Re: Trivers' Reciprocal Altruism

From: Tommy (
Date: Sun Nov 16 1997 - 17:51:57 GMT

In the tutorial on the evolution of reciprocal altruism the
altruistic behaviour shown in species, such as cleaning
symbiosis in certain fish and warning calls in birds were
used as non-human examples, which seemed to apply to the

However, a lot was said on the misgivings of the application
of Trivers' model to human altruistic behaviour. After
rereading the paper it doesn't seem so difficult to see that
it's use on humans is all that wrong (just on a different
level). It's easy to study the behaviour in other species,
but we can only assume and make inferences on our own
behaviour as we are no longer in the EEA. Therefore, we base
the assumptions on what we know of ourselves and past, and
hope that it's right.

Trivers concentrates on the underlying emotional dispositions
affecting altruistic behaviour, suggesting that these have
important genetic components. And these emotions develop
after an altruistic system has appeared to regulate it.
Trivers suggests that moralistic aggression counteracts
altruistic tendencies, enables you to withdraw friendship or
even harm individuals who are unreciprocating. And that guilt
has been selected to motivate cheaters to compensate for
misdeeds by behaving altruistically in the future.
This thought has been developed because natural selection in
humans favours a complex psychological system that regulates
altruistic and cheating behaviours, enabling people to
maximise altruistic exchanges and protect against subtle

If a fish cheats by eating it's cleaner it will have to find
a new one and risk contact with cheat 'mimic' cleaner fish.
The same is true of humans- unreciprocating behaviour may
cause the breaking down of a relationship and the search for
other friends. Thus they risk exposure to forms of cheating.
Therefore natural selection favours altruism as long as there
is an efficient regulatory system, and this is probably where
the criticisms lie in the jump from non-human to human

Cheating is very cut and dry in the examples of non-human
species -The big fish cheats by eating the cleaner, the
cleaner fish are invaded by mimics who hope that they don't
get caught.

Where in humans the variables are much greater in our form of
social interaction and therefore our regulatory system must
account for the varying levels altruism and it's effects in
different situations. So the cost-benefit ratio would be more
complex but the result 'could' have been worked out through
unconscious processes which form a conscious emotion which is
behaved upon.

The same idea of unconscious processes was used in an example
from Sperm Wars, I think it went something like this; If a
woman is unfaithful it prompts a conscious feeling of guilt
towards her partner increasing the chances of her having sex
with him. However, the guilt feeling may be a byproduct of
the subconscious desire to start a sperm war (so insemination
is by the strongest swimmers).

The unconscious message in reciprocal altruism may be to
protect against cheats, so when someone is unreciprocating
there is a conscious feeling of aggression which prompts
behaviours such as; -to stop the friendship -make other feel
guilty so they act altruistically later -punish other etc.
Of course this is a pretty basic scenario but it seems
relevant enough to be considered as a possible regulatory
system for human altruism. A more complicated example would
just involve a more complex cost-benefit ratio analysis (to
arrive at an outcome that is situation specific).
Either way this type of talk of unconscious processes/emotion
based behaviour is all speculation of what the cause might be.

Part of the argument (in the tutorial) against the use of
Trivers' model on human alt. beh. was the scenario of the man
who formed a 'human bridge' on a sinking ship for people
other than his kin.

It doesn't seem that this question need worry the Trivers
paper, it seems better to put this to the selfish gene. In
terms of the selfish gene he should have helped his kin and
then got out himself, however we go against our genetically
predetermined behaviour all the time ( Dawkins noted that
cultural practices can override biological predispostions and
tried to explain it in terms of memes).

The biggest must be the decision not to have children. We are
genetically designed to reproduce and live in a social context that to
some extent promotes it. It can't be a biological trait and if it were
it would have been selected out by now. It couldn't have existed in the
EEA as there is no benefit to the evolution of any species that behaved
like that. So in choosing not to reproduce (in gene terminology) we
may as well be dead men/women walking, we might as well be the person
dangling above a drop forming a human bridge on a sinking ship helping
strangers.*Don't take that literally - I know about helping our genes
succeed through helping kin. What I think I'm babbling on about is
that to some extent the integration of human emotion and the ability to
consciously reflect upon them allows us to break away from the
biological based origins of behaviour.

For example; It may have been Mr. human bridge's desire to
help his genes (kin selection) that got him down there in the
first place and the underlying emotional dispositions that
kept him there. e.g.-To gain gratitude -To avoid the guilt of
not helping others especially if it meant causing their

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