Transterrestrial Musings

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We are not all that far from being able to 'see' speciation happening.
You might be interested in this post I made recently ... http://jottings.blogspot.com/2002_06_02_jottings_archive.html#85137361

Posted by John Weidner at June 4, 2002 02:20 PM

I know that, but the rejoinder is "but they're still finches." As though they're expected to have become anteaters.

Posted by Rand Simberg at June 4, 2002 02:38 PM

But finches that'll strip a man to the bones in under a minute! You have to give them credit for that.

Posted by Eric Pobirs at June 4, 2002 05:24 PM

And Rand, that rejoiner is profound. Consider that mutation is the driving engine of evolution, and of course mutations do occur (regardless of the fact that they breed out too) the point it...

The observed variation in finches requires no call to evolution. None. Assume no mutations, could the observations have occured? Yes. So occam would tell you to dispose of the theory (at least as an explanation of this particular observation.)

Darwin wasn't aware of this (although more consideration of Mendel might have given him pause.)

When David says, "Simple statistics shows use that it is highly probable these genes come from a common ancestor rather than independently evolving." The statement itself presupposes evolution.

Although I admit, I'm not prepared to refute David's argument right at this moment. I would like to meditate on it first. Frankly, being numerically illiterate - as someone so kindly pointed out - I work for a living but not as a mathmatician - has it's disadvantages.

Sometimes of course the answers are easier than they look. Like the other day when my son asked me to find the fifth root of an expression for his algebra class and I noticed that taking advantage of some identities made the solution a whole lot simpler.

Occam would have appreciated that.

Posted by ken anthony at June 4, 2002 06:07 PM

It's nowhere as profound as you think. In fact, in my opinion, it is not profound at all.

A different species is a different species. That it's still a member of the same genus just means that the process hasn't been given much time. Given long enough, it will migrate right up the classifications, to the point that it won't even necessarily be recognizable as a bird.

That people don't understand this is more a reflection on their mental inability or unwillingness to deal with the amount of time required for radical changes to take place, than any valid critique of the theory.

Posted by Rand Simberg at June 4, 2002 06:36 PM

As you've said before, "everything is a transitional species." However, what if that is not the case? My point is that if you take away mutations (the engine of evolution) you can still explain the data. Ergo occam.

Posted by ken anthony at June 4, 2002 07:16 PM

How do you explain speciation of finches without mutations?

Posted by Rand Simberg at June 4, 2002 07:38 PM

Put up or, y'know, creationista. If these changes in allele frequencies (i.e. evolution) don't matter then what explains the observed changes in finch populations?

Posted by Andy at June 4, 2002 08:07 PM

In this case we have solid evidence. According to the article you directed me to, during times of famine big beaked birds could crack seeds others couldn't while small beaked birds could find less accessable seeds. Medium sized beak birds died out. When the food supply returned so did the medium beaked birds because the trait still existed in the gene pool. Again, husbandry without evolution answers that question fine.

Here's a possible falsification of evolution that I'm not able to answer, but perhaps you or one of your readers can...

What is the statistical answer to this question (likely, possible or not possible)...

1) We are appoximately 97% genetically the same as modern ape (or more to the point for this analysis - 3% different.)

2) Our common ancestor with today's ape is suppose to have been 6 million years ago. So that if we could identify each link in the chain we would be 12 million years (and whatever number of generations) apart.

3) From observed data, what rate of mutation (observable defects) is passed on with each generation? Supply a reasonable number.

4) Do the numbers derived from 1 and 2 = 3?

I realize that asexual reproduction would much simplify this analysis (sex does tend to make a mess of things sometimes, eh? - Is it best when messy? Never mind!)

My simple math says 3%(~10 billion (those GACT groups))/ 12 million = aprox. 25 average changes per year. Wrong of course, but anyone out there (not grinding an axe like me?) willing to offer the correct answer?

And what number do we assign to impossible?

Posted by ken anthony at June 4, 2002 08:14 PM

Actually, you need to get your numbers right to start. We're about 98% with chimps. We're farther from other apes. And (if I recall correctly, the chimps are as far from the other apes as we are).

This in itself should tell you something.

I don't know the answer to the rest of your questions, but I'm sure someone does (though they may not be readers of this blog), and I don't have time to go dig them up.

Posted by Rand Simberg at June 4, 2002 08:39 PM

Ken, you're grossly overstating the role of mutation. This isn't the Marvel Universe.

Environmental events can readily act upon natural variations within a species to favor one of the variation scale over another. The classic grade school introduction to the survival of the fittest concept is fur density. A herd of whosits may have a fair variation in this while meeting the criteria for being a single species. An especially intense winter can wipe out the members of the herd in which thicker fur was not a dominant trait. The thick furred variant then becomes the standard. (Keep in mind this is a crude example. It's rather more complex in practice.) If after many filtering events like this the right portion of genome have been reinforced over others you can end up with a whosit that cannot produce fertile offspring with one of its ancestors prior to that devastating winter and following trials.

Mutations along the way may introduce new traits, even favorable ones for the time in question. It will also kill off a lot of otherwise viable creatures. It ups the ante in the Big Spin but it isn't the only game in town. Look at the domestic canines. Mutation contributed a good deal to the incredible variety of breeds but it's highly unlikely any of them them would exist today if Man didn't leverage artificial selection to emphasize traits he thought were nifty. (Some of those those guys were deeply disturbed.)

My sister has a Rhodesian Ridgeback. (Despite it sounding like an English name this is actually an obscure African tongue's phrase for 'giant shorthair squirrel.') The most distinguishing features this breed is the ridge of fur growing backwards along the spine. Unless this is inextricably linked to the genes for something very important to their survival it's difficult to imagine this trait becoming a dominant feature on its own. (Maybe the first was sent up on a test run in a rocket poorly shielded against cosmic rays before Reed, Ben, Sue, and Johnny made the trip.)

Posted by Eric Pobirs at June 5, 2002 12:05 AM

For another example of variation contributing to speciation just look at your own family. If you have a fair number of siblings you can probably think of a trait they were born with would have probably been fatal in pre-technogical times.

I was born with no wisdom teeth and never endured the pain of impaction and extraction as my four siblings did. OTOH, my appendix went bad when I just six. All of my sibling still have theirs. It wasn't all that long ago that either condition was potentially fatal.

My father died of a form of cardiovascular degeneration caused by a faulty autoimmune response to the common cold. The gene was identified just two years ago and it shouldn't be long before I can have my genome scanned to see if I carry the gene and if it's dominant. The condition is fatal within 3-5 years and can happen at any age. The odds, of course, increase with repeated cold infections and so it's more likely to hit older than younger people but it could easily act as a gating factor in which only certain members of a family managed to produce children. In the process other related genes could be winnowed out.

One trait I get from my father is a great resistance to cold. I got to hear a lot of German's questioning my sanity while trudging through a snow covered parking lot at Hannover Messe during CeBIT. Although I'm a native of Southern California I could apparently get along fine in some of the more frigid parts of the civilized world. But if I'm forced to get by in a place at the opposite end of the spectrum I might very well expire at an age unfavorable to producing issue. Many other humans are just the opposite. We're still the same species but take away our clever technology and a few generations of extreme weather might create a genomic gap that could no longer be crossed.

Artificial selection has had significant effect on one group of humans during the 20th Century. Tay-Sachs Disease (http://www.tay-sachs.org/whatista.htm) is an utterly horrific genetic disease that causes immense suffering and death by age five. I have nothing but contempt for anyone who would bring to term an embryo shown to have this condition.

This was one of the very first genetic diseases for which carriers could be easily identified with a blood test. Ashkenazim Jews (in which I fall) were among the hardest hit with doomed babies. But for a variety of reasons they also developed a high community awareness of the problem. My mother knew of several couples who chose to not marry after discovering both were carriers and would have a 50% chance of producing a Tay-Sachs afflicted child.

This awareness has been so high that recent report indicate that Ashkenazim now have the lowest incidence of Tay-Sachs babies, even lower than the general population. Some researchers claim that the number of carriers among Ashkenazim is also on the decrease but it's too early to produce dependable numbers. This suggests a fair number of carriers have chosen to be childless rather than let another generation suffer the risk. Some eager geneticist are examing the genomes of Tay-Sachs carriers to see if they have other genes in common rare or not found in the genaral populace and whether those gene do anything interesting. Might we be sacrificing something to eradicate a source of horrible suffering?

Posted by Eric Pobirs at June 5, 2002 12:51 AM

Question: are replication errors in germ line cells considered a form of mutation or categorized separately? A fair amount of this happens with no outside influence. Age along increases the probability in most species.

The probablity is for such errors to be detrimental but it can be the other way around. If enough of the same error is manifested in a breeding generation to keep it in the mix this can be a big step toward speciation.

Posted by Eric Pobirs at June 5, 2002 12:57 AM

Rand, ok. Instead of 3% of 10 billion assume 1% of 1 billion. My question was has anyone done the math.

Eric, my point exactly. Evolution is the marvel universe but many people aren't laughing.

The thrust of my comment was has anyone done the math (someone qualified, unlike me?) and does it support evolution or not?

Questions are the innocents of science (but I see you could still end up on the stake for asking the wrongs ones in the wrong crowd! Present company excepted of course! ;) )

As for replication errors I would say, why not? But treat it as a separate question. Likewise, sexual vs. asexual. If someone is willing to take on the more difficult question first, again why not. I just thought it would be instructive to try the simplest case possible for a starting proposition because it would help lead to the more difficult questions.

Posted by ken anthony at June 5, 2002 08:32 AM

The answer is, yes, someone has done the math. Google is your friend.

And no, evolution is *not* the Marvel universe. In the Marvel universe, people are bitten by nuclear spiders and become spiderlike overnight, or are exposed to radiation and periodically become unjolly green giants.

In the non-Marvel universe, it takes thousands of generations for significant change to occur, and animals never become invisible, or infinitely elastic (though they do occasionally become green).

Posted by Rand Simberg at June 5, 2002 09:17 AM

I've taken your suggestion and here is the surprising (to me anyway) result...

http://www.evolutionfairytale.com/articles_debates/mutation_rate.htm

http://abcnews.go.com/sections/science/DailyNews/mutation990127.html

There were a lot of google hits... I'll try to find both pro and con articles, but these are interesting.

Posted by ken anthony at June 5, 2002 09:34 AM

Uh, Ken, you do realize that the second article refutes the first?

Fed William's piece makes a complete hash of the researchers work by assuming any mutation classified as harmful is synonymous with fatal. It doesn't work that way. Just about any animal under close examination can be show to be a far less than perfect sample of its species. Survival doesn't say perfect gets to pass GO and collect 200 offspring while all others are bankrupt and out of the game. Otherwise you'd have to go way beyond intelligent design and suggest constant intelligent intervention to keep any species from dying out within a few generations of its creation. The Creationist have utterly painted themselves into a corner on this one.

Just to up the ante Williams drags out another old trick, giving the researchers full credit for accuracy but only where it suits the purpose of the argument's slant:

The high mutation rate from the Eyre-Walker & Keightley study was determined under the assumption of common ancestry between chimps and man. Since the rate is clearly too high, there are only two realistic explanations:

1) there is a mistake in their data or analysis (doubtful), or
2) the base assumption that man and chimp share a common ancestor is flawed (most likely).

"Hey, these guys are brilliant, at least on the part I can distort to my ends.

Additionally, as the ABC article mentions, human mutation levels are a very poor basis for judging evolution of life as a whole. For millenia civilization has increasingly improved the ability of individuals with serious defects to survive and reproduce. This has gotten to the point that we've recently had events like the lesbian deaf couple who purposely created two deaf children. Just to up the ante we often expose ourselves to nasty substance that can only exist through human artifice.

What I refer to as 'genetic vanity' has become so enshrined that people who have no business having children are not only encouraged but treated as heroes. Southern Californians may remember what happened to the radio talk show host who dared to suggest Bree Walker might be well advised to adopt rather insisting of producing her own kids with 50% probability of manifesting a severe diabling deformity of the hands and feet. You might say she beat the odds. She has two children, both of whom received her condition.

You can see things more horrible still in the work of the most decadent practitioners of eugenics: animal fanciers. Many dog breeds have defect rates so high you'd want to follow them around with a geiger counter to see if the source is having at your own gonads. If you released a large number of them into the wild with no other canines to interbred with there would likely be no trace but bones after a few generations. Meanwhile, canines who live under the rigors of natural conditions continue to do quite well.

While it does nothing to disprove evolution our mutation rates may be cause for alarm and certainly there are people trackin this with great interest. Our growing ability to intervene in our own genetics may become critical in preventing a disastrous drop off in viable births. This has been the grist for more than one novel. All too often the people who most vehemently oppose research into artifacting living beings are the same ones who are extremely uncomfortable with the suggestion that Man is not somebody else's artifact.

Posted by Eric Pobirs at June 5, 2002 10:44 AM

No, Eric, the conclusions are different but the evidence is the same (and like I said, surprising to me.)

Similar to previous post...
http://www.cs.unc.edu/~plaisted/ce/problem.html
http://www.cs.unc.edu/~plaisted/ce/uniformity.html

That poor fly...
http://www.fixedearth.com/THIRTY-SIX%20BRISTLES.htm

Concerning Genetic Algorithms...
http://www.trueorigin.org/geneticalgorithms1.asp

Ok, so I'm biased... sue me.

Posted by ken anthony at June 5, 2002 11:10 AM

The problem is that one set of conclusions is reached through a filter of axe grinding.

Ken, it doesn't matter how many people produce articles based on defective reasoning. No amount of repition of an incorrect statement will make it true. Note however, the comments before the bibliography of the Fixed Earth piece establish that the guy is either an utter loon or a masterful joker. Considering that his book does exist (yes, I've seen it) and he considers a 30+ year old attempt to refute genetics still valid my guess is weighted toward utter loon. The fly article was refuted at the time of its publication but lets ignore those unpleasant facts.

The piece on genetic algorithms is massively full of obfuscation, outright lie, and ignoring unpleasant truths. such things go hand in hand with axe grinding epithets like 'atheist' and 'antitheist' which the author uses at every opportunity as if it were incriminating in of itself.

Among its offenses the piece chooses to ignore nearly any work done after a certain date, thus confining the criticism to simulations that were limited by the available systems of the era. Moore's Law has allowed the complexity to grow by leaps and bounds. THe result keep coming up in favor of Darwin.

The place where the articles lapses from being merely wrong to laughable is the comment on generational time. How is this at all meaningful. The rules being tested say nothing whatsoever about generational time. It only factors in as a major part of what makes the simulation attractive. You have a chance to see something happen without waiting your whole lifetime for one run. The simulation runs on its own clock that serves for all elements within such as chemical reactions and entropy. In more recent sims the most complex animals had longer generational cycles due to the greater amount of information they contained compared to still extant simpler species from the earlier period of the sim. This is based on cycles of the simulation's clock and correlates very well to real word reproductive processes.

A look around the site containing the piece reveals another obsessive creationist. Your going to have to do better if you wish to be taken seriously. Science produces plenty of interesting internal conflicts to be resolved without any need to reserve seats for the delegation from the Tin Foil Headwear Society.

Posted by Eric Pobirs at June 5, 2002 12:23 PM

This just in -- Science is hard!

www.theonion.com/onion3821/science_hard.html

Posted by Eric Pobirs at June 5, 2002 12:34 PM

I agree there are lots of axes being ground, but here's the thing... Science has our confidence because of it's predictive ability. Regardless of what conclusion are drawn from the article by the author you must agree that his analysis is predictive. So what does the evidence show?

The research exists. They artificially increased the mutation rate in flies. Does this support his predictions or those of evolution. You have the links above. You can pick at the fine points but what in general does it show? Evolutionist argue that it could of happened this way or that(especially if coerced) but what does the simple evidence show?

Posted by ken anthony at June 5, 2002 12:40 PM

Science also has our confidence because it operates in the open and doesn't have an 'or else' clause if you argue a point.

Ken, I'm not going to be your personal research librarian. If you want useful information stop look to Creationist for honesty. They have noe. Their need to preserve Truth as Delivered Unto Us by God completely overwhelms their capacity for simple small 't' truth. Really, do you think biologist have formed a massive conspiracy to keep this suppres for several decades or is just an issue that was resolved log ago and only has historical interest today.

These people have been wrong over and over again but will keep trotting out same failed arguments because they know what P.T. Barnum knew. I recommend the work of Martin Gardner, as well as other prominent contributor to Prometheus Press and Skeptical Enquirer. He blew away the league of idiots and con men consistently decades ago and nearly all of his work holds up well today. The bozos he opposed have only grown more ridiculous as further data works against them. Occasionally a new guy jumps in to give the rhetoric an update but they unfailingly make the same classic mistakes.

Posted by Eric Pobirs at June 5, 2002 01:23 PM

I have to admit the quality of some of the articles I've read are pretty poor. Even my own comments suffer from the haste (I don't have time either) in which I compose them. However, I tend to look for the nuggets buried in the dirt. I think I have some legitimate questions although I may not pose them as well as I'd like.

I contend that defects breed out and the facts seem to support me. I'm not looking for creationist articles (although I admit in defense of my particular bias I will tend to point to articles that support some of my contentions.) I keep hearing people argue variations of the pepper moth scenario, when that is well known to *not be* an example of evolution.

I don't remember if I ever mentioned that my temperment is 'INTJ' on the Briggs-Meyers scale. Some references refer to that as the 'scientist' type while others more correctly refer to it as the 'pig-headed mule!' Which is to say all the evolutionist in the world, or all the creationists in the world, would be unable to change my opinion by there weight of numbers or how strongly they feel about their positions. What influences me are facts. Too often, those facts are ignored (by both camps) or glossed over. Yes, I am particularly aware, not saying I catch them all, when either camp makes an unsubstantiate (or even ridiculous) claim.

I'm not a specialist in these areas, nor do I offer myself as one (or play one on the internet as Rand says - I got a chuckle out of that.) To say we can't know something because we can't be around enough to see it is not a valid argument to me. If we can learn heredity from peas (and what is learned applies to us as well) we can certainly reason on this theory. Variation on the theme of animal husbandry do nothing to support evolution.

Although I knew they occured frequently, I was surprised to learn that mutations occur more often than I suspected. That is a new fact to add to my arsenal of knowledge. What conclusions I draw from that will have to fit into the other facts at my disposal. The age of a fact does nothing to diminish it, in my opinion, unless it is proven to be false of course.

The conundrum presented is a difficult one (particularly because I am ill equipped to do the mathmatical analysis required... I must depend on others) but it seems that these articles are saying that... and you seem to be agreeing with the proposition that...

Fast mutation rates lead to less viability and eventually die out, whereas slower rates are mathmatically unable to produce the observed outcome in the time alloted.

Plus that little nugget that never seems to go away... with sexual reproduction defects breed out.

Then what about this other issue of uniformity? Based on the low diversity of humans and the high mutation rate they could not have lived (or very recently had a severely depressed population - on the order of 8 people in a boat I suspect!) within the last 10,000 years? I say 10k so you can blame an ice age... ;-)

I'm not asking you to be my research librarian (I presume you have a life too ;-) Frankly, I don't regard evolution as having a bearing on my core beliefs, but I've heard stupid arguments on both sides of the fence and not many satifactory answers. Also, when I see people trying to bully others with their arguments (and you must admit that happens... again on both sides of the fence) I don't have much respect for that either.

Facts are irritating, but truth is worth the effort.

Posted by ken anthony at June 5, 2002 07:52 PM

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