connell ◽  
Pamela V. Ulrich
Keyword(s):  
Body Fat ◽  
Significant Loss ◽  
Normal Weight ◽  
College Campuses ◽  
Fat Free Mass ◽  
Healthy Lifestyles ◽  
Freshman Year ◽  
Males And Females ◽  
Composition Changes ◽  
Number Of Males

Differences in weight, body mass index (BMI), percent and absolute body fat, fat-free mass, and waist circumference were investigated in a group of males and females during the first three years (from 2007 to 2010) of college. Significant three-year gains were observed for weight2.1±4.7 kg, BMI0.7±1.6 kg/m2, percent body fat2.7±3.3%, and fat mass2.3±3.5 kg. A significant loss of fat-free mass, −0.5 kg, was observed among females. Absolute gains in weight, BMI, and percent and absolute body fat were highest during the freshman year, followed by the junior year, and lowest during the sophomore year. Among the 70% of students gaining weight over the three years, weight gain averaged 4.3 kg. The numbers of females with over 30% body fat doubled, and the number of males with over 20% body fat increased fivefold. Initially 15% of students were classified as obese/overweight and 79% normal weight; by the end of the junior year, 24% were obese/overweight and 70% were normal weight. Efforts on college campuses to promote healthy lifestyles among its student population are needed throughout the college years.

Beberapa Aspek Reproduksi Siput Lambis lambis di Pesisir Perairan Yenusi, Biak

2016 ◽  
Vol 1 (3) ◽  
pp. 1
Author(s):  
Andriani Widyastuti ◽  
Ludi Parwadani Aji
Keyword(s):  
Sex Ratio ◽  
Management Strategies ◽  
Gonadal Development ◽  
Shell Size ◽  
Gonad Maturity ◽  
Males And Females ◽  
Over Exploitation ◽  
Number Of Males ◽  
Time Of Harvest

<strong>Some Aspects of Reproduction in Conch Lambis lambis of Yenusi Coastal Waters, Biak.</strong> Lambis lambis is a very popular conch species that has been harvested in all sizes encountered. This condition is very alarming because in the long term, its existence in nature will be reduced because there is no chance to reproduce naturally. This study aims to determine the sex ratio and gonad maturity levels of L. lambis in Yenusi waters, so the appropriate time of harvest can be arranged. Samples were collected every month from January to December 2013. Testing and histological analysis were performed in the laboratory. Samples collected were 99 individus with the number of males 45 individus and females 54 individus. The sex ratio of males and females was 1.0:1.2. Gonad maturity level found included all four stages of gonadal development, from TKG I to TKG IV. Gonadal development showed the process of formation and maturation, and the spawning occured throughout the year, with peak spawning in January until March 2013. The size of the shell length obtained ranged from 4.55 to 13.72 cm indicating over-exploitation. Due to the custom local where residents harvested the conches in all sizes found, sustainable management strategies are urgently needed, including moratorium period  when L. lambis is at the peak of spawning, and harvest should only be performed on adult individuals with a minimum shell size of 7 cm, while observing the thickness of the shell and marginal digitations have been formed. <br /><br />

Factors mediating inter-group encounters in savannah baboons (Papio cynocephalus ursinus)

Behaviour ◽  
2004 ◽  
Vol 141 (2) ◽  
pp. 197-218 ◽  
Author(s):  
Dawn Kitchen ◽  
Robert Seyfarth ◽  
Dorothy Cheney
Keyword(s):  
Dominance Hierarchy ◽  
Relative Number ◽  
Papio Cynocephalus ◽  
Male Behavior ◽  
Group Interactions ◽  
Opposing Group ◽  
Group Defense ◽  
Male Displays ◽  
The Individual ◽  
Number Of Males

AbstractInter-group encounters among baboons range from peaceful to aggressive. During 23 months we observed 110 inter-group interactions involving four groups of chacma baboons in the Okavango Delta, Botswana. Results supported the hypothesis that male behavior functions to prevent extra-group males from gaining access to sexually receptive females. Males were more likely to chase females in their own group when estrous females were present, and their chases targeted estrous females more often than expected. Males also chased members of the opposing group more when estrous females were present. When estrous females were absent, male displays were shorter in duration, involved fewer participants, were less intense, and were more likely to result in peaceful mingling between groups. The alpha male was the individual most actively involved in inter-group chases and displays, but males of all ranks participated, especially when they were in consort with a female. However, males did not cooperate in group defense. While behavior during encounters was affected by the presence of estrous females, the outcome of encounters was affected by location and rival group identity. Groups were more likely to approach and displace opponents in the core of their range and more likely to retreat in the periphery. Correcting for location, we also found some evidence for an inter-group dominance hierarchy based on the relative number of males.

scholarly journals The Development of the Species of Upogebia from Plymouth Sound

1919 ◽  
Vol 12 (1) ◽  
pp. 81-134 ◽  
Author(s):  
Gladys E. Webb
Keyword(s):  
Adult Stage ◽  
Distinct Species ◽  
The Body ◽  
Specific Character ◽  
Common Occurrence ◽  
Living State ◽  
Males And Females ◽  
Small Point

Upogebia deltura Leach and Upogebia stellata (Mont.) are both of common occurrence on the coasts of Devonshire and Cornwall, but in the adult stage they are not easily obtained, owing to their burrowing habits. The larvæ, however, are very common in the tow-nets, occurring throughout the year with the exception of the midwinter months, and are particularly plentiful from June to August. The two species are closely allied, and for some time it was believed that the differences between them might be merely sexual, and not specific (Bell 1853). They are now clearly recognised as separate and distinct species, and De Morgan (1910) has obtained males and females of both forms. Upogebia deltura Leach may be distinguished by its greater size, sometimes five or six inches in length when full-grown, as well as by its broad abdomen with soft abdominal pleura. The two joints of the chela on the first thoracic leg are almost equal in length. Upogebia stellata (Mont.) is an altogether smaller and more slender animal, seldom exceeding two and a half inches in length. The abdomen is narrower, and the fixed finger of the chela very much shorter than the dactylus. There is also a small point on the side of the carapace, just over the base of the second antenna, which has been established as a specific character by De Morgan (1910). In the living state the body of the animal is covered with orange-red spots (hence its name stellata), while Upogebia deltura Leach is of a uniform dirty cream colour.

scholarly journals A novel seed baiting technique for the epiphytic orchid Rhynchostele cervantesii, a means to acquire mycorrhizal fungi from protocorms

Lankesteriana ◽  
2015 ◽  
Vol 15 (1) ◽  
Author(s):  
Jesús Bernardo Cruz-Higareda ◽  
Bárbara Susana Luna-Rosales ◽  
Amadeo Barba-Álvarez
Keyword(s):  
Mycorrhizal Fungi ◽  
Pure Culture ◽  
Water Retention ◽  
Early Stage ◽  
Natural Conditions ◽  
Epiphytic Orchid ◽  
Stage Of Development ◽  
Mature Seeds

We developed a new and novel seed baiting technique sowing mature seeds of the epiphyitic orchid Rhynchostele cervantesii under natural conditions, We introduced a sponge in each package that may serve as a reservoir for water retention to benefit germination; In three of 22 packets we found protocorms in an early stage of development, six of wich were of sufficient size to warrant fungal isolations; Nine strains were isolated in pure culture and were inoculated on seeds and protocorms under in vitro conditions. 

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