To all in PY311,
Apologies for the delay in my e-mail but I honestly did not have a clue
what to post. Having had no particular questions or comments come to mind
after our first seminar and feeling that my own particular view had not yet
taken shape enough to find a written form, I was actually hoping to be able
to comment on or discuss any points already raised. Since I have
had some problems with my college e-mail, I have not yet received
any. Therefore, I have decided to post my brief guide to 'The
Selfish Gene' as I felt it would perhaps be more useful than a side
of mindless ramblings written out of obligation. I hope this will
suffice and that you can wait for my views and insights on the
course material to be properly formulated before they are shared or
made public.
Thanks for your understanding,
Klair.
A BRIEF GUIDE TO RICHARD DAWKINS AND THE SELFISH GENE
KEY WORDS AND IDEAS:
The inevitable, blind process of automatic selection between rival
molecules (genes) by reason of their longevity, fecundity and copying
fidelity.
Replicator - "anything in the universe of which copies are made" p.264
Survival Machine - the co-operative venture of many genes into a vehicle
through which the genes can be copied and share an outlet into the future.
Gene pool - the genes of the population in general.
Evolution - Changes in the genetic composition of a population during
successive generations. (The gradual development of more complex organisms
from simpler ones).
A TYPICAL 'DAWKIN-LIKE' SPECULATIVE ACCOUNT OF HOW WE CAME TO BE:
Raw materials such as water, carbon dioxide, methane and ammonia were
subjected to a source of energy such as ultraviolet light. This gave rise
to the 'primeval soup' containing amino acids and perhaps the building
blocks of DNA (purines and pyramidines). Under the influence of further
energy (UV light) these molecules combined into larger molecules and
finally by accident and random jostling of particles a remarkable molecule
that could make copies of itself was formed (a replicator). Inevitably
mistakes occurred as more and more copies of replicators were made (an
essential prerequisite for evolution) some of which gave rise to
improvements and therefore propagated themselves more efficiently.
Eventually mutually compatible replicators began to be formalised in the
creation of discrete vehicles and later many celled bodies. A capacity for
learning and thinking evolved as survival machines that could simulate the
future were one jump ahead of survival machines faced with overt trial and
error. Consciousness probably arose when the brain's simulation of the
world became so complete that it had to involve a model of itself.
A FEW PROVOCATIVE WORDS FROM THE TEXT:
"We no longer have to resort to superstition when faced with the deep
problems: Is there a meaning to life? What are we for? What is man?" p.1
The preservation of the ancient replicators "is the ultimate rationale for
our existence" p.20
"People who think robots are by definition more deterministic than human
beings are muddled (unless they are religious, in which case they might
completely hold that humans have some divine gift of free will denied to
mere machines)" p.32
"It is perfectly possible to hold that genes exert a statistical influence
on human behaviour whilst at the same time believing that this influence
can be modified, overridden or reversed by other influences" p.331
QUICK SUMMARY BY CHAPTER:
1. Why are people? - Introduction to Darwin's Theory of Evolution and the
unit of heredity - the gene.
" A predominant quality to be expected in a successful gene is ruthless
selfishness" p.2
"It is a fallacy - incidentally a very common one- to suppose that
genetically inherited traits are by definition fixed and unmodifiable" p.3
"Darwin's 'survival of the fittest' is really a special case of a more
general law of survival of the stable" p.12
2. The replicators - A speculative account of the origin of life.
"If a group of atoms in the presence of energy falls into a stable pattern
it will tend to stay that way. The earliest form of natural selection was
simply a selection of stable forms and a rejection of unstable ones." P.13
"Evolution is something that happens, willy nilly, in spite of all the
efforts of the replicators (and nowadays of the genes) to prevent it
happening" p.18
3. Immortal coils - Introduction to DNA (2 long chains of nucleotides
twisted in a double helix) which replicates and indirectly supervises the
manufacture of protein.
"DNA can be regarded as a set of instructions for how to make a body
written in the A, T, C, G alphabet of the nucleotides" p.22
The intricate inter-dependence of genes. Alleles, mitosis and
meiosis. Genes as the fundamental
units of natural selection. Cistons, point mutation, inversion,
linkage and mimicry.
"A gene is defined as any portion of chromosomal material that potentially
lasts for enough generations to serve as a unit of natural selection" p.28
"The whole set of genes in a body constitutes a kind of genetic climate or
background, modifying and influencing the effects of any particular gene"
p.36-
"if sexual as opposed to non-sexual reproduction benefits a gene for sexual
reproduction, that is a sufficient explanation for the existence of sexual
reproduction" p.44
"It is good to get into the habit, whenever we are trying to explain the
evolution of some characteristic of asking ourselves simply: 'what effect
will this characteristic have on frequencies of genes in the gene pool?'"
p.45
4. The gene machine - Behaviour, negative feedback, simulation and
learning.
"The genes are master programmers, and they are programming for their
lives. They are judged according to the success of their programs in
coping with the hazards that life throws at their survival machines, and
the judge is the ruthless judge of the court of survival" p.62
"One way for genes to solve the problem of making predictions in rather
unpredictable environments is to build in a capacity for learning"p.57
"Survival machines that can simulate the future are one jump ahead of
survival machines who can only learn on the basis of overt trial and error"
p.59
5. Aggression: stability and the selfish machine - Evolutionary Stable
Strategies (ESS) and fighting. Stable polymorphism.
"An ESS is defined as a strategy which, if most members of a population
adopt it cannot be bettered by an alternative strategy"p.69
"An ESS is stable, not because it is particularly good for the individuals
participating in it, but simply because it is immune from treachery from
within" p.72
6. Genesmanship - Altruism and generation distance / relatedness.
"In order for altruistic behaviour to evolve, the net risk to the altruist
must be less than the net benefit to the recipient multiplied by the
relatedness." P.96
"all examples of child protection and parental care and all associated
bodily organs, milk secreting glands, kangaroo pouches and so on, are
examples of the working in nature of the kin selection principle" p.107
7. Family Planning - Birth rates and Epideictic behaviour. Territoriality
and dominance hierarchies as mechanisms of population regulation.
"Groups whose individual members restrain their own birth-rates are less
likely to go extinct than rival groups whose individual members reproduce
so fast that they endanger the food supply" p.113
"Individual parents practise family planning, but in the sense that they
optimise their birth-rates rather than restrict them for public good" p.122
8. Battle of the generations - Parental Investment (PI), the menopause, the
runt phenomenon, parental / child asymmetry.
Total quantity of Parental Investment (PI) is the sum of all the food
gathered or manufactured in a lifetime of work, all risks prepared to take,
all energy time and effort prepared to put into the welfare of the
children. P.124
"Genes for becoming reproductively infertile in middle age became more
numerous, since they were carried in the bodies of grandchildren whose
survival was assisted by grandmotherly altruism" p.127
"When a gene is sitting in a juvenile body its practical opportunities will
be different from when it is sitting in a parental body" p.137
"We must teach our children altruism, for we cannot expect it to be part of
their biological nature" p.139
9. Battle of the sexes - Gametes, male and female strategies, choosing a
mate.
"The female sex is exploited, and the fundamental evolutionary basis for
the exploitation is the fact that eggs are larger than sperms...Since she
starts by investing more than the male in the form of her large food-rich
egg, a mother is already at the moment of conception 'committed' to each
child more deeply than the father is"
"One of the most desirable qualities a male can have is quite simply sexual
attractiveness itself" p.158
"Because of a fundamental difference between the size and numbers of sperms
and eggs, males are in general likely to be biased towards promiscuity and
lack of paternal care. Females have two available counter-ploys the he-man
and domestic-bliss strategies" p.161
"There are therefore two conflicting selection pressures: predators tending
to remove bright-colour genes from the gene pool, and sexual partners
tending to remove genes for drabness" p.162
10. You scratch my back, I'll ride on yours - mutual symbiosis, alarm
calls, social insects, delayed reciprocal altruism.
"We are gigantic colonies of symbiotic genes" p.182
11. Memes: the new replicators - cultural transmission, conscious
foresight.
" Memes should be regarded as living structures, not just metaphorically
but technically. When you plant a fertile meme in my mind you literally
parasitize my brain turning it into a vehicle for the meme's propagation in
just the way that a virus may parasitize the genetic mechanism of a host
cell." P.192
"Selection favours memes that exploit their cultural environment to their
own advantage. This cultural environment consists of other memes which are
also being selected" p. 199
"We should not seek immortality in reproduction. But if you contribute to
the world's culture, if you have a good idea, compose a tune, invent a
sparking plug, write a poem, it may live on intact, long after your genes
have dissolve in the common pool" p.199
"We alone on earth can rebel against the tyranny of the selfish
replicators" p.201
12. Nice guys finish first - Prisoners Dilemma, viscosity in
populations, zero sum and nonzero sum games.
"Many wild animals and plants are engaged in ceaseless games of Prisoner's
Dilemma, played out in evolutionary time" p.203
"Two strictly rational players, each of whom assumes that the other is
strictly rational can do nothing but defect if they both know how many
rounds the game is destined to run" p.224
13. The long reach of the gene - Phenotypes, segregation distorters and
meiotic drive, Viroids and plasmids, the Central Theorem of the Extended
Phenotype, the life/dinner principle, reasons for bottlenecked life cycles.
"Our genes co-operate with one another, not because they are our own but
because they share the same outlet - sperm or egg- into the future." P.245
"An animals behaviour tends to maximise the survival of the genes ' for'
that behaviour, whether or not those genes happen to be in the body of the
particular animal performing it" p.253
"When the ways of making a living that are open to small organisms have all
been filled, there are still prosperous livings to be made by larger
organisms. Large organisms can eat smaller ones, for instance, and can
avoid being eaten by them" p.258
3 reasons why a bottlenecked life history tends to foster evolution of the
organism as a discrete and unitary vehicle = 'back to the drawing board',
"orderly timing cycle' and 'cellular uniformity'.
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