Evolution theory and teratology

What I mean by teratology very broadly is any discourse about freak babies or anomalous features in babies or birth deformities.An example of teratological phenomenon is a lady I know who is absolutely normal and even pretty, but in her small finger of the left hand there is a very small protruding finger like a twig from a branch of a tree.Are teratological features of offsprings the changes that are taken to be mutations, which will be naturally selected according to the circumstances of environment, so that after millions of years a different species will appear?I can speculate that the lady with that extra very small finger in the left hand small finger and all others like her, men and women, after millions of years will become a different species of homo sapiens or sub-species.What is the use of such a small extra finger?Why, in my part of the world we eat a small snail that is at most 3/4 inch in diameter and we have to use a thorn from the rose tree to pick out the organism inside to get to it and eat it.So such people with an extra small finger need no longer use a thorn from the rose tree, they can use their extra small finger and thus have one advantage over people without the extra small finger.If and When the only food available to mankind are those small snails, then they will definitely survive in the long run after millions of years while the rest of mankind without the extra small finger will become extinct.Anyway, tell me, knowledgeable people here, are teratological features facts of evolution as intended by the theorists of the evolution theory?Yrreg

Yes, those would be examples of mutations. Mutations come in three flavors: good, bad and neutral...and those terms are dependent on the environment the organism lives in. The same mutation could be advantageous in a wet environment but disadvantageous in a dry one.Whether a mutation is passed on depends on if that organism has a chance to breed. The mutations that are most likely to spark a new species are ones that offer up a significant reproductive advantage. A mutation that helps an organism survive longer than those without it, for instance, means that organism has more mating periods in which to pass its genes on.As for your lady friend, I assume she has every opportunity to reproduce. So now the question is whether the mutation that allowed her to grow another finger is a mutation that exists in her gametes. Human evolution is a tricky discussion because we are a lot less subject to our environment than we used to be. Rather than adapt to our environment, we adapt the environment to us. Groups of people will very rarely enter into reproductive isolation for the long amount of time it would require for a new species to arise.

This is a good question, although coffee house is not the right place for it, it's clearly a legitimate 'Biological Evolution' topic.The chances are that such a supernumerary finger could be the result of an environmental effect during development rather than the sort of heritable genetic mutation involved in evolution. I could be wrong, but you would need some familial history to find out.Having said that there are plenty of genetic mutations which are known to produce polydactyly in humans.In a situation such as you described with the snails then a genetic mutation leading to an additional small finger might well come to prevail, provided that there really was any sort of fitness advantage which I don't think your hypothetical example really shows.Even were the extra finger to become predominant I see no reason why it would lead to speciation in terms of two co-existing reproductively isolated populations, unless the people decided for themselves to practice segregation on the basis of finger number. Whatever the human race is like in a million years, in the unlikely event we make it that far, it would very likely constitute a distinct species to modern man, simply because of the genetic change which is bound to accrue over such a long period. Such a hypothesis cannot be supported however due to the impossibility of testing interfertility between populations separated by such large spans of time. In general no, in specific instances yes. But not 'facts of evolution' like an organism magically growing a new organ from nowhere but as in a fact regarding the role that genetic mutation has in producing phenotypic variation and a fact relevant to the role of the genes affected by the mutation on normal development and possible repercussions on our view of how that gene may have changed during evolution.TTFN,WK

Thread moved here from the Coffee House forum.

Mutation and millions of years determine good, bad, or neutral mutation.Mutation can be good, bad, or neutral.We will know that after millions of years and we are still around and the mutation proves to be good.Good meaning I am sure, the members of the mutated species have survived to the present.Bad is when the mutation did not enable the changed species to survive millions of years.And neutral if the mutated feature is still around but we can't figure out why it is still around, how it serves in enabling the mutated species to survive to the present.That is really scientific thinking in terms of what, like for example the theory of relativity?Yrreg,

Hi Yrreg, No. Mutation is just mutation. Natural Selection determines whether it is good or bad. This happens on a very much shorter scale than "millions of years". Yes. No. A "good" mutation (a more accurate term might be "beneficial") is one that helps the individual organisms that carry it to survive and successfully reproduce. Note that I'm talking about the day-to-day, year-on-year process of survival and reproduction here; ordinary organisms surviving, finding mates and making babies. If the mutation helps its carrier survive long enough to produce viable offspring, then the mutation is considered to be beneficial.As an example, imagine a bird that carries a mutation that gives it sharper eyesight. That bird would be better able to find food, to avoid predators, to find a mate or find a good nesting site. These advantages, though slight, would add up to an increase in the bird's chances of surviving and successfully reproducing. Thus the gene is more likely to get passed on and is considered beneficial.Millions of years are not required, unless you want to talk about many generations. No. Bad (a better term might be "harmful") mutations are those that hinder an organism's efforts to survive and to reproduce. If a mutation makes it harder for the organism carrying the mutation to survive long enough to successfully reproduce, that mutation is considered harmful. Remember, we're talking about a mutation that would have originated in a single individual here. If it makes that individual (or any offspring that carry the same gene) less likely to survive and successfully reproduce, it is harmful.As an example, imagine a bird that carries a mutation that gives it blurry eyesight. That bird would be less able to find food, less able to avoid predators, less able to find a mate or find a good nesting site. These disadvantages, though slight, would add up to a decrease in the bird's chances of surviving and successfully reproducing. Thus the gene is less likely to get passed on and is considered harmful.Again, millions of years need not come into it, unless you want to talk about many generations. No. A neutral mutation is one that neither helps nor hinders the organism.If we weren't able to figure out what a given mutation does, then we would not be able to say for certain whether it was beneficial, harmful or neutral. Most mutations however, are neutral.If a mutation actually did serve in "enabling the mutated species to survive to the present", it would be beneficial, not neutral. Mmm. If I were you Yrreg, I'd stick to one theory at a time.Mutate and Survive

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"A curious aspect of the theory of evolution is that everybody thinks he understands it." - Jacques Monod

Naa. This is the twisted dishonest thinking of yahoo creationists who, if they had bothered to do the most minimal level of research before opening their mouths to insert their boots, they would have known that mutations are classified beneficial, harmful or neutral based on their effect to the present individual not millions of years from now.They would have known that beneficial mutations give a survival advantage, and more importantly a reproductive advantage, to the individual and that over the generations this beneficial trait will become more and more prevalent as a percentage of the population.But, it seems, such creationists, like yourself, are too intellectually dishonest to find out what the concepts really mean before they throw out insults.Edited by AZPaul3, : change title

Actually, there is a difference between teratogens and mutagens. Teratogens cause a dysfunction in embryonic development that is unrelated to DNA sequence. One of the more famous examples is thalidomide. This sedative caused dysfunction in embryonic development that resulted in stunted limb development. Thalidomide did not cause a specific mutation that caused short limbs. It interfered with cell to cell signaling during embryonic development.So no, teratological features are not automatically considered to be mutations of DNA sequence.

Thank you, Taq. And am I glad I read to the end of the topic before responding to Perdition's 2008 post: In addition to that, there's also the question of what kind of mutation we're talking about. A mutation could either be caused by a change in the genetic code or by conditions that had affected the embryo's development. I think that most of the mutations that creationists talk about, the really obvious ones, are developmental mutations, whereas the only mutations that could ever possibly be of any evolutionary interest are genetic ones, and for that matter only genetic changes in the germ cells (AKA sperm and ova).Let's face it, if the mutation cannot be inherited, then what good is it? If the mutation is purely the result of environmental conditions during development and did not change the genetic code that would show up in the subject's gametes (AKA sperm or ova, depending in the subject's gender), then such mutations are meaningless, evolutionarily speaking.John Maynard Smith pointed that out. He then described the four types of mutations what would be of any evolutionary importance, all of which related directly to the DNA sequences (from memory, base substitution, base insertion or deletion, sequence duplication, sequence reversal). But the bottom line was that if that mutation is not inheritable, then it is meaningless in evolutionary terms.Taq, you have pointed out that teratological features are not inheritable. Therefore, yrreg's OP and this entire topic is moot and void of any possible relevance to evolution.In conclusion, I would like to tip my hat to two forum members. These two have chosen names that truly reflect themselves. Bolder-dash posts nothing but balderdash ("stupid or illogical talk; senseless rubbish"). Yrreg is bass-ackwards and everything he posts is also bass-ackwards. Despite the frustration of having to deal with their idiocies, you've got to admire their truth in advertising -- they have already informed us of exactly what they're going to give us.

Or they're example of failures in the developmental process which are not genetic in origin.

Of course you have got stock answers to all the questions people outside your box address to you.Stock answers from the stocks of your authority doctrinaire mentors.Plus the stock strawmen.Just one more question:What is the natural factor in natural selection?Is it the blind and purposeless nature that should not care anything about survival of whatever, as to lead to stability of surviving species, in the time span they do survive in?Yrreg

Almost.The environment is what it is. As you say, it really doesn't care about anything.Those species that survive, survive. Nothing related to care or purpose.If the conditions change, the surviving critters may well become the losers.That's how it works.

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Anyone so limited that they can only spell a word one way is severely handicapped!

Nature.You know, that green business outside your door where all the plants and animals live?

You mean two questions. You just can't get anything right can you. Nature. Yes.I take it back. You were right about that last one. Congratulations.

Hi Yrreg, Oh Christ. Please don't start that box stuff again. If you wish to engage in any meaningful way with the Theory of Evolution, whether you intend to challenge it, support it, or simply understand it, you need to know what the theory actually says.Your little potted version of mutation and natural selection was wrong in almost every detail. I gave you the accepted version, the kind of summary of the very basics that you would get in any Biology 101 classroom. Until you grasp those basics, you are wasting your time pontificating on a theory you do not understand.You might, at some point, like to find out what the Theory of Evolution actually says. Then, when you understand at least the basics, you might be able to make meaningful statements about it. You don't have to believe it, but at least then you'll know what it is that you disagree with.It's called "learning". Go on, give it a whirl. It might help you avoid those strawmen you're so critical of.Mutate and Survive

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"A curious aspect of the theory of evolution is that everybody thinks he understands it." - Jacques Monod