The physical demands of rapid and economical running differ from the demands of fighting in ways that may prevent the simultaneous evolution of optimal performance in these two behaviors. Here, we test an hypothesis of functional trade-off in limb bones by measuring mechanical properties of limb bones in two breeds of domestic dog (Canis lupus familiaris L.) that have undergone intense artifici...

OBJECTIVE The prevalence, persistence, and desistance of boys' physical fighting was examined over a 7-year period. The importance of persistent physical fighting compared with other risk factors in the prediction of later mental health problems was explored. METHOD One hundred seventy-seven boys, aged 7 to 12 years, who had been referred to clinics for mental health problems were followed up...

As for multi-uninhabited aerial vehicle cooperative fire fighting problem, a multiuninhabited aerial vehicle cooperative control method was proposed based on consensus algorithm. multi-uninhabited aerial vehicle cooperative control problem was divided into two steps: 1) a multi-uninhabited aerial vehicle arrival simultaneous control strategy under influence of wind field based on consensus algo...

Group living animals may eavesdrop on signalling interactions between conspecifics in order to collect adaptively relevant information obtained from others, without incurring in the costs of first-hand information acquisition. This ability (aka social eavesdropping) is expected to impact Darwinian fitness, and hence predicts the evolution of cognitive processes that enable social animals to use...

OBJECTIVE The objective of this study was to investigate the effect of 20-day litter weight on behavior and heart rate variability (HRV) of piglets under stress. METHODS Forty four original litters were categorized as high litter weight (HW) litters (n = 22) and low litter weight (LW) litters (n = 22) by 20-day litter weight. From each original HW litter, three males and three females were ra...

OBJECTIVES Physical fighting is a behaviour of concern that puts adolescents at increased risk for injury. The study objectives were to: 1) describe current patterns of physical fighting and fighting-related injury among Canadian adolescents, and 2) investigate potential trends in fighting and fighting-related injuries during the period 1993-2010. METHODS Canadian data from cycles 2-6 (1993-2...

The concept of parasite-mediated sexual selection assumes that females may improve offspring fitness by selecting mates on the basis of sexual ornaments that honestly reveal the health state of a partner. Expression of such signals may be particularly sensitive to oxidative damage caused by excess production of oxidative metabolites and free radicals. To control and neutralise free radicals, an...

Segregation and medicated early weaning are technologies used to optimize the productivity and health of pigs, but these practices may also cause aberrant behaviors indicative of stress. Thus, differences in early- (=10 d of age) and late- (=30 d of age) weaned pigs were investigated. At weaning, pigs were housed in groups of four in 16 pens (eight pens per treatment) in the same facility, and,...

Natural killer cells hunt rogue cancer in the bloodstream aided by increased fluid shear stress.