Summary of Chapters 4 & 5 of “the Mating Mind”

Prepared by jessica aragon, ryan Michelson, & Salina Zapata

 

 

 

March 20, 2002

 

 

 



Chapter 4:

A mind fit for mating

 

     As Chapter 4 opens of “ The Mating Mind” the author Geoffrey F. Miller describes how there were different ways of achieving the evolutionary task of spreading their genes. He explains that there was the bacterial method of divide and conquer, there was also the cloning- factory strategy. He makes the example that fungi reproduce in this manner and are very successful, except when a harmful mutation arises, because there is no means of getting rid of it. Miller writes that in the last few hundred million years, sexual reproduction has become the third way of spreading their DNA around.  An organism grows a trillion celled body to produce packets of DNA, and tries to find a partner with complementary DNA packets to combine them into an offspring that bear both parents traits. 

COPYING ERRORS

    

In the section entitled, “Copying Errors” Miller confirms that in the beginning of sexual reproduction, most organisms were not very selective. He explains that since most mutations are harmful, organisms developed DNA repair machines to correct mutations.  There are two kinds of copying errors: 1) some errors just don’t look right to the DNA repair machine, and are easily fixed. 2) Other errors look just like ordinary DNA. These pseudo-normal DNA are the problem.  They look okay, but they do not act like good DNA when you try to grow an organism using them. For a species to avoid going extinct as a result of accumulating too many harmful mutations, selection must be able to eliminate mutations at the same average rate that mutations occur, or the species will experience mutational meltdown. Because offspring have two copies of each gene, the normal version inherited by one parent often masks the failures of the mutated version inherited from the other parent.  This is why incest is bad idea.  He says that blood relatives often inherit the same mutations, which are not masked by normal genes when close relatives produce offspring. This masking effect is called genetic dominance. Dominance makes sex very powerful in limiting the damage caused by mutations.  He goes on to explain that dominance is not perfect and is really only a short-term solution. Two normal genes are sometimes still better than one. This is because hiding the effects of mutations allows them to accumulate over evolutionary time.  To keep mutations from accumulating, some offspring will inherit a below-average number of mutations from their father and a below average from their mother too. Therefore, they will have much better genes than the average offspring. Ultimately, these relatively mutation free genes will spread through future generations.  If the opposite occurs, where an offspring inherits an above average amount of mutations, then they may fail to develop at all, or may die in infancy.  But on the positive side, they take with them their large number of genetic mutations in evolutionary oblivion.  This is a very important effect, because it ensures that at least some offspring will have very good genes, and this is what will keep the species working. He explains that as an investment strategy it is better to have fewer offspring that have a chance to do very well, than a larger number of mediocre offspring.

MUTATIONS, FITNESS, AND SEXUAL ATTRACTIVENESS

    

In this section Miller explains that if the goal of sexual reproduction is to keep some of your offspring safe from harmful mutations, then it would be foolish to pick sexual partners at random. He confirms that we should pick the partner with the least amount of harmful mutations.  This decision criterion will give your offspring the highest expected fitness, which means the best chance of surviving and reproducing.  If your choice of sexual partner is very good, your genes may hitch a ride to evolutionary stardom on the genetic quality of your partner. Many biologists agree with Miller that mate choice is essentially a strategy for getting the best genes you can for your offspring.  Dominance is often incomplete, and a lot of genetic variation does show up in body and behavior.  When genes reveal themselves through body and behavior sometimes it can be easier to determine which organisms have complex traits and which do not.  An example is peacock tails, the more complex the gene structure, the more elaborate the tail will be.   And their variation at the visible level of body and behavior means that genetic variation can be perceived during mate choice. 

Fitness Indicators are traits that evolved specifically to advertise an animal’s fitness.  Fitness means the propensity to survive and reproduce successfully.  It is determined mainly by an individual’s genetic quality, which boils down to how many gene mutations they have. Miller explains that because mutations are deviations the genetic norm that are therefore, deviations from the genetic norm.  If a set of mutations makes an individual unable to grow an optimal body and unable to produce optimal behavior, then they impair that individual’s ability to survive and reproduce. He makes the distinction that since fitness means the ability to survive and reproduce, mutations almost always lower fitness; conversely, high fitness implies freedom from harmful mutations. Miller ends this section by stating that Fitness indicators are the connection, for they are the traits that make fitness visible. He says that Fitness indicators are the genetic sieve that lets sexual selection sift out harmful mutations. In this view of fitness indicators, sexual ornaments and courtship behaviors evolve as fitness indicators.

 

The human mind as a set of fitness indicators

 

     Miller starts us off here by recalling that he defined the theory, runaway brain theory in the previous chapter 3.  He explains that it has problems though. It does not explain the trend of hominid brain evolution toward the big and the bright, and it does not work very well with mutual mate choice.  He explores here that what if there is another possibility.  He poses the question as to whether or not the human mind’s most distinctive capacities evolved through sexual selection as fitness indicators. He calls this the healthy brain theory, and contrast to the runaway brain theory by saying that the healthy brain theory suggests that large brains are simply better advertisements of how good our genes are compared to smaller brained apes.  He says that because our brains produce behaviors such as art and language that we may be advertising our fitness to potential mates. Furthermore, our creative intelligence evolved not for survival but actually as a fitness indicator to the opposite sex.  Examples of other species that have developed behaviors as fitness indicators are songbirds, fruit flies and bowerbirds.  Songbirds repeat complicated melodious sings to reaveal their fitness.

     Fitness indicators serve a sort of meta-function.  They sit on top of other adaptations, proclaiming their virtues. He explains that these traits are not helpful in survival or hunting or avoiding predators, instead these traits help to attract sexual partners. In humans, examples would be good senses of humor and artistic creativity, or even morality.

 

Evolutionary fitness and physical fitness

    

Miller says that evolutionary psychology has paid very little attention to the possibility that many of our psychological traits may have evolved as fitness indicators too.  He says that in order to understand it better we must first understand the difference between Evolutionary fitness and Physical Fitness.  He ponders over the difference between what biologists believe to be fitness and what fitness in an evolutionary sense means.  Biologists believe that fitness is a means of surviving and reproducing. Evolutionary fitness has 3 important features: it is relative to competitors in a species, it is relative to an environment, and it is a statistical propensity rather than an achieved outcome.

Evolutionary fitness is relative to a species.  Evolution increases fitness, by definition. In this sense, evolution is progressive:  when sexual selection favors fitness indicators, it necessarily increases fitness and contributes to evolutionary progress. Evolutionary fitness is also relative to environment.  It depends on the fit between an organism’s traits and an environment’s features, which is why he calls it fitness rather than quality or perfection.  Fitness as a propensity is an expectation that allows us to predict how an individual will probably fare.  Fitness is something we attribute to organisms to explain why they survive and reproduce better than their competitors. Fitness in the physical sense can also imply youth, health, athletic ability, and physical attractiveness.  Another contrast to evolutionary fitness is that physical fitness is closer to a measurable achievement than a statistical propensity. It is less abstract, and closer to real behavioral outcomes. Evolutionary fitness is linked to physical and mental fitness by something that biologists call “condition.” Miller says that it is in fact an animals “condition” that is basically its physical fitness, health, and energy level. A high fitness animal may be in poor condition due to a temporary injury or food shortage. The abilities to find food, resist disease, and avoid parasites are major determinants of condition, and major components of fitness. Good condition is a pretty good indicator of high fitness.

A set of chain relationships prove central to Miller’s book. They are genetic mutations influence fitness, fitness influences condition, condition influences the state of fitness indicators, fitness indicators influence mate choice, and mate choice influences evolution. Miller states that for animals making sexual choices, fitness indicators are just proxies for good genes. But the sexual selection that results does not just influence the genes; it also affects the fitness indicators themselves.

This theory of fitness indicators suggests that much of human courtship consists of advertising our physical fitness and mental fitness to sexual prospects. Physical fitness may mean body shape, facial features, skin condition, energy level, athleticism, fighting ability, and dancing ability. Mental fitness may be defined as creative storytelling, intelligent problem solving, skillful socializing, a good sense of humor, empathetic kindness, a wide vocabulary, and so forth.

Miller goes on to explain that he will try to argue that some human mate preferences have been misunderstood as seeking purely non-genetic benefits, when they have actually been focusing on indicators of genetically heritable fitness. 

 

Ms. Fitness USA

 

     Miller says that for him the sexual revolution of the last 20 years has come in the form of the Ms. Fitness USA pageant, as opposed to Ms. America Pageant that was more popular 20 years ago. He says that these more fitness-oriented contests were created in response to the criticism about the stereotypes of the women in the Ms. America pageants. Women said that the ability to totter around in heels and a swimsuit did not seem to reflect any very significant aspect of a woman’s being.  The purpose was to try to show an active display of health instead of a giggly, soft-bodied display of femininity.  The point was to show that Ms. Fitness USA contestants could only win if they trained like professional athletes by doing aerobics, weight lifting, stretching, sports and healthy eating.  The end result is that the ornaments that stick around that have something to do with genes are the ones that should reveal some information about fitness.

Sexual choice for fitness

 

     Miller starts this section out by telling us about Sir Ronald Fisher and how he first emphasized that animals could choose their sexual partners for high fitness by favoring certain kinds of sexual display. The “lek paradox” is the most extreme case of a general problem with the heritability of fitness.  Any form of sexual selection for fitness indicators should even out genetic variation in fitness.  If female choice in our species favored tall males, all males would be equally tall.  This is an example of how if everyone chooses the same traits in their sexual partners then these traits become the norm in all humans.  Once biologists agreed that the lek paradox was a problem, the hunt was on for the evolutionary forces that could maintain variation in fitness.  Two major candidates emerged.  One emphasized that fitness is environment-relative; the other emphasized that the ubiquity of harmful mutations that erode fitness. 

     Fitness fluctuates according to changes in the environment and species adapt fairly quickly to those changes.  More importantly, however is the species interaction with surrounding parasites. The capabilities of parasites to determine what counts as fitness for the host, because parasites can evolve much faster than their host, there is no hypothetical situation in which every individual has high fitness. This arms race between parasites and hosts could maintain the incentive for mate choice. While this may explain why physical fitness and health remains heritable it does not explain why there is such variation in mental adaptations.

The balck Rain of Mutation

 

                        Mutations do undermine normal appearance and attractiveness, but they rarely bring survival or fertility benefits.  Many biologists hold the view  that fitness remains heritable mostly because new mutations are constantly arising and causing trouble.  To avoid mutational meltdown, and extinction selection had to be potent enough to eliminate those mutations.  Very rarely does selection favor a new mutant, because only rarely is a mutated gene better than the existing gene at helping an organism survive and reproduce.  These rare occasions attract the biologist’s attention because they are the times when evolution-genetic change in a species--- can occur.

 

 

 

 

 

 

The Brain as a Target for Mutation

 

The more complex a trait is the more genes there are that are vulnerable to mutation.  This means that a very complex trait like the human brain is an excellent fitness indicator because there are thousands and thousands of genes that may contain mutations.  Because fitness has the ability to be inherited mate choice is our method of flushing out those mutations. 

 

How to Advertise Fitness    

 

Fitness indicators are necessary because mates will whenever possible lie about their fitness.  One way to determine fitness is through an idea called “conspicuous consumption” which means that a mate will ornament themselves with costly luxuries in order to advertise their fitness.  This is one of the only ways to advertise true fitness because it cost a lot of fitness to produce the signal.  For example a peacock’s tail is heavy, costly, and cumbersome.  Therefore only the fittest peacocks can afford to have large, extravagant tails.  Most sexual ornaments are therefore handicaps that advertise true fitness by handicapping an individual with survival costs.  “Why should a man give a woman a useless diamond engagement ring, when he could buy her a nice bit potato, which she could at least eat (124).”  The more it cost the individual the better of an indictor it is.  For example proclaiming, “I have a straight flush” in poker carries less credibility than placing a large bet on one’s hand.

 

Advertising Within One’s Budget

 

Because fitness indicators are handicaps, most sexual ornaments are not produced by all males to equal degree.  “Better fed animals can afford to grow larger sexual ornaments.  Most energetic animals can afford to exert more effort in courtship.  Stronger animals can afford to fight other strong animals in ritualized contests.  Faster animals can afford to taunt predators from a closer distance (127).”  But all animals are not forced to have a sexual ornament that will in the end exhaust them and kill them. 

 

An Infinite Variety of Waste

 

“The acts of love considered most romantic are often those that cost the giver the most, but that bring the smallest material benefits to the receiver.”  The form of the waste is not necessarily what is important rather the amount of waste is the key factor. 

 

Evolving Better Indicators

 

In Rowe and Houle’s model all fitness indicators start out as ordinary traits.  Once an ordinary trait is favored by the opposite sex those with costlier versions of that trait have a better chance of reproducing.  “The sexual selection also puts pressure on the trait to recruit a larger share of the individual’s energy budget for itself (130).”  In this way, sexual selection has turned an ordinary trait into a really good fitness indicator.  No only does it recruit more energy but it also recruits a larger percentage of that individual’s genes.  “This might mean that when sexual selection seized upon the ape brain as a set of possible fitness indicators, the genic capture process recruited a lot of pre-existing brain circuitry into human courtship behavior (131).”  This means that human mental abilities might be so complex because they are so efficient at advertising the brain’s mental abilities.

 

Mental Traits as Fitness Indicators 

 

Human mental traits that evolved through natural selection for some specific function show small differences between people because selection should have eliminated bad variations long ago.  But mental traits that evolved as fitness indicators are just the opposite; showing large differences between people.  “If a human mental trait shows large individual differences, high heritability, high condition-dependence, high costs, and high correlations with other mental and physical abilities, then it may have evolved through sexual selection as a fitness indictor (133).”  This does not mean that all mental and physical adaptations evolved because of sexual selection.  Probably 90 percent came from natural selection and social selection to solve routine daily problems of living.  But the remaining 10 percent like music and art have a pretty good chance of being products of sexual selection.

 

The Hominid That Wasted Its Brain

 

“Our brains are only 2 percent of our body weight, but consume 15 percent of our oxygen intake, 25 percent of our metabolic energy, and 40 percent of our blood glucose (134).”  Our brains cost a lot of energy and effort to run.  Sexual selection stretched the capacities of our mind to find new innovative ways of showing good fitness.  “It is asked not what a brain can do for its owner, but what fitness information about the owner a brain can reveal (135).”

 

Are Fitness Indicators Immoral?

 

It seems immoral to say that everything that we value about humanity has evolved to proclaim one message: “I am fit, my genes are good, mate with me.”  But look at it this way; social norms or morality is developed to minimize the social costs of advertising one’s fitness.  “We value humility precisely because many people are unbearable braggarts who try to flaunt their fitness indicators so relentlessly that we cannot hold a decent conversation.  We value frugality because so many people embarrass everyone with their ostentatious displays of luxuries, and waste limited resources that others need.  We value egalitarianism because it protects the majority from aspiring despots intent on power and polygyny (136).”  Our moral values may in fact just be adaptations.

 

 

Chapter 5

Ornamental Genius

 

 

Because sexual choice is relayed via the senses sexual ornaments have evolved as sound and light shows designed for sensory appeal.  But as humans we have communication systems that through language are able to convey complex ideas.  This means that sexual selection is able to play on that.  “The mind could be viewed as an entertainment system that appeals to the psychological preferences of other minds (138).”  Even consciousness itself may be a sexual ornament.

 

The Senses as Gatekeepers

 

Like burglars learning about the security systems of banks, animals evolve courtship strategies to sneak through the senses of other animals, through the antechamber of their decision-making systems, into the vault of their reproductive potential (140).”   In 1978 Richard Dawkins and John Krebs produced a paper that argued that when animals send each other signals, they are selfishly trying to influence each other’s behavior. 

The senses have multiple functions therefore they cannot be perfectly adapted to mate choice.  For example because primates eat fruit they have developed visual systems attracted to bright colors.  If a male primate happens to evolve a bright red face, he might prove more attractive to females.  The female senses are biased to notice bright colors and this influence is coined “sensory bias.” 

 

Sensory Bias

 

This may allow us to predict some of the paths that sexual selection will take.  “Finally, sensory bias theory, recognizes that senses evolve interactively with the signals they favor (142).”

 

Displays Match Senses

 

“The senses used for mate choice in each species tend to be well matched to the sexual ornaments displayed by that species (142).”  For example in several species of Central American frogs the female ears are the most sensitive to auditory frequency of male courtship calls.

 

Senses as Engineering Compromises

 

One claim to sensory bias theory is that certain features evolved because they are the most in tune with our ability to perceive things in our world.  Advanced visual systems as those in humans are the most excited by symmetric patterns.  This explains why sexual ornaments like stars, sunbursts, and eyespots are so popular.  But sexual ornaments may be so unpredictably diverse in different species because a new sexual ornament may excite the senses in a way that could never have been predicted. 

 

From Sensory Appeal to Sexual Appeal

 

But just because an individual grabs the attention of a prospective mate through stimulation of their senses doesn’t necessarily mean that they will then have sexual appeal.  “Animals usually respond more strongly to visual ornaments that are large, brightly colored, and symmetrical, and to auditory ornaments that are loud, low in pitch, frequently repeated, and sampled from a large repertoire (147).”  Only the healthiest animals and those with the best fitness can produce these ornaments.  Thus sensory bias is tied into adaptive strategies for mate choice.

 

Tickling Senses Versus Advertising Fitness

 

“Sensory bias theory reminds us that mate choice is mediated by perceptual abilities, and that as new perceptual abilities evolve, the way is opened for new kinds of sexual ornaments to evolve.  With the evolution of bird ears came the possibility of bird song (148).”

 

Pleasure Seekers

 

Consider two hypothetical types of brains wired for mate choice: the cold chooser and the hot chooser.  The cold chooser compares prospective mates through a mathematical procedure and simply chooses the better.  No pleasure is derived from doing this.  It is suspected that most insects work like this.  In contrast the hot chooser chooses a mate by the way in which that individual gives them subjective feelings of pleasure.  The more pleasure a potential mate arouses the more likely that individual is chosen.  In this hot chooser every decision is mediated by this pleasure meter even those decisions that are needed for survival.  A pleasure meter like this would be useful in telling an individual to do more of what gives them pleasure.  “For this reason, pleasure-giving courtship behavior is probably a better fitness indictor than courtship that merely activates sensations (152).”

 

THE PLEASURE METER

This article has a lot of focus on the pleasure-meter which lies in mostly all species. These species utilize this pleasure-meter to select mates to their best benefits possible. This puts the courters in competition with each other to have the sexual partner of their choice. They work harder at providing pleasure for the female they are courting. A major issue in who the female selects to mate with is that they are choosing someone who is best fit to grant good genes upon any offspring that comes about from the mating process.

Miller explains the pleasure-meter as not always being an issue in mating species, rather it evolved and came about according to the complexity of the brain. The brain tells the species that it enjoys something, is pleasured by something, and it signals it that this act is something worthy of repetition. For example, eating is something that brings pleasure to a species, this pleasure is a reinforcement to do it again, in order to feel that same pleasurable feeling. Not only would the species repeat the eating process, but also would repeat the choosing process of what exactly it eats. As far as mating goes, this is where the selection ties in to the pleasure-meter. If a mating partner supplies the female with great pleasure in the mating process, then the female will reinforce the same strategies that she went about before in choosing her next mating partner. If satisfaction is not brought upon by the particular mating partner she has chosen, then the learning process continues to cycle in that now she will go about different strategies to select a mating partner.  This is a very beneficial concept in that it allows females, who have a great concern for their offspring and the qualities that their offspring contain, to select a mate that will best provide good genes for their offspring to be fit and endowed with great pleasure providing qualities.

An issue that is faced in the process of the pleasure-meter is the fitness of the male who is courting the female. The providing of pleasure says nothing about the whole genetic make up of the male because the pleasure-meter cannot even guarantee the honesty of itself! So the question now is: Is this a cost for the female in the long run? Will her offspring, instead of having good genes passed on by the other mate, have bad genes because of the manipulation that was used in the providing of the pleasure in courting? Well, no, of course not. The genes and fitness that are being avoided by the female in selection of a mate are very apparent in that particular courter. Therefore, those qualities will not be able to be avoided and the female will not be able to overlook them. The pleasure systems are very sensitive to variations in mating partners, which would allow them to be aware of a bad quality. This makes the manipulation of some courters who know what a female is looking for, so provide it, be not such a bad cost for the female in the mating process.

THE ORNAMENTAL MIND

 

The human mind is a complex subject and has been analyzed by so many to be compared to various things. It can be “a set of survival abilities”, “a computer”, “a Swiss Army Knife”, “a Machiavellian intelligence center”, or a new concept that many theorists have become fond of which is “the entertainment system”. The entertainment system allows the mind to be attracted to various types of qualities that may lead to us preferring one mate rather than the other. The qualities that we may be attracted to may be very complex, whereas certain pleasure-giving courters might only touch upon the superficial interests that we may have.

This entire concept of the mind is the Ornamental Mind Theory. This is very complex in the description of the mind, whereas before in time, we were dealing with metaphors such as the mind “as a computer”, which in this day and age, is eliminating most of human life as an important aspect. The mind as an entertainment system is very precise in touching upon the things that are important to us according to evolution. As an entertainment system, the mind’s primary concern is to stimulate the brains of others. This is where the pleasure-giving comes into play. They become an individual who appears to others to be the best fit for mating and passing on good, fit offspring. If they can stimulate the brains of others, than they have the ability to open a door for a possible mate and this benefits them since they are the ones looking for a mate initially in that they are trying to pleasure others. The mind as an entertainment system reflects popular taste according to the time and evolution. This popular taste will be attracted if stimulated by an individual, in turn wanting a mating partner to pass on these traits and abilities to please. Sexual selection is very different from survival of the fittest, and this is very apparent through the selection process in that it is clearly a matter of what appeals to us of the possible mate, rather than what will keep us alive. If it was a matter of what would keep us alive, we wouldn’t care what kind of genes we had, let alone our children! Instead we have a concern for who fathers our children, not domestically, but biologically. We want our children to be of the best, and that can only come to if we partner up with the best mate possible to create them. It is not about having to ponder the idea either. The thought of wanting the best genes for our children is intuitive and inherent in the individual. We all want the best, and in order to get it, we must mate with the best. The “best” varies for various individuals, according to what appeals to them and what they are attracted to.

THE SPACE OF ALL POSSIBLE STIMULATION

The aspects of an individual that different individuals appeal to can vary from one person to the next. This is the reason that the entertainment industry, in reference to our minds, is seen as an exploration of the “space of all possible stimulations”. Every person is different from the next. This makes it very difficult to predict what a specific individual will like and be pleasured by. The human brain is able to stimulate others however it does not have premature knowledge of what exactly will stimulate it in the correct manner. Without competition however, there would only be opportunity for mutual selection. This would in turn cause no evolutionary progress among our species. Instead the same genes would be passed along in the same manner, without ever encountering variation. Pleasure will never increase from one generation to the next.

 

PUTTING PIECES TOGETHER

 

Some sexual ornaments do not vary from generation to generation. They simply pass on from our ancestors to us in a very ordinary fashion. The runaway theory, the indicator theory, and the sensory bias theory all tie in together. Runaway occurs, according to Miller, because sexual preferences become genetically correlated with the sexual ornaments they favor. The indicator theory occurs, in his eyes, because it is the source that sexual selection will gain direction from. They all tie in when it comes down to sensory biases. Miller explains that sensory biases influence where runaways are most likely to go and which indicators will most likely evolve.

 

HOW ORNAMENTS AND INDICATORS INTERACT

 

     Indicators portray a particular quantity, a constant number or quality that is consistent in any situation. The ornament is the way in which the indicator is portrayed. Geoffrey Miller uses the analogy of the car and the meters on the car to compare the indicator and the ornament. He states that the indicator would be like the speedometer and the ornament would be like the various types we see among various styles of cars. Miller ties in the handicap principle to explain how the design of the human is much more complex than that of a speedometer or a watch. Because as far as the human ornaments go, they are so unique and cannot be replicated easily. He compares humans to that of a coin, which is so precisely created to the degree of not being copied sufficiently. After any species developed mate choice as an option in lifestyle, then every species would be capable of selection in the fitness of a mate, thus the fitness indicator.

 

SEXUAL SELECTION, NATURAL SELECTION, AND INNOVATIONS

 

Sexual selection can interact with natural selection and create innovations. This is a result of evolution on a higher degree and level. The doors are opened for new things, resulting in the exploration of innovative ideas, in turn ending with “adaptive radiation”. Miller explains this concept with the example of an ape. The ape has evolved into many various types of species, including the human itself. Miller explains that every single class or family has a greater history that is brought from an innovation. There are macro and micro innovations that may exist. These innovations are determined according to the negative effects or the positive effects. There are many issues involved in the development of innovations that will be valuable. The metaphor that Miller uses is that of Microsoft and how it needs all of its employees in order to have been successful and they all need each other to work together.

 

THE THRESHOLD OF INNOVATION

     

     The beginning of innovations do not show immediate results, therefore leaving the problem of why natural selection would favor the innovations occurring. When an innovation occurs, it should occur so that the evolution can have a good result, however natural selection cannot foresee this benefit. Therefore, how can natural selection work together and favor this idea of innovation, without having doubts and questions? This is where Darwin’s theory of evolution by natural selection is opposed. The only way an innovation can provide benefits is once they have been applied. In applying itself, an innovation can pass a threshold, therefore being favored by natural selection. However it takes a while for an innovation to pass this threshold, therefore it causes confusion as to how it is favored by natural selection. The only type of innovations that can possibly be understood as to how they were favored by natural selection is those that happened gradually. Miller discusses the opposition of the opinions of theorists Dawkins and Eigen, who suggest that these major innovations could have happened step by step. The problem with the threshold effect is that the costs come early and the benefits come later, causing much frustration by nature because it cannot foresee the future benefits that are to come. Nature cannot bear costs while they await the benefits either, because they need to have a constant profit in order to avoid extinction.

 

SEXUAL SELECTION AND VENTURE CAPITAL

 

     Evolution has no form of venture capitalist. It has no support system in the actual evolution that leads to innovation. It has no way of knowing that if it falls through, everything will still be alright. The species takes a risk of becoming extinct. In turn, sexual selection is a working venture capitalist. It can favor an innovation because of the ornaments it holds. It will support them with reproductivity, therefore the costs will not be as great as without that. Miller explains this to still be very risky, however it is a risk that is well worth taking. The only real profit that is guaranteed is the profit of confidence that is built upon the individual species itself. This confidence can be broken by the extinction of the species, however this is something that is not expected.

 

WHY IS EVOLUTIONARY INNOVATION OBSESSED WITH MALE GENITALS?

 

     Male sexual ornaments along with it’s genitals are the most distinguishable traits for most species that are from closely related members of the same genus. When one species splits off from another, the male genitals are the first thing to diverge. Innovation has occurred a lot among the shape of the male’s genitals. The male genitals are more specific in identifying what species they are, whereas the female genitals can only get as specific as the genus that she belongs to.

 

INNOVATION THROUGH SEXUAL CHOICE

 

     The many courtship benefits that exist can have a lot of survival benefits as well. They, then become very valuable because they contain various benefits to the lifestyles of the species. These become innovations that are very beneficial and crucial to the species. An example that Miller utilized to explain more clearly the meaning of this was the example of the feathered wings of a bird. Their feathered wings have innovated to become beneficial as far as mating and survival was concerned. Sexual selection is the primary way to lead to innovations without confronting the threshold problem. The human mind, according to Miller, is one of these innovations that has benefited us in both ways, the sexual selection aspect of life, and the survival aspect of life.

 

FROM A PRODUCTION ORIENTATION TO A MARKETING ORIENTATION

 

     Rather than the selection of a species for a mate to be from scratch and without any advertisement, the species does as a Marketing Orientation in that it focuses on the preferences of the possible mates it encounters. The species realizes that it has to satisfy the consumer, which is the mate, in order to gain profit. This means that the whole existence of a species would be important as far as pleasing the mate.

 

 

 

 

Outline

I.                  Copying Errors

A.    Organisms develop DNA repair machines to correct mutations.

B.    There are two types of copying Errors:

·        Some errors just don’t look right to the DNA repair machine, and are only chemical nonsense, and are easily fixed.

·        Other errors look jut like ordinary DNA. These pseudo-normal DNA are the problem.  They look okay, but they do not act like good DNA when you try to grow an organism using them.

 

C.    Selection must be able to eliminate mutations at the same average rate that mutations occur, or the species will experience mutational meltdown.

 

D.    Strategy it is better to have fewer offspring that have a chance to do very well, than a larger number of mediocre offspring.

 

II.               Mutations, Fitness and Sexual Attractiveness

A.    That we should pick the partner with the least amount of harmful mutations.  This decision criterion will give your offspring the highest expected fitness.

B.    Fitness Indicators are traits that evolved specifically to advertise an animal’s fitness.  Fitness means the propensity to survive and reproduce successfully. 

C.    Fitness indicators are the connection, for they are the traits that make fitness visible. Fitness indicators are the genetic sieve that lets sexual selection sift out harmful mutations.

D.    In this view of fitness indicators, sexual ornaments and courtship behaviors evolve as fitness indicators.

 

III.           The Human Mind As a Set of Fitness Indicators

A.    the healthy brain theory, and contrast to the runaway brain theory by saying that the healthy brain theory suggests that large brains are simply better advertisements of how good our genes are compared to smaller brained apes.

B.    Because our brains produce behaviors such as art and language that we may be advertising our fitness to potential mates.

.                                 C.  Examples of other species that have developed behaviors as fitness indicators are songbirds, fruit flies and bowerbirds.  Songbirds repeat complicated melodious sings to reaveal their fitness.

 

IV.             Evolutionary Fitness and Physical Fitness

 

A.    Biologists believe that fitness is a means of surviving and reproducing. Evolutionary fitness has 3 important features: it is relative to competitors in a species, it is relative to an environment, and it is a statistical propensity rather than an achieved outcome.

 

B.    Fitness in the physical sense can also imply youth, health, athletic ability, and physical attractiveness.  Another contrast to evolutionary fitness is that physical fitness is closer to a measurable achievement than a statistical propensity.

 

C.    This theory of fitness indicators suggests that much of human courtship consists of advertising our physical fitness and mental fitness to sexual prospects. Physical fitness may mean body shape, facial features, skin condition, energy level, athleticism, fighting ability, and dancing ability

 

V.                MS. Fitness USA

A.    Sexual revolution of the last 20 years has come in the form of the Ms. Fitness USA pageant.

B.     The point was to show that Ms. Fitness USA contestants could only win if they trained like professional athletes by doing aerobics, weight lifting, stretching, sports and healthy eating.

 

VI.             Sexual Choice for Fitness

A.    The “lek paradox” is the most extreme case of a general problem with the heritability of fitness.  Any form of sexual selection for fitness indicators should even out genetic variation in fitness. 

B.    Fitness fluctuates according to changes in the environment and species adapt fairly quickly to those changes.  More importantly, however is the species interaction with surrounding parasites.

This arms race between parasites and hosts could maintain the incentive for mate choice. While this may explain why physical fitness and health remains heritable it does not explain why there is such variation in mental adaptations.

I.                  How Fitness Indicators Work

 

A.      Handicap Theory

1.   Sexual ornaments are handicaps that advertise true fitness by                                                                                                                                                                                                                                                                                                                                                                         handicapping an individual with survival costs.

2.    Because fitness indicators are handicaps, most sexual ornaments are not produced by all males to equal degree.

3.    The acts of love considered most romantic are often those that cost the giver the most, but that bring the smallest material benefits to the receiver.

B.      Effect on the Evolution of a Species

1.   The sexual selection also puts pressure on the trait to recruit a larger share of the individual’s energy budget for itself (130).”  In this way, sexual selection has turned an ordinary trait into a really good fitness indicator.

2.   This means that human mental abilities might be so complex because they are so efficient at advertising the brain’s mental abilities.

3.   “If a human mental trait shows large individual differences, high heritability, high condition-dependence, high costs, and high correlations with other mental and physical abilities, then it may have evolved through sexual selection as a fitness indictor (133).”

4.   Social norms or morality is developed to minimize the social costs of advertising one’s fitness.  “We value humility precisely because many people are unbearable braggarts who try to flaunt their fitness indicators so relentlessly that we cannot hold a decent conversation.  We value frugality because so many people embarrass everyone with their ostentatious displays of luxuries, and waste limited resources that others need.  We value egalitarianism because it protects the majority from aspiring despots intent on power and polygyny (136).”

 

II.               The Senses and Sexual Selection

 

A.      Sensory Bias Theory

1.   “The mind could be viewed as an entertainment system that appeals to the psychological preferences of other minds (138).” 

2.   The senses have multiple functions therefore they cannot be perfectly adapted to mate choice.  For example because primates eat fruit they have developed visual systems attracted to bright colors.  If a male primate happens to evolve a bright red face, he might prove more attractive to females.  The female senses are biased to notice bright colors and this influence is coined “sensory bias.” 

3.   “The senses used for mate choice in each species tend to be well matched to the sexual ornaments displayed by that species (142).” 

4.   Sexual ornaments may be so unpredictably diverse in different species because a new sexual ornament may excite the senses in a way that could never have been predicted.

5.   “Sensory bias theory reminds us that mate choice is mediated by perceptual abilities, and that as new perceptual abilities evolve, the way is opened for new kinds of sexual ornaments to evolve.  With the evolution of bird ears came the possibility of bird song (148).”

 

 

B.      Methods of Mitigating Sexual Choice

1.   The cold chooser

a.      The cold chooser compares prospective mates through a mathematical procedure and simply chooses the better.  No pleasure is derived from doing this. 

b.      It is suspected that most insects work like this. 

2.   The hot chooser

a.      The hot chooser chooses a mate by the way in which that individual gives them subjective feelings of pleasure. 

b.      A pleasure meter like this would be useful in telling an individual to do more of what gives them pleasure. 

c.       “Pleasure-giving courtship behavior is probably a better fitness indictor than courtship that merely activates sensations (152).”

 

 

 

 

I.                  The Ornamental Mind

A.    Entertainment industry

i.                   the mind has to stimulate various minds not knowing the exact way that will work best to accomplish a mating bond between the two.

ii.                 The mind reflects popular taste in order to appeal to others in their species.

iii.              Does NOT work like Darwin’s “survival of the fittest”. It does not focus on who can survive, instead, it focuses on how it can attract the others in it’s species.

B.    The Space of All Possible Stimulation

i.                   The fickle brain

a.     responds to some positively and some negatively.

b.     Cannot predict the brain and it’s preferences

ii.                 Mutual choice

a.     Mutual pleasure will be reached

b.     There will be no evolutionary changes to be seen as a result of this.

 

II.               Putting the Pieces Together

A.    Ornamental Mind theory has to join with the Fitness Indicator theory

i.                   this explains why some sexual ornaments stick around for generations

B.    There are similarities in the runaway theory, the indicator theory, and the sensory bias theory.

C.    The ornaments and the indicators interact

i.                   Indicators indicate quantity

ii.                 Ornaments vary the the design elements of the indicator

III.           Sexual Selection, Natural Selection, and Innovations

A.    They all intertwine

i.                   Sexual selection interacts with natural selection

ii.                 Natural selection combined with sexual selection, results in innovations

B.    The struggle of innovations

i.                   Innovations have a threshold that they should reach before gaining the trust of natural selection that they will be profitable

ii.                 The most trusted way is a gradual procedure

IV.             Sexual Selection and Venture Capital

A.    Species have no true form of venture capital

i. no security system that will guarantee their safety from extinction.

B.    Sexual selection is the closest thing to a form of venture capital.

 

V.                Innovations Through Sexual Choice

A.    Those benefits of the sexual selection are also capable of becoming beneficial to survival.

i.                   ex. Feathered wings of a bird have become beneficial to the sexual ornaments of the bird and have also become beneficial to the survival of the bird.

VI.             From a Production Orientation to a Marketing Orientation

A. Marketing is much more appealing and the ornaments attract more mates.

 

 

 

 

 

 

3.   Critical Review

a.     Interesting points

1.      Social norms or morality is developed to minimize the social costs of advertising one’s fitness.  “We value humility precisely because many people are unbearable braggarts who try to flaunt their fitness indicators so relentlessly that we cannot hold a decent conversation.  We value frugality because so many people embarrass everyone with their ostentatious displays of luxuries, and waste limited resources that others need.  We value egalitarianism because it protects the majority from aspiring despots intent on power and polygyny (136).”  Our moral values may in fact just be adaptations.

2.      Complex human mental abilities like art, music, and even consciousness may in fact be products of sexual selection used primarily as fitness indicators. 

3.      Our minds are like a business and like all good business’s we are market oriented.  Our minds evolved through a million years of market research called sexual selection.  We are walking, talking advertisements for our genes.

 

B.     Weak or Confusing points

 

  1. The Run-Away Effect-  Although we believe that this was explained in a previous chapter it was not adequately explained in chapters 4 and 5 and was referenced to many times.  Therefore quite a few sections were difficult to understand especially at the end when Miller was tying all of the different theories and arguments together.
  2. In chapter 5 page 158 in the section entitled, “Putting the pieces Together” we were confused with how Miller combined the; Runaway theory, the indictor theory, and sensory bias theory to create one cohesive argument.

 

C.    Points that we had further questions about

 

  1. Condition-Dependence and how it relates to fitness indicators
  2. What is the Cambrian explosion?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(1,M)

 
 

 

 

 

 

 

 

 

 

(1,M)