The following is authorized by the publishing house and excerpted from "Their Sex", written by Wang Dake, New Classic Culture | Nova Press, July 2022. The pictures in this article are all from "Their Sex".
Pervasive eavesdroppers
Some real signals are interspersed with lies, and some real signals want to hide themselves. A qualified researcher must not only learn to find the signal of honesty in the phenomena of virtual reality, but also be able to dig three feet into the ground and find the truth that the creature does not want us to know. Only humans worry about their call recordings, historical messages, and purchase records being stolen? Of course not. The issue of information security has long plagued all honest and trustworthy creatures. After all, it is biological needs to communicate, communication must transmit information, in the process of transmission, information may be stolen and deciphered. Some people make a fortune by eavesdropping and peeking, and their children and grandchildren are full of halls, and some people rely on eavesdropping and peeking to kill people invisibly. Eavesdroppers are pervasive, and once the information is transmitted, who receives it is out of the control of the sender.
The phenomenon of eavesdropping in the biological world is far more common than you can imagine, and even some plants will eavesdrop.
The experimenters found that the tobacco plant could decipher the conversation between its neighbors, the mountain wormwood tree. When mugwort trees suffer physical damage, especially when plant-eating animals bite them, they emit damaged pheromones. This pheromone travels through the air, and the neighbor tobacco of the mountain wormwood tree can steal this signal and strengthen self-protection. The experimenters cut off the branches of the mugwort tree to simulate the mugwort tree being chewed, and the tobacco immediately produced more defensive elements in the leaves. In fact, insect infestations do not occur, and tobacco whites consume more energy in the defense system, making them more vulnerable to frost in the winter. The eavesdroppers in this experiment only increased their self-defense and did not harm the mountain wormwood tree, but in nature, there are more wiretapping behaviors that directly harm the interests of the eavesdroppers.
Bats can emit ultrasonic waves to locate prey. Many animals don't have the ability to receive ultrasound, so bats don't have to worry too much about eavesdropping on their prey. However, intraspecific competition for the same species is often the most intense, because everyone loves the same things, loves the same house, and has the same need for a spouse. In order to survive, bats extended their black hands to their compatriots. Where there are compatriots, there is meat to eat. Bats have found that if their kind gather in a certain place, they are either eating, sleeping, or mating. It's sometimes easier to grab a sibling than to hunt for yourself, so some lone bats approach and join other bat colonies by eavesdropping on sonar signals. It is also for this reason that bats with fixed shelter pay more attention to information security than wandering bat species to prevent being deciphered by similar types.
Male bubble toads have colorful laryngeal sacs that store gas and help them make noisy courtship calls. Between the diastolic laryngeal sacs, ripples are created on the surface of the water, and the water streaks can also attract females. However, the lip bat sees through this trick and will look for water waves to find the male bubble toad. There are countless male animals that die to mate, and living and mating are two conflicting life activities. Despite the grim situation, the male animals are still facing the difficulties, and perhaps, from another point of view, the males may live to court. There are three main directions to reproductive information theft.
First, females eavesdrop, peek at females, and follow the trend of choosing a mate. For young females who have no experience in finding husbands, they often peek at what kind of males the experienced females (such as older females) choose, and then follow behind to mate with the male.
Second, females eavesdrop and peek at males. The young female grows up and soon discovers that it is not always right to listen to her mother, but to judge with her own head. The simplest and most accurate judgment is who has the higher force value. While violence does not create wealth, without violence, the wealth created could be robbed. Females can peek at two males fighting and have accurate mate quality information while fully preserving themselves.
Third, males eavesdrop and peek at males. In the process of competing for a spouse, male fights are very common, but the cost of fighting is too high, and if you are not careful, you will hang up. From the beginning of the fight to the end of the fight, the victory and defeat will gradually become clear, and the sooner the loser concedes defeat, the less damage he will suffer. Experienced males don't even need to start a fight to know if the opponent's strength is above their own. If so, shake hands and make peace, give up the female, and go find a new battlefield for yourself. Young males always think they will win, fight without measure, and finally fold the battlefield. And peeking at other male fights can know the strength of the other party at no cost, if the other party is strong, then go to the top, if the other party is weak, it will be a move to defeat the enemy. Only by seeing more can we better understand ourselves.
Why isn't there a fourth point, the male eavesdropping on the female? Because the male saw the female and immediately pursued it, he could not bear to eavesdrop.
The pictures in this article are from "Their Sex".
Follow the trend and choose a mate
What is mate selection? It is not to "rationally" judge whether the quality of the opposite sex is good or not, but to not think about it, and everyone is in the clouds. If you see the opposite sex and others mating, it means that it is of good quality, so other people of the same sex have to mate with it. Then I should mate with it too. Following the trend of choosing a couple has a certain adaptive significance, usually when you don't know how to choose but have to make a choice, instead of blindly choosing, it is better to learn from other people's choices. What if someone else's choice is deliberate? Imagine that we eat in a strange place, and the knowledge of choosing a restaurant is great, but the simplest and most commonly used method is to see which family is more. We tend to think that a place that needs to queue up for an hour to eat must be good and cheap. The same is true of choosing a spouse. Females tend to think that other females are not fools, and choosing this male shows that he must have something superior, and he can't go wrong with them. However, following the trend to make decisions will inevitably overturn, just like they can't do the problem, so they casually copied a person's volume, and found that the other party will not actually do this problem.
By artificially manipulating the opposite sex of the males, the researchers caused the females to develop significantly different preferences for two similar groups of males. The experimenters placed two peacock fish of similar length and color in two single rooms separated by a transparent aquarium, and then let a female act as a "childcare" near one of the single rooms, pretending to be attracted to the male. The male pursues her passionately, and she dances with the male. Another experimental female peered through the glass and witnessed everything the fish had sex with, creating inexplicably subtle emotions for the male. The childcare was then removed and the experimental females were free to choose one of the two males to mate, and 17 of the 20 experiments the female chose the newly mated male. In order to eliminate interference, for example, some males may be naturally more favored by the opposite sex, the experimenters let the childcare child play a play with another male, resulting in similar results.
Female preference for males may be influenced by other females, and may change course even if they already have a favorite object. Place the two male peacock fish in the aquarium and let the experimental female freely choose a mate. After the selection, the researchers with bad stomachs separated the couple in love and put a childcare child next to the male who had not just been selected. The experimental female watched silently from the sidelines, and she suspected that she had just chosen the wrong mate, and perhaps now this was with someone else to qingqing me and my male quality was higher. The experimenter removed the childcare, giving the experimental females one last chance to choose a partner. Sure enough, love did not stand the test, and the proportion of heart changes in the experimental females was significantly higher than that of the control experiment. To avoid the effects of the female's interest in her mates decreasing with the number of matings (i.e., the "Coolidge effect") of the new and the old, the control experiment repeated the preferences of the experimental female without childcare and found that she still liked the males she had first looked at.
Younger females mimic the choices of older females, and vice versa. The experimenters refined the first experiment described in this section and found that when childcare was an older female and the subject was a young female, the younger female mimicked the selection of the older female. But when childcare is a young female and the subject is an older female, the older female is not confused, and the selection results are not significantly different from the control experiment (that is, free selection without childcare). This may be because only younger individuals often learn from older individuals.
Peep into the fragrant scene
While watching mating scenes may not get much useful information, creatures have an endless interest in watching glamorous scenes. On the one hand, viewing itself may bring sexual stimulation, providing another pathway to sexual pleasure for males who have little sexual experience. On the other hand, some mating skills can also be learned from watching.
When I was doing experiments, I found that once there was a chicken in a coop mating, the roosters in the three side coops around would squeeze their heads to watch. Those who eat, drink, fight, and sleep all lay down their work, gathered in front of the wire cage, and even fought hard to seize the best observation position. To protect the privacy of the experimental chickens, I wrapped a dark green net around the three sides of the cage to cover the eyes of the roosters who liked to watch the mating scene. However, there were roosters that actually shrunk out of the gap under the net, sandwiched between the net and the wire, watching with relish, some roosters flying to the branches a little farther away, looking at their necks, and others standing on their knees and watching.
I thought it was just the rooster's bad taste, but what I didn't expect was that the hen was also keen on it. The hen would peck at the edge of the net, then tuck her little head in and watch intently with one eye on her side. You know, the vast majority of mating is compulsive behavior, and hens usually hate mating happening to themselves, and often avoid roosters, but why are they so excited about watching other chickens mate?
Animals that love to peek are not only chickens. Evolutionary biology tends to give a plausible explanation for all animal behavior: voyeurism, for learning. The simplest example is that the unsophisticated panda learns the skills of "snapping" by watching "Panda A film". If the chickens in one coop are mating, the roosters in the three side coops around them will squeeze their heads to watch.
A chicken who is keen to peek into the fragrant scene.
Young animals don't rely on voyeurism on their elders, how do you think they learn to pass on their generations? The news has reported that the giant panda refused to mate during the estrus period and was first loved after watching the "Panda A film".
Still, scholars can't explain why experienced animals are still keen to voyeuristically. They came up with many hypotheses, but none of them could be fully confirmed. Studies have found that perhaps for male voyeurs, watching others "snap" can get accurate information about whether the female is in the ovulation period.
Our not-so-close relative, the Mediterranean macaque, used to bark during mating. So, the researchers had the hypothesis that the female shouted during mating to indicate that she was ovulating. However, by measuring female hormone levels, they found no relationship between the two, but by analyzing the frequency and spacing of female calls, they found that this was related to whether the male ejaculated or not. After the male ejaculates, the female's call is different, if the female's call does not change, this may give other males in the group a signal, that is, although the female mated, but the male did not ejaculate, so the risk of sperm competition is small, other males if intentional, but can pursue a bit. However, because the researchers could not manipulate the female's call or the male's ejaculation, it was impossible to determine whether the different calls of the females caused the difference in male ejaculation, or whether the male ejaculation caused the change in the female's voice.
Another study also found a link between calls and ejaculation. The researchers remotely judged whether males had ejaculated by observing their body movements and linked ejaculation to the females' cries. They found that if the female didn't bark, then the male had only a 1.8 percent chance of ejaculation; If the female barks, the probability of male ejaculation is as high as 59%. The researchers have proposed two hypotheses in this regard. The first hypothesis is that the female is called to the mate, and after the call the spouse is more likely to ejaculate, thus achieving the ultimate goal of mating. However, existing experiments can only confirm the correlation between the two, but cannot confirm the cause and effect. The second hypothesis is that in a world without privacy, females are called to males who are watching. Multiple experiments have shown that the female's cry can indeed stimulate the sexual desire of males.
The experimenters recorded the female monkeys' calls, and then randomly divided the females into two groups, one set of background music is the call, and the other group of background music is murmur. Observations have found that females in the call group have relationships with more numerous males, and the mating intervals are also shorter. By mating with multiple males over a short period of time, females are able to trigger sperm competition, helping to screen for higher quality sperm.
However, why can't the males who are watching control their eyes and ears, but want to be used?
The answer seems to be that this is a two-way process of utilization. Males will adjust their mating strategies based on the female's mating history, and the more information they have, the more accurate their judgments will be. Usually, if the female may have mated, the male must increase the amount of ejaculation in order to increase the probability of successful fertilization. But if the female has already accepted a lot of male sperm, then her wishful thinking to increase the amount of ejaculation may not achieve the desired effect, then the male will cut a lot.
So, what can the females who are watching get from the fragrant scene?
Why voyeurism?
Perhaps for females, peeping at someone else's mating can tell if the male is of good quality. Some males are in poor health and are unable to complete the mating process, and female voyeurs can exclude him. Some males are very cruel to females, and female voyeurs can stay away from him. If the female takes the initiative to court the male, then the male is likely to have a skill and can be considered.
Although there are some physiological factors for good males to spy on others mating, it is also important to know themselves by comparing themselves with others. Why can't someone else find an object? What can I learn from him? When I meet in the future, should I fight or flee?
In the experimental scenario described in the previous section, the fragrant scene of both the rooster and the hen competing to watch the mating is an example. However, under natural conditions, the rooster will not actually spy on other chickens mating, but directly rush up to break up the couple, take the opportunity to mate with the female, if beaten, quickly escape. Because the male who is peeping chases away the intruder and then warms up with the female, it is most likely that he will not catch up and fight.
In more cases, both sides of the sexual selection prefer a voyeuristic scene, where two males fight.
This is the case with male fish. Knowing who is strong and who is weak can be more accurate in bullying. The key to forming a society lies in the definition of classes, so that there are fewer contradictions in the distribution of resources. A big embodiment of social skills is to find the right position and do what should be done in this position. The more you eavesdrop, the more accurate your judgment of yourself is.
This voyeurism is not limited to "advanced" vertebrates, and scientists have found that The Protocrayfish Canker's Candela can also extract information useful to itself from its disturbed environment.
Under normal circumstances, female crayfish can not see the quality of male crayfish at a glance, it is simply to close their eyes and choose their husbands. However, if they are given the opportunity to spy on two males fighting, they will most likely choose the winning side. The same thing happens in fish.
Jousting is a good way for many creatures to choose a husband, and some females will even deliberately provoke two males to duel for love. At first glance, this strategy is unprofitable. If one male defeats the other, the female picks out the good genes, and if both sides are killed, the female leaves to find the next object.
However, the female's manipulation of the male is not always the way it should be. If two males join forces, the female suffers. There are also some males who, once they see the female next to them, even ignore the fight, and run upside down to show kindness, and the female will not get the desired result.
Violence is the final step in confrontation. If possible, males will take a gentler approach, such as fighting songs. Male mainly attract their spouses by singing, and the rules of the singing competition are that two males sing and the voice can overshadow each other's victory.
The researchers divided a family of birds in a forest into two groups, and they recorded a group of males, and the sound of the recording always overshadowed the male, showing that the recording was the winner and the male was the loser. The other group is just the opposite, as soon as the male sings, the recording is cassette, and the recording only dares to sing two sentences during the male's short break, showing that the recording is the loser and the male is the winner.
In fact, there is no difference in the quality of the singing of the two males, and the effect is all artificial manipulation. Male spouses peeked into all this, and then the evil researchers began to analyze the probability of their spouses cheating, and found with great joy that it was easier for spouses who thought their husbands were losers to cheat, and their main cheating targets were winning male neighbors.
Without contrast, there is no harm.
Some animals are found by voyeurs and will also counter-reconnoiter. In one experiment, the male had two females to choose from at the same time, and he always preferred one of them. Then, the experimenter put in another male fish as the audience, but the original male fish swam more to the female fish he did not like, doing the wrong inducement.
In order to confuse the enemy, he pretends to flirt with the female he does not like, preventing the opponent from seeing who he really likes, so as to darken the chen cang and divert the firepower. Just like finding someone copying your test paper, some experiments further point out that the more potential voyeurs nearby, the easier it is for males to give false signals, and the anti-reconnaissance ability seems to be related to personality, and bold males will deceive people.
This is not only a wiretapping storm, it is simply a showbiz storm.
Text/Wang Dake
Excerpt/Li Yongbo
Introduction Proofreading/Lucy