Functional aspects of maternal aggression in mammals

1992 ◽  
Vol 70 (6) ◽  
pp. 1069-1077 ◽  
Author(s):  
Dario Maestripieri

Evidence from several species of mammals suggests that the observed increase in female aggressiveness during lactation is aimed at protecting offspring from conspecifics. Whereas in rodents maternal aggression seems to constitute a deterrent against infanticidal behavior by adult males and females, in pinnipeds and primates its most likely function is to protect infants from general harassment by other individuals. Maternal aggression may also be involved in mate selection and function as a spacing mechanism. As an offspring defence behavior, maternal aggression can be considered a form of parental investment. As such, predictions can be made about its intensity in relation to the net effects it has on parental fitness. The functional aspects of maternal aggression suggest that this behavior should be analyzed in relation to other patterns of maternal care and investment in the offspring.

1983 ◽  
Vol 61 (8) ◽  
pp. 1733-1743 ◽  
Author(s):  
Richard A. Wishart

The American wigeon (Anas americana) was studied during winter in southwestern British Columbia and on its breeding grounds in south-central Saskatchewan. Sex ratios ranged from 52.4 to 59.6% males. Wigeons courted in small groups but not all birds did so concurrently. However, by April all females were paired. Some winter pair bonds were temporary and observations of wild birds as well as a group of captives indicated that males and females exhibited mate preferences. Persistent aggression, dominance, mate attentiveness, and the performance of functional displays and aerial chases by males were important in acquiring a mate. Adult males in full alternate plumage tended to pair earliest. Those unable to obtain a mate were generally smaller and had lower protein and lipid reserves. These characteristics with which mate choice was correlated were also those which were important during nesting later on.


2019 ◽  
Vol 53 (4) ◽  
pp. 325-334
Author(s):  
V. N. Peskov ◽  
N. A. Petrenko ◽  
V. Yu. Reminnyi

Abstract We study size-at-age and sexual variability of morphometric characteristics of the marsh frog. According to the size of the body, males were divided into three size-age groups (juvenis, subadultus, adultus), females — into four groups (juvenis, subadultus, adultus, adultus-I). We found that the chronological age of frogs (skeletochronology) does not always correspond to their biological age (size and proportions of the body). We noted that the semi-adult males are reliably larger than females by mean values of 26 studied morphometric characters. Males and females of “adultus” group do not differ by linear body size, significant differences were found in body proportions (7 characters). For the females of “adultus-I” group, the mean values of 26 characters are significantly larger than for “adultus” males. The results of our study showed that with the age of the marsh frog, the level of exhibition, directionality and structure of morphometric sex differences changes.


2020 ◽  
Vol 6 (38) ◽  
pp. eaaz5746
Author(s):  
Catherine Crockford ◽  
Liran Samuni ◽  
Linda Vigilant ◽  
Roman M. Wittig

Humans are unusual among animals for continuing to provision and care for their offspring until adulthood. This “prolonged dependency” is considered key for the evolution of other notable human traits, such as large brains, complex societies, and extended postreproductive lifespans. Prolonged dependency must therefore have evolved under conditions in which reproductive success is gained with parental investment and diminished with early parental loss. We tested this idea using data from wild chimpanzees, which have similarly extended immature years as humans and prolonged mother-offspring associations. Males who lost their mothers after weaning but before maturity began reproducing later and had lower average reproductive success. Thus, persistent mother-immature son associations seem vital for enhancing male reproductive success, although mothers barely provision sons after weaning. We posit that these associations lead to social gains, crucial for successful reproduction in complex social societies, and offer insights into the evolution of prolonged dependency.


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 313-313
Author(s):  
Brianne Olivieri-Mui ◽  
Sandra Shi ◽  
Ellen McCarthy ◽  
Dae Kim

Abstract Frailty may differentially impact how older adult males and females perceive sexual functioning, an important part of well-being. We assessed the level of frailty (robust, pre-frail, frail) for anyone with data on 11 sexual functioning questions asked in wave 2 of the National Social Life, Health, and Aging Project, 2010-2011 (n=2060). Questions covered five domains: overall sexual function (OSF), sexual function anxiety (SFA), changes in sexual function (CSF), erectile/vaginal dysfunction (EVD), and masturbation. Logistic regression identified sex differences in frailty and reporting worse sexual functioning. Linear regression predicted the number of domains reported as worse. Among males (n=1057), pre-frailty meant higher odds of reporting SFA (OR 1.8 95%CI 1.2-6.6), CSF (OR 1.7 95%CI 1.1-2.7), and EVD (OR 1.5 95%CI 1.0-2.2). Among females (n=1003), there was no difference in reporting by frailty. Females were more likely to report worse OSF (Robust: OR 7.4, 95%CI 4.8-11.4; Pre-frail: OR 6.2, 95%CI 3.9-9.9; Frail: OR 3.4 95%CI 1.7-6.6), but less likely to report SFA (Robust OR .3, 95%CI .2-.5; Pre-frail OR .2, 95%CI .1-.3; Frail OR .2 95%CI .1-.3). Pre-frail and frail females reported fewer domains as worse (Pre-frail coefficient -0.21 SE 0.09, Frail -0.43 SE 0.14). As frailty worsened, males reported more domains as worse (Pre-frail 0.24 SE 0.07, Frail 0.29 SE 0.08). Self-reported sexual functioning differs by sex at all levels of frailty, and reporting by males, but not females, changes with frailty. Providers should be aware that sexual functioning is of importance to both sexes despite varying degrees of frailty.


Rheumatology ◽  
2021 ◽  
Vol 60 (Supplement_1) ◽  
Author(s):  
Brona Dinneen ◽  
David Heath ◽  
Mohammed Tauseef Ghaffar ◽  
Miriam O'Sullivan ◽  
Carmel Silke ◽  
...  

Abstract Background/Aims  There is currently no consensus regarding sex-related differences in pain intensity and functional abilities among patients with hand osteoarthritis (OA). In this study we determine sex-related differences in pain intensity and functional ability among patients with hand OA, as assessed by a self-report questionnaire and by performance-based tests. Methods  Using the AUSCAN tool for symptom and functional assessment of hand OA with dynamometry we prospectively accessed patients meeting the ACR criteria for hand osteoarthritis. Using this analysis, assessments of pain and function were compared in male and female patients. The outcome measures included self-reported pain measures, functional assessment and dynamometry measures. Results  The study population included 106 patients (90 females and 16 males) with a mean age of males 48.44 (7.48) and females 52.67 (9.43). All patients with symptomatic hand osteoarthritis meeting ACR Criteria. When accessing difference between sexes, men were found to be significantly heavier (p = 0.003) and have greater grip and pinch strength.As part of function and pain assessments there was a significant correlation between difficulty with fine motor skills such as difficulty doing buttons, difficulty when doing jewellery, or peeling vegetables associated with pain when turning objects e.g. doorknobs, taps and faucets for men in comparison to women. Difficulty in these fine motor skills also correlated with stiffness on wakening and pain on lifting heavy objects regardless of sex. A Mann-Whitney U test was run on 106 participants to determine if there were differences in pain or functional scores between males and females. This reviled Median score for males () and females () was statistically significantly different,There were sex differences noted in the correlation associated with pain with rotational movements e.g. turning objects and functional difficulty with fine motor movements including difficulty when doing up buttons ( Males r(14) = -0.109, p = 0.698, Females r(88) =0.489, p = <0.01 value.= ), difficulty when doing jewellery ( Males r(14) =-0.265, p = 0.339.= Females r(88) = 0.570, p = <0.01) , difficulty peeling vegetables ( Males r(14) = -0.207, p = 0.458 Females r(88) = 0.519, <0.01 ) Conclusion  The results demonstrate the presence of sex differences in patients suffering from hand osteoarthritis self-reported functional ability and pain scales. These differences indicate the need for further studies to explore the mechanisms of hand OA and to understanding the specific impact of gender on the development and progression of disease. With further understanding we can obtain the proper strategy to provide better individualised treatment. It also highlights that rehabilitation programs should consider these differences and each patients’ performance limitations in order to address the specific needs of each individual patient. In doing so, improved pain and functional status will improve morbidity in hand OA Disclosure  B. Dinneen: None. D. Heath: None. M. Ghaffar: None. M. O'Sullivan: None. C. Silke: None. B. Whelan: None.


2018 ◽  
Vol 7 (18) ◽  
Author(s):  
Matthew Chung ◽  
Laura Teigen ◽  
Silvia Libro ◽  
Robin E. Bromley ◽  
Nikhil Kumar ◽  
...  

Here, we present a comprehensive transcriptomics data set of Brugia malayi, its Wolbachia endosymbiont wBm, and its vector host. This study samples from 16 stages across the entire B. malayi life cycle, including stage 1 through 4 larvae, adult males and females, embryos, immature microfilariae, and mature microfilariae.


2003 ◽  
Vol 30 (3) ◽  
pp. 281 ◽  
Author(s):  
David S. Dique ◽  
Jim Thompson ◽  
Harriet J. Preece ◽  
Deidré L. de Villiers ◽  
Frank N. Carrick

Koala dispersal was investigated as part of a detailed ecological study of a nationally significant koala population located 20 km south-east of Brisbane, Queensland. From 1996 to 2000, 195 koalas from three sites were captured and fitted with radio-collars. A total of 40 koalas (23 males and 17 females) dispersed from these sites. Most (93%) dispersing individuals were 20–36 months of age. Three adult females (more than 36 months old) dispersed and no adult males dispersed during the study. A significantly higher proportion of young males dispersed than females. Dispersal occurred between June and December, with most dispersal of males commencing in July and August and that of females commencing between September and November prior to, and early in, the annual breeding season. The mean straight-line distance between the natal and breeding home ranges for males and females was similar and was measured at 3.5 km (range 1.1–9.7 km) and 3.4 km (range 0.3–10.6 km) respectively. Dispersing males and females tended to successfully disperse south and west of their natal home ranges and were generally unable to successfully disperse to urban areas within the study area, as a high proportion of the mortality of dispersing koalas was associated with attacks by domestic dogs and with collisions with vehicles on roads. Information from other studies indicates that most young koalas disperse from their natal areas. It is likely that the social behaviour and mating systems of koala populations provide mechanisms for young koalas to disperse. The potential role of dispersal in the dynamics of regional koala populations is discussed.


2015 ◽  
Vol 90 (2) ◽  
pp. 186-198 ◽  
Author(s):  
S.V. Malysheva

AbstractOzolaimus linstowin. sp. is described from the large intestine ofIguana iguanaLinnaeus, 1758 from Mexico. The present species can be easily distinguished fromO. megatyphlonandO. cirratusby the presence of a long and slender pharynx not divided into sections, more similar to the remaining two species,O. monhysteraandO. ctenosauri. Ozolaimus linstowin. sp. can be differentiated fromO. monhysteraby the shorter spicule length and smaller body size of both males and females. Males ofO. linstowin. sp. are morphologically close to those ofO. ctenosauri, but females possess a markedly smaller body size and differ in the organization of the oral cuticular armature. Adult males ofO. linstowin. sp. bear some characteristic features of the J3 juvenile morphology in terms of the cuticular organization of the oral and buccal capsule. Phylogenetic analysis ofO.linstowin. sp. using partial small subunit (SSU) and D2–D3 large subunit (LSU) rDNA shows relationships with several Oxyuridae genera.


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