Inbreeding leads to an increase in homozygosity, that is, the same allele at the same locus on both members of a chromosome pair. This occurs because close relatives are much more likely to share the same alleles than unrelated individuals. This is especially important for recessive alleles that happen to be deleterious, which are harmless and inactive in a heterozygous pairing, but when homozygous can cause serious developmental defects. Such offspring have a much higher chance of death before reaching the age of reproduction, leading to what biologists call inbreeding depression, a measurable decrease in fitness due to inbreeding among populations with deleterious recessives. Recessive genes which can contain various genetic problems have a tendency of showing up more often if joined by someone who has the same gene. If a son who has hemophilia becomes intimate with his sister who may have the same gene for hemophilia, and they have a child, the odds are in favor that the child will have hemophilia as well.
Some anthropologists are critical of including biology in the study of the incest taboo, and have argued that there can be no biological basis for inbreeding aversion because inbreeding may in fact be a good thing. Leavitt (1990) is a good representative of this point of view, writing that "small inbreeding populations, while initially increasing their chances for harmful homozygotic recessive pairings on a locus, will quickly eliminate such genes from their breeding pools, thus reducing their genetic loads" (Leavitt 1990, p.974)
Other specialists claim that this notion betrays a misunderstanding of basic genetics and natural selection. They argue that, while technically possible, the proposed positive long-term effects of inbreeding are almost always unrealized because the short-term fitness depression is enough for selection to discourage inbreeding. Such a scenario has only occurred under extremely unusual circumstances, either in major population bottlenecks, or forced artificial selection by animal husbandry. In order for such a "purification" to work, the offspring of close mate pairings must only be homozygous dominant (free of bad genes) and recessive (will die before reproducing). If there are heterozygous offspring, they will be able to transmit the defective genes without themselves feeling any effects. What's more, this model does not account for multiple deleterious recessives (most people have more than one), or multi-locus gene linkages. The introduction of mutations negates the weeding out of bad genes, and evidence exists that homozygous individuals are often more at risk to pathogenic predation. Because of these complications, it is extremely difficult to overcome the initial "hump" of fitness penalties incurred by inbreeding. (see Moore 1992, Uhlmann 1992)
Therefore, it is not surprising that inbreeding is uncommon in nature, and most sexually reproducing species have mechanisms built in by natural selection to avoid mating with close kin. Pusey & Worf (1996) and Penn & Potts (1999) both have found evidence that some species possess evolved psychological aversions to inbreeding, via kin-recognition heuristics.
Given such overwhelming evidence of inbreeding depression as being an important force in sexual reproduction, evolutionary psychologists have argued that humans should possess similar psychological heuristics against incest. The Westermarck effect is one strong piece of evidence in favor of this, indicating that children who are raised together in the same family find each other sexually uninteresting, even when there is strong social pressure for them to mate. In what is now a key study of the Westermarck's hypothesis, the anthropologist Melford E. Spiro demonstrated that inbreeding aversion between siblings is predicatably linked to co-residency. In a cohort study of children raised as communal, that is to say, fictive, siblings in the Kiryat Yedidim kibbutz in the 1950s, Spiro found practically no intermarriage between his subjects as adults, despite positive pressure from parents and community. The social experience of having grown up as brothers and sisters created an incest aversion, even though genetically speaking the children were not related.
Further studies have backed up the hypothesis that some psychological mechanisms are in play that "turn off" children who grow up together. Spiro's study is corroborated by Fox (1962), who found similar results in Israeli kibbutzum. Likewise, Wolf and Huang (1980) report similar aversions in Taiwanese "child" marriages, where the future wife was brought into the family and raised together with her fiancee. Such marriages were notoriously difficult to consummate, and for unknown reasons actually led to decreased fertility in the women. Lieberman et. al (2003) found that childhood co-residency with an opposite-sex individual strongly predicts moral sentiments regarding third-party sibling incest, further supporting the Westermark hypothesis.
While the exact nature of kin-recognition psychology is still waiting to be defined, and to what degree it can be overcome by cultural forces is as yet poorly understood, an overwhelming body of research now shows that evolutionary biology and evolved human psychology plays a central role in human aversion to incest.
AND FOR YOUR INFORMATION CAIN AND ABLE WERE NOT BORN IN THE GARDEN OF EDEN!! DO NOT RESPOND TO THIS LADY'S QUESTION WITHOUT EVEN KNOWING YOUR BIBLE.. IN GEN 3:23 ADAM AND EVE HAVE ALREADY BEEN BANISHED FROM THE GARDEN AND CREATED THEIR "ULTIMATE SIN" .. THE PREGNANCY IS REFERRED TO IN 4:1 .. OR DOES 4 COME BEFORE 3???
MORONS
2006-11-10 12:18:16
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answer #1
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answered by Jason V 2
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The deformities in genetic structure are not only from the illnesses, pollution, drugs and radiation that you might have had during your life, but from a damaged genetic structure passed down from ancestors. These damaged genes are usually recessive, but if you were to get the same gene from both parents, the defective gene could cause problems. Adam and Eve had no earthly ancestors from which to inherit such problems.
Also, even though they were no longer in the garden, they still lived in a world with no polution. Also their food contained no pesticides, no preservatives, no artificial colors or flavors, and no highly processed ingrediants. In addition, they would have had no drugs.
Starting out with no "family history" problems and the continued pure environment, there would have likely been very few birth difects for many generations.
2006-11-09 06:19:00
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answer #2
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answered by JoeBama 7
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People have a prejudice concept of incest deformities.
Problems ONLY happen after hundreds of years of close blood line inbreeding.
Get enough separatioin between the blood lines and it happens less and less.
The defects we see normally can conceviably be linked (but no one knows conclusively) to the initial inbreeding.
Inbreeding would even occur in the Evolution as delinated by Science since we all came from the first Amoeba.
It is a fact of nature than when a community gets too big, it moves away and forms another cell elsewhere.
Tribalism can't work in a city structure.
Tribalism counts on the ENTIRE collective to participate and whe you have a city of 500,000 you can't know everyone's name.
Tribes dispearse, 2nd cousins marry, they move off, then at meetings 3rd cousins marry, they move off.
Eventually the father's blood line is lost to the son's or the grandsons or the greatgrandson's.
There are 40 chromosome possiblities in each female over her lifetime and millions in each male for each mating.
2006-11-09 06:08:18
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answer #3
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answered by Anonymous
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Amy the tree of knowledge was an example of the law that was to come. The tree of life was an example of grace which was also yet to come. The law did not come to man until Moses. Where there was no law there was no sin. The world has become more filled with disease as iniquity increased. Many people who live prior to Noah lived 900 years therefore even considering that brothers married sisters there were generations of children of Adam and his descendants to choose from not simply direct brothers and sisters.Consider how many children Adam might have had in 900 years and how many children his children and grand children and great grand children may have had ..entire civilizations were built over these generations.
2006-11-09 06:07:10
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answer #4
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answered by djmantx 7
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Their bodies did not instantly grow old and die. They lived for hundreds of years after they were expelled from Eden. They were still in a semi-perfect state and thus their children would have been born without the imperfect genetics we are born with now. Incest was allowed for a time, in order that God's purpose to "fill the earth" was accomplished. God knew that as time went on, humans would not be able to have that kind of relationship without harmful consequences, so he then forbid incest and it is still forbidden for Christians to engage in it today.
2006-11-09 06:21:45
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answer #5
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answered by Micah 6
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If the first two people were both male, it would make the bible even more absurd. God didn't write the bible, men wrote the bible, and it was all politically correct for the day. With Adam and Eve we are all a bunch or inbreds as it is, but with Adam and Steve, umm yeah, unless Steve had a womb, which negates the gay rights activists point.
2016-05-22 00:45:23
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answer #6
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answered by ? 4
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Genetically they wer pure so there wouldn't have been the variations or mutations in their genes that we see now which would cause physical and mental issues in children. You see later in the OT where God bans incest because at that point the gene pool had become tainted and it was no longer a viable option.
2006-11-09 06:38:52
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answer #7
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answered by Bruce Leroy - The Last Dragon 3
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Why can't you people stop mixing up religion and science?
All religion is based on myth, which you are supposed to believe in literally and which is not supposed to change.
The story of Adam and Eve is only one of many creation myths, nothing to do with reality.
Science is a system that is supposed to be constantly open to doubt and new knowledge/hypotheses/theorems, and refuses to speculate on the supernatural, because it is outside its realm.
And never the twain shall meet.
2006-11-09 06:14:48
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answer #8
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answered by Anonymous
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well first off it doesent matter how perfect the original people were, there still isnt enough DNA to get so many different people. after a certain amount of generations inbreeding would show. and its not that many either.
most biological anomolies arent caused by genetics, theyre caused by things that happen during the development of the fetus. so our DNA or Genes have nothing to do with the anomolies that some might see.
i htink you need to go back to school, or at least take a critical thinking class.
2006-11-09 06:00:19
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answer #9
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answered by johnny_zondo 6
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Adam and Eve are "material sons" not born on this world. They came here to be biological uplifters to the already existing races. They went into default , but they still managed to bring much progress to this world.
Urantia Book P 821.
2006-11-09 06:04:39
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answer #10
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answered by samssculptures 5
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Never underestimate the ability of the theist to rationalize without proof in order to protect their beliefs. That "perfect DNA" thing always makes me laugh. Every time.
2006-11-09 06:24:37
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answer #11
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answered by Anonymous
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