scholarly journals A long post-reproductive lifespan is a shared trait among genetically distinct killer whale populations

2021 ◽  
Author(s):  
Mia Nielsen ◽  
Samuel Ellis ◽  
Jared Towers ◽  
Thomas Doniol-Valcroze ◽  
Daniel Franks ◽  
...  
Keyword(s):  
Social Structure ◽  
Killer Whale ◽  
Demographic Data ◽  
Reproductive Period ◽  
Substantial Variation ◽  
Killer Whales ◽  
Reproductive Conflict ◽  
Demographic Patterns ◽  
General Prediction

The extended female post-reproductive lifespan found in humans and some toothed whales remains an evolutionary puzzle. Theory predicts demographic patterns resulting in increased female relatedness with age (kinship dynamics) can select for a prolonged post-reproductive lifespan due to the combined costs of inter-generational reproductive conflict and benefits of late-life helping. Here we test this prediction using >40 years of longitudinal demographic data from the sympatric yet genetically distinct killer whale ecotypes: resident and Bigg’s killer whales. The female relatedness with age is predicted to increase in both ecotypes, but with a less steep increase in Bigg’s due to their different social structure. Here, we show that there is a significant post-reproductive lifespan in both ecotypes with >30% of adult female years being lived as post-reproductive, supporting the general prediction that an increase in local relatedness with age predisposes the evolution of a post-reproductive lifespan. Differences in the magnitude of kinship dynamics however, did not influence the timing or duration of the post-reproductive lifespan with females in both ecotypes terminating reproduction before their mid-40s followed by an expected post-reproductive period of ~20 years. Our results highlight the important role of kinship dynamics in the evolution of a long post-reproductive lifespan in long-lived mammals, while further implying that the timing of menopause may be a robust trait that is persistent despite substantial variation in demographic patterns among population.

scholarly journals Postreproductive killer whale grandmothers improve the survival of their grandoffspring

2019 ◽  
Vol 116 (52) ◽  
pp. 26669-26673 ◽  
Author(s):  
Stuart Nattrass ◽  
Darren P. Croft ◽  
Samuel Ellis ◽  
Michael A. Cant ◽  
Michael N. Weiss ◽  
...  
Keyword(s):  
Life History ◽  
Inclusive Fitness ◽  
Killer Whale ◽  
Mammalian Species ◽  
Life History Trait ◽  
Killer Whales ◽  
Reproductive Conflict ◽  
Significant Survival ◽  
Fitness Benefits ◽  
Difficult Times

Understanding why females of some mammalian species cease ovulation prior to the end of life is a long-standing interdisciplinary and evolutionary challenge. In humans and some species of toothed whales, females can live for decades after stopping reproduction. This unusual life history trait is thought to have evolved, in part, due to the inclusive fitness benefits that postreproductive females gain by helping kin. In humans, grandmothers gain inclusive fitness benefits by increasing their number of surviving grandoffspring, referred to as the grandmother effect. Among toothed whales, the grandmother effect has not been rigorously tested. Here, we test for the grandmother effect in killer whales, by quantifying grandoffspring survival with living or recently deceased reproductive and postreproductive grandmothers, and show that postreproductive grandmothers provide significant survival benefits to their grandoffspring above that provided by reproductive grandmothers. This provides evidence of the grandmother effect in a nonhuman menopausal species. By stopping reproduction, grandmothers avoid reproductive conflict with their daughters, and offer increased benefits to their grandoffspring. The benefits postreproductive grandmothers provide to their grandoffspring are shown to be most important in difficult times where the salmon abundance is low to moderate. The postreproductive grandmother effect we report, together with the known costs of late-life reproduction in killer whales, can help explain the long postreproductive life spans of resident killer whales.

Globalization, Citizenship, and Subjectivity in Self Construction

2020 ◽  
Vol 10 ◽  
pp. 135-146
Author(s):  
Namita Poudel
Keyword(s):  
Social Structure ◽  
Social Field ◽  
Self Identity ◽  
The Social ◽  
Social Fields ◽  
Research Questions

One of the profound questions that troubled many philosophers is– “Who am I?” where do I come from? ‘Why am I, where I am? Or “How I see myself?” and maybe more technically -What is my subjectivity? How my subjectivity is formed and transformed? My attempt, in this paper, is to look at “I”, and see how it got shaped. To understand self, this paper tries to show, how subjectivity got transformed or persisted over five generations with changing social structure and institutions. In other words, I am trying to explore self-identity. I have analyzed changing subjectivity patterns of family, and its connection with globalization. Moreover, the research tries to show the role of the Meta field in search of subjectivity based on the following research questions; how my ancestor’s subjectivity changed with social fields? Which power forced them to change their citizenship? And how my identity is shaped within the metafield? The methodology of my study is qualitative. Faced to face interview is taken with the oldest member of family and relatives. The finding of my research is the subjectivity of Namita Poudel (Me) is shaped by the meta field, my position, and practices in the social field.

Governance in Online Stolen Data Markets

2017 ◽  
Author(s):  
Meltem Odaba¸ ◽  
Thomas J. Holt ◽  
Ronald L. Breiger
Keyword(s):  
Social Structure ◽  
Communication Networks ◽  
State Intervention ◽  
Governance Structure ◽  
Economic Organization ◽  
User Groups ◽  
Underground Economies ◽  
Two Sided Markets

We analyze the governance structure of online stolen data markets. As cybercriminal underground economies, stolen data markets are beyond the reach of state intervention, and yet they need form and regulation in order to function. While the illicit nature of the business brings risks to its participants, the online characteristics of these markets enable the participants to communicate easily, which is a crucial means of generating trust. We first identify stolen data markets in terms of their economic organization as two-sided markets, economic platforms with two distinct user groups that provide each other with network synergies. This characterization enables us to understand the role of the forum administrator as that of an intermediary, market creator, and market regulator. Then we clarify the role of communication networks and social structure in creating trust among buyers and sellers.

scholarly journals Family feud: permanent group splitting in a highly philopatric mammal, the killer whale (Orcinus orca)

2021 ◽  
Vol 75 (3) ◽  
Author(s):  
Eva H. Stredulinsky ◽  
Chris T. Darimont ◽  
Lance Barrett-Lennard ◽  
Graeme M. Ellis ◽  
John K. B. Ford
Keyword(s):  
Killer Whale ◽  
Group Structure ◽  
Group Living ◽  
Orcinus Orca ◽  
Learning Approaches ◽  
Killer Whales ◽  
Internal Factors ◽  
Individual Fitness ◽  
Leadership Experience

Abstract For animals that tend to remain with their natal group rather than individually disperse, group sizes may become too large to benefit individual fitness. In such cases, group splitting (or fission) allows philopatric animals to form more optimal group sizes without sacrificing all familiar social relationships. Although permanent group splitting is observed in many mammals, it occurs relatively infrequently. Here, we use combined generalized modeling and machine learning approaches to provide a comprehensive examination of group splitting in a population of killer whales (Orcinus orca) that occurred over three decades. Fission occurred both along and across maternal lines, where animals dispersed in parallel with their closest maternal kin. Group splitting was more common: (1) in larger natal groups, (2) when the common maternal ancestor was no longer alive, and (3) among groups with greater substructuring. The death of a matriarch did not appear to immediately trigger splitting. Our data suggest intragroup competition for food, leadership experience and kinship are important factors that influence group splitting in this population. Our approach provides a foundation for future studies to examine the dynamics and consequences of matrilineal fission in killer whales and other taxa. Significance statement Group living among mammals often involves long-term social affiliation, strengthened by kinship and cooperative behaviours. As such, changes in group membership may have significant consequences for individuals’ fitness and a population’s genetic structure. Permanent group splitting is a complex and relatively rare phenomenon that has yet to be examined in detail in killer whales. In the context of a growing population, in which offspring of both sexes remain with their mothers for life, we provide the first in-depth examination of group splitting in killer whales, where splitting occurs both along and across maternal lines. We also undertake the first comprehensive assessment of how killer whale intragroup cohesion is influenced by both external and internal factors, including group structure, population and group demography, and resource abundance.

scholarly journals Hand Hygiene Knowledge, Perception, and Practices among Domestic Visitors to the Prophet’s Mosque in Al Madinah City Amid the COVID-19 Pandemic: A Cross-Sectional Study

2021 ◽  
Vol 18 (2) ◽  
pp. 673
Author(s):  
Hashim A. Mahdi ◽  
Hamza M. Assaggaf ◽  
Mohammad Alfelali ◽  
Omar B. Ahmed ◽  
Radi Alsafi ◽  
...  
Keyword(s):  
Hand Hygiene ◽  
Graduate Education ◽  
Formal Education ◽  
Demographic Data ◽  
Knowledge Score ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional Survey ◽  
Cross Sectional

This study aimed to assess hand hygiene knowledge, perception, and practices of visitors to the Prophet’s Mosque in Al Madinah City, Saudi Arabia. Using a self-administered electronic questionnaire, a cross-sectional survey was conducted among domestic residents, who visited the mosque between 31 July and 3 August 2020. Participants’ demographic data, hand hygiene knowledge, perception, and practices were collected. Four hundred participants aged 18–65 (median 36) years completed the survey, of which 215 (53.8%) were female. The visitors’ mean knowledge score about hand hygiene was 6.4 (± standard deviation (SD) 1.35) of total 12. Most participants (392, 98%) were aware of the role of hand hygiene in preventing Coronavirus Disease 2019 (COVID-19); nevertheless, 384 (96%) said hand hygiene lowers body immunity and 316 (79%) thought <60% alcohol is sufficient for hand disinfection. Males had a higher knowledge score than females (6.46 (±1.41) vs. 6.14 (±1.27), p = 0.02) and, visitors who had no formal education scored higher than those with post-graduate education (6.88 (±1.45) vs 5.73 (±1.12), p = 0.01). Washing hands with soap and water was the predominant method practiced after a meal (365, 91.7%), after toilet visit (354, 88.5%), after touching a surface (262, 65.7%), after waste disposal (332, 83.2%), and when hands were visibly dirty (357, 89.5%). Al Madinah visitors had moderate knowledge about hand hygiene, but demonstrated some knowledge gaps and negligence in practice that are crucial to curb the spread of COVID-19.

scholarly journals Seeing Children in Prehistory: A View from Bronze Age Ireland

2021 ◽  
pp. 1-16
Author(s):  
Mark Haughton
Keyword(s):  
Social Structure ◽  
Bronze Age ◽  
The Past ◽  
Written Sources

Despite growing strength in recent decades, an archaeology of childhood has often been overlooked by those studying prehistory. This is concerning because communities are enlivened by their children, and conversations with and about children often provide a critical arena for the discussion of aspects of societies which prehistorians are comfortable addressing, such as social structure, identity and personhood. Through an exploration of childhood as expressed in the Earlier Bronze Age burials from Ireland, this article demonstrates that neither written sources, artistic depictions nor toys are necessary to speak of children in the past. Indeed, an approach which tacks between scales reveals subtle trends in the treatment of children which speak to wider shared concerns and allows a reflection on the role of children in prehistory.

The Eighteenth-Century Social Order in Surat: A Reply and an Excursus on the Riots of 1788 and 1795

1991 ◽  
Vol 25 (2) ◽  
pp. 321-365 ◽  
Author(s):  
Lakshmi Subramanian
Keyword(s):  
Eighteenth Century ◽  
Social Structure ◽  
Social Order ◽  
Recent Article ◽  
Alternative Explanation ◽  
Archival Material ◽  
The Social

The Banias of eighteenth-century Surat, whom Michelguglielmo Torri earlier treated with indifference if not innocence, have invited his wrath since they were brought into focus by the publication of my essay on the Banias and the Surat riot of 1795. In his ‘rejoinder’ to my article, he seeks to wish away their existence altogether (to him there was no specific Bania community, the term merely signifying traders of all communities engaged in the profession of brokerage), and seeks to provide what he regards as an ‘alternative’ explanation of the Muslim–Bania riot of 1795. the Muslim-Bania riot of 1795. It shall be my purpose in this reply to show that his alternative explanation is neither an alternative nor even an explanation, and is based on a basic confusion in his mind about the Banias as well as the principal sources of tension in the social structure of Surat. I shall treat two main subjects in this reply to his misdirected criticisms. First, I shall present some original indigenous material as well as European documentation to further clarify the identity, position and role of the Banias, whom Irfan Habib in a recent article has identified as the most important trading group in the trading world of seventeenth and eighteenth-century India. It is also my purpose to show how the social order of Surat operated under stress by presenting some archival material, the existence of which Torri seems to be completely unaware of, on the Parsi-Muslim riot of 1788.

Development of intentional stranding hunting techniques in killer whale (Orcinus orca) calves at Crozet Archipelago

1995 ◽  
Vol 73 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Christophe Guinet ◽  
Jérome Bouvier
Keyword(s):  
Growth Curve ◽  
Parental Investment ◽  
Killer Whale ◽  
Elephant Seal ◽  
Orcinus Orca ◽  
Killer Whales ◽  
Juvenile Female ◽  
Adult Females ◽  
Social Transfer ◽  
High Degree

This paper describes the trend in the practice of what we interpret to be the "intentional stranding" hunting technique of two juvenile female killer whales (Orcinus orca), A4 and A5, belonging to pod A on the beaches of Possession Island, Crozet Archipelago. Pod A was composed of three adult females, A2, A3, A6, and one adult male, A1. A2 is A4's mother and A3 is A5's mother. The year of birth and thus the probable age of the two juveniles were estimated from their growth curve determined by means of a photogrammetric technique. These observations indicate that at Crozet Archipelago, juvenile killer whales first practiced intentional stranding on their own when they were 4–5 years old. Their first attempt to capture elephant seal pups by means of this technique was observed when they were 5–6 years old. However, 5- to 6-year-old juveniles still needed the assistance of an adult female to return to the water with their prey. This study indicates that learning hunting techniques needs a high degree of skill and requires high parental investment to reduce the associated risk. Furthermore, social transfer, through apprenticeship, is probably one of the mechanisms that enables the high degree of adaptability observed in killer whales.

scholarly journals Geographical and social isolation drive the evolution of Austronesian languages

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243171
Author(s):  
Cecilia Padilla-Iglesias ◽  
Erik Gjesfjeld ◽  
Lucio Vinicius
Keyword(s):  
Social Structure ◽  
Population Size ◽  
Social Isolation ◽  
Linguistic Diversity ◽  
Cultural Group ◽  
Geographical Isolation ◽  
Austronesian Languages ◽  
New Words ◽  
Gain Loss

The origins of linguistic diversity remain controversial. Studies disagree on whether group features such as population size or social structure accelerate or decelerate linguistic differentiation. While some analyses of between-group factors highlight the role of geographical isolation and reduced linguistic exchange in differentiation, others suggest that linguistic divergence is driven primarily by warfare among neighbouring groups and the use of language as marker of group identity. Here we provide the first integrated test of the effects of five historical sociodemographic and geographic variables on three measures of linguistic diversification among 50 Austronesian languages: rates of word gain, loss and overall lexical turnover. We control for their shared evolutionary histories through a time-calibrated phylogenetic sister-pairs approach. Results show that languages spoken in larger communities create new words at a faster pace. Within-group conflict promotes linguistic differentiation by increasing word loss, while warfare hinders linguistic differentiation by decreasing both rates of word gain and loss. Finally, we show that geographical isolation is a strong driver of lexical evolution mainly due to a considerable drift-driven acceleration in rates of word loss. We conclude that the motor of extreme linguistic diversity in Austronesia may have been the dispersal of populations across relatively isolated islands, favouring strong cultural ties amongst societies instead of warfare and cultural group marking.

scholarly journals An Evaluation of Relationship between Risk, Return and Social Structure and their Impact on Individual Investor’s Behaviour at Pakistan Stock Exchange

2019 ◽  
Vol 15 (1) ◽  
pp. 184-192
Author(s):  
Sumair Farooq ◽  
Keyword(s):  
Social Structure ◽  
Stock Exchange ◽  
Research Paper ◽  
Individual Investors ◽  
Probability Method ◽  
Risk And Return ◽  
Secondary Sources ◽  
Risk Return ◽  
Investor Behaviour

This research paper focusing on twofold purposes: where the first part focuses on providing positive evidence on the nature of relationship between risk and return. Moreover, the second part of the paper deals with analyzing the role of risk and return and social structures on the investor’s behaviour in specific consideration with Pakistan Stock Exchange (PSX) (formerly Karachi Stock Exchange; KSE). This research paper has employed a quantitative approach for the purpose of collection of data and analysis of the results in order to fulfil the aim and objectives of the study. The data for risk and return has been collected from secondary sources. The risk and return for 50 companies that are listed on Pakistan Stock Exchange and at least once paid dividend have been calculated for 11 years which is from 2007 to 2017. Moreover, in order to collect the data for social structure and investor  behaviour  the  researcher  has  used  survey  questionnaire  as  the  research  instrument.  The  questionnaire was filled by 558 individual investors who have invested their capital in the stock of companies listed on Pakistan Stock Exchange. The sampling method that was used for the purpose of selecting respondents for getting the questionnaires filled was non-probability method. For all the independent variables the null hypotheses are rejected thus showing significance of relationship. The results from  the  regression  analysis  has  shown  that  among  all  the  predicting  variables  social  structure explains the lowest amount of variation in investor’s behaviour. Thus, overall it can be said that the results of this study are in alignment with the previous researches.

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