Altruistic actions are generally seen as 'noble'. Yet some 'lowly' organisms are apt to match the most heroic human acts of devotion and self-sacrifice. To use a widely-quoted example, consider Dicrocoelium dendriticum, also known as brainworm. These parasites spend some of their stages in the innards of cows, exit in the feces and, in the form of cercaria, are eaten by ants a few stages later....

We study the evolution of altruism in one- and two-dimensional stepping-stone populations with discrete overlapping generations. We find that increasing survival probability facilitates the evolution of altruism, in agreement with recent results for a patch-structured population. We allow the altruistic behaviour to affect either fecundity or survival probability. In the first case, altruism is...

A very simple reciprocal activity elicited high degrees of altruism in 1- and 2-y-old children, whereas friendly but nonreciprocal activity yielded little subsequent altruism. In a second study, reciprocity with one adult led 1- and 2-y-olds to provide help to a new person. These results question the current dominant claim that social experiences cannot account for early occurring altruistic be...

THE EFFECT OF INBREEDING ON SOCIALITY IS STUDIED THEORETICALLY FOR THE EVOLUTION OF INTERACTIONS BETWEEN SIBLINGS IN CERTAIN MIXED MATING SYSTEMS THAT GIVE RISE TO INBREEDING: sib with random mating and selfing with random mating. Two approaches are taken. First, specific models of altruism are studied for the various mating systems. In the case of the additive model, inbreeding facilitates the...

This paper asks whether individuals consider the value future generations will receive from environmental quality when deciding what level of environmental protection to provide. Using data on life expectancy, I develop two tests for altruism towards future generations. One, a test for strong altruism, asks whether individual motives are purely altruistic when deciding to provide environmental ...

Background The Dark Triad literature examining pro-social behaviours is minimal, with mixed results. Participants and procedure This study investigates the relationships between altruistic based on self-report data from 286 adults. Altruism was assessed using two scales: a general measure as well more recent scale measur-ing compassionate altruism towards family, friends, strangers. Results Mac...

This paper studies the long-run aggregate and welfare effects of eliminating Social Security in a quantitative dynamic general equilibrium life-cycle model where parents and their children are linked by voluntary and accidental bequests. Social security in this model with impure altruism has a smaller effect on capital accumulation than in a pure life-cycle model, a bigger effect than in a mode...

If the bene ciary of an altruist's gift can be expected to use this gift e ciently, then a pure altruist (one who cares about the bene ciary's utility level, but not how utility is obtained) should only give gifts of money. This is often interpreted to mean that any other type of gift is evidence of paternal altruism. However, it is known (Linbeck and Weibull (1988)) that altruism creates an in...

Abstract Why do tax rates vary so much across countries? We study the role of other-regarding preferences and ethnic fragmentation in redistribution. A government is elected by altruistic voters chooses a redistributive income tax. Altruism directed towards social identity groups. Three main factors yield low levels redistribution: (i) strong in-group altruism among rich voters—referred to as c...