h****n
发帖数: 2552 | 1 【 以下文字转载自 Biology 讨论区 】
发信人: midwestPstD (中西部博士后), 信区: Biology
标 题: 请教CRISPR行家-HDR Template Design
发信站: BBS 未名空间站 (Tue Nov 18 16:24:10 2014, 美东)
看了Zhang Feng的Nature Protocol关于CRISPR的文章，Figure 6里面的ssDNA
template明显的效率比plasmid作template高。文章并没有明确说明哪个template好。
想了一下，ssDNA分子量比plasmid小多了，同样的ug template, ssDNA的分子数肯定多
多了，也许这是一个解释。
我自己在设计HDR template，想两边各一个Kb的homologous arm,中间有60-70bp 的
mutation insertion。这个两kb的DNA准备克隆到一个plasmid里面，sequencing确定
mutation后，就可以用作HDR template了。
想请教的是：需要把这个两Kb的template从plasmid里... 阅读全帖 |
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k***r
发帖数: 13724 | 2 你问反了，是旧大陆的猴子变异出的特性而已，有优势可以从绿叶中找出红果子，还能
分辨出发情的母猴子。
It is generally assumed that the ancestors of all monkeys were prosimians
who were monochromatic or dichromatic. The Old and New World monkeys became
separated 30-40 million years ago and have been traveling down their own
evolutionary tracks since then. It is likely that mutations in the X
chromosome gene or genes that provide the ability to see red colors occurred
after this separation. Given that trichromacy occurs in both the New and
Old W... 阅读全帖 |
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c**i
发帖数: 6973 | 3 (1) You say, "现在在国内."
Sorry, there is NOTHING anybody can do, now that the patient--er, the dog--
is in China. Say what you may, but China is no place to treat human or
animal patients.
(2) Jack Daniel Terrier
http://en.wikipedia.org/wiki/Jack_Russell_Terrier
(Originating in the early 19th century from dogs bred and used by Reverend
John Russell, it has similar origins to the modern Fox terrier)
(3) Google with the term (Jack Daniel Terrier spine)--not quotation marks--
and you will find many ow... 阅读全帖 |
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s********7
发帖数: 404 | 4 楼主什么意思？
是不是吃了苏丹红地沟油牛尿奶、呼吸着PM2.5超标空气、喝着TVOC高企的水的国男们
，想生孩子都要慎重？
最荒谬的是“因为卵子是女人还在胎儿时就产生，所以老化迹象不明显。”
事实恰恰相反，卵子最容易老化，原因在于卵子的老化是形成后的老化，而不是形成中
mutation errors所致的老化。
正如楼主所言，mutation errors16年才翻一番，不是翻16番！这个倍数和它本身很低
的基数，对于精子质量的影响来说，根本微不足道。
最关键的是，精子是海量的，健康的卵子本身有一种精密的择优机制：只选择健康的精
子受精。即便是18岁的男子，每次排出的也是有很多有缺陷的精子的。
我在另一个场合论述过，事实上，在不考虑健康因素时，相对高龄的父亲，比年轻的父
亲，能够带来更聪明、更有社会竞争力的子女。
而子女的先天健康，主要受母亲的基因（和健康）的影响。
“在生养这个问题上，男女（年龄）是半斤八两” 这样的结论，无论是从生物学医学
的角度，还是社会实践的角度，都是错误的。
古代和现代医学早已证实，男子比女子大7岁左右的婚姻，生育的子女最优，对孕母也
是最佳的。
抓到一些貌似... 阅读全帖 |
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V****n
发帖数: 651 | 5 大龄父母对生小孩都不好，这是常识。女性生育期短于男性，同样40岁，女性已接近生
育晚期，男性一般还有二十年，这也是常识。至于同样40岁，女性和男性生育带来的危
险系数哪个大，大多少，现在不能定量，将来迟早是可以的。
自然的这篇文章研究的只是关于autism和精神病的snp突变比例，大龄男性比年轻男性
突变多些，没什么奇怪。大部份的snp对人体都无害。需要注意的是，每个人继承的30
亿个碱基对里都有数百个左右的unique的snp变异，对身体有什么影响，目前还没有能
力研究，但这是personalized medicine研究的理论基础。自然文章提到的相关snp变异
数量为55，绝大部份对小孩没有影响，少数对autism和精神病的影响，文章也提到，只
是可能，不是证明“The study does not prove that older fathers are more
likely than younger ones to pass on disease-associated or other deleterious
genes, but that is the strong imp... 阅读全帖 |
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B********e
发帖数: 19317 | 6 http://evolution.berkeley.edu/evolibrary/article/0_0_0/evo_16
Mechanisms of change
Each of these four processes is a basic mechanism of evolutionary change.
Mutation
A mutation could cause parents with genes for bright green coloration to
have offspring with a gene for brown coloration. That would make the genes
for brown beetles more frequent in the population.
Migration
Some individuals from a population of brown beetles might have joined a
population of green beetles. That would make the gene |
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D*****r
发帖数: 6791 | 7 The random direction in mutation and natural selection is consistent with
human knowledge and experiments(e.g. Mendel's experiments on peas which is a
good representation of what happened in the wild). It relies on the
assumption that there is no divine intervention since there is no reliable
evidence of divine intervention.
Why do you need a divine intervention anyway? Cann't you accept the natural
explanation of how water turns into ice in winter?
Unless you see evidences of divine interventio... 阅读全帖 |
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D*****r
发帖数: 6791 | 8 The random direction in mutation and natural selection is consistent with
human knowledge and experiments(e.g. Mendel's experiments on peas which is a
good representation of what happened in the wild). It relies on the
assumption that there is no divine intervention since there is no reliable
evidence of divine intervention.
Why do you need a divine intervention anyway? Cann't you accept the natural
explanation of how water turns into ice in winter?
Unless you see evidences of divine interventio... 阅读全帖 |
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l**********t
发帖数: 5754 | 9 again, assuptions are personal tastes, subjective and can't be proved.
---sorry for the parody---
The intervention/guidance in mutation and "natural selection" is consistent
with
human knowledge and experiments. It relies on the assumption that in general, randomness leads to
chaos/lack of order & complexity/increase in entropy, since there is no
reliable evidence of such observation in our daily life with high
probability.
Why do you need a random assumption anyway? Can't you accept the fact th... 阅读全帖 |
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l**********t
发帖数: 5754 | 10
the Preservation of Favoured Races in the Struggle for Life
Charles Darwin
The theory (gradual evolution thru random mutation and natrual selection
based on advantages from the mutation) can not explain the complexity of
even a simple biological system (like virus, let alone mammals), the
complexity that only recentrly (since the discover of DNA in 50s) revealed
thru biological researches at the molecular level.
IMHO, all these studies just reveal the details of the wonder of God's creation gra... 阅读全帖 |
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D*****r
发帖数: 6791 | 11 Evolution is a historical science. Not being able to be repeated does not
mean it is not true. This is the same as detectives can infer what must have
happened even though they cannot repeat the crime.
It can also be tested. The search for new fossils can always be predicted
and verified by the theory. And evolution is so well tested that it is used
as a fact to determine the age of the soil and rock near the fossil.
Creationism can explain everything so it explains nothing. It needs infinite
ex... 阅读全帖 |
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l**********t
发帖数: 5754 | 12 actually the impact of each individual mutation is "neutral" -- based on our
current understanding of a mutation's impact on biological funtions |
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T*******r
发帖数: 333 | 13
around
to
你的意思就是基督徒在这个公共版面可以恣意传播进化论的谎言，而飞机不能反驳。是
这个意思吗？
真奇怪，为什么基督徒到了说不过去的时候自觉不自觉的就想要封人之口，不让人说话
呢？
：ages. But that doesn't apply in Darwin's evolution theory in the
：explaination of pre-historic orgin of species.
再说一遍，在细菌抗药性变异的过程中没有“targeted mutation”，完全是细菌自发
的变异并经过自然选择导致耐药性的增加。这是关键的一点，我再强调一遍。不要再这
个问题上试图搞混水。如果人类可以“targeted mutation”细菌，为什么不能把细菌
改的更容易被抗生素杀死？为什么偏偏要反其道而行之，限制自己的抗生素使用？
还是那句话，不要转移话题。“进化论能不能预测”和“进化论能不能解释史前生物的
起源”是两个不同的话题，需要不同的证据。你要讨论后者请另起一个话题。
但是现在，我再问你一遍（最后一遍），“细菌耐药性变异”是不是进化论的预测？
如果你还是... 阅读全帖 |
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d******2
发帖数: 107 | 14 1) We might be able to analyze littletshirts' refutation of evolution for
this "random" assumption by reviewing the anthropic principle(人择原理). I
think it can be applied here. Certain mutations have to happen for the Homo
sapiens to evolve. But that doesn't mean mutations have a guidance or
are intervened by divine objects.
Say you are playing cards. Cards are shuffled and randomly distributed to
players. When we see the cards played by a player, we can get an idea of
what cards the player has. W... 阅读全帖 |
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E*****m
发帖数: 25615 | 15 mutation mutation
but
related |
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E*****m
发帖数: 25615 | 17
based
the
Let me put it this way. The degree I doubt evolution is about the
same as you doubt the earth is not flat.
What healthy skepticism do you have on earth's shape? Please do
tell us.
Could you make it more clear? You don't believe mutation is random,
or you don't believe there is any mutation? |
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E*****m
发帖数: 25615 | 18
I've asked you many times, never got an answer.
You don't believe there is mutation, or you don't believe
mutation is random? Why is this so hard for you to answer? |
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l**********t
发帖数: 5754 | 19 Great. we finally reached agreement on the key point. IMHO, the "evolution
theory" science is silent on the root cause of the variations ( " not
knowing the cause of the random mutations...."), and thus describe them as "
random" (to represent changes due to intractable/unknown cause by chance, regardless how low the probability is). There is
nothing wrong with it but you have to acknowledge the unknown causes.
And I believe God is the root cause for these changes (via meanings beyond
my underst... 阅读全帖 |
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D*****r
发帖数: 6791 | 20 Stephen C Stearns在耶鲁的进化论与生态学课程的第6讲
http://www.youtube.com/watch?v=ZzkLYZCzHXk
The Origin and Maintenance of Genetic Variation
Overview:
Mutations are the origin of genetic diversity. Mutations introduce new
traits, while selection eliminates most of the reproductively unsuccessful
traits. Sexual recombination of alleles can also account for much of the
genetic diversity in sexual species. In some instances, population size can
affect diversity and rates of evolution and fixation, but in other ca... 阅读全帖 |
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E*****m
发帖数: 25615 | 21 有人比我慘嗎？50 多篇！
2 -0.10 [TrustInJesus版]的标题为[破解耶穌山頂寶訓 (二) 耶穌要人不怕
被人當惡人]的文章被删除 2011-06-26 19:22:39
3 -0.10 [TrustInJesus版]的标题为[破解耶穌山頂寶訓 (一) 耶穌開頭說的
是xxxx]的文章被删除 2011-06-26 19:22:33
4 -0.10 [TrustInJesus版]的标题为[解釋（哥德爾版）本體論證明上帝存在]
的文章被删除 2011-06-26 19:22:26
5 -0.10 [TrustInJesus版]的标题为[基督徒的潛規則(五) 耶和華<耶穌<保羅
<自己]的文章被删除 2011-06-26 19:22:09
6 -0.10 [TrustInJesus版]的标题为[神樂意看到大家吵神學問題]的文章被删
除 2011-06-26 19:21:52
7 -0.10 ... 阅读全帖 |
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l**********t
发帖数: 5754 | 22
please do not 轉移話題 ---
Just cite ONE example with detailed root causes & mechanics to explain
evolution without using random mutation as an excuse.
If you cannot, just acknowledge that the "evolution theory" is based on the
"random" (unknown cause) mutation assumption, which is the only key difference between "
evolution theory" and Christian belief IMHO. |
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l**********t
发帖数: 5754 | 23
exactly, ONE of the many possibilities.
don't confuse a computer algorithm with natural science. The algorithm will
do whatever you design it to do, and if implemented successfully, it will
achieve what you set it to achieve. It has nothing to do with what happens
in nature and can't serve as a proof. Plus, an intl-design advocate could claim that God designs the algorithm and optimized the parameters in nature to guide the "evolution".
the evdiences are consistent with various assumptions -- ... 阅读全帖 |
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m*******y
发帖数: 148 | 24 that's only an evidence of the possibility of evolution. that is, it is
possible to generate complex, stable systems from simpler ones with random
mutations and natural selection. not to prove evolutionary theory itself.
although in this case I coded the program, it does not mean that there has
to be a designer. mutation and cross-over rules could be natural laws, while
parameters are selected randomly anyway.
so, |
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h****9
发帖数: 1087 | 25 I am not talking about random mutation, I am talking about 随机变异进化, a
successful mutation that is stable and can be passed to the next generation.
divine
to |
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c******r
发帖数: 889 | 26 Random和spontaneous很多时候是为了是问题叙述讨论简单而用。
具体context下，含义不一样。
比如常说random mutation, 是指发生的具体site不好具体预测。并不是说不知道这个
变异发生的具体原因。比如紫外线光照引起的很特定的化学反应什么的。
Chromosomal fusion, translocation...很多变异的机理都比较清楚了，但是我们还说
random mutation, 因为他可以发生在genome里任意点。
进化很多具体细节还没搞清楚。但是，已有证据，已经能够证明进化是事实。
生物学界是这样的共识，当然，不是每一个。
广义的”神“，如果你认为有那么一个，无法证实也无法证伪，愿意加一个theistic-
的前缀，那是你的自由，但那就已经不是科学理论了，而是一个观点。
至于圣经记载，那就是另一种情形，是和我们已知事实充满了矛盾。
excuse |
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l**********t
发帖数: 5754 | 27
Thanks.
And you believe that the well balanced, complex pathways that regulate cell
cycle (say expression of p53) are outcome of a sequences of random physical/
chemical reactions thru "evolution" -what's the probability of it?
How often do you see a mutation that creates brand new genes to cause cancer? I bet most of the time the random mutations are destructive to the existing system. |
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c****g
发帖数: 3893 | 28 sequential mutation 不是你讲的那个东西吧？
new
the
mutations are independent. |
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B******y
发帖数: 2255 | 29 看了下。
尼龙菌的移码突变T是由其自身一个质粒插入的，所以必须证明这个插入不是该机体生
命机能的一个intrinsic function，而是一个意外。
因为生命机能的内在功能里有修改自己遗传密码的部分以达到适应外界变化的例子，比
如人体的免疫系统B细胞，能辨认理论上的几乎任何蛋白质，其辨认过程就是靠自动自
发的DNA mutation,其mutation有固定的process,类似一种分子算法。辨认抗原编码新
抗体的过程就是机体的分子计算过程。
可以看一下下面链接的V(D)J recombination，和Somatic hypermutation and
affinity maturation两个部分。对B细胞，后者就是其B细胞自身在遗传（分裂中）改
变自身DNA某个设定区域的编码，这是其特定功能的部分。
http://en.wikipedia.org/wiki/Antibody
所以那个尼龙菌必须排除这种生命的内在机制，才可以说是一种新细菌。
其实验证这个比较容易，只要把尼龙菌放入前身细菌的常见生活环境看其是否可能还原
成前身细菌，就可以验证。 |
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l**********t
发帖数: 5754 | 30
sounds like the faith in "random mutation and natural selection". Any
unexplainable changes is attributed to "random" mutation and any order out
of chaos is credited to "natural selection" --but only after the fact. It
surely "explains" the creation of life nicely.说什么都行了 |
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s*y
发帖数: 933 | 31 Wrong, your reasoning is not sound. You are trying to fit for an answer
after the fact. First of all, creation does not predict that a creator must
use common building blocks/materials to create various species. Second, no
text in Bible supports common building blocks/materials anyway. In fact,
one would expect, if there is a 全能的 God, that he would create life use
many different building blocks/materials. This would show his awesome power
that he is not limited to one material, and would ce... 阅读全帖 |
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l**********t
发帖数: 5754 | 32 you believe in "random mutation/natural selection" anyway even w/o proof
that mutations are random/spontaneous. You simply take that as granted. |
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G******e
发帖数: 9567 | 33
After lots of critical thinking, you can tell the difference between "
mutation" vs "random" is that "mutation" is not "random", right? |
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l**********t
发帖数: 5754 | 34
because it is faith vs. assumption.
that's incorrect. you can produce whatever mutation in the lab, but these
are not the unique mutations that lead to the unique events in the sequence
of events that lead to the life/human appearance (not to mention the unique
environment states that enforce the "natural selection")
again, you observed these OUTCOMES and the underlying mechanics is
attributed to uncertainty in theromal dynamics.
"不管这些variation最初是怎么形成的" -- I think 不管这些variation最初是怎么形
成的 is the... 阅读全帖 |
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I****2
发帖数: 1091 | 35 http://www.newscientist.com/article/dn14094-bacteria-make-major
Lenski's experiment is also yet another poke in the eye for anti-
evolutionists, notes Jerry Coyne, an evolutionary biologist at the
University of Chicago. "The thing I like most is it says you can get these
complex traits evolving by a combination of unlikely events," he says. "That
's just what creationists say can't happen."
http://phys.org/news104764947.html
How bacteria evolve into superbugs
Researchers at McGill and Oxford Uni... 阅读全帖 |
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b*********n
发帖数: 1607 | 36 有人举例病毒变异的例子作为进化论的实验证据。那么就讨论一下了。进化的内在根本
是基因突变，是意外突变，而不是原有设计好的固有功能。但是生命体确实有内在功能
里有修改自己遗传密码的部分以达到适应外界变化的例子，比如人体的免疫系统B细胞
，能辨认理论上的几乎任何蛋白质，其辨认过程就是靠自动自
发的DNA mutation,其mutation有固定的process,类似一种分子算法。辨认抗原编码新
抗体的过程就是机体的分子计算过程。
所以必须确定一个基因变化是生命体内在功能的表现，还是一个意外的突变。如果是前
者，那不是进化；只有后者才是进化。
所以不能只看到一篇泛泛的论述说基因不一样了，有了抗性了，就说这是进化。这不够
的。必须在更多的试验研究确认这种变化不是病毒内在的功能机制，在生存环境变化后
，启动了这部分功能。
圣经里记载雅各和以扫是同父同母的双胞胎兄弟。但是雅各皮肤光滑，以扫全身长毛。
难道圣经里宣扬进化论吗？显然不是。这正好说明了人类固有功能中就有产生多毛基因
的能力。 |
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l**********t
发帖数: 5754 | 37
it makes all the difference.
site-target mutation is by design, and "random" mutation is by chance and
implicitly or explicitly exclude God from the creation process. |
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i******e
发帖数: 217 | 38 你总是没话说了就要mutation
以后这样吧，你觉得自己没道理了就说“我要mutation了”
大家也就不逼你了 |
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l**********t
发帖数: 5754 | 39 :【 在 littletshirt (苹安喜乐) 的大作中提到: 】
：我在回答 random mutation， 這還不夠明顯嗎？
我去年问你"random" 的定义，（你现在说当时）你回答的是"mutation"的定义. 原因
夠明顯。 |
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E*****m
发帖数: 25615 | 40 當初討論時她問我 random 是啥意思， 在那上下文中我認為她問的是
random mutation 是什麼意思， 結果她抓到這點問題沒完沒了，
她不是真以為會有人搞不清楚 random 和 mutation 兩個完全不同
詞性的字， 就是找不到其他可以講就裝傻。
對於這麼扯皮的人，老實講我還真不知道有什麼可以討論的， 問她
十幾次讀過什麼進化論書， 每次都裝看不見。 |
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l**********t
发帖数: 5754 | 41 Thanks for confirming that "evolution theory" does NOT answer the question
on the origin of life.
As to the 2nd question, do you agree that the driving forces of "evolution"
(the cause of mutation & the state of the overall environment for natural
selection) are
exogenous to the "evolution theory" itself (out of the scope of the theory
as you put it earlier), and the outcome are thus non-deterministic within
the theory?
发信人: Eloihim (真神), 信区: TrustInJesus
标 题: Re: 关于眼睛结构的智创论[zz]
发信站: BBS 未名空间站... 阅读全帖 |
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b********g
发帖数: 2156 | 42 CCR5-D32，基因突变造成的,并不是应对hiv的基因进化。这种基因突变造成细胞膜表面
receptor损伤。原本是不好的事情，却恰巧损害到hiv的binding site，因为病毒都是
bind在特定的receptor上才能进入host cell，所以hiv就不能攻击了。目前的理论是说，
这种基因突变是variola virus，造成smallpox的病毒引起的。
Up to 20% of ethnic western Europeans carry this mutation, which is rare or
absent in other ethnic groups.9–11 This suggests that the CCR5-delta32
mutation was strongly selected for sometime during European history. Some
researchers have proposed that the plague epidemics that repeatedly swept
Europe during the M... 阅读全帖 |
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b********g
发帖数: 2156 | 43 ApoA-1 Milano是蛋白质变异，不是基因。研究发现，这种蛋白质颗粒对血管粥样硬化
有效果。
Discovered by accident, the mutation was found to be present in about 3.5%
of the population of Limone sul Garda, a small village in northern Italy. It
has been traced to a mutation in a single man, Giovanni Pomarelli,[2] who
lived in the village in the 18th century and passed it on to his offspring.[
3] |
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t*******d
发帖数: 2570 | 44 其实littleshirt一直在做的就是钻"Random"这个词的不同意义的空子。
进化论里面的"Random Mutation"的意思是跟"Directed Mutation"相对的。指的是突变
的方向跟让生物存活下来的方向是不一致的。这个意义上的“Random"是不用依靠faith
来解决的。有很经典的实验证明了这一点。
但是"Random"还有别的意思，另一个意思可以是“没有任何规律可循”。 这个意义上
的”Random"是需要依靠faith的。毕竟科学上没法绝对证明什么东西没有任何规律可循。
进化论里用的"Random“是第一种定义，littleshirt偏要说人家进化论用的是第二种定
义。这其实也是打稻草人的一种方法。 |
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l**********t
发帖数: 5754 | 45
you are confused about the root-cause of changes with outcome distribution
of changes.
造成新物种的新基因形成的原因才是问题的关键。你认为新基因形成的原因是"
spontaneous"的吗？ how do you prove something is spontaneous?
另外你说的“random mutation"的试验， 和新基因形成的原因没关系。
比如，你可以试验观察证明一段有功能的编码信息 （DNA /书/无线信号，等）复制过
程中的信息衰减变化后的noise是random分布的。 但这不能证明原来有功能的编码信息
是从random noise形成来的。
终于有学过进化论的评论了．这可是打了本版进化论民科“领袖”的脸：
同意：科学上没法绝对证明 "spontaneous random mutation＂ |
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t*******d
发帖数: 2570 | 46 你搞错了。E神很清楚的表明他不介意这个所谓的Random mutation是不是真的毫无规律。
这跟我说的其实是一样的。进化论表述中的Random mutation不代表绝对的无序。
不过你搞错也不是一两回了。不知道是你真的不知道还是故意如此。
evlution |
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l**********t
发帖数: 5754 | 47
律。
你搞错了. 你介意不介意 mutations are not spontaneous but intelligently
designed and targeted (directed)? If you don't care, you shall agree with
intel-design theory.
You shall read what I replied to your original comment.
Lao E (and you) keep evading the key question: whetehr the mutations are
spontaneous, and if so, how do you prove it is spontaneous. If you can't
prove the unprovable, then just acknowledge that, instead of evading the
answer.
So you do agree with lao E's following statement? Y/N? If... 阅读全帖 |
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l**********t
发帖数: 5754 | 48
None of them prove mutations are spontaneous. If not sure, check with your "
expert" buddy theislander.
And all of them are also consistent with intel-desng (mutations are not
spontaneous).
Which one you choose (spontaneous or non-spontaneous) is a belief. |
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t*******d
发帖数: 2570 | 49 按照你给的spontaneous的定义，evolutionary theory 不需要mutation 是你说的这种
spontaneous.
不过按照spontaneous在进化论框架下的定义，evolutionary theory 是需要 mutation
是spontaneous的。
你对的spontaneous的定义跟进化论框架下spontaneous定义的不同会导致我对你的问题
的回答的不同。
evade |
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