Tag Archives: Selection

Three logical prerequisites for biological evolution to work

Hummingbird in flight
Hummingbird in flight

Biologist, blogger and super-mom Lindsay has written a post that explains what supporters of Darwinian mechanisms have to prove in order to explain the origin and diversity of life.

Here are the three things that Darwinists must demonstrate:

  1. It is possible to add biological information.
  2. There are more upward steps than downward steps (or at least a way to get more upward steps than downward steps at least some of the time).
  3. There does exist a gradual genetic pathway that can be climbed in tiny, incremental steps.

So first of all, the main two arguments for intelligent design and against naturalism are the origin of life and the Cambrian explosion. Both involve massive infusions of new biological information. So Lindsay is right to focus on whether Darwinism can add new biological information. But I wanted to focus on number three, because I really think that her post is about the burden of proof on Darwinists more than it is about our burden of proof. And we do need to get used to asking Darwinists for the evidence for their view.

Take a look at the detail on number three:

In order for evolution to be true, not only does information have to be added over time, but each successive change must occur in a living organism and it must be conserved by being passed on to offspring. Thus, the change cannot kill the organism or seriously disable it, or the change will not be passed on. This must be the case for EVERY step in the entire evolutionary sequence, no matter how small. At every step you must have a functional organism. Thus, the changes must be gradual enough that the tiny upward steps (if they exist) can achieve each new level without killing or disabling the organism. To use a simplistic analogy, if one tries to change from one word to another by changing one letter at a time (cat to cot to dot to dog, for example), there must, at every step, be an actual word that can be reached by changing one letter. In the Mount Improbable analogy, this means that there can be no upward jumps in the trail. If the maximum possible upward step is 6 inches, then there can be no 6 foot cliffs along the trail, or even 7 inch steps. If ever there is a step which requires more information than unguided evolution can provide, then evolution is falsified in that instance. It cannot account for the change in information if that is the case.

Now I have never seen a gradual genetic pathway from one body plan (phyla) to another body plan (phyla) in any peer-reviewed paper. What I need to see to believe in the ability of Darwinian mechanisms to drive change from one body plan to another is that sequence of changes at the genetic level. And I don’t just need to see the steps, I need to see the probabilities of getting the correct sequence of changes at the genetic level within the time available by chance. That’s what Darwinists assert in their theory – that’s what they need to prove. Talking about how one creature looks like another creature is irrelevant. My car looks like my Dads car, because we drive the same model, but different model years – and both cars are designed.

When people ask our side for evidence for our claims, we are able to produce the evidence to substantiate our claims, e.g. – cosmic fine-tuning factors or protein sequencing probabilities. I would like to see the other side do the same, and not just tell me a story. When I question people in the arts who accept Darwinism, they seem to be terribly disinterested in the details, and just want to jump to the conclusion shared by the smart people without thinking hard about all the steps in between. That’s intellectually lazy. The same thing happens with global warming with the non-scientists – they are more concerned about jumping to the “smart people” position, so you think that they’re smart. They aren’t really interested in hearing both sides, or looking at the evidence. I think people need to take it slow and look at the evidence, instead of deciding what to believe based on how other people perceive them. No need to rush to agreement to build up your self-esteem without doing the hard work first.

If you are looking to understand what the other side has to prove, and in a concise way, read her post.

New study: natural selection can act to impede speciation

Australian Walking Stick
Australian Walking Stick

My friend KL sent me this press release from the University of Colorado at Boulder.

It says:

An intriguing study involving walking stick insects led by the University of Sheffield in England and the University of Colorado Boulder shows how natural selection, the engine of evolution, can also impede the formation of new species.

The team studied a plant-eating stick insect species from California called Timema cristinae known for its cryptic camouflage that allows it to hide from hungry birds, said CU-Boulder Assistant Professor Samuel Flaxman. T. cristinae comes in several different types — one is green and blends in with the broad green leaves of a particular shrub species, while a second green variant sports a white, vertical stripe that helps disguise it on a different species of shrub with narrow, needle-like leaves.

While Darwinian natural selection has begun pushing the two green forms of walking sticks down separate paths that could lead to the formation of two new species, the team found that a third melanistic, or brown variation of T. cristinae appears to be thwarting the process, said Flaxman. The brown version is known to successfully camouflage itself among the stems of both shrub species inhabited by its green brethren, he said.

Using field investigations, laboratory genetics, modern genome sequencing and computer simulations, the team concluded the brown version of T. cristinae is shuttling enough genes between the green stick insects living on different shrubs to prevent strong divergent adaptation and speciation. The brown variant of the walking stick species also is favored by natural selection because it has a slight advantage in mate selection and a stronger resistance to fungal infections than its green counterparts.

“This is one of the best demonstrations we know of regarding the counteractive effects of natural selection on speciation,” said Flaxman of CU-Boulder’s Department of Ecology and Evolutionary Biology, second author on the new study. “We show how the brown population essentially carries genes back and forth between the green populations, acting as a genetic bridge that causes a slowdown in divergence.”

A paper on the subject appeared in a recent issue of the journal Current Biology. 

[…]“This movement of genes between environments slows down the genetic divergence of these stick insect populations, impeding the formation of new species,” said Aaron Comeault, a former CU-Boulder graduate student and lead study author who conducted the research while at the University of Sheffield.

So, in the past I had read that natural selection can act as a stabilizing force in nature – keeping the organism operating within a type. This study seems to be confirmation of that. But there are other problems with generating macro-evolutionary change.

Also related to the problem raised by the study is this problem of genetic drift, which also works against the preservation of beneficial mutations.

Evolution News explains the genetic drift problem:

Evolutionary biologists often assume that once mutations produce a functionally advantageous trait, it will easily spread (become “fixed”) throughout a population by natural selection. For example, imagine a population of brown-haired foxes that lives in a snowy region. One fox is born with a mutation that turns its fur coat white, rather than brown. This fox now has an advantage in hunting prey and escaping predators, because its white fur provides it with camouflage. The white fox survives, passing its genes on to its offspring, which are also adept at surviving and reproducing. Over time, the white-haired trait spreads throughout the population.

This is how it’s supposed to work — in theory. In the real world, however, merely generating a functionally advantageous trait does not guarantee it will persist, or become fixed. For example, what if by chance the white fox trips, breaks a leg, and gets eaten by a predator — never passing on its genes? Random forces or events can prevent a trait from spreading through a population, even if it provides an advantage. These random forces are lumped together under the name “genetic drift.” When biologists run the mathematics of natural selection, they find that unless a trait gives an extremely strong selective advantage, genetic drift will tend to overwhelm the force of selection and prevent adaptations from gaining a foothold in a population.

This underappreciated problem has been recognized by some evolutionary scientists who are skeptical of the ability of natural selection to drive the evolutionary process. One of those scientists is Michael Lynch, an evolutionary biologist at Indiana University, who writes that “random genetic drift can impose a strong barrier to the advancement of molecular refinements by adaptive processes.”2 He notes that the effect of drift is “encouraging the fixation of mildly deleterious mutations and discouraging the promotion of beneficial mutations.”3

I guess the point of this is that if someone wants to convince you that macro-evolution is possible through the mechanisms of random mutation and natural selection, then they have some work to do. And it’s more work than just asserting that it happened.

People who are technical may benefit from reading Michael Behe’s book “The Edge of Evolution”, which studies how likely it is to get several positive adaptations in a row within a reasonable period of time.

UPDATE: A biologist friend tells me that “whether natural selection is driving speciation or preventing it, in neither case is it explaining how these organisms came to be in the first place. It only explains how existing organisms interact with their environment. And this can be explained at least as well through intelligent design as through naturalistic processes.” She also says that natural selection can drive speciation, but still within a kind.

Should we be mentoring women about how to make important life decisions?

In response to Lindsay’s post about why women are so interested in “50 Shades of Grey”, I thought I would post some other really strange stories how some women make decisions.

But first this recent study reported in Newsweek. (H/T Levene)

Excerpt:

Scientifically, nice (heterosexual) guys might actually finish last. A study published in Personality and Social Psychology Bulletin recently found that while men were attracted to nice-seeming women upon meeting them, women did not feel the same way about men.

[…]While the studies shed some light on why men find responsive women more sexually desirable, Birnbaum explains that researchers are still unsure why women are less sexually attracted to responsive strangers than men.

“Women may perceive a responsive stranger as less desirable for different reasons,” said Birnbaum in a press release. “Women may perceive this person as inappropriately nice and manipulative (i.e., trying to obtain sexual favors) or eager to please, perhaps even as desperate, and therefore less sexually appealing. Alternatively, women may perceive a responsive man as vulnerable and less dominant.”

That comports with a previous story I wrote about showing that women decide whether they like a man or not based primarily on first impressions.

From the UK Daily Mail.

Excerpt:

It takes a woman just three minutes to make up her mind about whether she likes a man or not, a study has revealed.

The average female spends the time sizing up looks, physique and dress-sense as well as taking in scent, accent and eloquence of a potential suitor.

Women also quickly judge how he interacts with her friends and whether he is successful or ambitious.

It also emerged most women believe 180 seconds is long enough to gauge whether or not he is Mr Right, or Mr Wrong.

The study also found women rarely change their mind about a man after their initial reaction – and believe they are ‘always right’ in their assumptions and judgments.

The report which was commissioned among 3,000 adults to mark the release of Instinct, a new book by Ben Kay.

Kay said: ‘I think a lot of people believe in trusting their instincts when dating. It makes it seem more magical, like it’s coming from somewhere deeper.

That last sentence is key, I think, in understanding the problem. Some women feel no need to look at academic transcripts, resumes or balance sheets in order to evaluate a man – they think that they  can decide if a man is successful or ambitious based entirely on appearances. I think the culture is leading them to do that, too, because it never used to be like this before.

Now two older stories showing how wrong this can really go.

The first one is from 2010. It’s about a string of conversions to Islam by women in the UK.

Here’s an example story:

Women like Kristiane Backer, 43, a London-based former MTV presenter who had led the kind of liberal Western-style life that I yearned for as a teenager, yet who turned her back on it and embraced Islam instead. Her reason? The ‘anything goes’ permissive society that I coveted had proved to be a superficial void.

The turning point for Kristiane came when she met and briefly dated the former Pakistani cricketer and Muslim Imran Khan in 1992 during the height of her career. He took her to Pakistan where she says she was immediately touched by spirituality and the warmth of the people.

Kristiane says: ‘Though our relationship didn’t last, I began to study the Muslim faith and eventually converted. Because of the nature of my job, I’d been out interviewing rock stars, travelling all over the world and following every trend, yet I’d felt empty inside. Now, at last, I had contentment because Islam had given me a purpose in life.’

‘In the West, we are stressed for super­ficial reasons, like what clothes to wear. In Islam, everyone looks to a higher goal. Everything is done to please God. It was a completely different value system.

‘Despite my lifestyle, I felt empty inside and realised how liberating it was to be a Muslim. To follow only one god makes life purer. You are not chasing every fad.

‘I grew up in Germany in a not very religious Protestant family. I drank and I partied, but I realised that we need to behave well now so we have a good after-life. We are responsible for our own actions.’

For a significant amount of women, their first contact with Islam comes from ­dating a Muslim boyfriend. Lynne Ali, 31, from Dagenham in Essex, freely admits to having been ‘a typical white hard-partying teenager’.

She says: ‘I would go out and get drunk with friends, wear tight and revealing clothing and date boys.

‘I also worked part-time as a DJ, so I was really into the club scene. I used to pray a bit as a Christian, but I used God as a sort of doctor, to fix things in my life. If anyone asked, I would’ve said that, generally, I was happy living life in the fast lane.’

But when she met her boyfriend, Zahid, at university, something dramatic happened.

She says: ‘His sister started talking to me about Islam, and it was as if ­everything in my life fitted into place. I think, underneath it all, I must have been searching for something, and I wasn’t feeling fulfilled by my hard-drinking party lifestyle.’

So this is not a cognitive conversion, it’s about personal fulfillment.

And then a while back there was the legions of teen fangirls in love with this convicted terrorist Dzhokhar Tsarnaev.

The UK Daily Mail reported on it.

Excerpt:

A startling number of teen girls have admitted to having a schoolgirl crush on bombing suspect Dzhokhar Tsarnaev, proclaiming their love for the Boston Marathon bombing suspect on social media.

Its a disturbing trend on sites like Twitter and Facebook, where girls have admitted to finding Tsarnaev attractive, and herald him in the ranks of Justin Bieber and One Direction singer Harry Styles.

One Twitter user, a waitress who goes by the name Keepitblunted, has said she is looking to get a tattoo of a Tsarnaev quote. ‘If you have the knowledge and the inspiration all that’s left is to take action.’

[…]Another says she is considering becoming a Muslim to better related to Tsarnaev.

The FreeJahar97 Twitter account was created on April 25 – 10 days after the double bombing.

The first tweet reads: any other beliebers out there who want to see Jahar freed and believe he is innocent? feel like i’m all alone here.. #freejahar.’

I know I didn’t know Jahar and I shouldn’t be saying this but… I miss Jahar… Is that weird? Don’t think I’m weird. I just miss him.

Tsarnaev5ever tweeted: ‘Jahar is gonna go crazy in that cell alone with just a book… I wanna send money to him… Anyone have the address?’

‘Poor Jahar… He’s only 19. ONLY 19… No one deserves to be in a 10×10… No one…’

Shadowlilly1993 posted: ‘Yall can judge me as much as you want. I’m on his side.This kid needs people behind him. I hope to meet him one day he fascinates me @J_tsar.’

I guess my response to all this is that we ought to be talking to young women about how they are making big life decisions. Shouldn’t we be doing a better job of helping women to think through what their life goals ought to be rationally and then helping them to make practical plans to achieve them? It just seems to me that there is something inside them that attaches great confidence to their emotions. Without anyone sensible to talk to about how to reach a goal through a chain of sensible steps, they can really mess up their lives. And then very often, government grows to help them pick up the pieces – we all have to pay when that happens, you know.

It’s probably a good idea for women to be more careful about picking men – after all, the man you choose will father your daughters. He’d better be good at leading women before he gets thrust into that role.

Three logical prerequisites for biological evolution to work

Biologist, blogger and super-mom Lindsay has written a post that explains what supporters of Darwinian mechanisms have to prove in order to explain the origin and diversity of life.

Here are the three things that Darwinists must demonstrate:

  1. It is possible to add biological information.
  2. There are more upward steps than downward steps (or at least a way to get more upward steps than downward steps at least some of the time).
  3. There does exist a gradual genetic pathway that can be climbed in tiny, incremental steps.

So first of all, the main two arguments for intelligent design and against naturalism are the origin of life and the Cambrian explosion. Both involve massive infusions of new biological information. So Lindsay is right to focus on whether Darwinism can add new biological information. But I wanted to focus on number three, because I really think that her post is about the burden of proof on Darwinists more than it is about our burden of proof. And we do need to get used to asking Darwinists for the evidence for their view.

Take a look at the detail on number three:

In order for evolution to be true, not only does information have to be added over time, but each successive change must occur in a living organism and it must be conserved by being passed on to offspring. Thus, the change cannot kill the organism or seriously disable it, or the change will not be passed on. This must be the case for EVERY step in the entire evolutionary sequence, no matter how small. At every step you must have a functional organism. Thus, the changes must be gradual enough that the tiny upward steps (if they exist) can achieve each new level without killing or disabling the organism. To use a simplistic analogy, if one tries to change from one word to another by changing one letter at a time (cat to cot to dot to dog, for example), there must, at every step, be an actual word that can be reached by changing one letter. In the Mount Improbable analogy, this means that there can be no upward jumps in the trail. If the maximum possible upward step is 6 inches, then there can be no 6 foot cliffs along the trail, or even 7 inch steps. If ever there is a step which requires more information than unguided evolution can provide, then evolution is falsified in that instance. It cannot account for the change in information if that is the case.

Now I have never seen a gradual genetic pathway from one body plan to another in any peer-reviewed paper. I am talking about from one phyla to another. What I need to see to believe in the ability of Darwinian mechanisms to drive change from one body plan to another is that sequence of changes at the genetic level. And I don’t just need to see the steps, I need to see the probabilities of getting the correct sequence of changes at the genetic level within the time available by chance. That’s what Darwinists assert in their theory – that’s what they need to prove. Talking about how one creature looks like another creature is irrelevant. My car looks like my Dads car, because we drive the same model, but different model years – and both cars are designed.

When people ask our side for evidence for our claims, we are able to produce the evidence to substantiate our claims, e.g. – cosmic fine-tuning factors or protein sequencing probabilities. I would like to see the other side do the same, and not just tell me a story.

If you are looking to understand what the other side has to prove, and in a concise way, read her post.

Is there a smooth pathway from micro-evolution to macro-evolution?

From Luke Nix who blogs at Faithful Thinkers.

Excerpt:

Macroevolutionary changes are a lot of microevolutionary changes, but they are in a specific series that follow a specific pathway. The missing premise in this argument is that the pathway from ancestor to claimed offspring (many generations down the road) is clear of obstacles.

In his book, “The Edge of Evolution” Michael Behe shows that scientists have observed such an obstacle in the lab. The obstacle was not time, it is in the genetic pathway that must be traversed if macroevolutionary changes are to take place in reality. Since an obstacle has been observed, we now have a false premise in the argument. Since there is a false premise, the argument fails. There is a difference between micro- and macro-evolutionary changes. A lot of microevolutionary changes are necessary for macroevolution, but they are not sufficient. The other sufficient condition (a clear genetic pathway) still has yet to be met. Since both sufficient conditions for macroevolution have not been met, it has not been demonstrated. And since changes over time has been demonstrated, there is a need to distinguish between the two. To prevent confusion about what we know to be true and what we don’t, this distinction must be made.

There is only one way that this can be overcome by the naturalist: find a pathway that would be clear by default in nature. Notice that I have added one more piece to the missing premise above: “…clear by default in nature“. I have to add that last qualification because as scientists are looking for a way to overcome this obstacle, they are introducing their own intelligence- fine-tuning the process, then “allowing nature to take its course”. Their conclusion of naturalistic macroevolution will depend on a premise that is founded on intelligence. That would undermine the whole argument for naturalistic (macro)evolution.

This is one of the ways to show that evolution is true – by showing a pathway to macro-evolutionary change in the lab. If people expect me to believe in the grandiose claims of fully naturalistic evolution through a stepwise process, then why can’t I see the pathway myself? If you make the claim that it happened, then I want to see the evidence for the claim.

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