Summary and Review of Dr. Tatiana's Sex Advice to All Creation: The Definitive

Guide to the Evolutionary Biology of Sex by Olivia Judson (2002)

 

 By Jennifer de Puzo, Kathryn Marshall and Maribel Pulido

 

Chapter 8 Summary: Hell Hath No Fury

 

Females of various species have evolved to fight each other. However, unlike males, they rarely fight, and when they do, they do not fight to kill each other. More often, these fights are more verbal than physical. Females also usually do not fight over males, but over more significant matters. For example, birds will fight over nests. These fights are to assure their genes get passed onto the next generation and are more over resources for their offspring, rather than over males to copulate with.

Females have evolved to resort to various manipulative strategies. One way females do this is by manipulating other females. For example, in some species of newts, the females will steal male sperm packets left for another female. Female African butterflies will often chase away any other females they see near their mate. Another way females are manipulative is that they will intervene during another couple while they are copulating or courting. For example, some toads need males to watch their eggs for them, so in order to steal another female’s mate; she will intervene in the mating process. An additional method females will use is to manipulate males to make him invest more in her and her offspring. One example of this is some male frogs must hold the eggs in his vocal sacs for a period of about 52 days. He must do this in order for his offspring to survive. But during this period, he is unable to sing to attract more females.

Females may also use preventative strategies to keep her mate with her and her offspring. She wants to get as much of an investment from him as possible. If her mate copulates with another female, he may leave her offspring to help raise the offspring of the second female. One way she tries to prevent her mate from courting another female is to intervene. For example, male burying beetles will stand on their heads to attract other females with a scent that comes from their abdomens. If he already has a mate, and she sees him doing this, she will knock him over so he cannot attract other females. Another example is female pied flycatchers that will interrupt her male if she sees him singing to another female. Another method females may use to prevent her mate from investing time in another female and her offspring is infanticide. If more than one female mates with the same male, they will often try to kill each other’s offspring. One species that is an example of this are house sparrows. If a male has more than one mate, he will only help the female whose eggs hatch first. So the second female will try to kill the first female’s eggs.

Females may also use a more passive strategy to keep her mate. A passive strategy that some females use is when her mate is trying to court another female, instead of getting angry, she may instead use the opportunity to copulate with him again. His courting and act will actually arouse her as if it is meant for her, instead of trying to stop him. One species that does this are starlings. However, if this doesn’t work, and she sees that another female is attracted to her mate, she will use more aggressive actions. For example, northern harriers will intimidate and possibly attack a rival female. Blue tits will knock their rivals out of the air. Starlings will sing at another female to scare her off or if she sees her mate looking at another nest hole, she will fill it up to make it look occupied.

Females will at times fight with other females over males. They have evolved to fight for three reasons. First, they will fight out of desperation if there is a lack of males. Second, they will fight out of aspiration. This is when females are choosy with who they mate with and they strive to mate with the superior males. Third, they will fight out of possessiveness. This is to keep her mate from taking a mistress, and to keep him from investing in another female’s offspring.

 

 

Chapter 9: Aphrodisiacs, Love Potions, and Other Recipes From Cupid’s Kitchen

 

 

            This chapter starts off with a question: can animals put a “spell” on other animals in order to have them fall in “love” with another animal. Though there are no real “spells” per se, there are forms in which animals can stop another animal from copulating with another animal. Women normally benefit from having one partner because if they have more that one, problems arise, such as male-male conflict. They can engage in physical violence, use “chemicals to disable his predecessor’s sperm, or he can even make is own sperm hard to remove.” These are ways that they try decrease the male competition for the females.

            Male-female conflict also exits. Males find ways to gain control of the women so that she will not have other males to copulate with. Males can “deliver drugs that switch off her sex drive-an invisible, chemical chastity belt. Or daub her with an “antiaphrodisiac,” a chemical that makes her stink, so that other makes will find her repulsive.”

            Male Australian field crickets, the common housefly, fruit fly, and garden snails all use sneaky strategies in making it difficult for other males to copulate with their “female.” Seminal fluid alters a female’s behavior. It can turn off a women’s sex drive, some males can make it difficult to remove in females, and in some cases it can induce aggression in women towards other males. Therefore, males have powerful effects on females.  The red deer’s roar is an example of an aphrodisiac. This type of aphrodisiac however, is beneficial to women and does not limit them like the sneaky strategies do. The roars from the stag’s cause female deer’s to come into heat sooner and it also increases the odds that they can get pregnant early in the season. Therefore, not all aphrodisiacs are harmful to females.

            Though there are some cases, like in the red deer, where aphrodisiacs are beneficial to females, they usually have terrible consequences. It is for that reason that females are fighting back. They are becoming more resistant to “local” males as opposed to “foreign” males. They explain how females are fighting back through two experiments. The first experiment reveals how males and females react to forced monogamy. The results suggest that in an environment where monogamy exits leads to males being less manipulative towards females and the females do not fight back because they have nothing to fight for. A second experiment took place where the female was not allowed to fight back. This revealed how males continued to evolve in a way where they would be dominating and manipulative towards the females. The conclusion that the author came to was that “males had, I’m afraid become super males, completely redrawing the battlefield. Females were much more likely to be seduced by these fellows, failing to reject their advances even when under the influence of a regular male’s sex peptide.” 

            Finding a “partner” to engage in copulation and to have offspring becomes a difficult task for certain species despite the fact that the super male characteristic exists. The most important thing to do it to find a way to fertilize the egg by having a sperm attach to it. Reproduction is the most important concept in any species: “a group of organisms that can interbreed.” It is through interbreeding that new species can form. A see urchin is an example of how certain species can create new species. Male see urchins produce different types of proteins that eggs have similarities for.  These proteins are producing different types at an incredible rapid rate and consequently, new species are being produced.

            The “battle of the sexes” is one reason why reproduction evolves so fast.  This statement can only be proven if “rapid evolution in a given male reproduction protein is fueling the rapid evolution of a given female reproductive protein, and vice versa.” However, it does turn out that male protein is evolving in response to the egg. This occurs by having the male’s protein repeat itself twenty-eight times. However, repetitions of a protein can also lead to genetic problems. Huntington’s disease is an example of how changes in the number of repeats can cause problems in humans. “ When a repeated unit is large, a mutation that occurs in one unit may spread gradually through the other units through a passive process known as concerted evolution.” Though repetition of some protein can cause problems, in some species the mutation is and advantage to those who can only recognize its rapid change.

            Homosexuality is common among species like the bonobos, penguins, and dolphins. Many people question their behaviors and motives. Some people think that it enables them to achieve and orgasm, as it is found to be true for the Asian monkeys, it serves as a social function, facilitates teamwork, it is an antisocial function, or it is an act of desperation. Homosexuality does not coincide with the evolutionary theory of reproducing to keep the genes going through the generations. However there are some homosexual species, such as in the gull, where reproduction is possible. What about the species in which reproduction is possible? What function does it serve if they cannot produce offspring?

            Homosexuality becomes difficult to explain only if it has a genetic component, is exclusive, or it makes up a significant proportion of the populations. Though the search for homosexual genes has not been conclusive it seems likely that sexual orientation among mammals will turn out to have some genetic basis. It has also been difficult for researchers to find if homosexuality is exclusive throughout a species life. They also find it difficult to measure if and how animals have been exclusively homosexual throughout their lives.

            The traditional explanation for homosexuality explains that genes can be maintained if homosexual individuals act to increase the reproductive success of their relations. However, “there is not evidence that homosexuality amounts to an indirect way of spreading genes; in species of birds and mammals where young animals help their parents raise the next brood.”  Current explanations for homosexuality believe that it evolved as a reproductive suppression however, not evidence can explains homosexual behavior. It has also been discussed that homosexuality could be maintained if the genes were favored by natural selection. This could happen by heterozygote advantage where an offspring would have two forms of one gene rather than one form of gene from each of the parents. Humans who have two copies of the same form are an average heterosexual, but sterile. If you were a person where you would have one form of each would mean that that person would be a highly fertile heterosexual.

Chapter 10 Summary: Till Death Do Us Part

 

            True monogamy is so rare that it is one of the most deviant behaviors in biology.  Before the 1980s, over 90 percent of bird species were believed to be monogamous at least for the duration of the breeding season, and many couples were thought to mate for life.  However, better genetic techniques and the spread of paternity testing proved this idea false.  If animals live in pairs, they are said to be socially monogamous, which is a term that does not make assumptions regarding their sex lives.

            Monogamy will evolve as a strategy for all members of a population only when it is in the best interest of both males and females.  This means that monogamy will last when the amount of surviving children of monogamous couples exceeds those of polygamous couples.  Since fidelity is rarely in the best interest of one of the parties, let alone both parties, it is a rarity.

            There are several theories of monogamy that are discussed in this chapter.  The first is the Good Wife Theory of Monogamy.  This essentially states that males’ opportunities to philander are lessened because females are obsessively faithful to her mate for fear of losing his help with the kids.  According to the Good Wife Theory of Monogamy, monogamy is a female plot forced on males. 

This theory is unlikely to apply because of three reasons.  First, the assumption that males would wander if they could and that being unfaithful is in his interest is often wrong because sexual fidelity can be in the male’s interest.  Second, monogamy can evolve even if the male does not help the female raise the children.  The third issue with the Good Wife Theory is that a female’s need for male help does not necessarily guarantee her fidelity.  For example, fat-tailed dwarf lemur male/female couples live together in pairs and the females cannot raise offspring on their own.  Still, genetic testing shows that infidelity is widespread and that males oftentimes help to raise children that are not theirs.  When fidelity and cooperation go together, monogamy is typically not the consequence as the Good Wife Theory states; rather monogamy is the cause of fidelity and cooperation. 

Other theories of monogamy are the Danger Theory of Monogamy and the Pop-‘Em-Out Theory of Monogamy.  If females are spread out then males might find that they are better off staying with a single female and keeping rivals away.  It might be risky to leave because finding another female would involve a dangerous or long journey.  There is a direct relationship between the risk and the incentive to remain.  The greater the risk to leave the female, then the greater the incentive is for the males to remain with their females.  This is the Danger Theory of Monogamy.  The Pop-‘Em-Out Theory of Monogamy deals with the time between a female’s breeding.  If the female breeds quickly, then there may be no point for a male to leave on a journey to find another female.  The Lysiosquilla sulcata are mantis shrimp that have strong circumstantial evidence for monogamy.   

If a female gains significantly from having a male around, then she may be less likely to throw him out.  For example, a male could help a female defend her territory or he could help her with childcare.        

The male Djungarian hamster is “such attentive as a father that he plays with midwife for the births of his pups (the only male mammal so far known to do this as a matter of routine), helping them to emerge from the birth canal, opening their airways so they can breathe and licking them clean…Consistent with the Pop-‘Em-Out Theory, female Djungarian hamsters live apart from one another: their ranges do not overlap.  And they are prolific breeders.  In a year they can produce eighteen litters of between one and nine pups each.  In contrast, their close relative the Siberian hamster breeds for only a few months of the year and exhibits neither paternal care nor monogamy” (156-7).

Monogamous organisms are often aggressive toward any animal that’s not their

partner.  It’s usually thought that they are aggressive because they are monogamous.  Sometimes they may be monogamous because they are aggressive.  If aggressive individuals toward members of their own sex have more surviving offspring than more amiable creatures, then monogamy may arise as a side effect of that aggression.  This is known as the Sociopath Theory of Monogamy. 

            Monogamy may arise when cheating or desertion by either partner results in total reproductive failure for both.  This is the Mutually Assured Destruction Theory of Monogamy or MAD.  Hornbills found in Africa and Asia is completely dependent on each other for the survival of the brood. 

            California mouse couples are truly monogamous, living together faithfully until one of the partners dies.  As stated earlier, a population can only evolve from promiscuity to monogamy if faithful couples consistently have more surviving children than the unfaithful.  “If this happens, and if monogamy has a genetic basis, then genes associated with monogamy will spread.  Eventually everyone in the population will have these genes” (160).  Scientists are starting to figure out the genetic basis of monogamy in the prairie mole. 

            “When a boy prairie vole meets a girl prairie vole and they decide to become an item, they consummate their relationship by copulating anywhere from fifteen to thirty times in a twenty-four hours.  From this point on, the lovers grow greatly attached, endlessly cuddling and grooming each other, the picture of mushy affection…. Before losing his virginity, a male is a peaceful sort of chaps…after his first night of passion his personality changes.  How if he sees any prairie vole- male or female- who is not his partner, he’ll attack vigorously.  For a male prairie vole, the sex act causes the release of vasopressin, a hormone that bins to special receptors (160).”

            Since monogamy has evolved independently in different species, the mechanisms may well differ from one monogamous species to the next.  If sex also turns out to have potent hormonal effects in other monogamous species, this would explain why many of them regularly engage in sex that, owing to its timing, cannot possibly result in reproduction.  It is important to remember that understanding the genetic mechanisms of monogamy is quite separate from understanding why organisms have evolved to be monogamous in the first place. 

            Humans cannot be described as exclusively monogamous.  Some individuals are faithful to one partner for their whole wives; few have or admit to having thousands of sex partners.  In monogamous species, males and females tend to be roughly the same size; in species where a few big males hold harems, males tend to be enormously bigger than females.  Human males tend to be only slightly larger than females.  In the gorilla, adult males are typically twice the weight of adult females.

            In respect to physical difference between human males and other male apes, testicle size is usually associated with the risk of sperm competition.  “Males that are at low risk of sperm competition generally have testicles that are small in relation to their body size.  Males that are at high risk of sperm competition generally have enormous testicles in relation to their body size.  Male gorillas are at a low risk of sperm competition and have tiny testicles.  Male chimpanzees are at high risk of sperm competition and have gigantic testicles.  In comparison, human males have medium-sized testicles, suggesting a low to moderate risk of sperm competition” (163).

            The rate of infidelity as measured by genetic paternity testing is rumored to be extremely high among humans-30 percent or more.  These results need to be treated with more caution in humans than in other species: contraception and abortion enable humans to avoid having a child during an extramarital affair.

            “For most boys and girls, wedding rings are made of fool’s gold- real, true love is precious and rare, the confluence of bizarre biological forces.  Several factors may contribute to monogamy, but you’ll find that true love works best when it is absolutely MAD” (165). 

           

           

 

  

 

 

 

Chapter 8 Outline

 

 

I.                    Females of various species fight, just like the males do.

A.      Rarely do females fight, and when they do, they do not fight to kill each other

B.      Mainly will fight when males are in short supply

C.      Females will often resort to various manipulative actions

1.      Females may manipulate other females

2.      Females may, for example, intervene during copulation

3.      Females may manipulate males by making them invest more time into her and her offspring

D.     Females may also take preventative actions to keep her mate

1.      Females may intervene in her mate courting another female

2.      Females may prevent her mate from investing time in another female and her offspring

a)       Infanticide

E.       Females may use a more passive strategy to keep her mate

1.      For example, when her mate is trying to court another female, instead of getting angry, she may instead use the opportunity to copulate with him again

II.                 Females have evolved to fight over males for these reasons

A.                 Desperation -lack of males

B.                 Aspiration - she chooses to mate with superior males

C.                 Possessiveness - to keep her mate from taking a mistress

 

 

 

 

 

 

 

Chapter 9 Outline

 

I.        Aphrodisiacs and love potions

A.     Love Spells

1.      Male-male conflict

a)      Physical aggression

b)      “Sneaky strategies”

2.      Male-female conflict

a)      Male decreasing female’s sex drive

b)      “Antiaphrodisiac”

B.     Aphrodisiacs

1.      Seminal Fluid

a)      Alter female behavior

b)      Can be beneficial in some species

2.      Females are fighting against the males sneaky strategies

a)      Less susceptible to monogamy with hometown species

b)      Two experiments where females are fighting back

II.     Finding a partner for copulation

A.     Fertilization

B.     Definition of species

1.      New species emerging

2.      Rapidly evolving protein

3.      Effects of a repeated protein

a)      Mutations

b)      Advantages of mutations

III.   Homosexuality

A.     Homosexual species

1.      Why are they homosexual?

a)      Reasons for homosexuality

b)      Three conditions of homosexuality

2.      Heterozyogte advantage

a)      Fertile humans

b)      Genetic homosexuality

 

 

 

 

 

 

 

 

 

 

 

 

 

Chapter 10 Outline

 

I.          Monogamy

A.     Monogamy will evolve as a strategy for all members of a population only when it is in the best interest of both males and females

B.     Monogamy will last when the amount of surviving children of monogamous couples exceeds those of polygamous couples

III.               Theories of Monogamy

A.     Good Wife Theory of Monogamy

1.       Males’ opportunities to philander are lessened

2.       Females obsessively faithful so mate can help raise offspring

3.       Unlikely to apply for three reasons

a)      The assumption that males would wander if they could and that being unfaithful is in his interest is often wrong because sexual fidelity can be in the male’s interest

b)      Monogamy can occur even if male does not help raise children

c)      Female’s need for male help does not guarantee her fidelity

B.      Danger Theory of Monogamy

1.      Males might find that they are better off staying with a single female and keeping rivals away

2.      Might be risky to leave because finding another female would involve a dangerous or long journey

C.     Pop-‘Em-Out Theory of Monogamy

1.      Deals with the time between a female’s breeding

2.      If the female breeds quickly, then there may be no point for a male to leave on a journey to find another female

D.      Sociopath Theory of Monogamy

1.      Monogamous organisms often aggressive toward any animal that is not their partner

2.      Usually thought that they are aggressive because they are monogamous

3.      If aggressive individuals have more surviving offspring than more amiable creatures, then monogamy may arise as a side effect of that aggression

E.       Mutually Assured Destruction Theory of Monogamy (“MAD”)

1.      Cheating or desertion by either partner results in total reproductive failure for both

III.       Physical Characteristics Related to Monogamy

A.      In monogamous species, males and females tend to be roughly the same size

B.      Human males tend to be only slightly larger than females

C.      Testicle size usually associated with the risk of sperm competition

a.       Males at low risk of sperm competition generally have small testicles

b.      Males at high risk of sperm competition generally have large testicles

c.       Human males have medium-sized testicles, suggesting a low to moderate risk of sperm competition

 

Chapter 8 Critical Review Items:

 

(a)     The main point in Chapter 8 is that females will often take preventative measures in order to keep her mate with her to get the most investment out of him that she can. For example, she may fight off other females to keep the females away from her mate, or she may prevent him from flirting with other females. An interesting point is that at times, instead of being angry with her mate for courting other females, she will take the opportunity to copulate with him again.

(b)    One weakness of this chapter was the organization of it. It did not seem to be organized at all. Instead it jumped from topic to topic and mixed topics together.

 

Chapter 9 Critical Review Items:

 

(a) There are some homosexual species that can in fact have offspring, usually females.

(b)   The chapter needs more clarification and explanation on the heterozygote advantage.

 

Chapter 10 Critical Review Items:

 

(a) An interesting point in Chapter 10 is the Danger Theory of Monogamy.  If females are spread out then males might find that they are better off staying with a single female and keeping rivals away.  It might be risky to leave because finding another female would involve a dangerous or long journey.  There is a direct relationship between the risk and the incentive to remain. 

(b) This chapter is not direct enough and is extremely confusing and hard to follow.

 

 

 

 

 

 

 

 

 

 

 

 

Ch. 8 Outline:

 

I.                    Females of various species fight, just like the males do.

A.                 Rarely do females fight, and when they do, they do not fight to kill each other.

B.                 Mainly will fight when males are in short supply.

C.                 Females will often resort to various manipulative actions.

4.      Females may manipulate other females.

5.      Females may, for example, intervene during copulation.

6.      Females may manipulate males by making them invest more time into her and her offspring.

D.                 Females may also take preventative actions to keep her mate.

1.      Females may intervene in her mate courting another female.

2.      Females may prevent her mate from investing time in another female and her offspring. For example, infanticide.

E.                  Females may use a more passive strategy to keep her mate.

1.      For example, when her mate is trying to court another female, instead of getting angry, she may instead use the opportunity to copulate with him again.

II.                 Females have evolved to fight over males for these reasons:

D.                 Desperation. When there is a lack of males.

E.                  Aspiration. When she chooses to mate with superior males.

F.                  Possessiveness. To keep her mate from taking a mistress.

 

 

  

Ch. 8 Critical Review Items:

 

(c)     The main point in Chapter 8 is that females will often take preventative measures in order to keep her mate with her to get the most investment out of him that she can. For example, she may fight off other females to keep the females away from her mate, or she may prevent him from flirting with other females. An interesting point is that at times, instead of being angry with her mate for courting other females, she will take the opportunity to copulate with him again.

(d)    One weakness of this chapter was the organization of it. It did not seem to be organized at all. Instead t jumped from topic to topic and mixed topics together.

 

 

Ch. 8 Summary:

 

Females of various species have evolved to fight each other. However, unlike males, they rarely fight, and when they do, they do not fight to kill each other. More often, these fights are more verbal than physical. Females also usually do not fight over males, but over more significant matters. For example, birds will fight over nests. These fights are to assure their genes get passed onto the next generation and are more over resources for their offspring, rather than over males to copulate with.

Females have evolved to resort to various manipulative strategies. One way females do this is by manipulating other females. For example, in some species of newts, the females will steal male sperm packets left for another female. Female African butterflies will often chase away any other females they see near their mate. Another way females are manipulative is that they will intervene during another couple while they are copulating or courting. For example, some toads need males to watch their eggs for them, so in order to steal another female’s mate, she will intervene in the mating process. An additional method females will use is to manipulate males to make him invest more in her and her offspring. One example of this is some male frogs must hold the eggs in his vocal sacs for a period of about 52 days. He must do this in order for his offspring to survive. But during this period, he is unable to sing to attract more females.

Females may also use preventative strategies to keep her mate with her and her offspring. She wants to get as much of an investment from him as possible. If her mate copulates with another female, he may leave her offspring to help raise the offspring of the second female. One way she tries to prevent her mate from courting another female is to intervene. For example, male burying beetles will stand on their heads to attract other females with a scent that comes from their abdomens. If he already has a mate, and she sees him doing this, she will knock him over so he cannot attract other females. Another example is female pied flycatchers who will interrupt her male if she sees him singing to another female. Another method females may use to prevent her mate from investing time in another female and her offspring is infanticide. If more than one female mates with the same male, they will often try to kill each others’ offspring. One species that is an example of this are house sparrows. If a male has more than one mate, he will only help the female whose eggs hatch first. So the second female will try to kill the first female’s eggs.

Females may also use a more passive strategy to keep her mate. A passive strategy some females use is when her mate is trying to court another female, instead of getting angry, she may instead use the opportunity to copulate with him again. She will actually become aroused by his courting and act as if it is meant for her, instead of trying to stop him. One species that does this are starlings. However, if this doesn’t work, and she sees that another female is attracted to her mate, she will use more aggressive actions. For example, northern harriers will intimidate and possibly attack a rival female. Blue tits will knock their rivals out of the air. Starlings will sing at another female to scare her off or if she sees her mate looking at another nest hole, she will fill it up to make it look occupied.

Females will at times fight with other females over males. They have evolved to fight for three reasons. First, they will fight out of desperation if there is a lack of males. Second, they will fight out of aspiration. This is when females are choosy with who they mate with and they strive to mate with the superior males. Third, they will fight out of possessiveness. This is to keep her mate from taking a mistress, and to keep him from investing in another female’s offspring.