Participants:
Series Code: EI
Program Code: EI190002S
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00:36 Hello, I'm Dr. Sven string.
00:38 Welcome back to Evolution Impossible. 00:41 Here with me to continue this fascinating 00:43 journey is Dr. John Ashton, 00:45 Ellie Turner, Jeandré Roux, and Stephen Aveling-Rowe. 00:49 Thanks for joining me once again. 00:51 As soon as I say the name, "Darwin," 00:53 I'm sure that you'll instantly know who I'm talking about. 00:57 And pictures of the voyage of the HMS Beagle, 01:00 the Galapagos Islands, finch beaks, 01:03 and that very well known picture of a line-up of monkeys 01:06 slowly standing up and gradually becoming a human being 01:09 will come to mind. 01:11 But sometimes people really don't know 01:14 what Darwin's theory actually was. 01:16 So, John, can you clarify for us, what was Darwin's theory? 01:21 How did he explain how life came about? 01:24 Yeah, sure, well Darwin grew up in the age when we had 01:29 the mechanical world view was being developed, 01:32 and in particular machines were being developed. 01:36 - It was very mechanistic. - Well, yes. 01:38 But machines were evolving. 01:39 And there was talk about these changes, 01:43 and people were actually saying, "Well, did life 01:46 actually change like this too?" 01:47 Because there was also a group of intellectuals 01:50 that believed that the earth was millions of years old. 01:53 So James Hutton back in the late 1700's had proposed this, 01:58 that the biblical timeline was too short, 02:01 that the rocks were millions of years old, 02:03 and that time was much longer. 02:05 Now the other thing was that Darwin, of course, 02:07 was very interested in nature. 02:10 And he'd been interested in breeding, and so forth. 02:13 He was very interested in beetles, if I remember rightly. 02:15 Is that correct? 02:17 Well, that was among the many different types of animals. 02:20 He was interested in lots of animals. 02:21 Part of this initial concept, though, came from 02:24 studying, for example, just grass in the lawn. 02:28 - Watching grass grow. - Well, yes. 02:30 But what he noticed was that when he looked at 02:33 a square yard of grass... 02:35 And they had yards back in those days, 02:37 Meters today. 02:38 ...that there were all these different types 02:41 of grass in there, and they were essentially competing 02:43 for the same space and the same nutrients. 02:46 And this was, in his mind, there was competition here. 02:51 Now at that time, as well, he went on the voyage 02:54 on the Beagle, that we learn about, and he 02:57 was given a copy of the book by Charles Lyell, the geologist. 03:02 Now Lyell, again, was certainly enamored with long ages 03:07 and long periods of time. 03:09 And so, Darwin read this book. 03:13 Now in the meantime, Darwin was putting together 03:15 his ideas of how perhaps mutations produced 03:21 different types of organisms. 03:22 And he drew a tree, a tree of life. 03:25 And he proposed that... 03:28 He saw this piece of grass, and many of them were so similar. 03:31 So he thought, well maybe there are mutations. 03:34 And they breed, and they breed, and then over time 03:36 after enough generations of sufficient differences 03:40 that they actually form a new species. 03:42 So how many generations does it take for that tree 03:45 to start branching? 03:46 Well, Darwin didn't know, of course, but he proposed 03:50 initially in his diagram, and as he wrote about it, 03:52 about a thousand generations. 03:54 But he also made the proposal, well maybe it 03:56 could be ten thousand generations. 03:58 So he didn't really know. 04:00 Which was quite reasonable, you know, 04:02 in terms of developing his theory. 04:04 So essentially, when he read Lyell's book on the journey 04:09 and saw that Lyell had noticed that in the fossil record 04:13 the fossils higher up in the stratum, 04:16 which was the more recent strata, 04:18 seemed to be more complex compared to the animals 04:21 that were further down. 04:23 This sort of matched Darwin's little diagram 04:26 of his tree of mutations. 04:29 And essentially, that's what he did. 04:30 He put the two together. 04:33 And of course, he noticed in that island off the 04:35 west coast of Africa, Madeira, I think it is, 04:38 that there were a couple hundred species of wingless beetles, 04:41 and they had survived, because it's a very windy island. 04:44 And of course, the beetles that have wings 04:46 just got blown off the island. 04:47 So they didn't stay around to mate and breed. 04:50 But the ones that developed deformities, had mutations, 04:54 and so their wings were smaller, they didn't get blown off. 04:56 So they can breed and progress. 04:58 So the beetles were evolving. That's what he was thinking. 05:01 Yes. And so that led to this idea of survival 05:05 of the fittest for the environment. 05:06 So that eliminated the mutations that weren't suited. 05:11 So the best mutations survived. 05:13 So it's a combination of those three factors, really. 05:15 The competition of species, saw them there, 05:18 but there were a lot of similarities with the grass. 05:20 So maybe there was a common ancestor, and they all 05:23 sort of bred and slowly developed differences; 05:26 represented by that little tree. 05:28 And then Lyell's theory; well hang on, we've got all these 05:31 different layers in the rocks, and they contain different 05:34 types of fossils, it would seem, in varying complexity. 05:38 And then this observation of many species competing 05:42 for food, or in the environment, and so forth. 05:45 I mean, it was a brilliant idea he went through. 05:49 One of the things, of course, was he didn't 05:51 know how life started. 05:53 He said, whatever, some primordial ancestry 05:56 into which life was first breathed. 05:58 So that common ancestor going back in time 06:01 through this tree of life. 06:02 That's right, yes. 06:04 And look, this tree of life, it's a brilliant teaching tool. 06:07 You know, in terms of you just draw it out there on a notebook, 06:10 or on a blackboard back then. 06:13 And I guess my question for our panel here is this: 06:16 Does Darwin's tree of life, does it make sense to you? 06:20 Does it, you know, does it kind of explain, 06:24 do you get what Darwin was trying to say? 06:27 Yeah, absolutely. 06:28 I mean, for me, the twigs on the branches, they make sense. 06:32 But the branches and the trunk itself, that's where 06:35 I struggle to see the connections. 06:37 Right, right. 06:38 So you start to doubt the history 06:41 of this very tree of life. 06:43 Seeing the record there, I just haven't seen enough evidence 06:46 for me to personally say that it makes sense. 06:48 Right. And what about you, Jeandré? 06:50 Yeah, yeah, for me it's very vague. 06:52 Like, he draws this tree of life, and he explains it, 06:58 but he doesn't really know anything. 07:01 It could be a thousand years, it could be 07:03 a thousand generations, you know. 07:05 He's just vague. 07:07 And I guess the big question, John, is this: 07:10 Was this the only theory around? 07:13 And Ellie, just wanted to know, did you have any questions 07:16 for John on that topic? 07:19 Yeah, I was specifically wondering what other theories 07:23 in the western world existed in the time of Darwin, 07:26 in terms of the origin of life? 07:29 Obviously there were lots of religions around the world 07:32 that believed different things about how life originated. 07:35 But was it widely believed in Darwin's time that God 07:38 created the world and the things that we see? 07:41 Or was there other theories that were circulating? 07:44 No, certainly in Darwin's time at leading European universities 07:51 most leading scientists and philosophers would have 07:53 believed in God and creation. 07:56 In fact, flood theory to explain the origin of structures 08:00 was probably taught at Oxford University up at least until 08:05 the early 1800's. 08:08 So these scientists certainly believed in that. 08:11 And many of the leading scientists 08:13 were, in fact, creationists. 08:14 You know, people like Newton. 08:16 And even after Darwin's time, there were scientists that 08:20 recognized, hang on, there are major problems with his theory. 08:23 And one of those scientists is James Clerk Maxwell. 08:26 And Maxwell was the physicist that proposed that life was 08:32 a combination of electric and magnetic fields. 08:35 He developed field theory. Brilliant physicist. 08:37 Matter of fact, Einstein simply applied his theories 08:40 to gravity and built on Maxwell. 08:41 So Maxwell is one of the great scientists, 08:44 along with Einstein and Newton. 08:47 And Maxwell is a very strong anti-Darwinist. 08:50 And he would say, "Well, how did molecules evolve?" 08:53 And, "How did atoms evolve?" 08:55 He raised a lot of very interesting questions. 08:58 But in actual fact, the theory of evolution goes back 09:01 to the ancient Greek times. 09:03 So you've got Greek philosophers living about 09:06 500 BC, that sort of era, Democritus, and so forth, 09:10 they believed that, they didn't believe in God; so atheists. 09:15 And so they believed originally that matter, 09:17 there were just all these little particles of matter, 09:20 and they float around and they come together, 09:23 and they became the animals, and the trees, 09:26 and this sort of thing. 09:27 And those theories were recorded, I recall, in a poem 09:33 by Lucretius, a Roman poet. 09:37 He wrote around the first century, I think, 09:41 or there abouts. 09:42 And his poem was essentially lost and rediscovered. 09:45 And again, boy, you're testing me on my history now. 09:48 But I think round about the 1300's a copy of Lucretius' poem 09:53 was discovered that encapsulated these earlier theories 09:58 of Democritus and so forth, in terms of atoms and so forth. 10:03 And that really led to an explosion of thinking 10:07 along these particular lines and laid the foundations later 10:12 for evolutionary theory. 10:13 Of course, in the meantime there had been these theories 10:15 of, you know, that life was spontaneously generated. 10:19 You know, people had noted, well hang on, 10:21 if you leave a bag of wheat out, or something, you know, 10:24 you'd find mice there. 10:27 But Pasteur, again, was able to show that, hang on, 10:33 if you boiled a liquid and sterilized it, 10:38 and separated it from air, you didn't get anything 10:43 coming to life or grow. 10:45 So even today, of course, we still don't know how 10:49 the first life, you know, started. 10:51 Darwin's theory really provided a mechanical 10:55 theory based on a mechanical model. 10:59 Because at that time, Newton had published his 11:03 principle of mechanics and the laws of motion. 11:07 The laws of physics had been discovered. 11:09 But biology was out there by itself. 11:12 So now if you had the tree of life, you had your mutation 11:15 mechanisms, your natural selection. 11:17 You had this mechanical mechanism now 11:20 that could be applied to biology. 11:23 So that's why it really, really took off. 11:25 Plus, Lyell was a brilliant geologist, 11:29 and he did a lot of mapping, he developed this concept 11:32 of the geological column over time. 11:35 And that was embraced too. 11:37 The only issue was that a lot of the measurements 11:40 that he did were based on estimates and so forth 11:44 that we know now are wrong. 11:48 And so, from what I understand, Darwin's grandfather, 11:50 Erasmus Darwin, actually believed in a 11:54 form of evolution as well. 11:55 And he had a colleague, Wallace, if I recall correctly, 11:59 who was also developing these ideas. 12:01 So, there is this real fascination with machines, 12:04 but also this real emphasis on how do we kind of 12:09 eliminate or push these supernatural out of the 12:14 developmental process for life as well. 12:16 So it's very interesting, this whole year in which these 12:20 theories were developing. 12:22 But of course, Darwin had a friend, a colleague, 12:25 Thomas Huxley. 12:27 And can you tell us a little bit more about Thomas Huxley 12:30 and his involvement with Darwin and the promotion 12:34 of the theory of evolution which followed from Darwin's book? 12:38 Yeah, so Huxley wrote a book three or four years after 12:44 Darwin, it would have been published 1864, I think. 12:49 Something like, The Ascent of Man. 12:52 Something like that. 12:54 And essentially, his claim was that man had 12:59 ascended from the apes. 13:00 And so he applied Darwin's theory of evolution, 13:04 particularly in the concept of the origin of man, 13:07 and that man has essentially evolved from apes. 13:11 And that's, of course, why anthropologists and 13:13 paleontologists began looking for the earliest, you know, 13:18 remains of human-like species in Africa. 13:21 That was the whole basis of that because apes 13:24 were found in Africa there. 13:27 So that was a very important aspect. 13:29 And my understanding from the reading of literature is, 13:32 that whole mid-1800 area was so enamored with this 13:40 mechanical view of things. 13:42 And they were certainly talking about, you know, 13:45 in academic circles, machines, and they saw the gradual 13:50 evolution of the steam engine and people with better valves, 13:54 and better safety valves, and you know, so forth, 13:58 develop better machines. 13:59 But at the same time we also, with the industrial revolution, 14:03 saw people moved off their little cottage industries 14:06 into the cities, and there wasn't there enough work now, 14:09 there wasn't enough food, and so there was intense competition 14:13 for survival in the cities to get enough food. 14:16 So there was all this social change that you talked about 14:20 taking place, where you saw that in society. 14:22 People were fighting over the limited resources in the city. 14:26 And at the same time there were all these machines evolving, 14:29 powering the cotton mills, people with better governors 14:32 on their machines, and better horsepower, 14:34 and could produce more. 14:36 And so those factories did better, and the other ones, 14:39 you know, sort of went broke, and this sort of thing. 14:41 So it was a whole environment at that time. 14:44 At the same time, the power of the church was very strong, 14:48 and there were a lot of academics that didn't want 14:51 and were looking for ways to challenge 14:53 the power of the church. 14:55 And Darwin's theory was seen in this way, hang on, 14:58 we can explain the origin of life outside the story 15:03 or the account in Genesis. 15:06 And this had really gripped that group of academics 15:09 that didn't want God in the picture. 15:11 And that would explain the debate between the bishop 15:14 Samuel Wilberforce, Thomas Huxley, 15:17 and also Charles Darwin as well. 15:19 One of the comments they made is, you know, 15:22 whether they evolved from a monkey or an ape. 15:26 You know, whether their grandmother was an ape or not. 15:29 And I guess the question for us today is this: 15:31 How do you feel about this concept of us evolving 15:35 from some kind of ape-like creature in the past? 15:39 How does that strike you? 15:41 I've always struggled with the idea that my 15:43 great great great grandfather was a monkey. 15:46 But I actually had a specific question for Dr. Ashton on that. 15:50 In chapter two of your book you mentioned the find of a skeleton 15:55 that they call, Lucy. 15:57 And that was suppose to be a transitional fossil 15:59 between humans and apes. 16:01 And you noted that since then, there has been more recent 16:05 finds that Lucy was actually more different 16:08 from humans and apes than humans and apes are from each other. 16:13 And I was also wondering what that find exactly was based on. 16:17 Was it based on the skeleton structure, or was it based on 16:21 DNA evidence, or how did they come to that conclusion? 16:24 Yeah, so it's certainly based on anatomical evidence. 16:27 So it was based on the physical bone structure and so forth 16:31 when that was examined. 16:33 It's interesting, in museums that sometimes have models 16:37 of Lucy, and one of the ones that I saw would have been like 16:42 a typical human model where they put hair all over her 16:47 and put sort of an ape-like face. 16:49 But humans stand very different to apes. 16:54 We have a very different pelvic structure, 16:56 the way the bones enter there, and so forth. 17:00 And it's very different. 17:02 And so what happens is, sometimes in these museums 17:06 and in these reconstructions that are portrayed in books, 17:10 they're portrayed it would seem more human-like 17:13 than in actual fact they are, if we actually portrayed them 17:16 as they are correctly anatomically. 17:19 They wouldn't look as human-like as they're portrayed. 17:22 And of course, this all helps confirm this concept 17:26 that we did evolve from apes. 17:27 Where in actual fact, when we look at the actual physiology, 17:30 when we examine the bones, when we examine how they 17:32 would have stood, it would have been very different to those 17:34 images that are created. 17:37 So carry on from that then. 17:38 Think of living fossils. 17:40 I mean, how, within evolutionary millions of years, 17:44 would we still have fossilized remains of things like, I mean, 17:48 there whales, there's so many different species 17:50 that we have exact conformity to what we see 17:53 in the natural world today, and yet, if we look back 17:56 you know, there are also fossil records? 17:58 How does that fit in with the evolutionary perspective? 18:01 Well, of course, yes, Darwin claimed that, you know, we would 18:06 find the fossils of the intermediate species. 18:08 This was a major problem. 18:10 And so, what we find in the fossil record is that 18:13 the species essentially don't change. 18:15 They appear, they stay the same, and then they become extinct, 18:19 or we find fossils like, you say, of whales 18:21 and they're the same today. 18:24 What we're not finding is the intermediate. 18:26 So we should have seen slowly, say, the development of turtles. 18:30 We should have seen slowly a creature changing into a turtle. 18:34 Or the development of horns, 18:37 say, you know, on different species, 18:39 whether it's dinosaurs, where we should have seen the 18:42 gradual development of these. 18:43 But we don't. 18:45 We don't find these evolutionary intermediates. 18:48 You know, a classic one is sort of from dinosaurs to birds, 18:52 looking for the intermediates, they're often desperate 18:54 to find a fossil. 18:57 But the point is that if Darwin's theory really happened, 19:00 and we find trillions of fossils just about, 19:03 there should also be millions of intermediate fossils. 19:10 Millions of fossils showing this gradual transition. 19:14 But we don't find those changes. 19:16 This is a major, major problem. 19:18 And leading paleontologists recognize this too, 19:21 that the geologic column doesn't actually show 19:25 the gradual progression that originally 19:28 Lyell thought that it did. 19:29 And secondly... 19:31 In actual fact, the fossils are all mixed up. 19:33 Like, for example, when I was in Hawaii recently 19:35 I saw in the museum there a fossil of a mammal 19:40 with the remains of a dinosaur in its stomach. 19:44 Well, people often think, you know, the mammals came later, 19:46 but no, they coexisted with dinosaurs. 19:48 Now that's not the picture that we often get. 19:51 No, the fossils, in actual fact, are a lot more mixed up 19:54 than they'd have us to believe in the geological column, 19:57 in actual fact, out there. 19:58 And the other thing is, the lack of these intermediates. 20:02 We haven't found the intermediate fossils. 20:04 So the geologic record, the paleontologic record 20:09 doesn't actually provide evidence for evolution. 20:12 And this is a major problem. 20:14 But again, this isn't really enforced to the young people. 20:19 You know, Dr. Ashton, for me it's always been, 20:23 if evolution teaches that we evolved from apes, 20:26 why are there still apes? 20:28 So how does evolution explain that? 20:29 Well, I guess from the tree they would say 20:32 some continue the same, but you have these mutations 20:35 that come off, and they've accumulated, and so forth. 20:40 But another question that follows from that is, 20:42 it's well known that human beings, chimpanzees, apes, 20:47 we're about 96% the same, in terms of our genome. 20:52 That sounds really suspiciously like the fact that we evolved. 20:56 How would we address that, 20:59 that sort of genetic piece of information? 21:02 Yeah, sure. 21:03 Okay, well look, that's pretty subjective. 21:06 That 96%, I guess, looks at the number of genes that are 21:12 responsible for biochemical pathways that we have. 21:14 So, we are very complex. 21:16 Our biochemistry is extremely complex. 21:19 And so, we have a lot of DNA in us to provide 21:23 those biochemical pathways and all those molecular machines 21:26 that are very similar in a lot of mammals, 21:28 and particularly in apes that are slightly similar to us. 21:32 But that kind of similarity doesn't include a lot of the 21:35 junk DNA which they didn't know. 21:37 So there's a lot of questions over that. 21:38 And when you actually look at the code, 21:40 when I look at the code and read it, 21:43 man, it doesn't look similar to me. 21:44 It doesn't look like 96% similarity. 21:46 It looks totally different. 21:48 What they're saying is that there are sections of code that 21:50 switch on similar genes, and so forth. 21:56 But again, to me, if we use the example of Porsche and VW cars, 22:02 you know, they have the same designer. 22:03 They're quite different. 22:05 But they have a lot of commonality, 22:07 you know, common properties. 22:08 You know, horizontally opposed engines 22:10 and rear engines, and so forth, 22:12 because they have the same designer, father and son team. 22:15 So what you're saying is, similarities in terms of anatomy 22:18 and genetics, and the genome, could also be explained by the 22:22 common designer rather than just a common ancestor. 22:25 - That's the designer reasoning. - Ah yes, yes. 22:28 And look, one of the fascinating things is that 22:30 Darwin's tree and the original evolutionary trees 22:34 that were proposed after Darwin based on the fossil record, 22:39 and the geologic column, and the shape of animals, 22:44 their anatomy and physiology, which we call the 22:47 homologous series, of sort, 22:49 that's based on their anatomy and physiology. 22:51 When we started analyzing the DNA, when we got that 22:55 capability, we found, whoa, hang on, 22:57 it's a totally different picture. 22:59 And so when we drew the, what we call, phylogenetic trees, now 23:03 based on the similarities in DNA, they go really wild. 23:07 Like, I think the ones for humans, we're related to dogs, 23:11 and fungi, and E. coli. 23:15 You know, I mean, it just goes really weird. 23:21 And I think one of the things that people don't realize is 23:23 that the same piece of code in a different environment 23:27 will produce different outcomes. 23:30 And this is one of the fascinating things. 23:32 So you can have a code that might produce an eye 23:34 in one organism, and in another organism 23:37 it doesn't produce an eye. 23:39 This is one of the fascinating things. 23:42 And one of the diagrams that you probably would have seen 23:44 in your science textbooks would have been 23:47 this series of embryos. 23:50 So not only the similarities between chimpanzees 23:53 and apes and human beings, but also embryos. 23:57 Following the development, and you start to see, hang on, 24:00 it looks like evolution. 24:02 You can watch evolution in action. 24:04 So I just wanted to know, do you have any sort of thoughts 24:07 or comments or questions on that aspect of evolution? 24:11 Jumping in on that one, I mean, you know, 24:13 Haeckel's drawing that we see was done quite a while ago. 24:17 You know, it's still being in textbooks right into the 2000's. 24:22 What is the evidence to support that? 24:24 And have there been further photographic studies 24:26 done to document that? 24:29 Yes, yes, certainly. 24:30 So, yes, Haeckel, the German embryologist, proposed that, 24:35 that the embryos went through stages that represented 24:38 the evolutionary ancestor of the species. 24:43 And this has certainly been in textbooks, you know, 24:47 up until fairly recently, as you say, in the mid-2000's. 24:50 I remember seeing that purported or written up in a 24:53 textbook at a university in the university library. 24:56 Which I thought was really wrong, because 24:58 back in the mid-1990's Dr. Richardson 25:02 with a team of colleagues did a major study photographing 25:05 embryos from a number of different creatures 25:07 and putting them together. 25:08 And that was published in, Science, in 1998. 25:11 It was published in, The Journal of Embryology, I think, earlier, 25:13 but it got into, Science. 25:15 The journal, Science, is one of the top science journals 25:18 in the world, with, Nature; so if you get published 25:21 in that journal, you get a lot of brownie points. 25:23 So that has definitely been shown to be incorrect now. 25:28 He showed that that does not occur. 25:30 No human fetus' have gills at any stage. 25:35 None of these scenarios claimed by Haeckel actually occur. 25:40 And really, it's morally wrong that those textbooks 25:43 that should really be up-to-date are publishing that now. 25:46 Because that was a major study to investigate that. 25:49 There were multiple authors. 25:51 It was published in major science journals in 1997, 1998. 25:55 And Dr. Ashton, it sounds like such an emotive story, 25:58 and it's so convincing on the surface, but I'm thinking, 26:02 I'm wondering, am I correct in understanding that 26:04 if our DNA is fully human right from conception, 26:09 that it wouldn't be scientific anyway for us to reflect all the 26:14 different evolutionary stages of the past? 26:17 - Is that correct? - Yes, spot on. 26:19 And that's a very interesting characteristic. 26:23 But what makes our DNA fully human is the big picture 26:26 of the DNA. 26:27 And I guess, what upsets me is that today authors are producing 26:33 books for young children. 26:35 I saw one titled recently, I think, Grandmother Fish. 26:38 Something like that. 26:40 And it's teaching young children that they evolved from fish. 26:44 And I think this is just so morally wrong. 26:46 We don't have any mechanism for that, 26:48 we don't have any geological or paleontological 26:52 evidence for that, and yet this is being put into young minds. 26:55 And that really upsets me. 26:57 You know, we really appreciate you just being able to journey 27:00 with us through Darwin's theory to have a better understanding; 27:04 to understand some of the sociological, but also the 27:06 scientific aspects as well. 27:08 And you know, you might have been thinking you wish 27:11 you were here with us to have this discussion together. 27:14 Well, the good news is this, you can actually join us. 27:17 Just go to any online book store right around the world 27:21 and get Dr. John Ashton's book, Evolution Impossible. 27:25 You can go chapter by chapter. 27:27 You can be one step ahead of us. 27:28 Wouldn't that be great? 27:29 But, you know, it's been really good to gain a very 27:31 clear understanding of what Darwin's theory 27:34 of evolution actually was. 27:37 Now that we have a much better grasp of his theory, 27:40 we can start asking the question, 27:42 is evolution impossible, or is it possible? 27:45 Next time we'll be diving into the smallest living thing; 27:48 the living cell. 27:49 Join us on this exciting journey of scientific discovery. |
Revised 2020-02-10