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Wickedgirl
2011-09-16, 08:05
We're constantly evolving. What do you think the next steps gonna be and when will it happen? I thought about making a poll but I have no idea what the answers should be haha.

Machinehead
2011-09-16, 08:07
Elohim aliens would destroy our shitty race, and evolve us into something better.

Wickedgirl
2011-09-16, 08:13
okay...any serious answers?

Machinehead
2011-09-16, 08:15
We will have 2 penises

Happy?

duje
2011-09-16, 08:16
evolution is prevented, and will probably not happen in present circumstances

Wickedgirl
2011-09-16, 08:19
Why do you think it won't happen? Because of our environment?

Machinehead
2011-09-16, 08:19
evolution is prevented, and will probably not happen in present circumstances

At least non of us would witness it :|

Tyrannical
2011-09-16, 08:21
We've effectively eliminated most natural selective pressures. Humans will probably over time get less intelligent and acquire more genetic defects.

Dave
2011-09-16, 08:27
Okay I have a film for you to watch WickedGirl :P it's called Transcendent Man http://www.youtube.com/watch?v=SjhB6J23Qjs

I think we are going to evolve into what we want to, we are going to begin to modify ourselves and our bodies as we continue to improve artificial organ technology people will end up living forever. If our minds will evolve further I'm not sure if we will get smarter or not or if we will begin to rely more on computers to think for us.

duje
2011-09-16, 08:30
Why do you think it won't happen? Because of our environment?

because there are too many people.

there probably were some humans that had what could you call evolutionary steps in modern times(even minor ones), but it just melted and dispersed in mass of people.

Evolution works this way, lets say 1 baby is born with some kind of biological upgrade compared to other people, lets just say with IQ over 200, and that is also a dominant genetic trait.

In order for human race to evolve as a whole, all people would be needed to be related to that baby/person(or even another one who has same kind of an mutation by coincidence), and those guys who are related but didn't inherit that particular evo. step died off.

What could happen tho, is that some smaller and isolated group of people evolves parallel from humans as a whole.

Wickedgirl
2011-09-16, 08:31
haha...computers with consciousness. how exciting.

Dave
2011-09-16, 08:35
the full movie covers this guy who is a millionaire who is doing everything in his power to live forever and his theories on how humans will end up in 30 years.

also artificial organ technology that I'm talking about is not mechanical, they grow them and they are genetically compatible to your body, so you will be able to get new "parts" easily. They can already grow skin and ear cartilage right now and there was one guy who had a wind pipe grown for him.

duje
2011-09-16, 08:39
well, artificial evolution is defiantly possible

sgh
2011-09-16, 08:43
natural evolution works way too slow for us to discern the direction that it will take us. However, we can make some general predictions about where human-directed evolution (bio engineering, etc..) will take us. Hopefully the humans of the next few centuries will be engineered to be healthier, stronger and more intelligent.

Wickedgirl
2011-09-16, 08:45
Does anyone think it's pretty inevitable that genetic engineering and whatnot is going to become commonplace in the future?

duje
2011-09-16, 08:55
Does anyone think it's pretty inevitable that genetic engineering and whatnot is going to become commonplace in the future?

well it was done in the past by more slow and simple way.

Like you have meat cows, and milk cows, various dog breeds for various purposes, ...etc

As for actual lab engineering, yes.

I think its already done actually.

Jusarius
2011-09-16, 09:44
duje, I think you quite don't understand the mechanisms of evolution. Evolution happens whenever some gene clusters produce more viable offspring than others. Let's take an example: everywhere in the world tall men on average marry more often and have more children than shorter men. That's why those genes that affect growth are being selected for and the mean height will increase. That's evolution. However, evolution doesn't necessarily mean subjetive improvement but it's the force that constantly makes organisms better adapt to their environment. Evolution is all about who gives birth to more offspring, it's not necessarily about the classical "struggle for survival". If a there's a gene that makes women more susceptible to having quadruplets, it's very likely that gene will become much more common in the population gene pool only after a few generations assuming it's a country where there is no shortage of food and thus raising four children at a time doesn't reduce their survival probability (which was true in the past).

Another example: In Finland low class women give birth to more children than higher class women. On average, low class women are less intelligent. So although both groups have children who survive equally well, low class women have a slightly higher fertility ratio. That's why, if the trend continues, intelligence in Finland will drop in the future assuming there are no other selection pressures counteracting it.

Humans indeed evolve even today. There is evidence that gene forms that make us more intelligent have become more prevalent in the cities in just a few generations, for example.

upyours
2011-09-16, 10:12
Well I see humanity as a whole in developed countrys is getting taller and taller by the generation,and puberty seems to start earlier and earlier,especially in females.

yahooland
2011-09-16, 10:44
I think Europe will be populated by black people with little white influence, Not because i think they are superior but because they make more children than others.

Kwestos
2011-09-16, 11:15
As mechanisms of evolution in the last 50-100 years are different than were for most of history (main attributes were physical health, strenghth, immune system and physical adaptation to environment) due to medicine and social service and wealth distribution, at least in some countries it turned upside down.
Debate is, is it againts evolution- or it is part of evolution. Taking it literally, everything is evolution, just different kind, even physically weak, disabled and very ugly son of a millionaire, who will spread his genes.

(I dont neceserily agree with common perception that modern evolution 'saved' mainly benefit cheaters and unemployed, cause they are often physically strong, so I think many of them would survive anyway, its weak nerds in glasses or disabled children of rich people who are 'saved' most, compared to earlier criterias of evolution.
btw people interfered into mechanism of evolution in world of animals too.

p.s. I wonder, cause nowadays evolution does not promote the strongest or the most intelligent, but the most 'emotionally' intelligent, where would it go further.

Jusarius
2011-09-16, 11:22
As mechanisms of evolution in the last 50-100 years are different than were for most of history (main attributes were physical health, strenghth, immune system and physical adaptation to environment) Those attributes indeed likely were more important in our evolutionary past than today but the main features were still ingelligence and sexual selection from early on. We have had big brains that use up to 1/5 of the energy we consume, and we have had reduced muscle mass and strength for hundreds of thousands of years. That kind of shift in the usage of energy resoruces wouldn't have happened if strength dominated over wit. So intelligence and the ability to adapt to varying environments have been the keys already in the stone age. Already in the early human groups brute strength had little to do with climbing up the social ladder. Political skills had much more meaning. Men with status had women and thus lots of children that had resources with which to survive.

Kwestos
2011-09-16, 11:49
Those attributes indeed likely were more important in our evolutionary past than today but the main features were still ingelligence and sexual selection from early on. We have had big brains that use up to 1/5 of the energy we consume, and we have had reduced muscle mass and strength for hundreds of thousands of years. That kind of shift in the usage of energy resoruces wouldn't have happened if strength dominated over wit. So intelligence and the ability to adapt to varying environments have been the keys already in the stone age. Already in the early human groups brute strength had little to do with climbing up the social ladder. Political skills had much more meaning. Men with status had women and thus lots of children that had resources with which to survive.


Yes I am not saying that intelligence did not matter, but was only secondly important. Not in hierarchy, but in order- you cannot use your intelligence when you are dead.
You focused on one part of my post, maybe it was not that clear, but my main point was about physical strenght understood as health, immune system, survival skills etc.
Nowadays people with poor imune system, inborn deffects, serious health problems etc not only survive, but spread their genes. It mainly applies to rich societies and rich people, not the Third world, when mechanisms of evolution are still pretty 'traditional".
Before ages these poor, disabled, week, defected people would all die sooner or later (even children of Kings and princes, maybe having a bit bigger chances) and would not pass 'bad' genes. Nowadays, owed to medicine and wealth, 'bad' genes are passed, in a way againts the rules of evolution- or maybe not against, but as a part of evolution, which now promotes different things.

Cynewald
2011-09-16, 11:51
I think todays society doesn't favour small males, it favours the tall - the way forward is tall, so I think men will average out at about 7ft tall in future generations (in 500 - 1000 years time), with a larger average size penis. In 20'000 years time I think the male penis would of developed barbs for pleasing females.

Females will remain at about 5ft7 tall and will all be doll-like in appearance and very neotenic.

Jusarius
2011-09-16, 12:04
Yes I am not saying that intelligence did not matter, but was only secondly important. Not in hierarchy, but in order- you cannot use your intelligence when you are dead. Warfare and fighting also was more about wit in the past, who had more allies (friends) that would help and who could make the best weapons. Neanderthals were much stronger than modern humans but we prevailed instead of them. Researchers now believe it's because we were better at creating and operating in large social networks. That's why separated and small Neanderthal groups were dominated by larger networks of modern humans although the size of separate groups were equal. That's just an example on population level but it goes with individuals, too.


You focused on one part of my post, maybe it was not that clear, but my main point was about physical strenght understood as health, immune system, survival skills etc.
Nowadays people with poor imune system, inborn deffects, serious health problems etc not only survive, but spread their genes. It mainly applies to rich societies and rich people, not the Third world, when mechanisms of evolution are still pretty 'traditional".
Before ages these poor, disabled, week, defected people would all die sooner or later (even children of Kings and princes, maybe having a bit bigger chances) and would not pass 'bad' genes. Nowadays, owed to medicine and wealth, 'bad' genes are passed, in a way againts the rules of evolution- or maybe not against, but as a part of evolution, which now promotes different things. I focused on that one part because that was the only one I disagreed with you on. :) I think too that modern medicine and welfare states allow "bad" genes to spread equally well as the "good" ones. That's why it's likely most of us are completely dependent on drugs and other medical treatment in the future. Also new mutations are not eliminated so we also gain an inreasing number of new diseases which have to be treated. It will be a bright future for drug industry! I think, however, that genetic engineering will correct those "bad" genes only if we want. That would require the permission to manipulate germ cell lines to cure also the coming generations. I think we will be forced to "repair" the germ lines at some point.

Alej
2011-09-16, 12:24
because there are too many people.

there probably were some humans that had what could you call evolutionary steps in modern times(even minor ones), but it just melted and dispersed in mass of people.

Evolution works this way, lets say 1 baby is born with some kind of biological upgrade compared to other people, lets just say with IQ over 200, and that is also a dominant genetic trait.

In order for human race to evolve as a whole, all people would be needed to be related to that baby/person(or even another one who has same kind of an mutation by coincidence), and those guys who are related but didn't inherit that particular evo. step died off.

What could happen tho, is that some smaller and isolated group of people evolves parallel from humans as a whole.

Like the Papuan high landers?

duje
2011-09-16, 12:35
duje, I think you quite don't understand the mechanisms of evolution. Evolution happens whenever some gene clusters produce more viable offspring than others. Let's take an example: everywhere in the world tall men on average marry more often and have more children than shorter men. That's why those genes that affect growth are being selected for and the mean height will increase. That's evolution. However, evolution doesn't necessarily mean subjetive improvement but it's the force that constantly makes organisms better adapt to their environment. Evolution is all about who gives birth to more offspring, it's not necessarily about the classical "struggle for survival". If a there's a gene that makes women more susceptible to having quadruplets, it's very likely that gene will become much more common in the population gene pool only after a few generations assuming it's a country where there is no shortage of food and thus raising four children at a time doesn't reduce their survival probability (which was true in the past).

Another example: In Finland low class women give birth to more children than higher class women. On average, low class women are less intelligent. So although both groups have children who survive equally well, low class women have a slightly higher fertility ratio. That's why, if the trend continues, intelligence in Finland will drop in the future assuming there are no other selection pressures counteracting it.

Humans indeed evolve even today. There is evidence that gene forms that make us more intelligent have become more prevalent in the cities in just a few generations, for example.

you took common trait, which is tallness, however you cant stop short men and women having short offspring.

you took more probable route, but you still said same thing I did.

What has happened in a world is stagnation of progress, due to our technological advances you can survive just fine and have offspring as a dumb and weak person.
So basically artificial evolution could be the key, or some kind of caste system which is basically like pedigree breeding.

Why I think average intelligence wont drop, is because I think high IQ trait, is dominant genetic trait, so even if those of lower IQ have more children, occasional mixing will normalise it.
At least I hope so, because if average IQ drops, than it isn't evolution but devolution

Jusarius
2011-09-16, 12:52
duje, did you read my answer with thought? Because from it you can find counter-arguments to all what you wrote. But let's repeat...


you took common trait, which is tallness, however you cant stop short men and women having short offspring. As I wrote earlier, both have children which survive but taller men have more on average. If tall men (let's say >185 cm) have 2.6 children on average whereas shorter men (<185 cm) have 2.2 children, it's a mathematical fact that those "tall genes" "breed out" those "short genes" in not so many generations. Most of evolutionary changes aren't about struggling and somehow "preventing to reproduce". Try to get that it's about which is the best. Good is not enough. Alleles are eliminated if they're better than the "competing" allele although they would "be enough for survival" per se.


What has happened in a world is normalization of progress, due to our technological advances you can survive just fine and have offspring as a dumb and weak person.
So basically artificial evolution could be the key, or some kind of caste system which is basically like pedigree breeding. No, read my answer above.


Why I think average intelligence wont drop, is because I think high IQ trait, is dominant genetic trait, so even if those of lower IQ have more children, occasional mixing will normalise it. I'm not going into the basics of population genetics but that what you said isn't true. If (I don't know what's the situtation now) "dumb" genes are selected for in Finland for example (people who have them have more offspring), then there will be a drop in intelligence. Intelligence is a very polygenic trait and you can't say that the genes that increase intelligence are somehow "more dominant". That isn't true. Even if they were and if there was a negative selection force against them, the mean IQ would still drop. In every generation, there would be less and less of those "intelligence genes".


At least I hope so, because if average IQ drops, than it isn't evolution but devolution I explained this earlier, too. Every change in population gene pool is called evolution. There's no universal ideal of what's "progressive" or "good", just adaptation and changing. In evolutionary sense, only those attributes that increase the probability to produce viable offspring are good. All other attributes are just means to reaching that goal.

---------- Post added 2011-09-16 at 15:04 ----------


haha...computers with consciousness. how exciting. There's nothing supernatural in our brains. Neurons are electric switches analogous to those in computers. Consciousness is gained after a system reaches a certain level of complexity and I see no reason why future computers wouldn't be able to do that.

"haha...machines that can fly. how exciting." - an unknown guy in the 13th century.

Ozrage
2011-09-16, 13:31
Illustrerad Vetenskap (http://en.wikipedia.org/wiki/Science_Illustrated) had a piece on the Future Of Man a few years ago. I remember they described four possible outcomes. One I think had eugenics involved and they had a blonde nordic posterboy. Then there was the back to nature road. Looked like a wog cromagnid type I think.

Then there was the robotnic man with augmentations like in Deus Ex. Superiority through technology and altered bodies. And the last was a spaceman. Suited for low gravity, darkness and perhaps for life on a space station. Looked like a humanoid race from the Star Trek universe. Slim, grey and bald with big eyes.

Don't know where my paper is. But it was something like that.

cafman21
2011-09-16, 13:32
Human will probably be taller, less hairy and hopefully less stupid.

larali
2011-09-16, 13:36
Does anyone think it's pretty inevitable that genetic engineering and whatnot is going to become commonplace in the future?

I really hope not. That stuff disturbs me on a very deep level.

I do hope that we will be able to grow organs for transplantation. I think that will be the next major physiological breakthrough, as well as the cure for cancer. I don't think that we will change much, just begin to live longer. The issue will be what to do with all the old people, instead of designer babies.

duje
2011-09-16, 13:37
duje, did you read my answer with thought? Because from it you can find counter-arguments to all what you wrote. But let's repeat...

As I wrote earlier, both have children which survive but taller men have more on average. If tall men (let's say >185 cm) have 2.6 children on average whereas shorter men (<185 cm) have 2.2 children, it's a mathematical fact that those "tall genes" "breed out" those "short genes" in not so many generations. Most of evolutionary changes aren't about struggling and somehow "preventing to reproduce". Try to get that it's about which is the best. Good is not enough. Alleles are eliminated if they're better than the "competing" allele although they would "be enough for survival" per se.





Can you backup claim that tall men will have/have more children?

larali
2011-09-16, 13:40
There's nothing supernatural in our brains. Neurons are electric switches analogous to those in computers. Consciousness is gained after a system reaches a certain level of complexity and I see no reason why future computers wouldn't be able to do that.

Creeeeeepy.

Jusarius
2011-09-16, 13:43
I really hope not. That stuff disturbs me on a very deep level. I think it's better to have controlled (when we can be sure they're safe) genetic engineering than random mutations which happen millions each day in every human. Those mutations caused by e.g. the sun are however called "natural". Some of those mutations for example can cause teeth to grow in the ovaries in ovarian cancer. I think it be immoral if you prevented genetic engineering that would make us resistant to cancer.

---------- Post added 2011-09-16 at 15:47 ----------


Can you backup claim that tall men will have/have more children?

A scientific article from Nature: http://www.ncbi.nlm.nih.gov/pubmed/10646589

In more recent studies, it has been found out that it's obvious and certain that women find taller men sexier and that tall men have more extra-marital relationships (because they have more opportunities). Also, extremely tall men have less children than average. So it's a U shape curve with it's top in the taller corner.

duje
2011-09-16, 13:51
A scientific article from Nature: http://www.ncbi.nlm.nih.gov/pubmed/10646589

don't wont to read it, but can you tell me does it tell it is easier time finding mate for reproduction, or they are actually having more children.

If its more children, doesn't that mean by your logic, that tall men are dumb?

Jusarius
2011-09-16, 13:59
don't wont to read it, but can you tell me does it tell it is easier time finding mate for reproduction, or they are actually having more children. They marry more often and have more extramarital affairs. Both marriage and extramarital sex increase the probability of having children. :) So to my knowledge, tall men don't have bigger families on average.


If its more children, doesn't that mean by your logic, that tall men are dumb? What?! Can you explain me what logic made you reach such conclusion?

duje
2011-09-16, 14:05
They marry more often and have more extramarital affairs. Both marriage and extramarital sex increase the probability of having children. :) So to my knowledge, tall men don't have bigger families on average.

What?! Can you explain me what logic made you reach such conclusion?


Dont you know what you write? :lol:

You said dumb people have more children, thus more dumb children will be born, and because of that average IQ will drop. :lol:

You also said tall men have more children, so people will become taller over time

2+2=4

basic deductive logic

well, this is according to your POV, which i don't share

Jusarius
2011-09-16, 14:14
You said dumb people have more children, thus more dumb children will be born, and because of that average IQ will drop. :lol:

You also said tall men have more children, so people will become taller over time

So if both of those are true in a population, according to your "deductive logic" it means that taller men are dumb? Come on!

If the trend is that houses are becoming more expensive all the time and if there's a trend that people choose to paint their houses red, does it mean that new red houses are more expensive than the houses that are not red?

I can't believe I must explain this, but there are thousands of attributes in human evolution selected for and against at the same time but most of them are not connected to each other.

So again: If a population is getting taller and dumber, it doesn't mean that tall people in that population are dumber than the shorter ones. It can be the opposite even. Think about that very carefully with thought. So the genes that cause tallness don't cause dumbess and they are not connected. In summer time Finland, both consumption of ice-cream and the incidence of drownings increase. Do you automatically assume eating ice-cream causes drowning?

In our (hypothetical) example where "tall genes" and "dumb genes" are selected for:
TRUE: People will get taller
TRUE: People will get dumber
TRUE: People are taller and dumber than their parents
FALSE: In a certain age group, intelligence is correlated with height

duje
2011-09-16, 14:37
So if both of those are true in a population, according to your "deductive logic" it means that taller men are dumb? Come on!

If the trend is that houses are becoming more expensive all the time and if there's a trend that people choose to paint their houses red, does it mean that new red houses are more expensive than the houses that are not red?

I can't believe I must explain this, but there are thousands of attributes in human evolution selected for and against at the same time but most of them are not connected to each other.

So again: If a population is getting taller and dumber, it doesn't mean that tall people in that population are dumber than the shorter ones. It can be the opposite even. Think about that very carefully with thought.

eventually yes, according to you, we will be all tall and dumb :lol:

Yea, I can see that, I was wrong, and perhaps bit rash in my thought. :p


However i still don't share your POV, because there are far more variables than you work with.

Jusarius
2011-09-16, 14:48
However i still don't share your POV, because there are far more variables than you work with. But all that matters regarding height development is the fertility ratio of tall vs. shorter men. I admit the intelligence thing isn't that staightforward. That was only a hypothetical example although both of those claims are true (low class women are more stupid and that they reproduce more). Trends change so quickly. It's up to even the state social benefit systems; if Finnish welfare system stops supporting financially those mothers that have children, then the situation most likely changes as low-income women can't afford to have children anymore.

If there was a selection pressure towards dumber people, I think it wouldn't make us chimp-like dumb. That's because after some generations intelligence would have dropped to a level where dumb people would have difficulties in coping and raising their children safely. So intelligence would regain it's positive selective force then.



---------- Post added 2011-09-16 at 16:52 ----------


Yea, I can see that, I was wrong, and perhaps bit rash in my thought. :p Everybody is sometimes :lol:

duje
2011-09-16, 14:55
But all that matters regarding height development is the fertility ratio of tall vs. shorter men. I admit the intelligence thing isn't that staightforward. That was only a hypothetical example although both of those claims are true (low class women are more stupid and that they reproduce more). Trends change so quickly. It's up to even the state social benefit systems; if Finnish welfare system stops supporting financially those mothers that have children, then the situation most likely changes as low-income women can't afford to have children anymore.

there is also another huge amount human factors, weather it be to GE, or something like 1 child rule like in China, what you said, some big event, nature of gene transfer(dominant vs recessive genes), maybe less smart people equals more wars, and more dumb die off ...etc

Also you thought that every change is evolution, thus you deny devolution.
You said bigger families have more chance of success, and that's not quite true, especially in modern world, and it depends on social circumstances.
What i am trying to say is that in some scenarios people who tend to bread more are less adopted to environment they live in.

Jusarius
2011-09-16, 15:08
Also you thought that every change is evolution, thus you deny devolution. Devolution is rejected in modern biology. From wikipedia (devolution):


This view (devolution) is rejected by modern evolutionary theory, in which adaptation arises from natural selection of forms best suited to the environment, and so can lead to loss of features when these features are costly to maintain. Thus for cave dwelling animals the loss of eyes arises because it is an advantage, not degeneracy.


You said bigger families have more chance of success All I said was that assuming there are plenty of resources and if all children have equally good chances of survival regardless of the amount of them, then having as much children as possible is adaptive and more successful in evolutionary sense. And I guess we are arguing about evolution here. Those conditions are true in most of Europe. However, it doesn't have to mean bigger families. Men can increase their evolutionary success by conceiving women without raising them or forming a family with each women they have sex with.


What i am trying to say is that in some scenarios people who tend to bread more are less adopted to environment they live in. If those children survive and have offspring of their own, then they are better adapted to their environment. It's all that matters in evolution.

duje
2011-09-16, 15:21
Devolution is rejected in modern biology. From wikipedia (devolution):



All I said was that assuming there are plenty of resources and if all children have equally good chances of survival regardless of the amount of them, then having as much children as possible is adaptive and more successful in evolutionary sense. And I guess we are arguing about evolution here. Those conditions are true in most of Europe. However, it doesn't have to mean bigger families. Men can increase their evolutionary success by conceiving women without raising them or forming a family with each women they have sex with.

If those children survive and have offspring of their own, then they are better adapted to their environment. It's all what matters in evolution.

Devolution isnt sustainable in nature, its not it cant happen.

In human world is possible and sustainable, hmm, lets see, hereditary illnesses that would kill of genetic line in nature, lives on in society because of human advancement in technology.
So devolution isnt possible in nature, however its possible in human civilization.
Because of technology, we started to stagnate on biological level, but that can change with use of technology, or with social laws.

This was point of my post you tried to bash.

Also we are not talking about utopia, to much breeding will make resources thin even in almost ideal world, thus something will have to change.
Imagine if lions breed on a level of rats, they would die off, and that would be devolution for them, but it will not happen in nature because of balance, and because lions are dumb

amerinese
2011-09-16, 15:50
Here's my vision of the future of mankind:

http://www.youtube.com/watch?v=BXRjmyJFzrU

Tuck
2011-09-16, 15:55
we will grow wings and fly, lol

duje
2011-09-16, 15:58
Here's my vision of the future of mankind:

http://www.youtube.com/watch?v=BXRjmyJFzrU

be honest, its a vision of man who was behind the video :lol:

amerinese
2011-09-16, 15:59
be honest, its a vision of man who was behind the video :lol:

You're right. His name is Mike Judge, and he is a visionary.

amenoameno
2011-09-17, 14:55
Larger heads and brains like Einstein, Rainman and other geniuses?

yahooland
2011-09-19, 12:09
Men with bigger penis

http://www.guardian.co.uk/science/2010/may/06/women-penis-size

"The human penis has evolved the unusual system of vasocongestion to achieve erection, making the erect organ far more flexible than that of other primate species.

This unique adaptation is thought to have been selected through female mate choice, and by the time Homo erectus arrived on the scene, the hominid penis was significantly longer, fatter and more bendy than our ape cousins'. It has even been theorised that bipedalism evolved in humans to allow the fashionably new, larger, flexible penis to be displayed to discerning females"

---------- Post added 2011-09-19 at 22:18 ----------

"Since humans are bipedal the penis is a highly noticeable feature. It has been suggested that in ancestral environments, males may have selected for bigger penises by using them as a status symbol. This would mean using penises to decide social standing. The male with the largest penis would be the one with the most power, therefore the male with the most access to females."

http://www.associatedcontent.com/article/42665/penis_evolution_intersexual_and_intrasexual_pg4.ht ml?cat=7