Author Topic: Human Evolution  (Read 4390 times)

Offline Tubalard

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Human Evolution
« on: October 03, 2011, 09:21:56 PM »
This thread is dedicated at changing the mind of the deniers.  Repent CTC for we will forgive you anti-evolution transgressions.

Humans Are Still Evolving, Study Says
LiveScience.comBy Jennifer Welsh | LiveScience.com – 5 hrs ago


Humans, like all other organisms on Earth, are subject to the pressures of evolution. New research suggests that even in relatively modern societies, humans are still changing and evolving in response to the environment.

"Whether humans could or could not evolve in modern times could have interesting implications," study researcher Emmanuel Milot, of the University of Quebec in Montreal, told LiveScience. It could help us understand changing trends for the different traits of a population.

By studying an island population in Quebec, the researchers found a genetic push toward younger age at first reproduction and larger families. This is the first direct evidence of natural selection in action in a relatively modern human population.

Past studies have hinted our species continues to evolve, with research showing changes to hundreds of genes in the human genome over the past 10,000 years; in addition, skull measurements suggest our brains have been shrinking over the last 5,000 years or so.

An island population

The study used data from 30 families who settled on île aux Coudres, located in the St. Lawrence River outside of Quebec City, between 1720 and 1773. A church on the island held historical records of all births, deaths and marriages on the island, from which researchers were able to build intensive family trees.

The researchers analyzed the data from women who married between 1799 and 1940, comparing their relations, any social, cultural or economic differences, and the age they had their first child.

The researchers found that over a 140-year period, age at first reproduction dropped from 26 to 22, with somewhere between 30 percent and 50 percent of this variation being explained by genetic variation in the population, not by other factors, such as changes in cultures or social attitudes.

"We think, traditionally, that the changes in human population are mainly cultural, which is why a non-genetic hypothesis is given priority over a genetic or evolutionary hypothesis, whether or not there is data to support that," Milot said. "We have data that we analyzed from the genetic and nongenetic point of view, and we find that the genetic factors are stronger."

Naturally selected population

Because of the populations' lack of birth control, families in this population ended up being very large, and since fertility wasn't altered by outside influences, each couple was likely to reach maximum fertility. [Countdown: The History and Future of Birth Control]

The researchers didn't look at which genes might have changed over time, but they suggest reasons for the age change could include differences in fertility and how early a woman hits puberty, or even heritable personality traits that would nudge a woman to procreate earlier. These genetic factors would be changing in response to the natural selection for a higher number of kids overall.

"In that particular population, selective pressure seemed pretty constant for the study period," Milot said. "Maybe it has to do because it has a newly founded population and it was not disadvantageous to have big families."

A newly founded population would have the resources to support large families, and more kids mean the higher likelihood that one's genes would survive well into the future.

Evolving humans

Seeing natural selection in modern populations is incredibly difficult. Because this population was pretty highly related and relatively cut off from outside populations, the correlation between genetic factors and age at first reproduction was easier to see.

"What we learn from that population is that evolution is possible in relatively modern times in modern humans," Milot said. "Where it is going to occur and in what ways is a different question."

Steve Sterns, a researcher from Yale University who wasn't involved in the study, told LiveScience in an email that the work "is an important advance, because it demonstrates a genetic response to selection in a recent, almost a contemporary, human population."

The study was published was published Monday (Oct. 3) in the journal Proceedings of the National Academy of Sciences.
Abortion is the violent act of ending human development.

Protect the precious life of your young at all cost.

Offline Tubalard

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Re: Human Evolution
« Reply #1 on: October 03, 2011, 11:11:48 PM »
Too many forums.  Reminds of a control strategy using compartamentalized knowledge.
Abortion is the violent act of ending human development.

Protect the precious life of your young at all cost.

Offline Ray Brinzer

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Re: Human Evolution
« Reply #2 on: October 03, 2011, 11:17:31 PM »
It is a control strategy, though rest assured, there's precious little knowledge being compartmentalized.  The rationale may be found in the announcement.

Offline Tubalard

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Re: Human Evolution
« Reply #3 on: October 03, 2011, 11:25:26 PM »
Knowledge is overated anyway!
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Offline Ray Brinzer

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Re: Human Evolution
« Reply #4 on: October 03, 2011, 11:36:26 PM »
I should note that thus far I have heard two complaints:  yours, and another one sent privately.  Some other people have expressed satisfaction in private.  If people wish to debate the matter, they can reply to the announcement, or start a thread under Politics >> The Open Mat.  If there seems to be general agreement that the category isn't a good thing, we'll be happy to reconsider the matter.

Offline ctc

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Re: Human Evolution
« Reply #5 on: October 04, 2011, 08:59:29 AM »
Funny stuff.  Where did you get this - Comedy Central?  Check out this gem -

By studying an island population in Quebec, the researchers found a genetic push toward younger age at first reproduction and larger families.
 This is the first direct evidence of natural selection in action in a relatively modern human population.



Now, that is so convincing.   :D

We are evolving.  DNA is becoming more and more damaged.  Thank God for doctors, surgeries, medicines, pace makers, glasses, and wheel chairs.
"We can state with conviction, therefore, that a man's support for absolute government is in direct proportion to the contempt he feels for his country" - Alexis de Tocqueville

Offline Cougar1

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Re: Human Evolution
« Reply #6 on: October 04, 2011, 09:33:16 AM »
Quote
By studying an island population in Quebec, the researchers found a genetic push toward younger age at first reproduction and larger families.
 This is the first direct evidence of natural selection in action in a relatively modern human population.

I have to admit that's quite a stretch.
“Once abolish the God and the government becomes the God.”

― G.K. Chesterton

Offline coachsparky

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Re: Human Evolution
« Reply #7 on: October 04, 2011, 09:50:53 AM »
Funny stuff.  Where did you get this - Comedy Central?  Check out this gem -

By studying an island population in Quebec, the researchers found a genetic push toward younger age at first reproduction and larger families.
 This is the first direct evidence of natural selection in action in a relatively modern human population.



Now, that is so convincing.   :D

We are evolving.  DNA is becoming more and more damaged.  Thank God for doctors, surgeries, medicines, pace makers, glasses, and wheel chairs.

DNA is becoming more and more damaged?  WTF does the crazy texas coach get this BS.  What a tard he is! ::)

Of course if we measure it by his DNA I would have to agree, something seriously messed up there.
We can easily forgive a child who is afraid of the dark;  the real tragedy of life is when men are afraid of the light.

Bigotry disguised as religious liberty is still BIGOTRY

Offline mspart

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Re: Human Evolution
« Reply #8 on: October 04, 2011, 04:57:16 PM »
Quote
By studying an island population in Quebec, the researchers found a genetic push toward younger age at first reproduction and larger families.
 This is the first direct evidence of natural selection in action in a relatively modern human population.

I have to admit that's quite a stretch.

Quite a stretch!!!  Yep.  If I understand it correctly, this means that women were marrying earlier and having babies sooner.  Remember, throughout history, women generally are able to conceive by the time they are 13-15.  So how is this proof of evolution? 

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Re: Human Evolution
« Reply #9 on: October 04, 2011, 05:36:37 PM »
The proof you seek can be found in run down trailer parks throughout America.

Offline Tubalard

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Re: Human Evolution
« Reply #10 on: October 05, 2011, 08:21:25 PM »
Funny stuff.  Where did you get this - Comedy Central?  Check out this gem -

By studying an island population in Quebec, the researchers found a genetic push toward younger age at first reproduction and larger families.
 This is the first direct evidence of natural selection in action in a relatively modern human population.



Now, that is so convincing.   :D

We are evolving.  DNA is becoming more and more damaged.  Thank God for doctors, surgeries, medicines, pace makers, glasses, and wheel chairs.

I knew you were going to continue to live in the nile.
Abortion is the violent act of ending human development.

Protect the precious life of your young at all cost.

Offline Tubalard

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Re: Human Evolution
« Reply #11 on: October 05, 2011, 09:16:35 PM »
I should note that thus far I have heard two complaints:  yours, and another one sent privately.  Some other people have expressed satisfaction in private.  If people wish to debate the matter, they can reply to the announcement, or start a thread under Politics >> The Open Mat.  If there seems to be general agreement that the category isn't a good thing, we'll be happy to reconsider the matter.

Satire killer!
Abortion is the violent act of ending human development.

Protect the precious life of your young at all cost.

Offline coachsparky

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Re: Human Evolution
« Reply #12 on: October 16, 2011, 12:35:17 PM »
From "The Blank Slate" Steven Pinker;

Quote
Evolution is central to understanding of life, including human life.  Like all living things, we are outcomes of natural selection; we got here because we inherited traits that allowed our ancestors to survive, find mates, and reproduce.  This momentous fact explains our deepest striving: why having a thankless child is sharper than a serpent’s tooth, why it is a truth universally acknowledged that a single man in possession of good fortune must be in want of a wife, why we do not go gentle into the good night but rage, rage against the dying of the light.
Evolution is central to understanding ourselves because signs of design in human beings do not stop at the heart or the eye.  For all it exquisite engineering, an eye is useless without a brain.  Its output is not the meaningless patterns of a screen saver, but raw material for circuitry that computes a representation of the external world.  That representation feeds other circuits that make sense of the world.  That representation feeds other circuits that make sense of the world by imputing causes to events and placing them in categories that allow useful predictions.  And that sense-making, in turn, works in the service of motives such as hunger, fear, love, curiosity, and the pursuit of status and esteem.  As I mentioned, abilities that seem effortless to us--categorizing events, deducing cause and effect, and pursuing conflicting goals—are major challenges in designing and intelligent system, ones that robot designers strive, still unsuccessfully to duplicate.
So signs of engineering in the human mind go all the way up, and that is why psychology has always been evolutionary.  Cognitive and emotional faculties have always been recognized as nonrandom, complex and useful, and that means they must be products either of divine design or of natural selection.  But until recently evolution was seldom explicitly invoked within psychology, because with many topics, folk intuitions about what is adaptive are good enough to make headway.  You don’t need an evolutionary biologist to tell you that depth perception keeps an animal from falling off cliffs and bumping into trees, that thirst keeps it from drying out, or that it’s better to remember what works and what doesn’t than to be an amnesiac.
But with other aspects of our mental life, particularly in the social realm, the function of faculty is not so easy to guess.  Natural selection favors organisms that are good at reproducing in some environment.  When the environment consists of rocks, grass, and snakes, it’s fairly obvious which strategies work and which ones don’t.  But when the relevant environment consists of other members of the species evolving their own strategies, it is not so obvious.  In the game of evolution is it better to be monogamous or polygamous? Gentle or aggressive? Cooperative or selfish?  Indulgent with children or stern with them? Optimistic, pragmatic, or pessimistic?
For questions like these, hunches are unhelpful, and that is why evolutionary biology has increasingly been brought into psychology.  Evolutionary biologist tell us that it is a mistake to think of anything conducive to people’s well-being—group cohesion, the avoidance of violence, monogamous pair bonding, aesthetic pleasure, self-esteem—as an “adaptation.”  What is “adaptive” in everyday life is not necessarily an “adaptation” in the technical sense of being a trait that was favored by natural selection in a species’ evolutionary history.   Natural selection is the morally indifferent process in which the most effective replicators outreproduce the alternatives and come to prevail in the population.  The selected genes will therefore be the “selfish” ones, in Richard Dawkins’s metaphor—more accurately, the megalomaniacal ones, those that make the most copies of themselves.  An adaptation is anything brought about by the genes that helps them fulfill this metaphorical obsession, whether or not it also fulfills human aspirations.  And this is a strikingly different conception from our everyday intuitions about what our faculties were designed for.
The megalomania of the genes does not mean that benevolence and cooperation cannot evolve, any more than the law of gravity proves that flight cannot evolve.  It means only that benevolence, like flight, is a special state of affairs in need of an explanation, not something that just happens.  It can evolve only in particular circumstances and has to be supported by a suite of cognitive and emotional faculties.  Thus benevolence (and other social motives) must be dragged into the spotlight rather than treated as part of the furniture.  In the sociobiological revolution of the 1970s, evolutionary biologists replaced the fuzzy feeling that organisms evolve to serve the greater good with deductions of what kinds of motives are likely to evolve when organisms interact with offspring, mates, siblings, friends, strangers, and adversaries.
We can easily forgive a child who is afraid of the dark;  the real tragedy of life is when men are afraid of the light.

Bigotry disguised as religious liberty is still BIGOTRY

Offline coachsparky

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Re: Human Evolution
« Reply #13 on: October 16, 2011, 01:43:15 PM »
More for Pinker's "The Blank Slate;"

Quote
Human nature is a scientific topic, and as new facts come in, our conception of it will change.  Sometimes the facts may show that a theory grants our minds too much innate structure.  For example, perhaps our language faculties are equipped not with nouns, verbs, adjectives, and prepositions but only with a distinction between more nounlike and more verblike parts of speech.  At other times a theory may turn out to have granted our minds too little innate structure.  No current theory of personality can explain why both members of a pair of identical twins reared apart liked to keep rubber bands around their wrists and pretend to sneeze in crowded elevators.
Also up for grabs is exactly how our minds use the information coming from the senses.  Once our faculties for language and social interaction are up and running, some kinds of learning may consist of simply recording information for future use, like the name of a person or the content of a new piece of legislation.  Others may be more like setting a dial, flipping a switch, or computing tan average, where the apparatus is in place but a parameter is left open so the mind can track variation in the local environment.  Still others may use the information provided by all normal environments, such as the presence of gravity or the statistics of colors and lines in the visual field, to tune up our sensorimotor systems.  There are yet other ways that nature and nurture might interact, and many will blur the distinction between the two.
This book is based on the estimation that whatever the exact picture turns out to be, a universal complex human nature will be part of it.  I think we have reason to believe that the mind is equipped with a battery of emotions, drives, and faculties for reasoning and communicating, and that they have a common logic across cultures, are difficult to erase or redesign from scratch, were shaped by natural selection acting over the course of human evolution, and owe some of their basic design (and some of their variation) to information in the genome.  This general picture is meant to embrace a variety of theories present and future, and range of foreseeable scientific discoveries.   
We can easily forgive a child who is afraid of the dark;  the real tragedy of life is when men are afraid of the light.

Bigotry disguised as religious liberty is still BIGOTRY