It stands to reason therefore that parents will protect their children selflessly because, in overly simplified terms, their offspring carries half of their genes. Brothers and sisters carry half of the same genes and this explains why they might behave altruistically towards each other. However, parental behaviour is far more altruistic and this is explained by this theory in terms of life expectancy; the greater the life expectancy, the greater the chance of the genes being replicated.
However, it is difficult to understand why a person may behave altruistically towards grandparents and other elderly members of the family when often this doesn’t appear to benefit the actor’s genetic success directly or indirectly; the fact that this seems to decrease the fitness of the actor means that this provides a limitation regarding the kin selection concept within the selfish gene theory when trying to explain cooperative and social behaviours.
Another challenge to the kin selection theory is the questionable ability of the actor to be able to distinguish someone with whom they are related from someone with whom they are not. Dawkins (1976) explains a person’s capacity to discriminate outside of direct kin through a phenomenon known as the Green beard effect (Hamilton, 1964, 1975; Dawkins, 1976; Jansen & Van Baalen, 2006). According to Dawkins (1976) genes help to program those they embody to behave in ways that ensure their survival and replication; this genetically influenced behaviour is known as phenotypic (Johannsen, 1911).
Dawkins posits that the closer organisms are related the more genes they will share and where the phenotypic propensity is to behave altruistically, these organisms will behave in this way towards each other to protect the interest of those genes. This apparent altruistic behaviour is therefore selfish at the level of the genes even if it appears to be altruistic at the level of the organism and so kin discrimination is an ultimately selfish mechanism to ensure copies of these shared genes are populated in greater numbers.
Another way of ensuring that the actor bestows these generosities on those who share their genes is the assumption that the recipients live near to the actor which is known as limited dispersal. This is the theory that a person is more likely to help another person from a neighbouring group due to an increased likelihood that they might share genes based upon the proximity and the likelihood that the degree of relatedness will therefore be above average for the population (Hamilton, 1964).
More recent research demonstrates that the potential benefits from cooperation through higher probabilities of relatedness are cancelled out by the competition led to by this relatedness (Kummerli et al, 2008) and that cooperation is more likely to be favoured when those who share a higher degree of relatedness disperse in groups, this is known as budding dispersal (Kummerli et al, 2008).
This may mean that dispersal does have a benefit on the selection of cooperative traits at the genetic level but only if the organisms disperse in groups; SGT would likely suggest that genes therefore influence people to disperse in groups to reap these fitness benefits. Whilst this discrimination towards helping those who share the same genes makes sense, based on this logic is it incapable of explaining why cooperative and social behaviours occur between those who do not share genes.
Why would a person behave in a way that seemingly has no fitness benefits for themselves or those of possible genetic significance and furthermore what if this behaviour appears to bestow cost on the actor. An explanation for why people help others when they are not related to the recipient is ‘reciprocal altruism’ (Trivers 1971; Kreb & Davies, 1993; Griffin & West, 2002; Frank, 2003; West et al, 2006; Lehmann & Keller, 2006) this is where people help each other on the assumed proviso that when they need help another person will return this type of behaviour (Frank, 2003; West et al, 2006).
SGT would stress that through this interaction there is a direct long term fitness benefit for the actor. However, without concrete reciprocal altruism where by favours are paid directly in proportion to the original favour in exactly equal measures, there is no certainty that the favour will ever be returned and therefore this concept may be found wanting; this will be demonstrated later when the public goods game is explained outlining the ways in which this type of behaviour decreases over time.
Perhaps these social and cooperative behaviours are better understood when they are examined in their context; the impact of a behaviour on individual fitness relative to the group to which the individual belongs. There is evidence that some people have a strong predisposition to act in a way that rewards cooperative behaviour and punishes those who violate this norm and they do so in a way which incurs significant cost to themselves with seemingly no expectation of reciprocation by any other party at any date in the future, altruistically.
This behaviour is indiscriminate and thus attempts to explain cooperative and social behaviours directed outside of those related to the actor; this propensity is known as strong reciprocity and there is experimental evidence to support its existence. Drawing again on game theory, the ‘public goods’ game is an experimental means to measure cooperation between people who have never met in a situation where there are repeated interactions with outcomes that either benefit the group as a whole or the individual.
Each individual starts the game with the same number of points; these points are swapped at the end of the game for real money. The players are told that there will be a set number of rounds, 10 for example and that in each round they can contribute a certain percentage of their points in to a common account and the rest in to their own personal account. At the end of each round the experimenters would tell the players the total amount in the common account and would pay a percentage of this in to the personal accounts of all the players.
