Witnessing reconciliation reduces arousal of bystanders in a baboon group (Papio hamadryas hamadryas)

Reconciliation is the occurrence of friendly behaviour between opponents shortly after an aggressive conflict. In primate groups, reconciliation reduces aggression and postconflict arousal. Aggression within a group can also increase arousal of bystanders (e.g. increase bystanders' rates of self-directed behaviour). Since reconciliation reduces aggression between opponents, we tested whether it also reduces self-directed behaviour in bystanders. Following aggression in a captive group of hamadryas baboons, one observer conducted a focal sample on one of the combatants to document reconciliation and a second observer simultaneously conducted a focal sample on a randomly selected bystander. Matched control observations were then collected on the same individuals in a nonaggressive context to obtain baseline levels of behaviour. The self-directed behaviour of bystanders was elevated after witnessing a fight compared to baseline levels. If combatants reconciled aggression, bystander rates of self-directed behaviour significantly decreased. If combatants did not reconcile aggression, bystander rates of self-directed behaviour remained at elevated levels, significantly higher than after reconciliation. If combatants affiliated with partners other than their original opponent, bystander rates of self-directed behaviour did not decrease. The rate of bystander self-directed behaviour after a combatant affiliated with its opponent was significantly lower than the rate after a combatant affiliated with other animals. Witnessing aggression increased arousal in bystanders, and reconciliation between the combatants was accompanied by reduced bystander arousal. The reduction was specific to contexts in which former opponents interacted. We suggest that bystanders recognized the functional significance of this conflict-resolution mechanism when it occurred in their group. (c) 2013 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Trends in the Association Between Socioeconomic Status and Obesity in U.S. Adults: 2002-2012

Since the 1980s, the prevalence of obesity has more than doubled to over 30 percent of the adult population (Thorpe, 2004). Obesity is a key contributing factor to continually rising national healthcare costs. Addressing its negative implications is essential not only from a cost perspective, but also for the betterment of our nation¿s general health and wellbeing. Obesity is reportedly associated with a 35% increase in inpatient and outpatient spending, as well as a 77% increase in related necessary medications (Sturm, 2002). Obesity, which some have argued should be classified as a disease in itself, has roughly the same association with the development of chronic health conditions as does 20 years of aging (Sturm, 2002). Defined as ambulatory care-sensitive conditions, these obesity-related chronic health diagnoses ¿ like diabetes, cardiovascular disease, and hypertension ¿ are in turn the primary drivers of current healthcare spending, as well as future predicted health expenditures. It is well established that lower socioeconomic status (SES) is associated with higher rates of obesity and the subsequent development of aforementioned obesity-related conditions. Socioeconomic status has traditionally been defined by education, income, and occupation (Adler, 2002); however, this study found empirical evidence for education being the most fundamental of these three SES indicators in determining obesity outcomes. For both men and women, as education levels increased, the likelihood of an individual being obese decreased. However, with less education, there was increased disparity between the obesity rates for men and women. Women consistently saw higher rates of obesity and were more impacted in terms of obesity onset by belonging to a lower SES category than men. In addition, this study assessed whether the impact of one¿s socioeconomic status on obesity-related health outcomes (specifically the negative impact low-SES as measured by education level) has changed over time. Results deriving from annual data from the National Health Interview Survey (NHIS) for all years from 2002 to 2012 indicate that the association between low-socioeconomic status and negative health outcomes has not increased in magnitude over the past decade. Instead, obesity rates have increased across the overall U.S. adult population, most likely due to a number of larger external societal factors resulting in increased caloric intake and decreased energy expenditure across every SES group. In addition, while the association between low-SES and obesity has not worsened, a consequence of the Great Recession has been a larger percentage of the U.S. population in lower-SES, which is still consistently subject to the same worse health outcomes.