Kin discrimination allows plants to modify investment towards pollinator attraction.

Pollinators tend to be preferentially attracted to large floral displays that may comprise more than one plant in a patch. Attracting pollinators thus not only benefits individuals investing in advertising, but also other plants in a patch through a 'magnet' effect. Accordingly, there could be an indirect fitness advantage to greater investment in costly floral displays by plants in kin-structured groups than when in groups of unrelated individuals.

Altruistic Behavior among Twins : Willingness to Fight and Self-Sacrifice for Their Closest Relatives.

According to kin selection theory, indirect reproductive advantages may induce individuals to care for others with whom they share genes by common descent, and the amount of care, including self-sacrifice, will increase with the proportion of genes shared. Twins represent a natural situation in which this hypothesis can be tested. Twin pairs experience the same early environment because they were born and raised at the same time and in the same family but their genetic relatedness differs depending on zygosity.

The devoted actor's will to fight and the spiritual dimension of human conflict.

Frontline investigations with fighters against the Islamic State (ISIL or ISIS), combined with multiple online studies, address willingness to fight and die in intergroup conflict. The general focus is on non-utilitarian aspects of human conflict, which combatants themselves deem 'sacred' or 'spiritual', whether secular or religious. Here we investigate two key components of a theoretical framework we call 'the devoted actor'-sacred values and identity fusion with a group-to better understand people's willingness to make costly sacrifices.

The evolution of extreme cooperation via shared dysphoric experiences.

Willingness to lay down one's life for a group of non-kin, well documented historically and ethnographically, represents an evolutionary puzzle. Building on research in social psychology, we develop a mathematical model showing how conditioning cooperation on previous shared experience can allow individually costly pro-group behavior to evolve. The model generates a series of predictions that we then test empirically in a range of special sample populations (including military veterans, college fraternity/sorority members, football fans, martial arts practitioners, and twins).

What happens when family resources are across international boundaries? An exploratory study on kinship placement in Mexican immigrant families.

Children in Latino immigrant families are significantly less likely to be placed in kinship care than other children are. Using grounded theory, the researchers conducted focus groups and individual interviews with child welfare workers working with Mexican origin families in south Texas to study the extent to which they use international kin placement resources. Key barriers to international kinship placement include lack of accurate information concerning international placements and conflicting agency mandates.