Mrs. Darth Vader
05-14-2010, 06:21
Sagan starts chapter 12 by telling one of the Greek myths. He used this particular myth to illustrate that the Greeks understood that substance that makes one male needs to be the “right” or “correct” amount. Too much causes trouble with arrogance. Too little causes weakness. Sagan then gets into the hard science. An experiment done on sparrows showed that it is the testosterone that gives the males their aggressiveness, their territoriality, dominance and sex drive. When they were castrated the same sparrows that were aggressive became submissive. They lost there desire to guard their territory from strangers and had no interest in sex. Interesting note too much testosterone can also lead to low sex drive for procreative purposes but only used for aggression and dominance but that is discussed later in this book. When injected with a certain steroid molecule (testosterone) suddenly all their traditional male traits returned.
Sagan then describes how testosterone effects the brain. In the brain there are receptor sites which chemically bind with testosterone. In the brain the testosterone centers are responsible for such behaviors as strutting, bullying, fighting, copulating, defending territory and fitting into a dominance hierarchy and or running it. If an animal has a high testosterone level he will want to dominate a large territory. He will dominate the whole territory including the other species who live in that territory. Animals such as mice do not see the connection between conception and the birth of the next generation of mice. Here the DNA is in control. The DNA gives the mice it’s sex drive so more mice can be made. Sagan describes what lengths mice will go just to have sex and just how much power the DNA have in controlling a species and continuing that species.
Sagan then goes from testosterone to estrogen. Estrogen is the opposite of testosterone because it curbs aggressiveness in females. Estrogen is calming. Progesterone increases the desire to protect and care for the young. These hormones are responsible for the feminine temperament. Here it should be noted that females have testosterone but just in small amounts. Occasionally a female can have too much testosterone and be aggressive and dominating like their male counter parts. Sagan then describes experiments where estrogen is given to both males and females. In both cases dominance and aggression is lowered. When testosterone is added to both males and females both become dominating and aggressive. Then Sagan sights an instance where there is a point when too much testosterone causes sterility. There is a hidden limit in nature where too much testosterone causes atrophy of the testicles. Nature has a turn off valve.
Sagan tells a story about an experiment on sparrows. Here this experiment shows how tension, anxiety and aggression creates the production of testosterone. Sagan sights the example of how sparrows normally establish their territories. Things are calm when a territory is well established but remove one of the sparrows from it’s territory and the tension automatically shoots up in neighboring areas because someone now has to fill the void or vacancy. Sparrows that had once lost in fights rise up to the challenge. Neighboring victors get more aggressive to protect their turf. The bloodstream of the sparrows are now filled with testosterone. Now all the sparrows are more aggressive. The same is true for most animals including humans. From here one could easily ask the question; Is American testosterone in both males and females higher than in a country like the former Soviet Union where anxiety is kept to a minimum and the struggle for existence is removed by their socialistic system?
The subject then switched to male ritual combat where the looser has a marked drop in testosterone. This seems to be true in animals ranging from pit vipers to primates. Sagan then talks about why even some plant eating animals guard their territory. He gives the example of birds that take nectar from flowers. In the morning when the nectar supply is plentiful it seems the birds do not guard their territory and allow stranger birds to partake. But by noon when the supply is dwindling they chase the strangers away. Scarcity makes one vicious and aggressively guard your territory. Fear has a smell. So if you are a mouse that is suddenly caused to fear all the other mice will run away from you. The predator will go for you because you are afraid.
Sagan then gets into how animals sound the alarm when a predator is near. The noise for a ground predator is different than the noise for a predator in the air. In lab tests on cockerels the female sounds the alarm only 13% of the time. Castrated cockerels were the least likely to sound the alarm. Regular cockerel males sounded the alarm most of the time. So it looks like testosterone also plays a role in a cockerel’s willingness to sound the alarm. If the bird were alone it just freezes and makes no sound. Warnings are only given if others of it’s species are present.
There is another molecule responsible for a peaceful demeanor. This molecule in the brain lessons aggression. More aggressive rats have less of this chemical in the brain. If a group of rats are very aggressive and killing one another is seen as common place, the other rats respond by becoming more aggressive and also kill. The threat spreads through out the community.
Sagan describes another experiment where there were pairs of rats that had to do a cooperative action in order to get the food. There were female pairs, normal male pairs, castrated male pairs, and male rats who lived alone until the experiment, female rat pairs that lived alone until the experiment and high testosterone males. The results were as fallows. Female and male castrates learned fairly quickly. Normal males and male castrates that got testosterone administered learned far more slowly. Normal male solitaries learned the slowest. The solitary males that were jolted with extra testosterone and males with high testosterone levels never learned at all. Females who lived alone, until the experiment, learned to do the experiment as well. The high testosterone males never learned because they could not cooperate and preferred violent combat instead of cooperating. The scientists concluded that “testosterone makes you stupid.” Page 237 “Shadows Of Forgotten Ancestors” by Carl Sagan. There are many experiments done with rats where the male chose a jolt of testosterone over food or fighting another rat which also gives a jolt in testosterone. Here we are reminded to wonder about humans both males and females. There are people that seem to enjoy and purposely cause fights. Could it be they are craving a testosterone jolt? It seems that testosterone has the quality of a drug because when you fill your bloodstream with testosterone you feel stronger, invincible and more brave. These facts in the lab on rats does make one naturally think of the human in your life that plays the role of the dominator even if the person is female. This desire to dominate and control is clearly the result of too much testosterone.
Sagan ends this chapter in an interesting way. He talks about how these tiny molecules in the bloodstream can control many of our behaviors and the behaviors in animals.
“The fact that complex behavioral patterns can be triggered by a tiny concentration of molecules coursing through the bloodstream, and that different amounts of these hormones, is something worth thinking about when it’s time to judge such matters as free will, individual responsibility, and law and order.” Page 238 “Shadows Of Forgotten Ancestors” by Carl Sagan.
Sagan then describes how testosterone effects the brain. In the brain there are receptor sites which chemically bind with testosterone. In the brain the testosterone centers are responsible for such behaviors as strutting, bullying, fighting, copulating, defending territory and fitting into a dominance hierarchy and or running it. If an animal has a high testosterone level he will want to dominate a large territory. He will dominate the whole territory including the other species who live in that territory. Animals such as mice do not see the connection between conception and the birth of the next generation of mice. Here the DNA is in control. The DNA gives the mice it’s sex drive so more mice can be made. Sagan describes what lengths mice will go just to have sex and just how much power the DNA have in controlling a species and continuing that species.
Sagan then goes from testosterone to estrogen. Estrogen is the opposite of testosterone because it curbs aggressiveness in females. Estrogen is calming. Progesterone increases the desire to protect and care for the young. These hormones are responsible for the feminine temperament. Here it should be noted that females have testosterone but just in small amounts. Occasionally a female can have too much testosterone and be aggressive and dominating like their male counter parts. Sagan then describes experiments where estrogen is given to both males and females. In both cases dominance and aggression is lowered. When testosterone is added to both males and females both become dominating and aggressive. Then Sagan sights an instance where there is a point when too much testosterone causes sterility. There is a hidden limit in nature where too much testosterone causes atrophy of the testicles. Nature has a turn off valve.
Sagan tells a story about an experiment on sparrows. Here this experiment shows how tension, anxiety and aggression creates the production of testosterone. Sagan sights the example of how sparrows normally establish their territories. Things are calm when a territory is well established but remove one of the sparrows from it’s territory and the tension automatically shoots up in neighboring areas because someone now has to fill the void or vacancy. Sparrows that had once lost in fights rise up to the challenge. Neighboring victors get more aggressive to protect their turf. The bloodstream of the sparrows are now filled with testosterone. Now all the sparrows are more aggressive. The same is true for most animals including humans. From here one could easily ask the question; Is American testosterone in both males and females higher than in a country like the former Soviet Union where anxiety is kept to a minimum and the struggle for existence is removed by their socialistic system?
The subject then switched to male ritual combat where the looser has a marked drop in testosterone. This seems to be true in animals ranging from pit vipers to primates. Sagan then talks about why even some plant eating animals guard their territory. He gives the example of birds that take nectar from flowers. In the morning when the nectar supply is plentiful it seems the birds do not guard their territory and allow stranger birds to partake. But by noon when the supply is dwindling they chase the strangers away. Scarcity makes one vicious and aggressively guard your territory. Fear has a smell. So if you are a mouse that is suddenly caused to fear all the other mice will run away from you. The predator will go for you because you are afraid.
Sagan then gets into how animals sound the alarm when a predator is near. The noise for a ground predator is different than the noise for a predator in the air. In lab tests on cockerels the female sounds the alarm only 13% of the time. Castrated cockerels were the least likely to sound the alarm. Regular cockerel males sounded the alarm most of the time. So it looks like testosterone also plays a role in a cockerel’s willingness to sound the alarm. If the bird were alone it just freezes and makes no sound. Warnings are only given if others of it’s species are present.
There is another molecule responsible for a peaceful demeanor. This molecule in the brain lessons aggression. More aggressive rats have less of this chemical in the brain. If a group of rats are very aggressive and killing one another is seen as common place, the other rats respond by becoming more aggressive and also kill. The threat spreads through out the community.
Sagan describes another experiment where there were pairs of rats that had to do a cooperative action in order to get the food. There were female pairs, normal male pairs, castrated male pairs, and male rats who lived alone until the experiment, female rat pairs that lived alone until the experiment and high testosterone males. The results were as fallows. Female and male castrates learned fairly quickly. Normal males and male castrates that got testosterone administered learned far more slowly. Normal male solitaries learned the slowest. The solitary males that were jolted with extra testosterone and males with high testosterone levels never learned at all. Females who lived alone, until the experiment, learned to do the experiment as well. The high testosterone males never learned because they could not cooperate and preferred violent combat instead of cooperating. The scientists concluded that “testosterone makes you stupid.” Page 237 “Shadows Of Forgotten Ancestors” by Carl Sagan. There are many experiments done with rats where the male chose a jolt of testosterone over food or fighting another rat which also gives a jolt in testosterone. Here we are reminded to wonder about humans both males and females. There are people that seem to enjoy and purposely cause fights. Could it be they are craving a testosterone jolt? It seems that testosterone has the quality of a drug because when you fill your bloodstream with testosterone you feel stronger, invincible and more brave. These facts in the lab on rats does make one naturally think of the human in your life that plays the role of the dominator even if the person is female. This desire to dominate and control is clearly the result of too much testosterone.
Sagan ends this chapter in an interesting way. He talks about how these tiny molecules in the bloodstream can control many of our behaviors and the behaviors in animals.
“The fact that complex behavioral patterns can be triggered by a tiny concentration of molecules coursing through the bloodstream, and that different amounts of these hormones, is something worth thinking about when it’s time to judge such matters as free will, individual responsibility, and law and order.” Page 238 “Shadows Of Forgotten Ancestors” by Carl Sagan.