Day 063 - The use of religion

Submitted by Sam on 22 July, 2011 - 17:26

We have seen that a value system cannot be genetically encoded, and must be learned. Dennett has postulated that certain religious memes may have derived some of their potency by providing a ready-to-go value system which can help people make major decisions of life, saving them time, energy and angst. In the absence of any systematic way of answering the most difficult decisions, any means of relieving the burden will be seen as very attractive. Sometimes we flip a coin when we can't find a compelling reason to choose one option above another, simultaneously taking the agency of the choice away from us and 'limiting' the consequences of the decision. Devices like coin-flipping are external mechanisms for helping us make small decisions, and devices descended from ritualized practices like divination are ceremonial variants to help us make big decisions.

Divination, one of the precursors to 'domesticated' religion, might have arisen as a manifestation of man's growing difficulties with self-control, providing a way to deal with increasingly larger and increasingly complicated human groups. By reducing the responsibilities involved in decision making, cultural constructs like divination also reduce the possibility of acrimony for bad decisions, creating an external agent which can be held responsible but which will never answer back.

This method of decision making would have aided people in making timely decisions, even if the decisions themselves were not optimal. This can have significant advantages in consolidating resolve and enforcing resolute action. Dennett concludes that divination and its derivatives (like astrology and some aspects of organized religion) could gain currency by affording biological advantages even though the resultant decisions were not based on a source of reliable information, much as a placebo can result in a patient's medical improvement despite containing only medically inert substances. Dennett has also seen that the integrity and thus the utility of such a psychological asset (he refers to it as a 'crutch' for the soul) would be threatened by sceptics, which in turn would motivate a degree of hostility towards non-practitioners.

Day 062 - Domesticated religion

Submitted by Sam on 22 July, 2011 - 02:16

Dairy cattle are our products, crafted through generations of selective breeding for very specific purposes. Through this process of domestication the cattle's genes have come to serve our needs over those of the cattle themselves, creating cattle optimized for us and entirely reliant on our stewardship. Other animals, like barn swallows, pigeons and squirrels, haven't been deliberately domesticated but have evolved a similar kind of dependency, evolving by natural selection to exploit the human environment and live in our close proximity. Daniel Dennett has suggested that religion may have evolved in an analogous manner.

Organized religions, like domesticated cows, are brilliantly designed products with a long evolutionary history. In Dennett's speculation, today's organized religions are 'domesticated' descendents of 'wild' folk religion, much as cows were domesticated from aurochs, their wild ancestor. In their wild form, religious memes existed as superstitions which existed only to make more of themselves, just as aurochs existed to serve the biological imperative of making more aurochs. These wild memes insensibly got themselves domesticated, acquiring stewards willing to devote their lives to helping them flourish; followers of domesticated religion consciously strive to aid their propagation. Just as domesticated animals received a tremendous fitness boost (as measured by their relative global biomass) through domestication, so religious memes prospered by evolving adaptations which produced willing and conscious stewards of them. These adaptations include many individual memes which come together to create a mutually supportive and self-reinforcing complex, making up the entire Catholic church, for example.

Whilst this view of the evolution of religion has been criticized by atheist-turned-theologian Alistair McGrath, who has cautioned that Dennett's arguments are wholly speculative, lacking a scientifically sound body of evidence, Dennett has countered that the purpose of his theory is to explore the question of what religions are and where they came from, rather than provide a definitive answer to it. Whatever they are, they are brilliantly designed, and the more we can understand their design (through whatever theoretical lenses possible), the more we might be able to revise and optimize this design, just as we have done with dairy cows.

Day 061 - Deathly dangerous memes

Submitted by Sam on 21 July, 2011 - 02:05

The Lancet liver fluke is a tiny parasite that spends its adult life in the livers of ruminants like cows and sheep, having passed through snails and ants as a juvenile. When one of these ant eats an infected snail's slime trail, it ingests many juvenile flukes which will move through the ant's gut and throughout its body. Many will find themselves in the ant's main body cavity, where they will mature, but one fluke will move into the ant's brain. Settling in a cluster of nerve cells below the ant's oesophagus, this fluke manipulates the nerve cells to control the ant's behaviour, forcing it to climb to the top of a blade of grass night after night, making it use its mandibles to grip firmly to the tip. By hijacking the ant's brain, the lancet fluke uses the ant as a vehicle to get to a position where it will be likely to be eaten by a grazing animal, thereby bringing the fluke population to their final host, the cow or sheep, where they will mature into their adult form. This hijacking makes the ant into the flukes' own survival-machine, piloted for the propagation of the fluke genes at the expense of the ant's own life.

The philosopher Daniel Denett has used this parasitic mind-control as a particularly vivid analogy for the effects of the most powerful memes, which hijack human minds for their own ends. Some memes, like 'freedom', 'justice', and 'God' are as powerful as the fluke's effect on the ant, and have driven huge numbers of people to die in their service. Memes, the new replicators, have the power to subordinate our biological imperatives, resisting our genetic interest which has driven evolution for millions of years, in favour of other interests which can have negative effects on our genetic fitness.

We are vectors for memes, and some of our memes are worth dying for. When one meme complex collides with another, there is a competition which can be seen as a dire threat. When one of these meme complexes is powerful enough for its host to be prepared to die to defend it, genetic fatalities will be the meme machine's collateral.

Day 060 - Cultural evolution

Submitted by Sam on 20 July, 2011 - 00:50

We have seen that the architecture of our brain includes structures specifically optimized for the simulation of observed behaviour, allowing us to mirror other people's point of view. We have seen VS Ramachandran conjecture that the development of culture was closely bound to the evolution of these mirror neurons, as imitation allowed skills to be transferred across the generations. This neural basis for the basic ingredients of learning, culture and language systems is, of course, encoded by genes – the biochemical replicators that make copies of themselves every time a cell divides, and which when expressed translate into proteins which create vehicles (i.e. bodies and their behaviour) to differentially aid their own replication. But with the development of the mirror neuron system (and whatever other necessary neural structures), genes have created a brand new substrate for replication, in which a brand new kind of replicator is able to achieve evolutionary change at a vastly accelerated rate. Identified by Dawkins in The Selfish Gene, this new substrate is human culture itself.

Dawkins defined the new form of replicator as the meme, a way of thinking, whether a clothes fashion, a particular tune, a catch phrase and so on, which propagates in the 'meme pool' by a process of imitation, copying itself from brain to brain. Particularly fertile memes parasitize minds, turning them into vehicles for their own self-propagation, just as a scientist hears of a good idea and cites it in his articles and refers it to his students and colleagues. As memes can be expressed as physical structures, as particular electrochemical patterns in brains, they can be seen to quite literally replicate many times across populations as they disseminate, undergoing mutations just as genes do. The most potent memes will persist for generations the world over, physically replicated in the brains of many millions of people.

Memes have a survival value, and have to compete for the resources of the human brain. The principle resource a meme contends for is time, competing with rival memes to dominate the attention of the human brain, and become 'successful' by being transmitted to other brains through spoken word, advertisements, books and so on. Some memes will exploit particular evolutionary niches where they become phenomenally successful for a very short period of time, like pop songs and twitter trends, whilst others have a very high survival value, and may last for thousands of years.

One of the most persistent memes (or more accurately, meme complexes) that Dawkins has famously focused his attention on is that of religion, which has had a great stability throughout all human cultures for many generations. The superficially plausible answers that religion provides are highly infectious, offering a buffer against human inadequacies which provides real comfort in the face of deeply troubling questions. Successive generations have been faced with the same troubling questions, and so the God meme has been copied many times over.

Day 059 - Evolutionary arms races

Submitted by Sam on 19 July, 2011 - 00:56

Co-evolution can engender an arms race between competing genes, as predators adapt to better catch their prey and prey correspondingly counter-adapt to better evade their predators. Each genetic lineage 'races' against the other, progressively improving and counter-improving over many generations, always trying (in so far as a gene that produces a particular protein which has some effect on behaviour or morphology can be said to 'try') to out-compete the rival. A common-sense example is the asymmetric genetic arms races between cheetahs and gazelles, where one evolves adaptations which tend to make it better at chasing whilst the other consequently co-evolves adaptations which favour a greater evasive ability. A symmetric arms race occurs in the height of trees in a forest, where the selection pressure for access to light tends to cause trees to grow taller, amongst other adaptations.

These intuitive examples are inter-species arms races, but there are subtler, more insidious intra-species conflicts, even between the sexes. One interesting example is provided by the powerful effect a male canary's birdsong has on a female canary's reproductive behaviour; she initiates nest-building behaviour and increases the size of her ovary when she hears it. This has been shown to happen even when the stimulus is only a recording of a male canary's song, suggesting that the song acts like a drug, manipulating her to be primed for the male's advances. One reading of this phenomenon is that the male has 'won' an arms race, manipulating the nervous system of the female to his own ends, using his song to create an electrochemical pattern in her brain, which in turn stimulates her pituitary to synthesize the required hormones to bring her into an appropriate reproductive condition. Alternatively, the female may exhibit this behaviour as a counter-adaptation which requires the male to give an exhaustive performance of his song before she is willing to mate, signalling that he is a robust partner and one that is willing to commit time and energy to the relationship (having already spent time and energy wooing with a song).

Day 058 - Choosing a mate

Submitted by Sam on 17 July, 2011 - 18:48

As far as the male's genes are concerned, the best strategy for propagation is to mate with as many females as possible, always abandoning one for another and forcing them to bring up his children themselves, affording him more time to mate by never having to expend resources in childcare. This strategy is only possible if the population of females permits it; if the majority of females choose instead to withhold mating until the male completes costly courtship tasks, he would never be rewarded for desertion as he would always face a repeated series of time and energy consuming trials before being able to mate again. Conversely, this strategy is unstable if there are many loose females in a population, as a male would always have someone to run to having deserted his mate.

Female elephant seals permit the male strategy 'mate with and abandon as many females as possible'. However, their social structure ensures that only one bull mates with the harem in any season, leaving the rest of the males with only opportunistic copulations when he is otherwise engaged. The other males will only stand a chance of spreading their genes if they can defeat this alpha bull in fighting, and become the leader of the harem themselves.

This subjugation by a single dominant male may have originally arisen through discrimination on the part of the females, who could have refused to copulate with all but the 'best' males, those who bore visual indications of carrying 'good' genes, that is, genes which confer survival advantages, like strong muscles or big, sharp teeth. By breeding only with these select males, females would increase the survival prospects of their children, and simultaneously benefit her own genes and creating a selection pressure for males with visual indications of health and strength, or promoting sexual attractiveness itself. As the females will be judging the males on the same criteria, only a few of them will be selected for breeding, and these will be those with characteristics that equip them well for fighting, or defending their mating rights from rival males: the harem structure is born.

Although not obviously the case in elephant seal populations, females selecting mates on the basis of physical indicators of survival prospects can create a selection pressure for males with these attractive qualities, whether they are actually useful for physical survival or not. The elaborate tails of the male birds of paradise, for instance, may have evolved this way: longer tails may initially have carried some indication of a male's health and ability to find food, and thus the suitability of his genes to create strong, healthy children. After generations of selection for bigger, more extravagant tails, males may actually have been left with tails so large that they became a physical disadvantage, possessing them merely because they were attractive to females, and no longer functioning as a truthful indication of physical prowess.

This is a self-reinforcing cycle, because if long tails were considered by the majority of the female population as desirable, any female mating with a male with a shorter tail would stand little chance of her own son being regarded as a potential mate, and therefore she would disadvantage the spread of her own genes. In this way, genes set a standard for sexual attractiveness which it pays to stick to.

Day 057 - Differences between the sexes

Submitted by Sam on 17 July, 2011 - 01:11

Relative to each other, males tend to produce small sex cells and females tend to produce large sex cells; sperm are small and many, eggs are large and few. Apart from being one of the most convenient ways of distinguishing males from females in both animals and plants, this difference in gamete size is symptomatic of a fundamental asymmetry between the sexes. Each sex has to establish a compromise between time and energy spent raising children to ensure they are healthy and that their genes will continue to propagate, and time and energy spent fighting with rivals for mates and other resources, to maximize the number of children containing these genes. If one sex is to settle on a different balance between these two opposing needs, perhaps initiated by a difference in resource allocation so slight that it arose at random, it is likely to be selected for so that parents who are successful in fighting breed fighters who benefit their genes more from fighting more than parenting, and vice versa. This selection will naturally lead to an escalation in differences until one sex achieves reproductive success primarily through investing in parental behaviour whilst the other ensures their reproductive success primarily through fighting rivals to mate with the most.

This difference is apparent right from conception, where the unequal size of the male and female gametes informs an uneven distribution of resource investment in the child in the earliest possible stages – the male has invested less than his fair share of half of the necessary energy to produce the fertilized egg, whilst the female has had to invest comparatively heavily in her large, energy-rich egg. Whilst both parents have contributed an even number of genes to the child, their sex cells contribute an uneven share of resources.

Unconsciously impelled by their genes, parents try to exploit each other to invest more than their fair share in their child. It is advantageous, from their gene's point of view, to let the other half do all the work and take the burden of child rearing, allowing the shirking parent more time and energy to pursue other sexual partners, and thereby spread more copies of their genes. The basic characteristics of the male sex cells reflect this disparity, as many small, fast sperm allow him to potentially sire many more children than a single female could raise. As eggs are larger than sperm, the female is evolutionarily exploited at the earliest stage, and she is placed in the position where she must invest more in the child's rearing than the male. In mammals this is especially pronounced, as the mother must incubate the foetus herself, feeding it from her own body, investing more than the father and therefore becoming more 'committed' (resource-wise) to the child. She stands to lose much more from the loss of the child than the father does, and is therefore much less likely to abandon the child when it is born. The father, who has much less to lose if he abandons mother and child, will have more time and energy to fight for another mate and beget more children if he does so. There is a battle between the parents as to who deserts first, and who can get away with the least amount of parental investment.

Perhaps the only option the female has to redress this unfavourably weighted balance is to refuse to mate with the male until he pays a high price for her prized commodity, her large, nutritious egg for his child, making him invest time and energy in her and the unborn child before conception. Such pre-copulation investment take the form of courtship rituals, and include nest building and offerings of substantial amounts of food. By extracting a price for mating, the female is in a position to tie the male in through his investment, perhaps decreasing the chances that he will desert after mating, and instead continue to devote himself to the well-being of his child.

Day 056 - Favourite children

Submitted by Sam on 15 July, 2011 - 21:10

As far as proportions of genes are concerned, there should be no reason why a parent should invest more time and energy in one offspring rather than another, as each parent has the same relatedness to their children. Although it would seem that a parent might best serve the proliferation of their genes by investing equally in all of their children, there are invariably differences in life-expectancy between a range of offspring, and some are better bets than others. Despite containing the same proportion of their parent's genetic material as their siblings, undersized or otherwise disadvantaged children (or runts of litters) have a much lower life expectancy, and so would require a greater than normal parental investment just to be given an equal chance as the more advantaged children. In such cases, it may be worthwhile for the mother to invest more in her other children and refuse to feed the weakest child, instead spreading its allocation of 'parental investment' to the other children. Following this line of reasoning to its logical conclusion suggests that the optimum strategy might in fact involve eating the runt, or feeding it to its siblings in order to reclaim some of the lost investment in energy.

This imbalance creates a tension between the generations, as children endeavour to manipulate their parents in order to receive more than their fair share of investment, whilst parents must endeavour to identify such exploitation and allocate resources in the most (genetically speaking) efficient way possible.

Day 055 - Selfish and selfless

Submitted by Sam on 15 July, 2011 - 01:04

Whilst a gene for saving close relatives from death (even at the expense of your own life) could theoretically spread in the gene pool, it could only be successful if its bearer is actually able to identify its close relatives, which is not necessarily an easy task. One way for an organism to recognize its kin with some degree of reliability would be to remember other members of the species who share a physical resemblance to them. A gene encoding the behavioural equivalent of 'be nice to those who look like you as they might be your relations' would generate the kind of altruistic behaviour that would mutually support the spread of selfish genes shared through different bodies.

In some species that stay in small groups or who do not move around much, there is a good chance that any member is closely related to another, and so genes which tend to promote altruistic behaviour towards any member of the same species may tend to spread through the gene pool, as any possessor would be more likely to look out for other possessors than not. Dawkins offers the example of a male baboon defending its troop from predators, risking its life to protect the genes which are statistically probable to be invested in other members of the group, which may contain many close relations.

However, no matter how altruistic the behaviour encoded by genes is, it can never be as strong as the encoded propensity towards individual selfishness, simply because your genes can only ever be completely certain of your own individual identity, whilst altruistic genes can never be sure to completely recognize close kin, as they are susceptible to errors in classification and, may mistake perfect strangers for close kin.

Day 054 - Dying to save your family

Submitted by Sam on 13 July, 2011 - 22:34

The most extraordinary thing about genes is that they can programme their survival machines to behave in seemingly altruistic ways, even to the point of that machine's self-destruction. A particularly extreme example would be an individual sacrificing itself in order to save the lives of others. Dawkins' selfish gene theory gives an insight into how such an apparently altruistic trait could develop to the gene's advantage by showing that the closer the genetic relationship between two individuals the more sense it makes for them to behave altruistically towards each other, as each will be statistically likely to be carrying a good proportion of the other's genes.

As close relatives have a greater average chance of sharing genes, it could conceivably benefit the spread of a particular individual's genes if it died in order to rescue ten close relatives from drowning, for instance, as it would be likely that whilst one copy of the 'kin-altruism' gene would be lost in the process, many more may be preserved through the apparently selfless act, thereby increasing the 'save close relatives from drowning, even if it kills me' gene's prevalence in the gene pool. It should be cautioned that there is of course no such gene, merely a gene which, when present and expressed in the complex matrix of other genes in a body, induces a greater than usual tendency to save people from drowning than if it were not present or expressed.

Crucial to an understanding of this example is the fact that whilst such a gene may be rare in the wider population, it is likely to be common within a family. There is a 50% chance that your siblings contain the same particular rare gene that you do, as they would have received the gene either from your father or your mother. This means that the 'relatedness' between two siblings is ½, since on average, half of the genes each has will also be possessed by the other. The relatedness between a parent and a child will always be exactly half (barring any mutation), because the process of meiotic division ensures that 50% of a child's genes are received from its father's sperm and 50% are received from its mother's egg. An individual's relatedness to itself is 1, because it can be sure it has 100% of its own genes.

Through this index of relatedness, it can be shown that a gene for suicidally saving five of your cousins (who each have a 1/8th relatedness to you, producing a total relatedness of 5/8ths) will not spread throughout the gene pool, whereas a gene for saving five brothers (each with a ½ relatedness, totalling a 2 ½ relatedness), or ten cousins (1 2/8ths) would spread throughout the population. This is because a suicidal altruistic gene only has to be successful if it can save a minimum total relatedness of more than 1, because this is the total (arbitrary) 'value' of the genes which will be lost through the altruistic suicide. If a gene can, on average, save more than a minimum of two brothers or sisters or parents, more than four uncles, aunts, grandparents (and so on), then it will persist in the bodies of the saved individuals with a frequency great enough to compensate the loss of the altruistic individual.

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