Quantitative Matching of Clutch Size in Reciprocating Hermaphroditic Worms.

Reciprocity [1] is one of the most controversial evolutionary explanations of cooperation among non-kin [2, 3]. For some authors, cognitive capacity of non-human organisms is limiting, and more parsimonious mechanisms should apply [3-5]; for others, the debate is mainly semantic [2, 6], and empirical evidence can be found in a wide range of taxa [7]. However, while the ability to alternate cooperative behaviors does not settle the reciprocity controversy, the capacity to adjust cooperative behavior to the value of received help could prove decisive.

Social networks dynamics revealed by temporal analysis: An example in a non-human primate (Macaca sylvanus) in "La Forêt des Singes".

This study applied a temporal social network analysis model to describe three affiliative social networks (allogrooming, sleep in contact, and triadic interaction) in a non-human primate species, Macaca sylvanus. Three main social mechanisms were examined to determine interactional patterns among group members, namely preferential attachment (i.e.

Anarchy Is a Molecular Signature of Worker Sterility in the Honey Bee.

Worker sterility is a defining characteristic of eusociality. The existence of the sterile worker caste remains a fundamental question for evolutionary biology as it requires the existence of genes that reduce personal reproduction. Currently, little is known about the proximate mechanisms underpinning worker sterility.

Effects of natural mating and CO2 narcosis on biogenic amine receptor gene expression in the ovaries and brain of queen honey bees, Apis mellifera.

A queen honey bee mates at ∼6 days of age, storing the sperm in her spermatheca for life. Mating is associated with profound changes in the behaviour and physiology of the queen but the mechanisms underlying these changes are poorly understood. What is known is that the presence of semen in the oviducts and spermatheca is insufficient to initiate laying, and that copulation or CO(2) narcosis is necessary for ovary activation.

Enriched topological learning for cluster detection and visualization.

The exponential growth of data generates terabytes of very large databases. The growing number of data dimensions and data objects presents tremendous challenges for effective data analysis and data exploration methods and tools. Thus, it becomes crucial to have methods able to construct a condensed description of the properties and structure of data, as well as visualization tools capable of representing the data structure from these condensed descriptions.

Boys and girls on the playground: sex differences in social development are not stable across early childhood.

Sex differences in human social behaviors and abilities have long been a question of public and scientific interest. Females are usually assumed to be more socially oriented and skillful than males. However, despite an extensive literature, the very existence of sex differences remains a matter of discussion while some studies found no sex differences whereas others reported differences that were either congruent or not with gender stereotypes.