Richard Dawkins Greatest Show on Earth

in his book the greatest show on earth the evidence for evolution richard dawkins argues that denying evolution today is comparable to denying the holocaust the new york academy of sciences in new york city hosts this hour minute event we have a war on our hands you've just heard that more than forty percent of the us population according to gallup believes that the world came into existence less than 10 000 years ago that is a quite astonishing disconnect from reality the reality is that the world is 4.6 billion years old and i've um mentioned this calculation many times before the equivalent of believing that the world is only six thousand years old which is the official biblical figure is to believe that the distance from new york to san francisco is less than 80 yards that's the scale of the error that we're talking about and it's an error that if gallup is to be believed uh is in the minds of 44 of the american population at the beginning of this book i have likened the predicament of a science teacher today to a latin teacher or teacher of latin and roman history having to contend with a sort of rear guard defense having to put out a rearguard defense of the proposition that the romans existed at all and that the latin language was ever spoken rather than being an invention to keep victorian school masters in in employment i've also likened the history denial shown by these young earth creationists to holocaust deniers in the sense that the evidence for evolution is as strong as the evidence for the holocaust i hasten to say i'm not suggesting that evolution deniers are motivated by the same sinister political agenda as holocaust deniers are they're motivated by a different sinister political agenda but i don't want to make this book seem like a negative debunking kind of book it isn't mainly that the evidence for evolution is above all positive it's enthralling it's exciting it's it is the greatest show on earth life on this planet is the greatest show on earth and life on this planet may well be the greatest show in the universe because we have no evidence that anything like the quite astounding phenomena of life are to be found anywhere else in the universe maybe they are uh in which case um life is the greatest show in the universe still the first chapter also considers the definition of the word theory which as you know is much misunderstood and i quote two definitions from the oxford dictionary one of which is the tentative only a theory only a hypothesis that needs falsifying or verifying and the other being the sort of meaning that a scientist uses when when talking about say the heliocentric theory of the solar system or the theory of gravitation or the atomic theory of matter and it's of course in that sense that evolutionism is a theory but in ordinary colloquial language evolution is a fact chapter 2 dogs cows and cabbages follows darwin in making use of domestication the astonishing power of selective breeding to produce from a wolf dog or from the wild cabbage brassica oloracia all the different varieties of cabbage like plants that we eat cauliflower brussels sprouts broccoli and various sorts of cabbage and so on if you wanted to do an experiment to test the theory of natural selection what would you do well experiment implies human intervention what you would do would be to administer the selective force yourself as an experimenter in other words you would do artificial selection which is what humans have done inadvertently at first in breeding dogs and cabbages and pigeons and so on and also experimentally there are numerous experiments where people have administered a selective pressure on populations of animals and plants and produced dramatic results dramatic evolutionary change in a very short time within one human lifetime a nice example is the work of belief russian geneticist who studied silver foxes and bred them artificially for tameness and he succeeded in breeding super tame foxes which behaved like dogs licked your face wagged their tail behaved just like dogs what's more interesting is that after only about 30 years he's he has these foxes that look like dogs they they look like coli dogs no longer look like foxes they've got black and white patches on their coast they've got floppy ears they bark like dogs that is a curious phenomenon of traits being dragged along in the wake of other ones he selected only for tameness but what he got was dog-like characteristics in all sorts of other respects that's an interesting side glance the important point is that he produced dramatic evolutionary change in a mere 30 years if you can do that in 30 years just think what could be achieved in 100 million years it would not be artificial selection of course it would be natural selection coming on to that chapter three the primrose path to macro evolution this chapter is an exercise in seduction starting with artificial selection which we've just been talking about showing the power of artificial selection i'm trying gradually to wean the reader on to natural selection by going through a number of intermediate stages the p hen selects the peacock in something like the same way as human breeders select frisian cattle or white lagoon hens peahens of course don't consciously choose peacocks they do choose peacocks on the basis of that which appeals to them aesthetically you can use the word aesthetically and the result is the astonishing flamboyant splendor of the peacock the same thing happens with birds of paradise numerous other birds insects fish amphibians mammals and so on flowers the brightness of flowers the bright colors of flowers the the exotic the seductive perfumes of flowers these were first of all chosen by insects choosing the flowers that they would visit to and and from the flower's point of view pollinate that's what the flower gets out of it the insect gets nectar of course usually what the insects started human horticulturalists carried on with so something like a wild rose pretty little flower but nothing to compare with the beautiful roses that human gardeners have produced by artificial selection the beautiful perfumes what i'm saying what the point i'm making is that what human selectors have done is simply to carry on where the insect selectors left off so we can regard insects as doing the same kind of job as human artificial selectors anglerfish have a fishing rod sticking out of the top of their head uh with a bait on the end and they play their prey small prey down into the vicinity cast the rod down into the vicinity of the mouth small fish are attracted to the bait when they get sufficiently close to the mouth the anglerfish opens up it's great more and the inrush of water sucks in the prey obviously a very sensible way to get prey from the point of view of the victim the prey fish you could say that the prey fish are acting as selective breeders selecting anglerfish for more effective bait now obviously it's not to the advantage of the prey to do that nevertheless that is what they're doing so you see how the pa the primrose path to macroevolution the seductive path is working i'm gradually moving towards natural selection in natural selection we've already got to natural selection of course but in ordinary natural selection we generalize it and say that any any variation any genetic variation whatsoever whether it's visible on the outside as all the examples i've talked about so far have been or a purely internal change genetic change some subtle detail of biochemistry something that you'd never notice on the outside at all if it contributes in any way to the survival or reproduction and or reproduction of the animal that will be positively uh or negatively selected we've moved now up the primrose path of seduction from artificial selection which anybody can understand which was understood of course long before darwin to natural selection which only darwin and wallis could it could be argued anyway really grasped it was darwin and wallis who saw the principle of artificial selection that everybody understood could be generalized to nature nature just means that some animals survive and some animals don't survive for whatever reason and that has exactly the same effect as if there was a human breeder choosing which puppies to save and which puppies to kill which puppies to breed from which puppies not to breed from in order to get major macroevolutionary change such as changing fish into mammals you need time artificial selection we've seen that in human terms in a few centuries we've seen what can be done but in natural selection evolution we've got hundreds of millions of years we need to know how we've set out the evidence that we do have hundreds of millions of years in darwin's time this was doubted darwin's time the senior british physicist of the day lord kelvin demonstrated to the satisfaction of himself and other physicists that the sun and the earth were only a few million years old not long enough for evolutionary change this worried darwin because he was a humble man and he recognized as many of us do that physics is kind of the senior science and so he kind of he never actually caved in but it did worry him um it the the basis for kelvin's miscalculation was that he being a victorian scientist thought that the sun was was doing combustion was burning something he didn't really think it was coal but something like um burning coal in which case his calculation would have been correct it's a nice quirk of history that it fell to charles darwin's son sir george darwin charles himself was never knighted his son sir george darwin um to demonstrate to the british association in the early uh 20th century that um uh the sun because it was a nuclear reactor had plenty of time to have given all the time we need for evolution what darwin should have said to lord kelvin is well if your physics tells you that the earth is not old enough for evolution to have taken place then i'm sorry your physics is wrong because the evidence from biology is overwhelming uh that would have been the correct response as it turned out it the refutation came finally from from physics my chapter mostly goes into the details of how we know how old the earth is how we know how old uh fossils are mostly using a radioactive dating physicist will tell us the half-life of isotopes and these isotopes gives for example potassium 40 decays to argon 40 and with a half-life of 1.26 billion years at the moment when molten lava solidifies crystals are formed and at that moment you could say that the clock is zeroed the clock the potassium clock is is zeroed the argon 40 content is zero and at any later time if you measure the argon the argan 40 content and the potassium 40 content and compare the two knowing the half-life of this particular decay you can calculate the exact moment within ordinary limits of error the exact moment when that crystal was formed when that lava solidified fossils don't appear in don't occur in igneous rock so you have to look for igneous rock that is to be found in the vicinity of a fossil in sedimentary rock and that's not too difficult to do and the science of dating is now well developed and it's how we know how old fossils are and how we know how old the earth is 4.6 billion years there are other ways in which we know that as well the next chapter before our very eyes i've said that uh mostly evolution takes a very very long time and uh there are exceptions to that there are some cases where we see natural evolution taking place sufficiently fast that an individual scientist can study it within one scientific lifetime a matter of a matter of decades and i discuss a number of examples of this but there are fairly few these examples compared with the evidence that we have from the massive amount of time that's been available for long-term macroevolution and for that i use the analogy it's a recurrent analogy throughout the book of a detective coming on the scene of a crime too late to be an eyewitness and this would be the normal situation for a detective it's not granted to many detectives to actually be eyewitnesses to a murder they come upon the murder afterwards and they then look at clues which remain fingerprints footprints bloodstains all sorts of other things that are left lying around and from this the detective infers what must have happened the equivalent for evolution is clues that remain which hugely outnumber in in number and strength the clues that are available to any detective in any ordinary murder mystery so beyond reasonable doubt which is the criterion that juries are supposed to work to the evidence for evolution is far beyond reasonable doubt it's just beyond all possible conceivable sane sensible doubt chapter six missing link what do you mean missing creationists love the fossil record because they think it's an embarrassment to evolutionists because they point out that there are gaps in the fossil record well of course there are gaps in the fossil record what do you expect would you expect every single species that's ever lived to fossilize we're lucky to have fossils at all if we didn't have a single fossil if not a single corpse that ever fossilized the evidence for evolution would be utterly secure we don't need fossils to demonstrate evolution it's nice that we've got them because they tell us a lot about the history of life but we don't need them to demonstrate that evolution is a fact the evidence comes from other sources the the biggest gap and one the creationists love best of all is the gap before the cambrian era just over half a billion years ago before that time there were rather few fossils and most of the major animal phyla appear relatively suddenly in the fossil record in the cambrian i wrote in an earlier book i'm going to just read a passage yes in the blind watchmaker in 1986 i wrote the cambrian shows us a substantial number of major animal phyla already in an advanced state of evolution the very first time they appear it is although they were just planted there without any evolutionary history you can see how naive i was in 1986 not to realize how shamelessly that would be quote mined it's as though they were just planted there without any evolutionary history needless to say this appearance of sudden planting has delighted creationists i was savvy enough to realize that uh they would like that i decided to search the world wide web for that sentence it is although they were just planted there without any evolutionary history to see how many hits i got and i obtained no fewer than 1 250 hits for that sentence well you need a control if you're a scientist to compare that with otherwise you don't know what you expect to get how many hits you'd expect to get for from a sentence like that so i looked at the very next sentence from the blind watchmaker which was evolutionists of all stripes believe however that this really does represent a very large gap in the fossil record the number of hits i obtained for that as compared to the 1250 for the first quote the number of of hits i obtained for the second quote was 63. the ratio of 1250 to 63 is 19.8 and i call that ratio the quote mining index the quote mining index is also very high for the famous quote from darwin where he talks about the eye and says something like to suppose that the i with all its and he goes into detailed uh sentence about all the highly complicated ways in which eyes are adapted and adjusted and do self-focusing and self-stopping down he says to suppose that the eye could have been formed by numerous small small incremental changes seems absurd in the highest degree if he then of course goes on but that's where the quote stops and they miss out um darwin's immediately following explanation for how actually although it seems absurd it's not absurd and once again we have a very high quote mining index the ratio i've done it for that too the ratio of the two the number of hits for the two quotes is is also very high what is well before leaving the cambrian explosion i just want to make one more point um there are modern animals for example flatworms the great phylum platyhelminthes which includes tapeworms and flukes and free-living turbuleria which are beautiful animals they're delightful animals often very brightly coloured very ubiquitous very common enormously common more more there are more species than there are mammals for example not a single fossil of a platyhelminth has ever been found or authentically found in other words we have here a major modern phylum which has no fossil history at all it is as though it were planted here yesterday so you see how illogical it is to say that because there are no fossils before a certain point therefore there were no animals there are all sorts of reasons why an animal doesn't fossil it may be too small it may be that it doesn't have hard skeletal parts that's the case for the flatworms for example i'm going to read another short passage from this chapter what would be evidence against evolution and very strong evidence of that would be the discovery of even a single fossil in the wrong geological stratum jbs haldane famously retorted when asked to name an observation that would disprove the theory of evolution fossil rabbits in the pre-cambrian no such rabbits no authentically anachronistic fossils of any kind have ever been found all the fossils that we have and there are very very many indeed occur without a single authenticated exception in the right temporal sequence yes there are gaps where there are no fossils at all and that's only to be expected but not a single solitary fossil has ever been found before it could have evolved that's a very telling fact there's no reason why we should expect it on the creationist theory a good theory a scientific theory is one that is vulnerable to disprove yet is not disproved evolution could so easily be disproved if just a single fossil turned up in the wrong date order evolution has passed this test with flying colours skeptics of evolution who wish to prove their case should be diligently scrabbling around in the rocks desperately trying to find anachronistic fossils maybe they'll find one want a bet the next chapter carries on the theme of fossils into human fossils it's called missing persons missing no longer and i'm going to read just a little bit about the uh type specimen of australopithecus africanus which is the so-called tong child australopithecus was the genus that almost certainly preceded our own genus homo in our evolutionary ancestry in other words we're almost certainly descended from members of the genus australopithecus although it may not be any one of the species that have so far been named the first australopithecine to be discovered and the type specimen of the genus was the so-called torn child at the age of three and a half the torn child was eaten by an eagle the evidence is the damage marks to the eye sockets of the fossil are identical to marks made by modern eagles on modern monkeys as they rip out their eyes poor little torn child shrieking on the wind as you were born aloft by the aqualine fury you would have found no comfort in your destiny fame two and a half million years on as the type specimen of australopithecus africanus poor tong mother weeping in the pliocene i want at this point to raise a point of terminology which i think is extremely relevant the tong child i said was the type specimen of australopithecus africanus that means it's the specimen that was first discovered and described and to which people refer when they have a new specimen and they want to know does it belong to this species or not so each new fossil or new animal indeed that that's discovered is always given a linnean binomial name a specific name preceded by a generic name like homo sapiens australopithecus africanus uh or whatever it is when a fossil is actually intermediate between two species or two genera and on the evolutionary view that there must be such fossils we are not allowed by our conventions of nomenclature to give it an intermediate name there's no machinery in in language to give a name that is intermediate between say australopithecus afarensis and homo habilis yet if that there must have been a member of the genus homo that was the immediate child of a member of the genus australopithecus but you can immediately see that that's nonsense because how could a baby be a different genus from its from its mother obviously in every single case every baby born is the same species let alone the same genus as its mother if you were to walk backwards down through your ancestral tree starting with your mother and then your grandmother great grandmother let's just stick to females for convenience great great grandmother and so on you would go back and back and back and back and back go back as far as you like and gradually the animals that you that you were walking past as you walk past your ancestors would be gradually ever so slowly changing into something else by the time you got back to about six or seven million years ago you'd be looking at an animal which was the common ancestor between ourselves and chimpanzees you could then if you wish uh turn around and start walking forwards along the line leading to chimpanzees at every single point along that sequence the animals that you are looking at would belong to the same species as their immediate neighbors which would be their mother and their daughter they would be more alike than members of species ordinarily are because they would because they would be mother and daughter therefore they would be more alike and yet if you walk back sufficiently far they would have changed from modern homo sapiens to a completely different genus you could go back to a fish using the same technique and by the time you got to the to the end of your walk you would have walked through a continuously changing set of animals all the way from human to fish then you could walk forwards again from fish to i don't know what i mean a kangaroo or something in every single case you would be you would be seeing animals that are of the same species as their neighbors in the sequence and yet the changes are so slow we get so persistent that eventually you get back to a fish it's not all that surprising because after all when a baby turns into an adult you don't suddenly say aha it ceased to be a baby it's now turned into a child and then our hearts and ceased to be a child has now become an adult it happens so gradually you don't notice the change it we're like a flea sitting on the hour hand of a watch you can't see it you can't see it moving it moves so slowly that you that that you don't see it now in spite of that we do force upon every fossil that we find by convention the binomial name either say australopithecus afarensis or homo habilis and that's meat and drink to creationists because whenever a fossil is found it's either an ape or a human we don't have a name for an intermediate we can't call it an intermediate because when we don't have the nomenclature or apparatus to do so and they prey on that convention and maybe it's time evolutionists started while never actually abandoning the the linnaean binomial convention nevertheless admit that there may be times when a fossil doesn't deserve to be given a name simply should be called intermediate between some other recognized fossils think about it another way if every creature that had ever lived fossilized then naming would be impossible everything would be intermediate you'd have to give it a name that reflected the shading between species and genera the next chapter i'm just going to read the beginning that irascible genius jbs haldane who did so much else besides being one of the three leading architects of neo-darwinism was once challenged by a lady after a public lecture it's a word-of-mouth anecdote and john maynard smith is sadly not available to confirm the exact words but this is approximately how the exchange went evolution skeptic professor haldane even given the billions of years that you say were available for evolution i simply cannot believe it is possible to go from a single cell to a complicated human body with its trillions of cells organized into bones and muscles and nerves a heart that pumps without ceasing for decades miles and miles of blood vessels and kidney tubules and a brain capable of thinking and talking and feeling jbs but madam you did it yourself and it only took you nine months that chapter is about embryology and the important relationship between embryology and evolution you can't understand evolution fully unless you have some grasp of the embryonic processes that generation after generation start with a single cell and give rise to an adult which then reproduces producing a new single cell and so on the processes of embryology are extremely complex they themselves must have evolved and that that chapter is aimed at that understanding the next chapter the arc of the continents is about the geographical distribution of animals and plant species in the islands and continents of the world which coming back to our detective analogy are exactly what you would expect them to be if they had evolved and exactly what you would not expect them to be if they had been created especially if they had been uh released from noah's ark uh i'll read a short paragraph or two from that chapter it is almost too ridiculous to mention it but i'm afraid i have to because of the more than 40 of the american population who as i lamented in chapter 1 accept the bible literally think what the geographical distribution of animals should look like if they'd all dispersed from noah's ark shouldn't there be some sort of law of decreasing species diversity as we move away from an epicenter perhaps mount ararat i don't need to tell you that is not what we see why would all those marsupials ranging from tiny pouched mice through koalas and bilbies to giant kangaroos and diprotodons why would all those marsupials but no placentals at all have migrated on mass from mount ararat to australia which route did they take why did not a single member of their straggling caravan pause on the way and settle in india perhaps or china or some haven along the great silk road why did the entire order identitator all 20 species of armadillo including the extinct giant armadillo all six species of sloth including extinct giant sloths and all four species of anteater troop off unerringly for south america leaving not a rack behind leaving no hide nor hair nor armor plate of settlers somewhere along the way why did all the penguins undertake the long waddle south to the antarctic not a single one to the equally hospitable arctic once again i'm sorry to take a sledgehammer to so small and fragile a nut that i have to do so i have to do so because more than 40 of the american people believe literally in the story of noah's ark we should be able to ignore them and get on with our science but we can't afford to because they control school boards they homeschool their children to deprive them of access to proper science teachers and they include many members of the united states congress some state governors and even presidential and vice presidential candidates they have the money and the power to build institutions universities even a museum where children ride life-size mechanical models of dinosaurs with saddles which they're solemnly told coexisted with humans we can't afford to be snooty in britain about that 28 of the british population get their science from the flintstones as well believing that humans coexisted with dinosaurs the next chapter the tree of cousinship here i think we come to perhaps the most powerful evidence of all for evolution looking at the enormous numbers of modern species that there are and comparing them systematically darwin was able to do this with anatomy skeletons for example he was able to see that the hand of a man and the wing of a bat are directly homologous and bat's wing is enormously long splayed out fingers with webbing stretched between the fingers a horse's hoof is the same hand where of the five fingers only the middle one remains and the horse walks on the middle finger and the middle toe and the hoof is the is the nail you can see that you can see it in the fossil record how the number of fingers diminished and there are occasional freak horses uh which are born with three toes showing an intermediate uh stage but that was the limit of what was possible in in in darwin's time you could compare anatomy and show very very convincingly that it fell on a family tree nowadays you can do the same thing with molecules with with genes molecularly analyzed and the sheer amount of information available is is multiplied many orders of magnitude because the genetic code is universal all creatures have the same machine code the same code whereby triplets of dna are rendered into amino acids you can directly compare the same gene in one animal with the same gene in another animal you know it's the same gene it's got essentially the same sequence with minor differences there's a letter different here a letter different there better different there and the corresponding differences appear in the amino acids and in the protein chain that they produce but you can say this is the same gene it's doing the same job it's got the same sequence with these minor differences and then you can literally count the number of differences between these genes it's not a case of saying oh this limb looks a bit like that limb you are literally comparing alternative texts just like alternative versions of of the book of isaiah or something where you just look at count the number of differences that there are between chapters between letters between sentences words and when you do that for any one gene you like you find that the differences fall on a beautiful hierarchical tree what could that be but a family tree what could that be but a pedigree then you do the same thing for another gene and you find the same tree then you do it for another gene and you find the same tree then you do it for a gene which no longer does anything but you can still sequence it nature doesn't read the gene anymore it's never translated into protein but molecular geneticists can read it and they can recognize that it is a defunct version of the same gene and again when you compare these pseudo genes you find the same family tree there are minor exceptions to that but in general it's it's dramatically true that if you look at different genes you find they fall on the same tree what could that tree be butter family tree the only alternative is that the intelligent designer the creator deliberately set out to to deceive us and make it look as though evolution had happened when it didn't that's not a resort that i think many theists would wish to cling to next chapter history written all over us when you look at modern animals you don't need to look at fossils just look at modern animals and you can see their history written all over them look at a dolphin look at a whale it's a purely aquatic animal lives only in the sea but you can tell from looking at it that it has all the hallmarks of a land mammal it's descended from a land mammal our bodies any animal's body has mistakes which no designer would ever have perpetrated and yet which clearly are understandable if you think historically if you think this is descended from an ancestor which did things differently i was privileged to be um attendant i supposedly the right word on a dissection of a giraffe's neck a few week a few months ago while i was writing the book in fact and we were dissecting the recurrent laryngeal nerve of this giraffe which had unfortunately died in a zoo the recurrent laryngeal nerve is one of the it's a branch of one of the cranial nerves it starts with the in the brain and it its end organ is the larynx the voice box so you might think that if a designer had made this nerve he would have made it go straight from the brain to the larynx which is what most nerves do this nerve however goes right past the larynx way down into the chest loops around one of the main arteries in the chest different one on different sides and then goes back up to the larynx in a human that's a detour of a foot or so in a giraffe it's a detour of 15 feet or so i watched this nerve as it was being dissected out it go it goes within an inch or so of the larynx and it goes straight past it and then goes on south on and on and on and on down into the chest turns around and goes back up again no designer in his senses would ever have done that yet it makes perfect sense when you think of it historically when you look back to the fish ancestors of mammals where that nerve was doing something very different and the most direct route to what was then its end organ was indeed posterior to the artery that we're talking about then when mammal neck started when fish don't have necks when mammal neck started to elongate the it would it might have been possible to to loop the nerve over so that it went north of the artery instead of south of the artery but in fact what happened was that the it just stayed elongating as the neck lengthened the marginal cost of elongating the detail was so slight compared to uh just um the enormous cost of what probably would have been an enormous cost of changing the embryological changing the embryonic processes in order to completely re-route the nerve into what would be a more economical way of doing it the marginal cost was slight just another millimeter what's another millimeter evolution happens gradually just elongated a bit more human designers intelligent designers of all kinds go back to the drawing board when they when they've got a new design when the jet engine when the jet plane was invented when the jet engine was invented the designer of the first jet engine started with a clean drawing board he didn't start with a propeller engine and then modify it rivet by rivet screw by screw nut by nut which is the equivalent of the way evolution has to work imagine what a jet plane would look like if it was a gradually step-by-step modified propeller plane that's what that's the limitation under which evolution is working given that it's amazing that animals work so well the reason they work so well is despite these bodgies these bungles as we would look at as an engineer would call them evolution natural selection is a brilliant tinkerer that comes along afterwards and makes corrections after the event so for example with the with the the vertebrate retina in the eye which is back to front once again what an atrocious piece of bad design that is the photocells that are detecting the light are facing backwards and the wires that connect them to the brain are in front in the way of the light and they have to dive through the retina in the so-called blind spot what designer would ever have done that yet we see very well because natural selection makes up for the initial barge by superb tinkering and detail which means that we end up seeing um very well arms races and evolutionary theodicy chapter 12 the evolutionary arms race i think is a very important and interesting idea animals become adapted to their environment but if the environment is the inanimate environment like the weather say an ice age comes and then a drought comes and then a flood comes and something else comes the evolution of the animals just tracks the environmental change when the cold weather comes they get shaggier coats when the cold weather goes the coats become less shaggy this all happens in evolutionary time but what if it's not the weather we're talking about but predators predators are actually getting better at being predators because they're evolving too on the other side prey animals are getting better at getting away from predators so unlike the weather which is maybe unpleasant but it's not deliberately out to get you predators are and prey animals are deliberately out to get away from you and they're getting better at it and so in evolutionary time we see an arms race where the predators get a bit faster at running and the prey animals have to get a bit faster and the predators get faster and it goes on escalating until now you see superb feats of speed by cheetahs and leopards on the one side and by gazelles antelopes zebras uh american antelopes on the other hand on the on the other side and when you look at any beautifully designed apparently designed piece of biological machinery like an eye or an or a knee joint a fast running leg an efficiently pumping heart that goes on for a long time what you're looking at is the end product of an evolutionary arms race of several evolutionary arms races run in evolutionary time not to be confused with the race that's run in real time between an individual leopard and an individual antelope so the arms race is a race to improve the equipment for survival this is an economical shift it's got to be an economic shift into the weaponry of the arms race whether it's long-running legs or sharp teeth or keen eyes or whatever it is from something else in the economy of the body because the body is a very thrifty economy has to be like for example making milk if only the leopards and the antelopes could come to some kind of trades union agreement that they're not that they're not going to say the antelopes are going to send a tithe of their number to be eaten uh each each year um then neither side would have to develop fast running limbs at all they could just get on with the business of reproduction everybody would be better off but of course that's not how evolution works evolution works at the individual level i'm going to read a little bit about arms races one thing about arms races that might worry enthusiasts for intelligent design is the heavy dose of futility that loads them down if we're going to postulate a designer of the cheetah he has evidently put every ounce of his designing expertise into the task of perfecting a superlative killer one look at that magnificent running machine leaves us in no doubt the cheetah if we're going to talk design at all is superbly designed for killing gazelles but the very same designer has equally evidently strained every nerve to design a gazelle that is superbly equipped to escape those very same cheaters for heaven's sake whose side is the designer on when you look at the cheetahs taught muscles and flexing backbone you must conclude that the designer wants the cheetah to win the race but when you look at the sprinting jinking dodging gazelle you reach exactly the opposite conclusion does the designer's left hand not know what his right hand is doing is he a sadist who enjoys the thrill who enjoys the spectator sport and is forever upping the ante on both sides to increase the thrill of the chase did he who made the lamb make thee is it really part of the divine plan that the leopard shall lie down with the kid and the lion eats straw like the ox in that case what priced the formidable carnacion teeth the murderous claws of the lion and the leopard whence the breathtaking speed and agile escapology of the antelope and the zebra needless to say no such problems arise on the evolutionary interpretation of what is going on each side is struggling to outwit the other because on both sides those individuals who succeed will automatically pass on the genes that contributed to their success ideas of futility and waste spring to our minds because we are human and capable of looking at the welfare of the whole ecosystem natural selection cares only for the survival and reproduction of individual genes now finally the last chapter is called there is grandeur in this view of life which you'll recognize as a quotation from darwin it comes from the very last paragraph of the origin of species and my last chapter takes each sentence of darwin's last paragraph and makes each sentence into a section heading of my last chapter and the body of the section is an exegesis of that sentence of darwin the last sentence of darwin's book is endless forms most beautiful and most wonderful have been and are being evolved and i'm going to read the last page of the book in conclusion the fact of our own existence is almost too surprising to bear so is the fact that we are surrounded by a rich ecosystem of animals that more or less closely resemble us by plants that resemble us a little less and on which we ultimately depend for our nourishment and by bacteria that resemble our remoter ancestors and to which we shall all return in decay when our time is passed darwin was way ahead of his time in understanding the magnitude of the problem of our existence as well as in tumbling to its solution he was ahead of his time too in appreciating the mutual dependencies of animals and plants and all other creatures in relationships whose intricacy staggers the imagination how is it that we find ourselves not merely existing but surrounded by such complexity such elegance such endless forms most beautiful and most wonderful the answer is this it could not have been otherwise given that we are capable of noticing our existence at all and of asking questions about it it is no accident as cosmologists point out to us that we see stars in our sky there may be universes without stars in them universes whose physical laws and constants leave the primordial hydrogen evenly spread and not concentrated into stars but nobody is observing those universes because entities capable of observing anything cannot evolve without stars not only does life need at least one star to provide energy stars are also the furnaces in which the majority of the chemical elements are forged and you can't have life without a rich chemistry we could go through the laws of physics one by one and say the same thing of all of them it is no accident that we see dot dot dot the same is true of biology it is no accident that we see green almost wherever we look it is no accident that we find ourselves perched on one tiny twig in the midst of a blossoming and flourishing tree of life no accident that we are surrounded by millions of other species eating growing rotting swimming flying walking burrowing stalking chasing fleeing outpacing outwitting without green plants to outnumber us at least ten to one there would be no energy to power us without the ever escalating arms races between predators and prey parasites and hosts without darwin's war of nature without his famine and death there would be no nervous systems capable of seeing anything at all let alone of appreciating and understanding it we are surrounded by endless forms most beautiful and most wonderful and it is no accident but the direct consequence of evolution by non-random natural selection the only game in town the greatest show on earth thank you very much i'm very happy to take questions i think that this mic needs turning on no yeah okay um so i think there are intelligent designers at work they're called molecular biologists and i was wondering if what do you think uh the implications are for the course of evolution of our ability to modify plants and animals and us eventually intelligent designers have been around for a long time of course long before molecular biologists because it was intelligent designers who made brussels sprouts and pekineses and and and um domestic roses um so all that's new is that instead of only having control over the selection part of the darwinian process we now have control over the mutation part as well we can cause genetic changes whereas before we simply had to wait for them to happen so that's that is a big difference and it is already um making having dramatic impacts on our control over the evolutionary process but it's been we've had a fairly good control over it for a long time starting with inadvertent control and moving on to the more systematic and deliberate control of scientific agriculture and horticulture and and plant and animal breeding a lot of scientific innovations have led to a better understanding of anomalies and discrepancies um for example the general relativity finally explain the description is that my con oh sorry i'm not close enough sorry i was that again um a lot of scientific innovations have led to a better understanding of anomalies and discrepancies for example the general theory of relativity led to a better understanding of the discrepancies of mercury's orbit we have plenty of anomalies left in science such as dark manager dark matter dark energy the pioneer anomaly lucid theory of everything that kind of stuff um what discrepancies do you think would lead to if we investigated them more would lead to a better understanding of evolution yeah that's a very interesting question i think that particular model of the history of science works very well for physics it's not easy to see quite how it would work in in evolutionary science i suppose you might say that the theory of uh punctuated equilibrium could be regarded as an example of that where the um the discrepancies that were observed were apparent departures from the expectation of gradualness towards the view that um that the the apparent gaps in the fossil record might not be the actual gaps it might actually really represent a genuine punctuation event i don't favor that theory as much as some people do i think it probably works in some cases um anyway i don't need to go into that now um that might be one possible example um there probably might be others i'd need to think about that thank you thank you thank you for an engaging talk uh darwin considered changing the term natural selection to natural preservation i believe i read in a letter of his uh what would be the implication to the greatest show on earth with the concept of natural preservation over selection darwin was was worried and wallace was even more worried by the implications of the word selection which seemed to many people to imply deliberate selection i mean the word selection i think that was the problem and this was why wallis urged darwin to adopt spencer's term survival of the fittest which again is like natural preservation it's it conveys a more passive view of the process um wallace said that to him and to darwin himself the idea of natural selection was as plain as daylight but to many people it was not and to many people and it's undoubtedly true that in victorian times people did think that there had to be some kind of selector they just couldn't quite grasp the idea that it really was just preservation it really was just the uh survival of the fittest i i'm not sure that many people have that problem now i think people have have other problems now um survival of the fittest gave rise to all sorts of other confusions which which um i think are even greater than the confusions that the victorians saw in in natural selection hi uh do you defend the do you think uh life has a natural tendency to get more complex with time or there it's just random like if we all go extinct in 100 million years another intelligence species will show up or right i don't think it'd be right to talk about an intrinsic tendency to get more complex um it probably is true that natural selection under the right conditions and i think especially of arms races will make it things get more complex there's no law that it has to get more complex um there are i mean parasites are the famous case where they tend to get less less complex um so there's no drive to become more complex there's no urge to become more complex but when you have predators chasing prey and prey running away from predators then you tend to get more complexity to a prodigious extent i mean the complexity of of of a mammal um or indeed a bird or a reptile is is gigantic and i think you can largely put that down to um competitive arms races with with enemies but it's not an internal drive to get more complex evolution and natural selection seems so elegantly simple especially compared to relativity or quantum theory so i'm wondering if you're ever surprised that it took until the 19th century for the theater it surprises me hugely i mean when i compare what darwin achieved to what newton achieved two centuries earlier it seems to me that what darwin achieved should have been a doddle compared to what newton achieved and yet it took two centuries longer and i've often wondered what it was that made it so difficult to get it you certainly don't need to be a mathematician to get it um it came independently to two english traveling naturalists it evaded great thinking philosophers and mathematicians down the ages anybody could have thought of the idea from an armed chair from the time of the greeks onwards they never did or not properly ernst meyer who died only a couple of years ago the age of 100 thought that the stumbling block was what he called essentialism philosophical term um which in conveys the idea that animals and plants are have a kind of essential haven't have an essence which is as fixed and unalterable as for example the essence of a triangle triangle and it comes from the greeks who were geometers at heart and a triangle is a figure with a fixed definition a triangle is a triangle is a triangle it's a it's a polygon with three sides um and people seem to to see rabbits and rhinoceroses as though they were triangles and incapable of changing into anything else it's not clear to me why they should have thought that but that was that's maya's diagnosis that people could see how you could get kind of minor changes within rabbit kind but the idea of extrapolating those minor changes until a rabbit turned into something quite different you no longer call a rabbit even a fish turning into a human after a sufficient length of time that seemed to be beyond people maybe because the sheer time it takes is greater than people can grasp we're so used to the idea that rabbits are rabbits that we don't live long enough to see them turn into anything else but it is a it's a real mystery why um the achievement of darwin which seems so simple took so much longer or maybe it was that the the achievement of darwin which was to show that you can get from without any design at all that you can produce structures so complex that it seems like utter and complete common sense they must have had a designer maybe that is so far from common sense that it that that people who had the intellect to do what darwin did just it just wouldn't even even occurred to them to even doubt the possibility that something as complicated as a brain or an eye or a heart um could have had no designer um excuse me so lateral gene transfer is challenges your ideas that all genes in the same organism have the same evolutionary history and creationists have been using this to say well since we can't know the true tree of life that obviously something's wrong and i'd wonder if you could address that and when you were going to address that in a book of yours um there was a an issue of new scientist which appeared earlier this year with the dramatic headline darwin was wrong you can imagine how the creationists use that uh it turned out if you actually read the article that it was nothing to do with darwin being wrong what it was about was lateral gene transfer what it was about was that in some organisms almost all of them microorganisms bacteria genes move sideways they don't stay in longitudinal lineages like they do in mammals and birds and most of the larger creatures that darwin himself was from was familiar with now it is true that if you look at bacteria you no longer get the nice simple rule that says every gene comes down from parents grandparents great grandparents great great grandparents and so on because we have that rule in the animals we're familiar plants that we're familiar with the the tree of life is a simple branching tree it never meets branches once they've separated once the species has split into two and there's a little bit of a sort of fudge going on while they're splitting when some kind of cross breeding becomes possible is is possible remains possible once they're split sufficiently far apart they no longer interbreed and there is never again any lateral gene transfer from that from then on the tree of life goes on branching and branching and branching without any anastomoses without any networking without any crossing over that's not true of bacteria in bacteria they promiscuously and liberally adopt a kind of copy and paste policy with respect to genes bits of genome were just simply copied from one bacterium and pasted into another one with abandon um and so it's true that at the the root of the tree of life where we have bacteria it's as i think dan dennis said it's more like a banyan tree than an oak tree uh it's it's got um a massively um crossing gene gene transfer so you've got to do a special trick when you get to the bacteria you no longer think of individuals as gene machines that are struggling to pass on their genes longitudinally down through the generations however the the idea of the selfish gene still works a treat the selfish gene is simply trying to maximize its own propagation into the future and if it can do it by copying and pasting itself into another bacterium so much the better so not only was darwin not wrong because darwin didn't know about bacteria dawkins wasn't wrong because at the level of the selfish gene this is a this is a happy hunting ground for selfish genes is is dashing around from from bacterium to bacterium um like quicksilver uh that's wonderful stuff for the for the selfish gene yeah um i uh i have a hundred questions but i just limited to one so i read the new york times review of your book by nicholas wade and he actually took you to task was largely a positive review but he took you to task for asserting that evolution is a fact and as a technical point he made an argument that it's a theory and then actually accused you of um having a uh i'm not sure if i get this right but i think it's a lack of appreciation for the cognitive nature of science yeah uh which is um i was insulted for you but uh yes um i'm yes um nicholas wade was was i have to say very unfairly treated by the commenters to my website richarddawkins.net where we posted this um he he really got a bit of a drubbing there um it i think it boils down to the difference between uh what philosophers of science say where you wouldn't wish to say that anything was a fact i mean you would you would wish to say that that everything that we ordinarily call a fact is just a hypothesis that hasn't been disproved so um it is not a fact that the world is round and not flat um it is a hypothesis that has never been disproved now as stephen jay gould said there does come a point where that kind of cow tying to philosophy of science needs to sort of merge into a bit of common sense and the way he put it was there comes a point where it becomes simply perverse to say well we're still waiting to see if this hypothesis is going to be disproved um the hypothesis that the world is round and not flat is never going to be disproved and the same i would maintain is true of evolution so while it's while it's right to say that philosophers of science would prefer not to use the word fact because the word theory is so wantonly misunderstood by laypeople egged on and abetted by creationist propaganda we are better off using a word that ordinary lay people understand such as fact because we're using the word fact in exactly the same way as for example a court of law would use the word fact if a lawyer whacked his finger at you and said is it or is it not a fact that you were in new york on the night of september the 24th you would not say well it's a hypothesis that's difficult to disprove or something of that sort um you would you would answer the lawyer would have you on toast if you said something like that you would have to answer either it's a fact or it's not a fact that's the sense in which evolution is a fact the same as the fact that i'm standing at a at a wooden lecture in new york city hi um it seems like we're making good progress as a species in a society we're not we don't think that the earth is the center of the universe and we're not like using leeches anymore to treat people well some people are but um um and in our country you know we're moving towards being allowed to do stem cell research but at the same time we've got like sarah palin and like we had a president who said that the jury was out on evolution so do you think that we really are moving in the right direction overall and are these things just sort of setbacks that we shouldn't lose yes i do think setbacks are good word i i think what what we have is a is is a is a progressive movement which is not steady but has a kind of sawtooth effect to it um there's politics going on here of course when something like the sarah palin phenomenon is probably not really about scientific truth it's probably about um political what shall we say grievances maybe there's a sort of inferiority complex among um people who who don't have a very good education against people who do i suspect there may be something like that going on here but i am enormously encouraged as i go around the country and i tend to make a point of going to places not like new york i mean i tend to go to places which are the so-called bible belt and i'm hugely heartened by the warmth of the reception that i get in places like oklahoma and kansas and alabama great big crowds cheering and i think that's because they feel beleaguered i think it's because they they find that somebody coming in from the outside who can say what he likes because he's flying out of the next plane um and and yet and they hear somebody articulating what they feel but perhaps are intimidated from saying because they don't want to be ostracized at the golf club or whatever it might be and and people say that to me in the book signing queue over and over again they thanked me for kind of saying thank you for coming to kansas um we needed to we needed somebody to say what what you've just said this is what i feel and they suddenly notice a whole lot of other people in the hall thousands in some cases and they recognize that they're surrounded by people admittedly they're in a minority but but they can see that they're not alone and i think that's leading to a change i think you see it on the on the internet i think it may be leading to a sort of critical mass phenomenon whereby once the the numbers of such people grow beyond a certain point it'll suddenly go and and you'll suddenly notice a dramatic change this is less of a biological question more of a philosophical one but i think there's a biological slant to it so do you subscribe to the theory of determinism or do you think there's any biological evidence that indicates free will in humans or animals um determinism um in the in the philosophical sense of whether every event that happens in the in the universe indeed is determined and in principle predictable from earlier events is not a question which a biologist needs to answer separately from philosophy or physics this is a more general question physicists may answer using the idea of quantum indeterminacy and that might be relevant to biology if quantum indeterminacy affects biological events such as whether whether or not a nerve cell fires at a particular moment or not um i don't have the expertise as a philosopher to say whether it is right that all events in the universe are predetermined by by other events and certainly being a biologist doesn't give one any right to to make such a thing what i can say as a biologist is that the the idea of genetic determinism which is a much more restricted meaning of the word determinism the idea that everything about us is determined by our genes is uh not justified by the facts and is nothing whatever to do contrary to many critics nothing whatever to do with the theory of the selfish gene the theory of the selfish gene has been widely misunderstood as a deterministic as a genetic deterministic theory misunderstood by those many people who have omitted to read the rather large footnote to the title of the selfish gene which is the book itself hi dr dawkins that was a great talk um my question also was a little bit philosophical um as specifically the extension of evolution beyond uh biology into uh uh a term you coined an uh an idea that's often attributed to you and that's memetics um it seems like you've been a little or from what i've read a little bit hesitant to endorse the idea um i i know you're not you know you're not you're not against it or anything i read your forward and susan blackburn's book but i was wondering uh if you had uh what what reasons you had um or why you weren't such a problem my hesitancy is just that i was never intending to offer a theory of human culture that would have been presumptuous coming from a biologist what i was trying to do at the end of the selfish gene was to downplay the importance of the gene as the only unit of natural selection the whole of the rest of the book emphasized the gene as the unit of natural selection because genes do have certain very important properties namely high fidelity self-replication and a powerful influence over the world which affects their own probability of being replicated namely through phenotypes and so in ordinary biology you cannot do darwinian theory without talking about genes however a generalization of darwinian theory such as might take it to other planets for example would look for any kind of self-replicating information which had those same properties of high fidelity coupled with the ability to exert power over the probability of self-replication and i speculated that on other planets if there is life it will be darwinian life but it probably won't be dna-based life um it'll probably be some other kind of self-replicating coded information and then i suggested to make it easy to understand maybe we don't need to go to other planets maybe we've got one staring us in the face on this planet and that was where memes came from maybe the sort of soup of human culture which is all our brains interacting with each other and passing information when we copy when we imitate when when information flows from one brain to another is it possible to identify units of information being transferred which have high fidelity and which perhaps have power over their their probability in this case being imitated being and i think they are i mean i i mentioned things like tunes that people whistle in the street and that other people pick up you catch it like a virus and you and you hear this damn tune and it goes around in your head and you can't get rid of it um and so you whistle it and somebody else hears it and he whistles it and somebody else hears it and whistles it and it will spread through through a whole lot of a lot of people and the same could be true of all kinds of things clothes fashions not not just in humans i mean habits great tits in in england um when we had milk bottle delivered on doorsteps learned individual genius great tits and blue tits learned to open the milk bottles and then others watched them and imitated and it spread literally like an epidemic you could actually trace this this habit non-genetic it's entirely non-genetic spreading like an epidemic like a measles epidemic around the country through various focal points um natural selection theoretically could work on replicators of of that kind and and in that case we would have memetic selection memetic evolution excuse me my question is actually more of a comment or observation sometimes i feel that part of the problem with the lay public not understanding evolution is that we evolutionary biologists don't always give a complete answer so for example when asked to explain evolution we usually go into something that explains natural selection and give an example like the industrial melanism loss or antibiotics or pesticides but at the end of the day you've still got moths or bacteria or insects and it seems like that what we usually forget is that in the in the process of speciation you need to have geographic isolation producing reproductive isolation and we oftentimes leave that out and we oftentimes do but i'm happy to say i didn't yeah i i i i and you're absolutely right and i didn't talk about peppered moths at all and what we need are more examples of the speciation process than just not yes i take your point good yes professor dawkins um the extraordinary similarities between ourselves and other species that evolutionary biology helps us understand do you think it has an ethical implication in terms of our treatment of non-human animals i mean in my understanding you are not a speciesist i think it does have ethical implications if you think about the way in which we give special treatment to humans for example in the case of abortion um human human fetuses are treated as babies and a lot of people think that it's murder to abort a human fetus whereas they quite happily go eat a cow which of course has much more capacity to suffer than any human fetus does now evolution immediately has an impact on this debate because if you think going backwards through evolution at some point we are connected to cows i mean i just did it i did it earlier but you could do it for any pair of animals you like chimpanzees which are pretty close to us are not given anything like the same ethical um moral legal protection as as humans are what would we do what would those speciesists do if a live specimen of lucy of australopithecus afarensis were to be discovered would we have and suppose all intermediates were available suppose there were um there were discovered relic populations in the forests of africa between humans and chimpanzees all the way up into the hairpin and back down again so close to each other that it would be possible for a human to interbreed with an intermediate who could interbreed with the next intermediate who could integrate with the next and so on who could finally interbreed with a chimpanzee how would you police how would you decide on the ethical dis discrimination between humans and chimpanzees would we have south african style apartheid courts to decide whether lucy passes for human for example immediately now it's a fortunate from one point of view fortunate accident that those intermediates are all now extinct but if they weren't extinct we couldn't do the sort of speciesist discrimination that we do and that that fact that they might not be extinct should immediately give an uneasiness it's a pure accident that they're extinct we ought to be able to to do something about our morals and our ethics taking account of the fact that they might not have been extinct it shouldn't this this major ethical distinction should not depend upon the mere accident of extinction oh hi dr dawkins i'm a big fan um i have most of the elders in my family who are like myself devout christians um how do i um and they also uh don't really believe in evolution how do i convince them to read your book or at least consider evolution without making a personal attack on their faith um it shouldn't seem like a personal i mean it's not only a personal attack on their faith a personal attack on somebody's faith is often interpreted as a personal attack on them it it has a deep emotional wounding effect it's like saying they have an ugly face or something like that um so it's very difficult i mean i think you can only reason and say look the disagreement is a mere disagreement about cosmology about about biology why should this be such an immense barrier why should you resist so strongly when you don't resist an argument about the quality of a piece of music or the quality of a football team or the quality of a play or the quality of a book but when it comes to religion you suddenly feel all emotionally bound up with it um i should have thought that wouldn't be beyond the grasp of of of most people um i i but it i admit it is very very difficult and i wish you luck in your endeavor uh you know dogs in world and wolves still can interbreed uh looking back at the point of bifurcation in development of new species all the species that are defined species lose the ability to interbreed so is there some sort of a common process in all of life that says once you reach a certain point you can't integrate yes yes it happens it happens at first when the when the chromosomes of the two if you if you take a hybrid like say a hybrid between a donkey and a and a horse a mule or a or or a or a hinny um the the the the cr the chromosome the the genes can still work to produce an animal and then a mule is a perfectly um strong and fit an animal but when it comes to make sperms or eggs uh the the chromosomes need to come together in order to uh to perform the process of meiosis and if there's a sufficient difference between the chromosomes as there is between horses and donkeys then the chromosomes can't come together in meiosis and so the animal cannot make gametes it can't make viable sperms or or eggs that's the first thing that happens the later thing that happens is that the animals don't even want to mate with each other because they look too different or smell too different so it is a gradual process it doesn't there's not there's a sudden curtain comes down it says right you're now separate species you can't interbreed what happens is it's usually in geographical isolation the ancestors of horses and donkeys would have been split by some kind of geographical barrier and they would have drifted apart or maybe been selected apart um sufficiently far that they that when they met again they they either didn't want to breed again or couldn't breed again into interbreed again and that's the point where biologists come along and say okay they're now a different species it is a gradual process but once it's happened it's never reversed i think thank you very much dr dawkins i just want to say thanks for taking our questions thanks for great questions i appreciate it and keeping the time richard dawkins is a professor at oxford university he's the author of the selfish gene and the god delusion for more information visit richarddawkins.net among other titles tina brown is the co-founder of the

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Published: Mon Jul 16 2012