Sperm whale social units: variation and change

1998 ◽  
Vol 76 (8) ◽  
pp. 1431-1440 ◽  
Author(s):  
Jenny Christal ◽  
Hal Whitehead ◽  
Erland Lettevall
Keyword(s):  
Cost Benefit ◽  
Sperm Whale ◽  
Physeter Macrocephalus ◽  
Unit Size ◽  
Social Unit ◽  
Demographic Processes ◽  
Size Variability ◽  
The Cost ◽  
Social Units

Sperm whale (Physeter macrocephalus) photoidentification data spanning 12 years of study around the Galápagos Islands were examined to investigate the size, variability, and stability of social units. Adult females and immature whales of both sexes have two types of associates: "constant companions," which are members of an individual's "stable" social unit, and "casual acquaintances," which are temporarily associating members of different units. We analysed long-term association patterns and calculated that individuals have a mean of 11.3 constant companions. Estimated social unit size ranged from 3 to 24 individuals. Evidence of splitting and merging of units and of transfer of individuals between units is presented. The estimated overall frequency of these unit-membership changes is 6.3% per individual per year. These forms of unit dynamics are rare in species with male dispersal and matrilineally related social groups, and cannot be easily explained in this species. There is considerable variation in unit size (perhaps caused by demographic processes), suggesting that the benefits of remaining in a social unit usually outweigh selection for some optimal unit size. However, the occurrence of merging and transfers suggests that the ecological or social cost/benefit of leaving one's matrilineal unit may sometimes outweigh the cost/benefit of staying.

scholarly journals Kinship influences sperm whale social organization within, but generally not among, social units

2018 ◽  
Vol 5 (8) ◽  
pp. 180914 ◽  
Author(s):  
Christine M. Konrad ◽  
Shane Gero ◽  
Timothy Frasier ◽  
Hal Whitehead
Keyword(s):  
Sperm Whale ◽  
Sperm Whales ◽  
Degree Relative ◽  
Social Unit ◽  
Control Region Sequences ◽  
Related Pair ◽  
Multi Level ◽  
Association Data ◽  
Social Units

Sperm whales have a multi-level social structure based upon long-term, cooperative social units. What role kinship plays in structuring this society is poorly understood. We combined extensive association data (518 days, during 2005–2016) and genetic data (18 microsatellites and 346 bp mitochondrial DNA (mtDNA) control region sequences) for 65 individuals from 12 social units from the Eastern Caribbean to examine patterns of kinship and social behaviour. Social units were clearly matrilineally based, evidenced by greater relatedness within social units (mean r = 0.14) than between them (mean r = 0.00) and uniform mtDNA haplotypes within social units. Additionally, most individuals (82.5%) had a first-degree relative in their social unit, while we found no first-degree relatives between social units. Generally and within social units, individuals associated more with their closer relatives (matrix correlations: 0.18–0.25). However, excepting a highly related pair of social units that merged over the study period, associations between social units were not correlated with kinship ( p > 0.1). These results are the first to robustly demonstrate kinship's contribution to social unit composition and association preferences, though they also reveal variability in association preferences that is unexplained by kinship. Comparisons with other matrilineal species highlight the range of possible matrilineal societies and how they can vary between and even within species.

scholarly journals Can newborn screening be cost benefit procedure if preventing serious complications of cystic fibrosis?

2021 ◽  
pp. 020-023
Author(s):  
Šubat-Dežulović Mirna ◽  
Pelčić Gordana ◽  
Valković Ana ◽  
Flajšman-Raspor Sanja ◽  
Pelčić Goran ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Newborn Screening ◽  
Metabolic Alkalosis ◽  
Cost Benefit ◽  
Inherited Disease ◽  
Eu Countries ◽  
Life Threatening ◽  
Long Term Prognosis ◽  
The Cost

Cystic Fibrosis (CF) is a common inherited disease with reported mean prevalence of 0.737/10,000 in 27 EU countries (Farrell J Cyst Fibros. 2008). Still, many EU countries have not implemented CF in the Newborn Screening (NBS) programme, including our country. We report the case of a 7-month-old boy whose presenting signs of CF were life-threatening neurological symptoms caused by severe metabolic alkalosis and hypoelectrolytemia. By presenting this case, we argue hoping to persuade the authorities in any country that the available newborn screening for CF is the cost benefit procedure in preventing life treating consequences with the obvious impact on the long-term prognosis of this chronic disease.

scholarly journals Reliability Worth Assessment in Composite Power System Planning and Operation

2014 ◽  
Vol 8 (5) ◽  
pp. 45
Author(s):  
Ali Khraiwish Dalabeeh ◽  
Eng.Hani Hasan Saleh Al-Hajbi
Keyword(s):  
Power System ◽  
Unit Commitment ◽  
Economic Effect ◽  
Cost Benefit ◽  
Electric Power System ◽  
Reliability Indices ◽  
Operational Solution ◽  
The Cost ◽  
Operational Constraints

This study presents a comprehensive procedure for evaluating the reliability indices incorporating reduction in interruption cost, and to relate reliability investments with customer’s benefits. An analytical algorithm is used to obtain the final optimal operational solution by determining unit commitment for each generating unit to reach the maximum profit (minimizing cost) subjected to operational constraints. The paper describes a method based on the complementing short-term planning with long-term planning take into account the cost benefit approach. The proposed method has been demonstrated on the RBTS to show the feasibility and the economic effect of the proposed method, and was applied to the Jordanian Electric Power System (JEPS) to show its application capability.

scholarly journals Cost-Effectiveness of a Problem-Solving Intervention Aimed to Prevent Sickness Absence among Employees with Common Mental Disorders or Occupational Stress

2020 ◽  
Vol 17 (14) ◽  
pp. 5234
Author(s):  
Marijke Keus Van De Poll ◽  
Gunnar Bergström ◽  
Irene Jensen ◽  
Lotta Nybergh ◽  
Lydia Kwak ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Problem Solving ◽  
Mental Disorders ◽  
Sickness Absence ◽  
Common Mental Disorders ◽  
Cost Benefit ◽  
Cost Effective ◽  
Production Loss ◽  
The Cost

The cost-benefit and cost-effectiveness of a work-directed intervention implemented by the occupational health service (OHS) for employees with common mental disorders (CMD) or stress related problems at work were investigated. The economic evaluation was conducted in a two-armed clustered RCT. Employees received either a problem-solving based intervention (PSI; n = 41) or care as usual (CAU; n = 59). Both were work-directed interventions. Data regarding sickness absence and production loss at work was gathered during a one-year follow-up. Bootstrap techniques were used to conduct a Cost-Benefit Analysis (CBA) and a Cost-Effectiveness Analysis (CEA) from both an employer and societal perspective. Intervention costs were lower for PSI than CAU. Costs for long-term sickness absence were higher for CAU, whereas costs for short-term sickness absence and production loss at work were higher for PSI. Mainly due to these costs, PSI was not cost-effective from the employer’s perspective. However, PSI was cost-beneficial from a societal perspective. CEA showed that a one-day reduction of long-term sickness absence costed on average €101 for PSI, a cost that primarily was borne by the employer. PSI reduced the socio-economic burden compared to CAU and could be recommended to policy makers. However, reduced long-term sickness absence, i.e., increased work attendance, was accompanied by employees perceiving higher levels of production loss at work and thus increased the cost for employers. This partly explains why an effective intervention was not cost-effective from the employer’s perspective. Hence, additional adjustments and/or support at the workplace might be needed for reducing the loss of production at work.

scholarly journals Socially segregated, sympatric sperm whale clans in the Atlantic Ocean

2016 ◽  
Vol 3 (6) ◽  
pp. 160061 ◽  
Author(s):  
Shane Gero ◽  
Anne Bøttcher ◽  
Hal Whitehead ◽  
Peter Teglberg Madsen
Keyword(s):  
Social Interactions ◽  
Sperm Whale ◽  
Mantel Test ◽  
Good Evidence ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Sympatric Populations ◽  
The Pacific ◽  
Matrix Correlation ◽  
Social Units

Sperm whales ( Physeter macrocephalus ) are unusual in that there is good evidence for sympatric populations with distinct culturally determined behaviour, including potential acoustic markers of the population division. In the Pacific, socially segregated, vocal clans with distinct dialects coexist; by contrast, geographical variation in vocal repertoire in the Atlantic has been attributed to drift. We examine networks of acoustic repertoire similarity and social interactions for 11 social units in the Eastern Caribbean. We find the presence of two socially segregated, sympatric vocal clans whose dialects differ significantly both in terms of categorical coda types produced by each clan (Mantel test between clans: matrix correlation = 0.256; p  ≤ 0.001) and when using classification-free similarity which ignores defined types (Mantel test between clans: matrix correlation = 0.180; p  ≤ 0.001). The more common of the two clans makes a characteristic 1 + 1 + 3 coda, while the other less often sighted clan makes predominantly regular codas. Units were only observed associating with other units within their vocal clan. This study demonstrates that sympatric vocal clans do exist in the Atlantic, that they define a higher order level of social organization as they do in the Pacific, and suggests that cultural identity at the clan level is probably important in this species worldwide.

scholarly journals Tail regeneration after autotomy revives survival: a case from a long-term monitored lizard population under avian predation

2017 ◽  
Vol 284 (1847) ◽  
pp. 20162538 ◽  
Author(s):  
Jhan-Wei Lin ◽  
Ying-Rong Chen ◽  
Ying-Han Wang ◽  
Kuen-Chih Hung ◽  
Si-Min Lin
Keyword(s):  
Cost Benefit ◽  
Predation Pressure ◽  
Natural Conditions ◽  
Tail Regeneration ◽  
Tail Loss ◽  
Avian Predators ◽  
Predatory Birds ◽  
The Cost ◽  
Caudal Autotomy

Caudal autotomy in lizards has intrigued scientists for more than 100 years. Because of the relative lack of literature under natural conditions, the complicated association among field autotomy rate, real predation pressure, the long-term cost of tail loss, and the benefit of regeneration remains equivocal. In this study, we conducted a 7-year capture–mark–recapture (CMR) programme with a wild population of a sexually dichromatic lizard, Takydromus viridipunctatus . We used autotomy indexes and a contemporary bird census mega-dataset of four predatory birds as predictors to examine the association between tail loss and predation pressure. We further estimated the survival cost of tail loss and alleviation by regeneration under natural conditions through CMR modelling. We found that large and small avian predators affect lizard survival through the following two routes: the larger-sized cattle egret causes direct mortality while the smaller shrikes and kestrels are the major causes of autotomy. Following autotomy, the survival rate of tailless individuals over the next month was significantly lower than that of tailed individuals, especially males during the breeding season, which showed a decline of greater than 30%. This sex-related difference further demonstrated the importance of reproductive costs for males in this sexually dichromatic species. However, the risk of mortality returned to baseline after the tails were fully grown. This study indicates the benefit of tail regeneration under natural conditions, which increases our understanding of the cost–benefit dynamics of caudal autotomy and further explains the maintenance of this trait as an evolutionarily beneficial adaption to long-term predator–prey interactions.

scholarly journals Calves as social hubs: dynamics of the social network within sperm whale units

2013 ◽  
Vol 280 (1763) ◽  
pp. 20131113 ◽  
Author(s):  
Shane Gero ◽  
Jonathan Gordon ◽  
Hal Whitehead
Keyword(s):  
Social Relationships ◽  
Social Role ◽  
Group Formation ◽  
Time Lag ◽  
Group Living ◽  
Sperm Whale ◽  
Physeter Macrocephalus ◽  
Sperm Whales ◽  
Social Unit ◽  
The Social

It is hypothesized that the primary function of permanent social relationships among female sperm whales ( Physeter macrocephalus ) is to provide allomothers for calves at the surface while mothers make foraging dives. In order to investigate how reciprocity of allocare within units of sperm whales facilitates group living, we constructed weighted social networks based on yearly matrices of associations (2005–2010) and correlated them across years, through changes in age and social role, to study changes in social relationships within seven sperm whale units. Pairs of association matrices from sequential years showed a greater positive correlation than expected by chance, but as the time lag increased, the correlation coefficients decreased. Over all units considered, calves had high values for all measured network statistics, while mothers had intermediate values for most of the measures, but high values for connectedness and affinity. Mothers showed sharp drops in strength and connectedness in the first year of their new calves' lives. These broad patterns appear to be consistent across units. Calves appeared to be significant nodes in the network of the social unit, and thus provide quantitative support for the theory in which communal care acts as the evolutionary force behind group formation in this species.

scholarly journals Integrated drought risk assessment to support adaptive policy making in the Netherlands

2022 ◽  
Author(s):  
Marjolein Mens ◽  
Gigi van Rhee ◽  
Femke Schasfoort ◽  
Neeltje Kielen
Keyword(s):  
The Netherlands ◽  
Policy Making ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Economic Consequences ◽  
Drought Risk ◽  
Adaptive Policy ◽  
The Cost ◽  
Support Decision Making

Abstract. Adaptive policy-making to prepare for current and future drought risks requires an integrated assessment of policy actions and combinations of those under changing conditions. This entails quantification of drought risks, integrating drought probability and socio-economic consequences for all relevant sectors that are potentially impacted by drought. The investment costs of proposed policy actions and strategies (various actions combined) can then be compared with the expected risk reduction to determine the cost-effectiveness. This paper presents a method to quantify drought risk in the Netherlands under changing future conditions and in response to policy actions. It illustrates how to use this information as part of a societal cost-benefit analysis and in building an adaptive long-term strategy. The method has been successfully applied to support decision making on the Netherlands’ national drought risk management strategy as part of the National Delta Program for climate change adaptation.

scholarly journals Cost–benefit analysis of a staff recreation centre project: build or lease? – A Case Study

2013 ◽  
Vol 4 (1) ◽  
pp. 41
Author(s):  
Monica Singhania
Keyword(s):  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
New Delhi ◽  
Employee Morale ◽  
Benefit Analysis ◽  
The Cost ◽  
Community Centre

This case study aims at comprehensively assessing a decision by XYZ Ltd (name withheld due to confidentiality), New Delhi, on whether to build or to lease a recreation centre for its rank-and-file employees. Based on a cost–benefit analysis, we concluded that the centre should be built since the company would recover its investment within 11 years. Apart from the financial considerations, the recreation centre could be considered a long-term investment in employee morale, as it would lead to a better quality of life for the staff and their families, and is likely to enhance their sense of belonging and improve productivity. To date, what little space there is available for hosting family functions is reserved for the use of the officers, and only officers and their families are invited to most company functions. Thus, the other employees feel neglected by the management. Hiring a community centre external to the organisation for a function would involve spending a lot of money as the company is located in a prime real estate area where the cost of land and rentals is huge, and sometimes even availability is an issue. Most of the staff cannot afford such places and are generally under a lot of stress whenever they have a family function. This, in turn, tends to affect their productivity. 

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