Forming strong, equitable, and enduring social bonds with a few individuals in a group carries adaptive benefits in terms of increased longevity, offspring survival and paternity success in birds and mammals, including humans. These recent insights generated a new interest in the factors creating variation in the strength of social relationships. Whether and how animals discriminate paternal ki...

Comparative studies of social insects and birds show that the evolution of cooperative and eusocial breeding systems has been confined to species where females mate completely or almost exclusively with a single male, indicating that high levels of average kinship between group members are necessary for the evolution of reproductive altruism. In this paper, we show that in mammals, the evolutio...

In 2012, a skeleton was excavated at the presumed site of the Grey Friars friary in Leicester, the last-known resting place of King Richard III. Archaeological, osteological and radiocarbon dating data were consistent with these being his remains. Here we report DNA analyses of both the skeletal remains and living relatives of Richard III. We find a perfect mitochondrial DNA match between the s...

Rhesus macaque females regularly copulate with a number of partners, and produce a single offspring per reproductive cycle in over 99% of cases. We used genotyping of 10 STR markers to determine paternity in the Cayo Santiago population of rhesus macaques. About 1,500 monkeys have been analyzed to date, with their marker genotypes entered into a computerized database. These data enable us to re...

OBJECTIVE To determine the level of Anxiety, Depression and Stress among the Husbands of Obstetric Cases. SUBJECTS AND METHODS This hospital-based prospective study was conducted at Karachi, during the year 1998. A semi-structured proforma along with Hospital Anxiety Depression Scale (HAD) and Life Events Scale were administered to the consenting spouses of obstetric cases. RESULTS Only 23%...

People hardly ever realize that their belief in their high rate of success in detecting family resemblances is affected by their knowledge of the actual genetic link between individuals. In the three studies reported here, 100 men and 100 women were requested to estimate the facial resemblance of photographically portrayed child-adult pairs, while being given either truthful or deceitful inform...

Paternity analyses using molecular markers have become standard in studies of mating systems, parentage, and kinship. In systems where individuals exhibit alternative mating strategies, molecular analyses have been productively used to estimate the reproductive success of each behavioral type and hence the fitness consequences to each individual. Here we review the fitness results in a system o...

The female perspective on reproductive strategies remains one of the most active areas of debate in biology. Even though a single mating is often sufficient to satisfy the fertilization needs of most females and the act of further mating incurs costs, multiple paternity within broods or clutches is a common observation in nature. Direct or indirect advantage to females is the most popular expla...

Experimental studies of mate choice have normally focused on non-mammal animal species, in which female mating preferences are based on clearly defined male traits. Because mammals are invariably larger and behaviourally more complex, they are less suited to this type of experimentation. Nevertheless, numerous studies on nonhuman mammals have shown that females appear to actively choose their m...

It has been hypothesized that parents increase their fitness by biasing the sex ratio of extra-pair offspring (EPO) towards males. Here, we report a male bias among EPO in a wild population of blue tits (Cyanistes caeruleus). This resulted from a decline in both the proportion of males and EPO over the laying order of eggs in the clutch. However, previous studies suggest that, unlike the declin...