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In singular cooperative breeders few females breed successfully, but those that acquire dominant positions can achieve high levels of breeding success, leading to strong selection for traits that enable individuals to acquire and maintain dominance status. However, little is known about the process by which females acquire dominant breeding status or the traits that enable them to do so. Female meerkats, Suricata suricatta, can acquire dominance either by inheritance after the death of the previous dominant, by displacing the incumbent dominant or at the foundation of a new group. Here we investigated the possible fitness benefits associated with these different routes to dominance and the traits that affect an individual's probability of acquiring dominance via these routes. We found that all routes to dominance had similar fitness benefits and that when a dominance vacancy arose, weight was the main determinate of succession, with age still influencing within-group succession and the eldest subordinate female, the beta, often succeeding to dominance. Since the chance that subordinate females will acquire dominance is also positively correlated with the duration of their tenure in the beta position, we tested whether beta females adjusted their growth or cooperative behaviour to avoid eviction and increased their tenure length as the beta. However, there was no indication that betas employed either strategy to increase their tenure. Given that the differing routes to dominance have equivalent fitness pay-offs and are triggered stochastically, selection probably favours flexibility rather than strategies that commit individuals to a specific route.

We studied healthy supine astronauts on Earth with electrocardiogram, non‐invasive arterial pressure, respiratory carbon dioxide concentrations, breathing depth and sympathetic nerve recordings.The null hypotheses were that heart beat interval fluctuations at usual breathing frequencies are baroreflex mediated, that they persist during apnoea, and that autonomic responses to apnoea result from changes of chemoreceptor, baroreceptor or lung stretch receptor inputs.R‐R interval fluctuations at usual breathing frequencies are unlikely to be baroreflex mediated, and disappear during apnoea.The subjects’ responses to apnoea could not be attributed to changes of central chemoreceptor activity (hypocapnia prevailed); altered arterial baroreceptor input (vagal baroreflex gain declined and muscle sympathetic nerve burst areas, frequencies and probabilities increased, even as arterial pressure climbed to new levels); or altered pulmonary stretch receptor activity (major breathing frequency and tidal volume changes did not alter vagal tone or sympathetic activity). Apnoea responses of healthy subjects may result from changes of central respiratory motoneurone activity.

In the triennium 2006-2008, 261 women in the UK died directly or indirectly related to pregnancy. The overall maternal mortality rate was 11.39 per 100,000 maternities. Direct deaths decreased from 6.24 per 100,000 maternities in 2003-2005 to 4.67 per 100,000 maternities in 2006–2008 (p = 0.02). This decline is predominantly due to the reduction in deaths from thromboembolism and, to a lesser extent, haemorrhage. For the first time there has been a reduction in the inequalities gap, with a significant decrease in maternal mortality rates among those living in the most deprived areas and those in the lowest socio-economic group. Despite a decline in the overall UK maternal mortality rate, there has been an increase in deaths related to genital tract sepsis, particularly from community acquired Group A streptococcal disease. The mortality rate related to sepsis increased from 0.85 deaths per 100,000 maternities in 2003-2005 to 1.13 deaths in 2006-2008, and sepsis is now the most common cause of Direct maternal death. Cardiac disease is the most common cause of Indirect death; the Indirect maternal mortality rate has not changed significantly since 2003-2005. This Confidential Enquiry identified substandard care in 70% of Direct deaths and 55% of Indirect deaths. Many of the identified avoidable factors remain the same as those identified in previous Enquiries. Recommendations for improving care have been developed and are highlighted in this report. Implementing the Top ten recommendations should be prioritised in order to ensure the overall UK maternal mortality rate continues to decline.

Functional interpretations of helping behaviour suggest that it has evolved because helpers increase their direct or indirect fitness by helping. However, recent critiques have suggested that helping may be an unselected extension of normal parental behaviour, pointing to evidence that all mature individuals commonly respond to begging young (whether they are parents, relatives or non-relatives) as well as to the lack of evidence that cooperative activities have appreciable costs to helpers. Here we provide an example of one form of cooperative behaviour that is seldom performed by parents and has substantial energetic costs to helpers. In the cooperative mongoose, Suricata suricatta, non-breeding adults commonly babysit young pups at the natal burrow for a day at a time, foregoing feeding for 24 hours. Parents rarely contribute to babysitting, and babysitting has substantial energetic costs to helpers. Members of small groups compensate for the reduced number of participants by babysitting more frequently, and neither the proportion of time that babysitters are present nor the survival of litters vary with group size.