Tag Archives: Darwinism

News

Do non-coding segments of the genome provide evidence for common ancestry?

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From Evolution News.

Excerpt:

Darwin’s tree of life might be visible in DNA, if DNA didn’t conspire to scramble the signal.

Now that quite a few genomes have been published, a team from Australia and France went on a Darwin fishing trip in the gene pool. In the largest study of its kind to date, they examined microsatellite markers (tandem-repeated DNA motifs of 1-6 base pairs) that are widespread in eukaryotic genomes. If neo-Darwinism is correct, these non-coding stretches of DNA should reflect the tree of common ancestry by showing similar mutational patterns in related groups.

Well, they don’t. The paper by Meglecz, Neve, Biffin and Gardner in PLoS ONE is titled, “Breakdown of Phylogenetic Signal: A Survey of Microsatellite Densities in 454 Shotgun Sequences from 154 Non Model Eukaryote Species.” What went wrong?

As the title implies, the team checked 154 “non-model” species. Darwinian evolutionists tend to focus on the model species, like a particular roundworm, the fruit fly Drosophila melanogaster, and a species of watercress, because their genomes are complete and most researchers use them in experiments. Problem: they may or may not be representative:

Although information for model species is accumulating rapidly, it is insufficient due to a lack of species depth, thus intragroup variation is necessarily ignored. As such, apparent differences between groups may be overinflated and generalizations cannot be inferred until an analysis of the variation that exists within groupshas been conducted. In this study, we examined microsatellite coverage and motif patterns from 454 shotgun sequences of 154 Eukaryote species from eight distantly related phyla (Cnidaria, Arthropoda, Onychophora, Bryozoa, Mollusca, Echinodermata, Chordata and Streptophyta) to test if a consistent phylogenetic pattern emerges from the microsatellite composition of these species.

Sounds like a good test. After all, scientists shouldn’t generalize on overinflated signals, right? The team expected to find nicely behaved data interpolated between the model species. It wasn’t to be:

It is clear from our results that data from model species provide incomplete information regarding the existing microsatellite variability within the Eukaryotes. A very strong heterogeneity of microsatellite composition was found within most phyla, classes and even orders. Autocorrelation analyses indicated that while microsatellite contents of species within clades more recent than 200 Mya tend to be similar, the autocorrelation breaks down and becomes negative or non-significant with increasing divergence time. Therefore, the age of the taxon seems to be a primary factor in degrading the phylogenetic pattern present among related groups. The most recent classes or orders of Chordates still retain the pattern of their common ancestor. However, within older groups, such as classes of Arthropods, the phylogenetic pattern has been scrambled by the long independent evolution of the lineages.

There are two ways to interpret this anomaly. One is that microsatellites mutate too fast to maintain the phylogenetic signal. (This is known as a “post hoc rationalization.”)

The other is that Darwin was wrong. Data do not show a phylogenetic pattern; they show common design with some variation.

Read the rest here. I’m a skeptic on common ancestry, but not for religious reasons. I just don’t think that it’s compatible with the progress of science.

News

Hard and soft transitional forms in the fossil record

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Casey Luskin writes about it at Evolution News. (I removed all his links from the excerpts)

Excerpt:

Another good example is what the principal blogger covering human origins at BioLogos, Dr. James Kidder, did last year did in a series on human origins. His series is a good read and quite a competent presentation of the standard Darwinian evolutionary view of human origins — which no doubt reflects Dr. Kidder’s extensive training and experience with this issue. But it accedes 100% to the standard Darwinian story of human origins with essentially no critical analysis whatsoever. But how solid is the evidence behind Dr. Kidder’s view, and are there credible paleoanthropologists who doubt key parts of the orthodox story?

Here’s ONE of the problems that Luskin writes about:

Dr. Kidder’s BioLogos post tried to argue that I misunderstand the meaning of “transitional fossil.” This is a common and characteristically unfounded charge from Darwinian evolutionary biologists. They make the accusation because it takes the focus off the problems the fossil evidence poses for Darwinian evolution, and puts it on Darwin-critics. Advocates of Darwinian evolution also redefine what counts as “transitional,” so that the term becomes nearly meaningless. Here’s what’s going on:

We see that the phrase “transitional form” is used in two different ways. The “soft” definition of “transitional” implies that an organism merely needs to bear features that are representative of a potential intermediate — even if the fossil itself was not a direct transitional form. Under the hard definition of “transitional form,” a stronger claim is made that this organism actually was a real-life lineal intermediate between two taxa, a direct transitional form.

As evidence that this soft/hard distinction is used, for example, when some early tetrapod tracks were first reported in early 2010, Nature‘s Editor’s Summary said: “The finds suggests that the elpistostegids that we know were late-surviving relics rather than direct transitional forms, and they highlight just how little we know of the earliest history of land vertebrates” (emphasis added). The qualified term “direct transitional form” is a nod to the writer’s understanding that there is in fact a “hard” definition of a transitional form, and a “soft” definition, and that some fossils don’t meet the hard definition. What some people call a “transitional form” isn’t necessarily a “direct transitional form.”

So are there direct transitional forms in the hominid fossil record?

If you define “transitional form” in a soft enough way, so that neither temporal placement nor phylogenetic relationship matters any more, then it becomes very difficult to disprove claims that a fossil was “transitional.” It’s a wily rhetorical tactic, designed to make Darwin-skeptics look ignorant while simultaneously taking the focus off the lack of actual (e.g. hard) transitional forms in the fossil record. Dr. Kidder complains that ID proponents define such forms “in such a way that none could ever be found,” when in reality it’s Darwinian evolutionists who define transitional fossils so that they must, by definition, be found in abundance–even if they weren’t necessarily part of an evolutionary transition. Thus we see the Nature blogger quoted above saying absurd things like “every newly discovered fossil of a creature we didn’t know of before IS a missing link.” Or, we see Dr. Kidder making the less-absurd (though similarly inspired) claim that “[t]he human fossil record, in fact, is replete with transitional forms” as well as:

Transitional fossils in the human fossil record are distinguished at both the genus and species level. This group includes the extinct genera Ardipithecus andAustralopithecus and the current genus Homo.

Kidder would have no troubling finding some authorities who agree with him. But there are also credible authorities who disagree — especially with regard to those specific fossils. For example, in my series we’ve seen there are credible authorities who believe that “one of the most critical” areas of the human fossil record lacks transitional forms–specifically, “the transition fromAustralopithecus to Homo.”

Likewise, my series has also cited authorities who would disagree with Dr. Kidder’s claim that Ardi “was advanced in the human direction,” in the sense of developing bipedal locomotion, and who would sharply dispute his assertion that Ardi represents “a phenomenal example of a transitional form in the human fossil record.” Other experts would dispute the claim advanced by Kidder that the australopithecines show clearly “transitional characteristics.” In particular, many doubt theclaim that Lucy’s morphology was “perfectly intermediate between the ape position and the human position.”

Indeed, even Kidder admits: “Unfortunately, the path from Australopithecus to early Homo is shrouded in mystery, with no clear hominin form considered decisively to be the progenitor.” True! But then why does Kidder feel the need to so completely capitulate to the view that humans evolved from Australopithecus? He claims that ID proponents take it as an “article of faith” that transitional forms don’t exist, but it seems that some Darwinian evolutionary scientists take it as an “article of faith” that they do exist, and that the standard Darwinian story of human origins is true.

My point is not that Dr. Kidder is unequivocally wrong or that he’s uninformed. Hardly. He’s welcome to hold and express his opinion, and his series is a highly competent presentation of the standard Darwinian evolutionary account of human origins. Rather, I want to note that the standard story of human evolution — to which BioLogos’s principle blogger on this topic fully capitulates — is not the only scientifically credible position out there. When you dig into the technical literature, many parts of the standard story turn out to be based upon very weak evidence. In short, there are strong scientific reasons to dispute the claim that humans evolved from ape-like precursors. Is it acceptable to point this out?

It seems to me that whoever makes a claim about how we got here has the burden of proof. Both sides are making claims, so both sides have to shoulder the burden of proof. Our side had made claims about what would be found in the human genome for years, and we were vindicated recently with research published in Nature. Can the other side do that?

I recommend reading the whole article. There are good links in there to other things that Luskin has written on this topic, and links to the research he uses in his arguments as well. There’s also a new book out now on human origins that presents more evidence on both sides of this debate.

Polemics

Greg Koukl debates Michael Shermer on God, atheism, meaning and morality

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The full transcript of a debate between Michael Shermer, editor of Skeptic magazine, and Greg Koukl, president of Stand to Reason. This debate occurred on Hugh Hewitt’s radio show, and was moderated by Hugh Hewitt.

HH = Hugh Hewitt
GK = Greg Koukl
MS = Michael Shermer

Here is a 32-page PDF with the full debate transcript.

And here’s an excerpt:

GK: Right. Actually, the big question here, Hugh, is whether it’s possible to be good without God. Now I’m not talking about whether it’s possible to be good without a belief in God. I certainly think that’s possible, but be good without God. And the answer to that question hinges entirely on precisely what you mean by good. And so I was going to give an illustration. So a man drags a young girl into the alley, he sexually abuses her, strangles here, and tosses her into the dustbin. Is that act wrong? Now I think everybody listening is going to admit it is wrong. But here is the real question. What do we mean when we say that that act of rape and abuse and murder is wrong? Are we describing the action itself, the object? Are we saying that the object, the rape, the murder, has a quality of being wrong, and therefore, wherever that rape goes, the wrongness follows it, just like your height, 6’ 2”, or whatever it is, is an objective quality of you. Wherever you go, your height follows you in the same way. Does the wrongness follow the rape? Well, if it’s a quality of the rape, if it’s an objective quality of the rape, then it does. And it doesn’t matter what people think about it, or what cultures decides, or what your evolutionary conditioning is. The rape is still wrong. The other alternative is that you’re not talking about the rape. You’re talking about yourself. You’re talking about your genetic conditioning. You’re talking about your culture’s decision about that kind of thing. And if that’s the case, then the truth of the wrongness of the rape is simply in the individual or the subject. And this is why philosophers distinguish between ethical objectivism and ethical subjectivism. Now there’s lots of different subjectivisms in ethics. But simply put, if you’re an ethical subjectivist, you’re a relativist. And actual ethics don’t exist. Ethics are an illusion. If you conclude that ethics are an illusion, there’s lots of different ways to explain it. Michael’s written a really great book, I think, called The Science Of Good And Evil. I’ve read most of it, and it’s well written, and it’s very compelling. But it’s a description about how the illusion of ethics has taken place. If you want to go that route, you’re welcome to go that route. But what you can’t do is you can’t then talk about morality as if it’s objective when your explanations are subjective. So this is a problem that I think all atheists, including Michael, have to solve. Are ethics objective or relative? And if they’re relative, then how can we make moral judgments that are meaningful on other people?

HH: Michael Shermer?

MS: Wow, let’s just get right into it. Well, I don’t think it’s quite so black and white. That is to say I think there are provisional moral truths that exist whether there’s a God or not. In other words, it’s wrong, morally, absolutely morally wrong to rape and murder. And that would be true whether there was a God or not. In other words, if…is God saying that it’s wrong because it’s really wrong, and He’s instructing us in his Holy Scripture that it’s wrong? Or is it only wrong because He said so? And if it turned out there wasn’t a God, would that make it okay? And my answer is no, it really is wrong, whether God says it’s wrong or not. That is to say I think it really exists, a real, moral standard like that. Why? Well, because first, you could ask the person who is being affected, we should always ask the moral recipient of the act, how do you feel about being raped or murdered or stolen from or lied to. And the moral actor will tell you, it doesn’t matter whether, if I could use a current example, I haven’t any idea if Tiger Woods and his wife are religious or not. But you can just ask his wife whether it was morally right or wrong, and she’ll tell you. It doesn’t matter whether there’s a God or not. It’s wrong. And so that’s the first principle. Just ask. Ask the moral recipient of whether it’s right or wrong. But I think Greg’s after something deeper, that is to say is there something even deeper still behind the moral actor’s feelings about how they’re treated. And the answer is yes, I think so. We’re a social species. We don’t live in isolation. We live as members of a group. And as such, there’s no possible way our group could survive, be cohesive, be a unit of any kind of solidarity against other groups, or against a harsh environment. If there were too much violations of social norms, that is if there were constant lying and cheating and raping and murdering, there’s no way a social group could hang together. And as such, as we all know, we’re very tribal. We’re tribal against other groups, but within our groups, we’re very pro-social, altruistic, cooperative. We have a good and evil in our nature. So to this extent, I find myself interesting often in agreement with my conservative friends on most of the things they consider morally, moral truths. That is, we share the same moral values, even though I come at it from a different perspective.

HH: Greg?

GK: Yeah, I’m actually not after something deeper here, Michael. At least to start out the discussion, I’m trying to be as simple and clear and precise as possible, because it’s very easy to weave together a bunch of things that sound persuasive, but turn out to be different things. Like for example, Darwinian evolution, which is a materialistic process, and here I mean the blind watchmaker thesis, the neo-Darwinian synthesis, natural selection working on mutations, and a kind of a cultural evolution that Michael has just referred to as we work together as a group to survive as a group. Those are two entirely different things. One is materialistic, Darwinian, the other one is intelligent design, quite frankly, where the group gets together and makes some determinations to encourage some behavior and discourage others. What I’m trying to do is to be able to answer the question that came up initially, is God necessary for morality, which Michael denies. It’s to say well, what is it that morality, that we’re trying to describe? It is either objective, and therefore an immaterial obligation that applies to certain behaviors, or it is subjective. The things that Michael described were variously subjective, evolutionary elements, subjective cultural elements, but then he affirmed that we all have good and evil in our nature, or an awareness of that. I agree with that entirely. We all are aware of those things. That’s why even if we don’t believe in God, we can still know morality and follow it. The question is what accounts for real, genuine objective morality?

HH: One minute to the break, Michael Shermer.

MS: I’m not arguing for cultural evolution. I’m actually arguing as part of our, what you described as materialistic, natural selection, Darwinian evolution, that it’s not enough to just pretend or fake being a good group member. You actually have to believe it, feel it, and live it. So what I’m arguing is that natural selected certain moral sentiments, as Adam Smith called them, moral feelings, an actual empathy, Adam Smith talked about, we actually empathize with somebody else, we can put ourselves into their shoes and feel their pain, I’m arguing that’s very real. It’s every bit as real a part of our evolutionary heritage as our eyes and our hands.

– – – –

HH: Michael Shermer, when we went to break, you were saying that evolutionary biology has produced a real morality.

MS: Yeah, I think really, Adam Smith had it right in his very first book, The Theory Of Moral Sentiments, long before Darwin, that we actually have in our biological nature, our human nature, the capacity to feel other people’s pain. He called it empathy, we think of it often either as empathy or sympathy. That is, we really do connect to other people. A lot of good research on this now, brain scans, you can show somebody a little video of somebody they know, or have feelings for, getting pricked with a pin, and the same areas of their brain light up, the pain receptors, as in the person getting the pin prick. In other words, we have an evolved tendency to really be deeply, emotionally connected to our fellow group members. And that’s why I say groups like World Vision, where you want to adopt a child, it doesn’t help to show a picture of 10,000 starving African kids. What does affect us is one child, a picture of one child with a little biography. That’s how you get people to adopt a child to donate. The reason for that is because essentially they’re tricking the brain, our brains into making that stranger an honorary family member, an honorary within group member, which is why I argue that free trade is one of the best ways of defusing normal tribal tensions between people. It makes them honorary friends, honorary members. Well, what’s going on there is we’re tricking the brain into sort of this evolutionary rule of thumb – be nice to people that are like you and that are related to you, and that you know, and that are fellow group members, and don’t do what our natural tendency is, is to be tribal and xenophobic against those other guys. And free trade is one of the best things you can do for that. So I’m arguing that’s actually tapping something deep within us.

HH: Greg Koukl?

GK: Yeah, basically, I agree with Mike completely here. We do have this tendency, and it seems to be universal among humankind. The question is, what is that tendency, actually? And what is the best way to explain it? And I see like a handful of significant problems with using evolution to explain morality. The first one is that evolution is a materialistic process. And here, I’m going back to an original point, and I don’t want people to lose it. There is no way that you can take molecules, and reorganize them in any fashion, over any length of time, and have pop out of the mixture an objective moral principle that’s immaterial, and that applies to human beings. All you’re going to get is a reorganization of the molecules. And what they can produce, and this is what Mike has done in his book, and he mentioned just s few moments ago, they can produce sentiments. They can produce feelings. They can produce behavior. But this leads us to the second problem of using evolution to explain morality, is that morality is more than sentiments, feelings and behavior. Morality entails things like motive and intention. I mean, you could have a guy walk into a garage, walk out with a hose, and is that wrong? Well, it depends. Is it his hose or somebody else’s hose? Did he intend to take the other person’s hose? Is he borrowing the hose? So we can see here are elements that are part of the moral thing that needs to be explained, that are immaterial, and therefore the Darwinian explanation can’t even in principle go there. It can’t do that job. But here’s the worst problem. Regardless of what our sentiments happen to be regarding moral actions, we can feel good or feel bad or whatever, the problem is that morality is prescriptive, not merely descriptive. That is it tells us not just what we did, but what we ought to have done in the past, and what we ought to do in the future. That is not something that any Darwinian mechanism can describe, because nothing about my biology can inveigh upon me to act a certain way for moral reasons in the future. It doesn’t tell me why I should be good tomorrow. This is a huge difference between these two views, the descriptive and the prescriptive. Prescriptive is part of morality, and can’t even, in principle, be explained by an evolutionary materialistic system.

HH: Michael Shermer, I’ll give you a start on that. We have about 45 seconds to the break, so you may want to…we’ll come back after the break and pick up. But what’s your start to that?

MS: Well, the start would be that again, let’s not think of evolution just as nature red and tooth and claw, and it’s nasty, brutish and short, but that in fact, we have this whole other social evolution. And I’m not talking about cultural evolution where we consciously make decisions, but subconsciously, because it’s in part of our nature to actually, seriously, deeply feel for other people and their actions, and the consequences of our actions, so that we actually have a sense of right and wrong that we’re born with, but then culture taps into and tweaks, one way or the other.

– – – –

HH: Michael Shermer, when we went to break, Greg had made the argument that the Darwinian model simply cannot explain immaterial concepts like morality, that there’s just no way you can rearrange the molecules to get there. You’re saying well, yes you can.

MS: Yeah, I think so, because if we think of morality as another suite of emotions that are involved with other people’s behaviors, the consequences of our actions, how we feel about them, how people feel about us when we do these things, that’s as every bit as important a biological part of our nature as anything else we talk about. So let’s take a real simple emotion. When you’re hungry, nobody does any calculations about the caloric input/output ratios of eating an apple versus an ice cream, although now it’s posted on the walls for us to see. But we just feel hungry, and we feel hungry for certain kinds of foods. The feeling of hunger is a proxy for something else. Evolution’s done the calculating for us. You need food, so we’re going to, your hypothalamus is going to secrete these certain chemicals that causes your stomach to rumble and so on. When you’re attracted to somebody else, a member of the opposite sex, nobody does the calculation by, let’s say, a man finds a woman attractive who has a .67 hip to waist ratio, and an hourglass figure, although that is pretty much universal. Nobody walks about with calipers taking measurements of who they’re going to want to date or ask out. You just look around, and you just go wow, I really find this woman attractive. It’s a feeling you have, okay? So those are kind of simple emotions, but sliding up the scale, the moral emotions are really no different. When I lie to somebody, I’ve violated a social norm, and they respond in a very angry, hostile way. So those emotions that we both share, guilt, shame, anger, disgust, involved a social relationship that whether it was a norm violation, those are the kinds of emotions that are just like hunger and sexual attraction that are built into us by nature, by evolution. Or, if you wish, this is how God created the moral sentiments, just like He created everything else in the universe, through a process of nature. I think that’s equally reasonable to argue. So I don’t see that it has to be an atheistic viewpoint versus a theistic viewpoint to get to our moral sentiments. Why couldn’t God have used evolution to create the moral sentiments as I’ve described them?

GK: Yeah, well, you don’t actually believe that, I know, Mike, so this is kind of like adding God to the soup, you know, if it makes people feel better. But the basic argument is that evolution all by itself can do the trick. And I think if your listeners are listening carefully, what they’re going to hear is Mike has just described, and if I’m being unfair to your assessment here, let me know, Mike, that moral feelings are simply that. They are sophisticated emotions that do some work for us for survival, and even on a group level. Now there’s a name for this. It’s called emotivism. A.J. Ayer, the famous atheist, offered this description of morality. It’s a relativistic scheme of morality. Morality doesn’t actually exist, Ayer argued. There is no objective right or wrong. Rape isn’t wrong itself. What happens is, we have feelings about it, and we express it in moral language, but rape isn’t really wrong. So your listeners are going to have to ask themselves the questions. When they just survey their own moral senses, and we all have access to this, do we want to believe that scientists have figured out that really what we’re doing is feeling sophisticated, complicated emotions, and that the emotions are in us, and we are not seeing anything about the action? Or does it seem like rape is wrong? Look, when I say rape is wrong, I’m talking about the rape. When I say liver is awful, I’m talking about me. I’m talking about my own tastes and preferences. It’s interesting, as Michael has given his explanation, though, that he’s doing, and I don’t know if you are aware of this, Michael, but you’re doing the very thing that I kind of warned against. You give a description of the foundations of morality that turn out to be relativistic, but then there’s a smuggling of a more objectivistic morality in the back door, like when Michael says you don’t have to do what your nature tells you to do, in other words, what you’ve been programmed by evolution to do. You can kind of rise above that. Well, now we’re talking about a morality that isn’t dictated by evolution, but a morality that we can employ through our acts of will, to rise above this kind of brutish evolutionary morality. And that sounds suspiciously like the very thing that I’m talking about here.

MS: But I don’t mean, there’s nothing to rise above by itself. Yes, we have to say rise above our tribal instincts to be xenophobic when we meet somebody who’s a stranger, who’s different from us. We all struggle against that, particularly in a black and white America, where there’s always been this underlying tension. Indeed, so culture helps us do that – education, travel, diversity of exposure to different people. That makes you a little more tolerant. Okay, but I’m not talking about that. What I’m talking about is tapping into the good part of our nature, the fact that in addition to that xenophobic tribalism we have, we also have this other side that almost never gets discussed in evolutionary…even in evolutionary circles, you’ll still hear evolutionary biologists talking about, in a way that Huxley did, and Herbert Spencer did in Darwin’s own time, that we have to somehow struggle mightily against our genes to overcome that nasty tendency we have to want to rape, kill, pillage and destroy. Well no, actually, we have this whole other side that’s just as genetically programmed into our nature. And the point of culture – education, politics, economics and so on, is to tap into the better angels of our nature as Lincoln said.

GK: Okay, here’s the question I have for you, Michael, then. You’ve identified that really, we have good and we have bad. That’s part of, under your terms, that’s part of our genetic nature, and we can choose to tap into what you call the good side. Why ever should we do such a thing if there is not a higher standard that directs our action to the better side, your words, than the bad side, your words, if really, ultimately, they are both the result of a genetic evolution, and from outside terms, neither is better than the other. Why should we do that, Michael?

MS: Yeah, well I don’t see how entering God into the equation changes that problem at all.

GK: Well, that’s the next step. What I’m trying to show is that the should comes from the outside, and if we can demonstrate that, then we can ask…

Read the rest by click here to get the PDF.