قناة "أنتي-دارويني مـوحد" ..

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  • _aMiNe_
    طالب علم
    • Jul 2007
    • 1528

    #16
    أتمنى من الملاحدة ضبط النفس قليلا .. و لا داعي لقلة الأدب و السفالة التي لا نعجب من صدورها عن من دينه الإلحاد !

    فليتألم من أراد .. و لكن بدون صراخ بذيئ !

    الموضوع لا زال في بدايته .. و الفيديوهات الأولى ما هي إلا تسخينات ..

    الفيديو القادم سيكون حول المستر داوكينز .. و لكن بعد فترة انقطاع بسب بعض الظروف.

    و، إن شاء الله، .. القافلة تسير .. ..

    شكرا للإخوة الداعمين للقناة ..

    مع التحية.

    أحب الصالحين ولست منهم ** لعلي أن أنال بهم شفاعة
    و أكره من تجارته المعاصي ** و لو كنا سواء في البضاعة
    تغيُّب ..

    Comment

    • _aMiNe_
      طالب علم
      • Jul 2007
      • 1528

      #17
      ملاحظة : الإساءة لم تصدر عن ملاحدة المنتدى ..

      أحب الصالحين ولست منهم ** لعلي أن أنال بهم شفاعة
      و أكره من تجارته المعاصي ** و لو كنا سواء في البضاعة
      تغيُّب ..

      Comment

      • Light
        عضو
        • Apr 2010
        • 587

        #18
        أخي أمين . هل يمكنك ان تضع ذلك المقطع الذي يسأل فيه داوكنز عن مثال للطفرة الموجبة ثم لم يستطع , أعتقد ان هذا المقطع الصغير له دلالة كبيرة جدا و الله أعلم

        Comment

        • _aMiNe_
          طالب علم
          • Jul 2007
          • 1528

          #19
          و ارتدَّ عن الداروينية .. !!


          أحب الصالحين ولست منهم ** لعلي أن أنال بهم شفاعة
          و أكره من تجارته المعاصي ** و لو كنا سواء في البضاعة
          تغيُّب ..

          Comment

          • _aMiNe_
            طالب علم
            • Jul 2007
            • 1528

            #20
            الفيديو القادم سيكون حول المستر داوكينز .. و لكن بعد فترة انقطاع بسب بعض الظروف.
            قريبا إن شاء الله ..

            أحب الصالحين ولست منهم ** لعلي أن أنال بهم شفاعة
            و أكره من تجارته المعاصي ** و لو كنا سواء في البضاعة
            تغيُّب ..

            Comment

            • mokraki
              عضو
              • Apr 2010
              • 203

              #21
              السلام عليكم
              أخي أمين هل بإمكانك أن تضع
              فيديوهات توضح القمع والسياسة الديكتاتورية المتبعة لفرض
              الداروينية
              إنّ رجال الدين في القرون الوسطى، ونتيجةً للجهل أو التعصّب، قد رسموا لدين محمدٍ صورةً قاتمةً، لقد كانوا يعتبرونه عدوًّا للمسيحية، لكنّني اطّلعت على أمر هذا الرجل، فوجدته أعجوبةً خارقةً، وتوصلت إلى أنّه لم يكن عدوًّا للمسيحية، بل يجب أنْ يسمّى منقذ البشرية، وفي رأيي أنّه لو تولّى أمر العالم اليوم، لوفّق في حلّ مشكلاتنا بما يؤمن السلام والسعادة التي يرنو البشر إليها.
              برنارد شو

              Comment

              • نور الدين الدمشقي
                طالب علم
                • Jul 2010
                • 2207

                #22
                جزاك الله خيرا اخي أمين. ولن يكفي مدحي لجهودك المشكورة فانت لا تحتاج مثله من مثلي.
                ولي بعض التعليقات على فيديو: "رأي البروفيسور مايكل دنتون".
                لعلك قد اطلت في عرض اللوحة الأولى والثانية. ولعلك تضيف اليها بعض المؤثرات الصوتية في الخلفية...نشيد اسلامي مثلا.
                كذلك لعلك تكبر الخط قليلا كي تسهل قراءته.
                وبارك الله فيكم.
                "العبد يسير إلى اللـه بين مطالعة المنة ومشاهدة التقصير!" ابن القيم
                "عندما يمشي المرؤ على خطى الأنبياء في العفاف, يرى من نفسه القوة والعزة والكبرياء. بينما يعلم المتلوث بدنس الفحش الضعف من نفسه والضعة والتساقط أمام الشهوات"

                Comment

                • _aMiNe_
                  طالب علم
                  • Jul 2007
                  • 1528

                  #23
                  السلام عليكم و رحمة الله و بركاته،
                  أخي "mokraki" إن شاء الله يمكن الاستفادة من تلك النقطة .. و لكن بعد تحليل المواد التي سلطت عليها الضوء ..
                  حياك الله.

                  أخي "strenger" بارك الله فيك أخي الكريم على ملاحظاتك .. و إن شاء الله أستفيد منها ..
                  و بالنسبة لمسألة المؤثرات الصوتية فأنا متردد في هذا .. نظرا للسياق .. و في انتظار آراء باقي الإخوة بهذا الخصوص.
                  و بالطبع الشكر لا أستحقه لا للسبب الذي قلته (و الذي عكسه هو الصحيح)، و لكن لأنني لم أقم، فعلا، بما يستحق الشكر ..

                  جزاكم الله خيرا ..

                  أحب الصالحين ولست منهم ** لعلي أن أنال بهم شفاعة
                  و أكره من تجارته المعاصي ** و لو كنا سواء في البضاعة
                  تغيُّب ..

                  Comment

                  • يحيى
                    عضو
                    • Oct 2007
                    • 1280

                    #24
                    بارك الله فيك اخي امين
                    ما هو البرنامج الذي تستخدمه لاضافة التعليقات العنواين الفرعية (Sous-titres)؟
                    الفلسفة الإنسانية أو علمنة الفلسفة و العلم وراء الكارثة الحديثة التي تسبب اللاوعي و الإحباط كنتيجة للصراع بين المتناقضات, فعلى سبيل المثال لا الحصر, تصور الحياة على أنها عبثية -أو نتيجة عملية عبثية- من جهة, و من جهة ثانية إبعاد صفة العبث عن هذا التصور و عن أي محاولة فلسفية فكرية متتالية في إثبات هذا التصور!!

                    Comment

                    • _aMiNe_
                      طالب علم
                      • Jul 2007
                      • 1528

                      #25
                      حياك الله أخي الكريم يحيى ..
                      أستعمل برنامج "SubtitleWorkshop4" لضبط الترجمة مع الوقت ..
                      و برنامج "VirtualDubMod" للصق الترجمة بالفيديو ..

                      أحب الصالحين ولست منهم ** لعلي أن أنال بهم شفاعة
                      و أكره من تجارته المعاصي ** و لو كنا سواء في البضاعة
                      تغيُّب ..

                      Comment

                      • _aMiNe_
                        طالب علم
                        • Jul 2007
                        • 1528

                        #26
                        داوكينز : "ملحد في أزمة" ..!


                        أحب الصالحين ولست منهم ** لعلي أن أنال بهم شفاعة
                        و أكره من تجارته المعاصي ** و لو كنا سواء في البضاعة
                        تغيُّب ..

                        Comment

                        • لينا الكردي
                          عضو
                          • Nov 2010
                          • 1

                          #27



                          كل الروابط على اليوتوب وهي محجوبة في بلدي

                          Comment

                          • عَرَبِيّة
                            طالب علم
                            • Sep 2009
                            • 2039

                            #28
                            بارك الله في الأخ أمين وفي عمره ووقته
                            وزاده علماً وعملاً وجعله من الهادين المهديين

                            أختي لينا الكردي
                            أظن كل موقع الــ " يوتيوب " محجوب في سوريا وليس فقط روابط فيديوهات التوحيد .!
                            أختي جربي .. مشاهد نقية http://www.mashahd.net/
                            إذا فتحت معكِ ربما يُحمّل الإخوة مقاطع فيديوهات منتدى التوحيد على موقع مشاهد وهو موقع إسلامي
                            فتثقيف الفرد المسلم وتحصينه ضد الإلحاد مهم كما هو مهم أن يرى المُلحد تهافت فكره .
                            بارك الله فيكم آل ديني .
                            قال الله سُبحانه وتعالى { بَلْ نَقْذِفُ بِالْحَقِّ عَلَى الْبَاطِلِ فَيَدْمَغُهُ فَإِذَا هُوَ زَاهِقٌ وَلَكُمُ الْوَيْلُ مِمَّا تَصِفُونَ } الأنبياء:18


                            تغيُّب

                            Comment

                            • حسام الدين حامد
                              محاور
                              • Nov 2004
                              • 1868

                              #29
                              المشاركة الأصلية كتبت بواسطة _amine_ مشاهدة المشاركة
                              داوكينز : "ملحد في أزمة" ..!

                              http://www.youtube.com/watch?v=7yihfwwmppm

                              جزاكم الله خيرًا أستاذنا الحبيب ..
                              نِحلة في أزمة!

                              إذا فتحت معكِ ربما يُحمّل الإخوة مقاطع فيديوهات منتدى التوحيد على موقع مشاهد وهو موقع إسلامي
                              فتثقيف الفرد المسلم وتحصينه ضد الإلحاد مهم كما هو مهم أن يرى المُلحد تهافت فكره .
                              اقتراح .. لم لا تقومين أختنا الفاضلة بهذه المهمة بعد التنسيق مع الإدارة، فوقت الإدارة لن يسمح بالنشر في كل المواقع ولا أغلبها.
                              " أَفَمَنْ أَسَّسَ بُنْيَانَهُ عَلَى تَقْوَى مِنَ اللَّهِ وَرِضْوَانٍ خَيْرٌ أَمْ مَنْ أَسَّسَ بُنْيَانَهُ عَلَى شَفَا جُرُفٍ هَارٍ فَانْهَارَ بِهِ فِي نَارِ جَهَنَّمَ وَاللَّهُ لا يَهْدِي الْقَوْمَ الظَّالِمِينَ "
                              صفحتي على الفيسبوك - صفحتي على تويتر.

                              Comment

                              • مراقب 4
                                عضو إدارة
                                • Jan 2005
                                • 982

                                #30
                                هذا تعليق دوكنز على الفيديو، ردًّا على من يدعي أنّه مزيف، أو أنّ السؤال سطحي كما حدث حين وضعت الفيديو على صفحة الفيسبوك، فدوكنز يرى أنّ السؤال المطروح خلافي، وأن إجابات تطوريين من وزن جولد تكون بالنفي، ولكنه يجيب بنعم!

                                in september 1997, i allowed an australian film crew into my
                                house in oxford without realising that their purpose was
                                creationist propaganda. In the course of a suspiciously amateurish
                                interview, they issued a truculent challenge to me to "give an
                                example of a genetic mutation or an evolutionary process which
                                can be seen to increase the information in the genome." it is the
                                kind of question only a creationist would ask in that way, and it
                                was at this point i tumbled to the fact that i had been duped into
                                granting an interview to creationists - a thing i normally don't do,
                                for good reasons. In my anger i refused to discuss the question
                                further, and told them to stop the camera. However, i eventually
                                withdrew my peremptory termination of the interview as a whole.
                                This was solely because they pleaded with me that they had come
                                all the way from australia specifically in order to interview me.
                                Even if this was a considerable exaggeration, it seemed, on
                                reflection, ungenerous to tear up the legal release form and throw
                                them out. I therefore relented.
                                My generosity was rewarded in a fashion that anyone familiar
                                with fundamentalist tactics might have predicted. When i
                                eventually saw the film a year later 1, i found that it had been
                                edited to give the false impression that i was incapable of
                                answering the question about information content 2. In fairness,
                                this may not have been quite as intentionally deceitful as it
                                sounds. You have to understand that these people really believe
                                that their question cannot be answered! Pathetic as it sounds, their
                                entire journey from australia seems to have been a quest to film
                                an evolutionist failing to answer it.
                                With hindsight - given that i had been suckered into admitting
                                them into my house in the first place - it might have been wiser
                                simply to answer the question. But i like to be understood
                                whenever i open my mouth - i have a horror of blinding people
                                with science - and this was not a question that could be answered
                                in a soundbite.
                                first you first have to explain the technical
                                meaning of "information". Then the relevance to evolution, too,
                                is complicated - not really difficult but it takes time. Rather than
                                engage now in further recriminations and disputes about exactly
                                what happened at the time of the interview (for, to be fair, i
                                should say that the australian producer's memory of events seems
                                to differ from mine), i shall try to redress the matter now in
                                constructive fashion by answering the original question, the
                                "information challenge", at adequate length - the sort of length
                                you can achieve in a proper article.
                                Information
                                the technical definition of "information" was introduced by the
                                american engineer claude shannon in 1948. An employee of the
                                bell telephone company, shannon was concerned to measure
                                information as an economic commodity. It is costly to send
                                messages along a telephone line. Much of what passes in a
                                message is not information: It is redundant. You could save
                                money by recoding the message to remove the redundancy.
                                Redundancy was a second technical term introduced by shannon,
                                as the inverse of information. Both definitions were mathematical,
                                but we can convey shannon's intuitive meaning in words.
                                Redundancy is any part of a message that is not informative,
                                either because the recipient already knows it (is not surprised by
                                it) or because it duplicates other parts of the message. In the
                                sentence "rover is a poodle dog", the word "dog" is redundant
                                because "poodle" already tells us that rover is a dog. An
                                economical telegram would omit it, thereby increasing the
                                informative proportion of the message. "arr jfk fri pm pls mt
                                ba cncrd flt" carries the same information as the much longer,
                                but more redundant, "i'll be arriving at john f kennedy airport on
                                friday evening; please meet the british airways concorde flight".
                                Obviously the brief, telegraphic message is cheaper to send
                                (although the recipient may have to work harder to decipher it -
                                redundancy has its virtues if we forget economics). Shannon
                                wanted to find a mathematical way to capture the idea that any
                                message could be broken into the information (which is worth
                                paying for), the redundancy (which can, with economic
                                advantage, be deleted from the message because, in effect, it can
                                be reconstructed by the recipient) and the noise (which is just
                                random rubbish).
                                "it rained in oxford every day this week" carries relatively little
                                information, because the receiver is not surprised by it. On the
                                other hand, "it rained in the sahara desert every day this week"
                                would be a message with high information content, well worth
                                paying extra to send. Shannon wanted to capture this sense of
                                information content as "surprise value". It is related to the other
                                sense - "that which is not duplicated in other parts of the message"
                                - because repetitions lose their power to surprise. Note that
                                shannon's definition of the quantity of information is independent
                                of whether it is true. The measure he came up with was ingenious
                                and intuitively satisfying. Let's estimate, he suggested, the
                                receiver's ignorance or uncertainty before receiving the message,
                                and then compare it with the receiver's remaining ignorance after
                                receiving the message. The quantity of ignorance-reduction is the
                                information content. Shannon's unit of information is the bit, short
                                for "binary digit". One bit is defined as the amount of information
                                needed to halve the receiver's prior uncertainty, however great
                                that prior uncertainty was (mathematical readers will notice that
                                the bit is, therefore, a logarithmic measure).
                                In practice, you first have to find a way of measuring the prior
                                uncertainty - that which is reduced by the information when it
                                comes. For particular kinds of simple message, this is easily done
                                in terms of probabilities. An expectant father watches the
                                caesarian birth of his child through a window into the operating
                                theatre. He can't see any details, so a nurse has agreed to hold up a
                                pink card if it is a girl, blue for a boy. How much information is
                                conveyed when, say, the nurse flourishes the pink card to the
                                delighted father? The answer is one bit - the prior uncertainty is
                                halved. The father knows that a baby of some kind has been born,
                                so his uncertainty amounts to just two possibilities - boy and girl -
                                and they are (for purposes of this discussion) equal. The pink card
                                halves the father's prior uncertainty from two possibilities to one
                                (girl). If there'd been no pink card but a doctor had walked out of
                                the operating theatre, shook the father's hand and said
                                "congratulations old chap, i'm delighted to be the first to tell you
                                that you have a daughter", the information conveyed by the 17
                                word message would still be only one bit.
                                Computer information
                                computer information is held in a sequence of noughts and ones.
                                There are only two possibilities, so each 0 or 1 can hold one bit.
                                The memory capacity of a computer, or the storage capacity of a
                                disc or tape, is often measured in bits, and this is the total number
                                of 0s or 1s that it can hold. For some purposes, more convenient
                                units of measurement are the byte (8 bits), the kilobyte (1000
                                bytes or 8000 bits), the megabyte (a million bytes or 8 million
                                bits) or the gigabyte (1000 million bytes or 8000 million bits).
                                Notice that these figures refer to the total available capacity. This
                                is the maximum quantity of information that the device is capable
                                of storing. The actual amount of information stored is something
                                else. The capacity of my hard disc happens to be 4.2 gigabytes. Of
                                this, about 1.4 gigabytes are actually being used to store data at
                                present. But even this is not the true information content of the
                                disc in shannon's sense. The true information content is smaller,
                                because the information could be more economically stored. You
                                can get some idea of the true information content by using one of
                                those ingenious compression programs like "stuffit". Stuffit looks
                                for redundancy in the sequence of 0s and 1s, and removes a hefty
                                proportion of it by recoding - stripping out internal predictability.
                                Maximum information content would be achieved (probably
                                never in practice) only if every 1 or 0 surprised us equally. Before
                                data is transmitted in bulk around the internet, it is routinely
                                compressed to reduce redundancy.
                                That's good economics. But on the other hand it is also a good
                                idea to keep some redundancy in messages, to help correct errors.
                                In a message that is totally free of redundancy, after there's been
                                an error there is no means of reconstructing what was intended.
                                Computer codes often incorporate deliberately redundant "parity
                                bits" to aid in error detection. Dna, too, has various errorcorrecting
                                procedures which depend upon redundancy. When i
                                come on to talk of genomes, i'll return to the three-way distinction
                                between total information capacity, information capacity actually
                                used, and true information content.
                                It was shannon's insight that information of any kind, no matter
                                what it means, no matter whether it is true or false, and no matter
                                by what physical medium it is carried, can be measured in bits,
                                and is translatable into any other medium of information. The
                                great biologist j b s haldane used shannon's theory to compute
                                the number of bits of information conveyed by a worker bee to her
                                hivemates when she "dances" the location of a food source (about
                                3 bits to tell about the direction of the food and another 3 bits for
                                the distance of the food). In the same units, i recently calculated
                                that i'd need to set aside 120 megabits of laptop computer memory
                                to store the triumphal opening chords of richard strauss's "also
                                sprach zarathustra" (the "2001" theme) which i wanted to play in
                                the middle of a lecture about evolution. Shannon's economics
                                enable you to calculate how much modem time it'll cost you to email
                                the complete text of a book to a publisher in another land.
                                Fifty years after shannon, the idea of information as a commodity,
                                as measurable and interconvertible as money or energy, has come
                                into its own.
                                Dna information
                                dna carries information in a very computer-like way, and we can
                                measure the genome's capacity in bits too, if we wish. Dna
                                doesn't use a binary code, but a quaternary one. Whereas the unit
                                of information in the computer is a 1 or a 0, the unit in dna can
                                be t, a, c or g. If i tell you that a particular location in a dna
                                sequence is a t, how much information is conveyed from me to
                                you? Begin by measuring the prior uncertainty. How many
                                possibilities are open before the message "t" arrives? Four. How
                                many possibilities remain after it has arrived? One. So you might
                                think the information transferred is four bits, but actually it is two.
                                Here's why (assuming that the four letters are equally probable,
                                like the four suits in a pack of cards). Remember that shannon's
                                metric is concerned with the most economical way of conveying
                                the message. Think of it as the number of yes/no questions that
                                you'd have to ask in order to narrow down to certainty, from an
                                initial uncertainty of four possibilities, assuming that you planned
                                your questions in the most economical way. "is the mystery letter
                                before d in the alphabet?" no. That narrows it down to t or g,
                                and now we need only one more question to clinch it. So, by this
                                method of measuring, each "letter" of the dna has an
                                information capacity of 2 bits.
                                Whenever prior uncertainty of recipient can be expressed as a
                                number of equiprobable alternatives n, the information content of
                                a message which narrows those alternatives down to one is log2n
                                (the power to which 2 must be raised in order to yield the number
                                of alternatives n). If you pick a card, any card, from a normal
                                pack, a statement of the identity of the card carries log252, or 5.7
                                bits of information. In other words, given a large number of
                                guessing games, it would take 5.7 yes/no questions on average to
                                guess the card, provided the questions are asked in the most
                                economical way. The first two questions might establish the suit.
                                (is it red? Is it a diamond?) the remaining three or four questions
                                would successively divide and conquer the suit (is it a 7 or higher?
                                Etc.), finally homing in on the chosen card. When the prior
                                uncertainty is some mixture of alternatives that are not
                                equiprobable, shannon's formula becomes a slightly more
                                elaborate weighted average, but it is essentially similar. By the
                                way, shannon's weighted average is the same formula as
                                physicists have used, since the nineteenth century, for entropy.
                                The point has interesting implications but i shall not pursue them
                                here.
                                Information and evolution
                                that's enough background on information theory. It is a theory
                                which has long held a fascination for me, and i have used it in
                                several of my research papers over the years. Let's now think how
                                we might use it to ask whether the information content of
                                genomes increases in evolution. First, recall the three way
                                distinction between total information capacity, the capacity that is
                                actually used, and the true information content when stored in the
                                most economical way possible. The total information capacity of
                                the human genome is measured in gigabits. That of the common
                                gut bacterium escherichia coli is measured in megabits. We, like
                                all other animals, are descended from an ancestor which, were it
                                available for our study today, we'd classify as a bacterium. So
                                perhaps, during the billions of years of evolution since that
                                ancestor lived, the information capacity of our genome has gone
                                up about three orders of magnitude (powers of ten) - about a
                                thousandfold. This is satisfyingly plausible and comforting to
                                human dignity. Should human dignity feel wounded, then, by the
                                fact that the crested newt, triturus cristatus, has a genome
                                capacity estimated at 40 gigabits, an order of magnitude larger
                                than the human genome? No, because, in any case, most of the
                                capacity of the genome of any animal is not used to store useful
                                information. There are many nonfunctional pseudogenes (see
                                below) and lots of repetitive nonsense, useful for forensic
                                detectives but not translated into protein in the living cells. The
                                crested newt has a bigger "hard disc" than we have, but since the
                                great bulk of both our hard discs is unused, we needn't feel
                                insulted. Related species of newt have much smaller genomes.
                                Why the creator should have played fast and loose with the
                                genome sizes of newts in such a capricious way is a problem that
                                creationists might like to ponder. From an evolutionary point of
                                view the explanation is simple (see the selfish gene pp 44-45 and
                                p 275 in the second edition).
                                Gene duplication
                                evidently the total information capacity of genomes is very
                                variable across the living kingdoms, and it must have changed
                                greatly in evolution, presumably in both directions. Losses of
                                genetic material are called deletions. New genes arise through
                                various kinds of duplication. This is well illustrated by
                                haemoglobin, the complex protein molecule that transports
                                oxygen in the blood.
                                Human adult haemoglobin is actually a composite of four protein
                                chains called globins, knotted around each other. Their detailed
                                sequences show that the four globin chains are closely related to
                                each other, but they are not identical. Two of them are called
                                alpha globins (each a chain of 141 amino acids), and two are beta
                                globins (each a chain of 146 amino acids). The genes coding for
                                the alpha globins are on chromosome 11; those coding for the beta
                                globins are on chromosome 16. On each of these chromosomes,
                                there is a cluster of globin genes in a row, interspersed with some
                                junk dna. The alpha cluster, on chromosome 11, contains seven
                                globin genes. Four of these are pseudogenes, versions of alpha
                                disabled by faults in their sequence and not translated into
                                proteins. Two are true alpha globins, used in the adult. The final
                                one is called zeta and is used only in embryos. Similarly the beta
                                cluster, on chromosome 16, has six genes, some of which are
                                disabled, and one of which is used only in the embryo. Adult
                                haemoglobin, as we've seen contains two alpha and two beta
                                chains.
                                Never mind all this complexity. Here's the fascinating point.
                                Careful letter-by-letter analysis shows that these different kinds of
                                globin genes are literally cousins of each other, literally members
                                of a family. But these distant cousins still coexist inside our own
                                genome, and that of all vertebrates. On a the scale of whole
                                organism, the vertebrates are our cousins too. The tree of
                                vertebrate evolution is the family tree we are all familiar with, its
                                branch-points representing speciation events - the splitting of
                                species into pairs of daughter species. But there is another family
                                tree occupying the same timescale, whose branches represent not
                                speciation events but gene duplication events within genomes.
                                The dozen or so different globins inside you are descended from
                                an ancient globin gene which, in a remote ancestor who lived
                                about half a billion years ago, duplicated, after which both copies
                                stayed in the genome. There were then two copies of it, in
                                different parts of the genome of all descendant animals. One copy
                                was destined to give rise to the alpha cluster (on what would
                                eventually become chromosome 11 in our genome), the other to
                                the beta cluster (on chromosome 16). As the aeons passed, there
                                were further duplications (and doubtless some deletions as well).
                                Around 400 million years ago the ancestral alpha gene duplicated
                                again, but this time the two copies remained near neighbours of
                                each other, in a cluster on the same chromosome. One of them
                                was destined to become the zeta of our embryos, the other became
                                the alpha globin genes of adult humans (other branches gave rise
                                to the nonfunctional pseudogenes i mentioned). It was a similar
                                story along the beta branch of the family, but with duplications at
                                other moments in geological history.
                                Now here's an equally fascinating point. Given that the split
                                between the alpha cluster and the beta cluster took place 500
                                million years ago, it will of course not be just our human genomes
                                that show the split - possess alpha genes in a different part of the
                                genome from beta genes. We should see the same within-genome
                                split if we look at any other mammals, at birds, reptiles,
                                amphibians and bony fish, for our common ancestor with all of
                                them lived less than 500 million years ago. Wherever it has been
                                investigated, this expectation has proved correct. Our greatest
                                hope of finding a vertebrate that does not share with us the ancient
                                alpha/beta split would be a jawless fish like a lamprey, for they
                                are our most remote cousins among surviving vertebrates; they are
                                the only surviving vertebrates whose common ancestor with the
                                rest of the vertebrates is sufficiently ancient that it could have
                                predated the alpha/beta split. Sure enough, these jawless fishes are
                                the only known vertebrates that lack the alpha/beta divide.
                                Gene duplication, within the genome, has a similar historic impact
                                to species duplication ("speciation") in phylogeny. It is
                                responsible for gene diversity, in the same way as speciation is
                                responsible for phyletic diversity. Beginning with a single
                                universal ancestor, the magnificent diversity of life has come
                                about through a series of branchings of new species, which
                                eventually gave rise to the major branches of the living kingdoms
                                and the hundreds of millions of separate species that have graced
                                the earth. A similar series of branchings, but this time within
                                genomes - gene duplications - has spawned the large and diverse
                                population of clusters of genes that constitutes the modern
                                genome.
                                The story of the globins is just one among many. Gene
                                duplications and deletions have occurred from time to time
                                throughout genomes. It is by these, and similar means, that
                                genome sizes can increase in evolution. But remember the
                                distinction between the total capacity of the whole genome, and
                                the capacity of the portion that is actually used. Recall that not all
                                the globin genes are actually used. Some of them, like theta in the
                                alpha cluster of globin genes, are pseudogenes, recognizably kin
                                to functional genes in the same genomes, but never actually
                                translated into the action language of protein. What is true of
                                globins is true of most other genes. Genomes are littered with
                                nonfunctional pseudogenes, faulty duplicates of functional genes
                                that do nothing, while their functional cousins (the word doesn't
                                even need scare quotes) get on with their business in a different
                                part of the same genome. And there's lots more dna that doesn't
                                even deserve the name pseudogene. It, too, is derived by
                                duplication, but not duplication of functional genes. It consists of
                                multiple copies of junk, "tandem repeats", and other nonsense
                                which may be useful for forensic detectives but which doesn't
                                seem to be used in the body itself.
                                Once again, creationists might spend some earnest time
                                speculating on why the creator should bother to litter genomes
                                with untranslated pseudogenes and junk tandem repeat dna.
                                Information in the genome
                                can we measure the information capacity of that portion of the
                                genome which is actually used? We can at least estimate it. In the
                                case of the human genome it is about 2% - considerably less than
                                the proportion of my hard disc that i have ever used since i bought
                                it. Presumably the equivalent figure for the crested newt is even
                                smaller, but i don't know if it has been measured. In any case, we
                                mustn't run away with a chauvinistic idea that the human genome
                                somehow ought to have the largest dna database because we are
                                so wonderful. The great evolutionary biologist george c williams
                                has pointed out that animals with complicated life cycles need to
                                code for the development of all stages in the life cycle, but they
                                only have one genome with which to do so. A butterfly's genome
                                has to hold the complete information needed for building a
                                caterpillar as well as a butterfly. A sheep liver fluke has six
                                distinct stages in its life cycle, each specialised for a different way
                                of life. We shouldn't feel too insulted if liver flukes turned out to
                                have bigger genomes than we have (actually they don't).
                                Remember, too, that even the total capacity of genome that is
                                actually used is still not the same thing as the true information
                                content in shannon's sense. The true information content is what's
                                left when the redundancy has been compressed out of the
                                message, by the theoretical equivalent of stuffit. There are even
                                some viruses which seem to use a kind of stuffit-like
                                compression. They make use of the fact that the rna (not dna
                                in these viruses, as it happens, but the principle is the same) code
                                is read in triplets. There is a "frame" which moves along the rna
                                sequence, reading off three letters at a time. Obviously, under
                                normal conditions, if the frame starts reading in the wrong place
                                (as in a so-called frame-shift mutation), it makes total nonsense:
                                The "triplets" that it reads are out of step with the meaningful ones.
                                But these splendid viruses actually exploit frame-shifted reading.
                                They get two messages for the price of one, by having a
                                completely different message embedded in the very same series of
                                letters when read frame-shifted. In principle you could even get
                                three messages for the price of one, but i don't know whether
                                there are any examples.
                                Information in the body
                                it is one thing to estimate the total information capacity of a
                                genome, and the amount of the genome that is actually used, but
                                it's harder to estimate its true information content in the shannon
                                sense. The best we can do is probably to forget about the genome
                                itself and look at its product, the "phenotype", the working body
                                of the animal or plant itself. In 1951, j w s pringle, who later
                                became my professor at oxford, suggested using a shannon-type
                                information measure to estimate "complexity". Pringle wanted to
                                express complexity mathematically in bits, but i have long found
                                the following verbal form helpful in explaining his idea to
                                students.
                                We have an intuitive sense that a lobster, say, is more complex
                                (more "advanced", some might even say more "highly evolved")
                                than another animal, perhaps a millipede. Can we measure
                                something in order to confirm or deny our intuition? Without
                                literally turning it into bits, we can make an approximate
                                estimation of the information contents of the two bodies as
                                follows. Imagine writing a book describing the lobster. Now write
                                another book describing the millipede down to the same level of
                                detail. Divide the word-count in one book by the word-count in
                                the other, and you have an approximate estimate of the relative
                                information content of lobster and millipede. It is important to
                                specify that both books describe their respective animals "down to
                                the same level of detail". Obviously if we describe the millipede
                                down to cellular detail, but stick to gross anatomical features in
                                the case of the lobster, the millipede would come out ahead.
                                But if we do the test fairly, i'll bet the lobster book would come
                                out longer than the millipede book. It's a simple plausibility
                                argument, as follows. Both animals are made up of segments -
                                modules of bodily architecture that are fundamentally similar to
                                each other, arranged fore-and-aft like the trucks of a train. The
                                millipede's segments are mostly identical to each other. The
                                lobster's segments, though following the same basic plan (each
                                with a nervous ganglion, a pair of appendages, and so on) are
                                mostly different from each other. The millipede book would
                                consist of one chapter describing a typical segment, followed by
                                the phrase "repeat n times" where n is the number of segments.
                                The lobster book would need a different chapter for each segment.
                                This isn't quite fair on the millipede, whose front and rear end
                                segments are a bit different from the rest. But i'd still bet that, if
                                anyone bothered to do the experiment, the estimate of lobster
                                information content would come out substantially greater than the
                                estimate of millipede information content.
                                It's not of direct evolutionary interest to compare a lobster with a
                                millipede in this way, because nobody thinks lobsters evolved
                                from millipedes. obviously no modern animal evolved from any
                                other modern animal. Instead, any pair of modern animals had a
                                last common ancestor which lived at some (in principle)
                                discoverable moment in geological history. Almost all of
                                evolution happened way back in the past, which makes it hard to
                                study details. But we can use the "length of book" thoughtexperiment
                                to agree upon what it would mean to ask the question
                                whether information content increases over evolution, if only we
                                had ancestral animals to look a
                                t.
                                the answer in practice is complicated and controversial, all bound
                                up with a vigorous debate over whether evolution is, in general,
                                progressive. I am one of those associated with a limited form of
                                yes answer. My colleague stephen jay gould tends towards a no
                                answer.
                                i don't think anybody would deny that, by any method of
                                measuring - whether bodily information content, total information
                                capacity of genome, capacity of genome actually used, or true
                                ("stuffit compressed") information content of genome - there has
                                been a broad overall trend towards increased information content
                                during the course of human evolution from our remote bacterial
                                ancestors. People might disagree, however, over two important
                                questions: First, whether such a trend is to be found in all, or a
                                majority of evolutionary lineages (for example parasite evolution
                                often shows a trend towards decreasing bodily complexity,
                                because parasites are better off being simple); second, whether,
                                even in lineages where there is a clear overall trend over the very
                                long term, it is bucked by so many reversals and re-reversals in
                                the shorter term as to undermine the very idea of progress. This is
                                not the place to resolve this interesting controversy. There are
                                distinguished biologists with good arguments on both sides.
                                Supporters of "intelligent design" guiding evolution, by the way,
                                should be deeply committed to the view that information content
                                increases during evolution. Even if the information comes from
                                god, perhaps especially if it does, it should surely increase, and
                                the increase should presumably show itself in the genome. Unless,
                                of course - for anything goes in such addle-brained theorising -
                                god works his evolutionary miracles by nongenetic means.
                                Perhaps the main lesson we should learn from pringle is that the
                                information content of a biological system is another name for its
                                complexity. Therefore the creationist challenge with which we
                                began is tantamount to the standard challenge to explain how
                                biological complexity can evolve from simpler antecedents, one
                                that i have devoted three books to answering (the blind
                                watchmaker, river out of eden, climbing mount improbable)
                                and i do not propose to repeat their contents here. The
                                "information challenge" turns out to be none other than our old
                                friend: "how could something as complex as an eye evolve?" it is
                                just dressed up in fancy mathematical language - perhaps in an
                                attempt to bamboozle. Or perhaps those who ask it have already
                                bamboozled themselves, and don't realise that it is the same old -
                                and thoroughly answered - question.
                                The genetic book of the dead
                                let me turn, finally, to another way of looking at whether the
                                information content of genomes increases in evolution. We now
                                switch from the broad sweep of evolutionary history to the
                                minutiae of natural selection. Natural selection itself, when you
                                think about it, is a narrowing down from a wide initial field of
                                possible alternatives, to the narrower field of the alternatives
                                actually chosen. Random genetic error (mutation), sexual
                                recombination and migratory mixing, all provide a wide field of
                                genetic variation: The available alternatives. Mutation is not an
                                increase in true information content, rather the reverse, for
                                mutation, in the shannon analogy, contributes to increasing the
                                prior uncertainty. But now we come to natural selection, which
                                reduces the "prior uncertainty" and therefore, in shannon's sense,
                                contributes information to the gene pool. In every generation,
                                natural selection removes the less successful genes from the gene
                                pool, so the remaining gene pool is a narrower subset. The
                                narrowing is nonrandom, in the direction of improvement, where
                                improvement is defined, in the darwinian way, as improvement in
                                fitness to survive and reproduce. Of course the total range of
                                variation is topped up again in every generation by new mutation
                                and other kinds of variation. But it still remains true that natural
                                selection is a narrowing down from an initially wider field of
                                possibilities, including mostly unsuccessful ones, to a narrower
                                field of successful ones. This is analogous to the definition of
                                information with which we began: Information is what enables the
                                narrowing down from prior uncertainty (the initial range of
                                possibilities) to later certainty (the "successful" choice among the
                                prior probabilities). According to this analogy, natural selection is
                                by definition a process whereby information is fed into the gene
                                pool of the next generation.
                                If natural selection feeds information into gene pools, what is the
                                information about? It is about how to survive. Strictly it is about
                                how to survive and reproduce, in the conditions that prevailed
                                when previous generations were alive. To the extent that present
                                day conditions are different from ancestral conditions, the
                                ancestral genetic advice will be wrong. In extreme cases, the
                                species may then go extinct. To the extent that conditions for the
                                present generation are not too different from conditions for past
                                generations, the information fed into present-day genomes from
                                past generations is helpful information. Information from the
                                ancestral past can be seen as a manual for surviving in the present:
                                A family bible of ancestral "advice" on how to survive today. We
                                need only a little poetic licence to say that the information fed into
                                modern genomes by natural selection is actually information
                                about ancient environments in which ancestors survived.
                                This idea of information fed from ancestral generations into
                                descendant gene pools is one of the themes of my new book,
                                unweaving the rainbow. It takes a whole chapter, "the genetic
                                book of the dead", to develop the notion, so i won't repeat it here
                                except to say two things. First, it is the whole gene pool of the
                                species as a whole, not the genome of any particular individual,
                                which is best seen as the recipient of the ancestral information
                                about how to survive. The genomes of particular individuals are
                                random samples of the current gene pool, randomised by sexual
                                recombination. Second, we are privileged to "intercept" the
                                information if we wish, and "read" an animal's body, or even its
                                genes, as a coded description of ancestral worlds. To quote from
                                unweaving the rainbow:
                                "and isn't it an arresting thought? We are digital archives of the
                                african pliocene, even of devonian seas; walking repositories of
                                wisdom out of the old days. You could spend a lifetime reading in this
                                ancient library and die unsated by the wonder of it."
                                1 the producers never deigned to send me a copy: I completely forgot
                                about it until an american colleague called it to my attention.
                                2 see barry williams (1998): Creationist deception exposed, the
                                skeptic 18, 3, pp 7-10, for an account of how my long pause (trying to
                                decide whether to throw them out) was made to look like hesitant
                                inability to answer the question, followed by an apparently evasive
                                answer to a completely different question.
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