Questioning Evolution

[Jstwebbrowsing]

Okay, internet aside for the time, I have a few questions/objections about evolution myself.  Here is the first.

Is this assumption correct?  Organisms evolve to survive.

[One Above All]

No. It's a lot more complex than that. If you want to learn more, I recommend Google or Wikipedia.

[Jstwebbrowsing]

This is not really the right board for this, but the people I'm speaking to are not likely to see it in the correct board.

I admit I am mostly ignorant in science and I tried to put up a facade.  I apologize if I have offended anyone.  I hope we can get past it.

That being said, I would like to continue to participate in discussions.  I'm not likely to ever agree there is no god, but there is a lot I could learn here if I have not completely pissed everyone off.

[One Above All]

I think I'll let Omen point out the problem with your newest post.

[Quesi]

Great question.  I am not one of the science experts here, but I'll give a brief response. 

Genetic mutations happen all the time.  At some point, perhaps, I'll tell you my personal story with unexpected genetic mutations.  But let's just start with that.

The vast majority of mutations do not change anything substantial in a species.  But every once in a while, a mutation changes a specific characteristic.  Maybe it changes the color of an animal's fur, which results in the animal's ability to camouflage itself.  The animal that is able to camouflage itself is more likely to hide from predators, and therefore is more likely to live to reproduce, and more likely to pass on that color of fur.  That animal's offspring are more likely to have that color fur, and are more likely to survive, and more likely to pass the fur color on to their offspring.  Within a few generations, nearly all of the surviving animals will have the new fur color. 

So organisms do not evolve to survive.  Organisms undergo mutations, and some mutations change certain characteristics.  If a specific characteristic increases the survival rate of members of that species, chances are it will be passed on to future generations, and ultimately the species will change. 

Does that make sense as an introduction to the concept?  I am sure that there are lots of resources here that members can share with you. 

[Omen]

Okay, internet aside for the time, I have a few questions/objections about evolution myself.  Here is the first.

Is this assumption correct?  Organisms evolve to survive.

When we say evolution we are talking about methods by which life forms evolve.  There are many such mechanisms to explain various observed natural phenomenon, not all of them are necessarily the same, but they do share a commonality with darwinian natural selection.

The actual 'process' behind darwinian natural selection isn't that a life form evolves to survive, but instead evolves a characteristic that allows it to procreate more efficiently.  Survival isn't really all that important, because even if a life form survives for a long time if it never procreates it will never pass down whatever inherited traits that helped it survive.  This is a little over simplistic, because there are some other detailed ins and outs.

Earlier you talked about speciation as if it were separate from the rest of evolutionary science, this is false.  There are no separate mechanisms for speciation as opposed to a life form just evolving, there are types of speciation categories where a kind of selective criteria gives rise to a new species, however darwinian natural selection occurs all the time above and below the level of species.  Sometimes you hear this worded microevolution vs macroevolution, these labels are just classifications of quantification of change ( how much ).  Creationist often treat micro and macro as if they were somehow evolutionary mechanisms unto themselves, but they are not.

Something else to point out about darwinian natural selection is that it doesn't mean that a life form just instantly 'poof!' and gives birth to something else.  Evolutionary changes may not even be apparent and often rely upon smaller gradual changes.  Those kinds of gradual changes do not even need to occur in the same lineage of an individual family, for example  two different organisms of the same species might evolve different traits separate from themselves, later on the descendants of those two organisms may interbreed and exchange the traits that they evolved separately unto themselves.  This kind of intermixing occurs all the time and evolutionary changes can arise out of it.

Another problem with failing to understand evolution is what it means when a speciation event occurs.  Earlier I mentioned several types of speciation, where individual kinds of selection events give rise to enough changes for scientist to identify an organism as a new species.  Creationist often treat this as if the arrival of a new species means that the species it came from no longer exists, this is simply not true.   A single species might gradually evolve as individual members in the species more efficiently procreate and spread their genes throughout the population, they procreate better than other members of the same species and eventually their genes become dominate.  Enough changes might occur that would require the species ot be classified as a new species or a sub species, etc.  In another example a single species may become divided, where one species is geographically isolated from another.  Their geographical isolation would prevent the exchange of genes and each species may evolve separately from each other into different species.  ( these are simple descriptions; there are more varied and detail specific kinds of speciation events )

[Quesi]

Here is a fun game that someone posted on this board a while back.  It expands on the concepts that I just introduced.  It is quick and short and easy. 

May I recommend that you play it through a bunch of times.  The events that change the environment are random.  If you select a species with fur, and the weather randomly turns cold, your species will survive the cold.  But if you select a species with no fur, and it gets cold, your species might not survive.  On the other hand, if the game randomly sends you a hot spell, your hairless creatures will do better than the furry ones.

The same mutation might ensure survival in one environment, or have no effect on survival in another environment, and it might even add to the likelyhood of extinction in a different environment. 

http://science.discovery.com/interactives/literacy/darwin/darwin.html

[ParkingPlaces]

One of the things that you need to get out of your head about evolution is the assumption that there is a purpose. Everything evolves as a side-effect.  Something that has evolved successfully enough to survive any given environment may stay more or less the same for millions of years or, if the right combination of things occur, a new species may emerge. For a variety of reasons.

Genes change, causing physical or other biological changes. If those changes manifest themselves is positive ways in the critters they affect, then said animal may slowly change into some other species as it starts specializing in eating a new type of food or living in another environment. Longer fur might mean it can live further north or south. A more effective respiration system might allow it to live in hotter, dryer climates. The legs may have gotten longer due to genetic change and suddenly the critter can run faster and cover more ground.

Humans may well have succeeded when they climbed out of the trees because the leg and lung changes that occurred made us great runners. A good human runner now cannot outrun a deer, but it can outlast a deer, and chase it down in a couple of hours by wearing it out. Then you just walk up to the thing and hit it over the head with a rock.

Most changes, however, are detrimental and kill off the recipient of the gene change. Or offer no major advantage. The critter may still be on the way to being a new species if only because the feather colors change or it starts eating by climbing up trees instead of walking down them.

Don't forget that all this takes place over an incredibly and unhuman amount of time. We can't think in terms of millions of years. Our imagination can't handle such numbers well. Let along billions of years. But you have to factor time in with the other forces of change.

We have no trouble finding genes in humans that not only match genes in yeast, but that perform the same function in both. We can match genes in other critters as well. And plants. And sponges and sea urchins. So some of our genetic material is still similar to other species. While other material has changes drastically. Thats why putting people in bread dough is of little use.

If we didn't have evidence for this stuff, it would be way to incredible to even consider. But we don't even need the fossil record to provide sufficient evidence to show that evolution has and does occur.

You mentioned in the other thread that you sort of understood viruses or bacteria (I forget which you were talking about) evolving, but that they were still viruses after they were done. It works in big things too. We evolved from older species of apes. And we're still apes. So not all big changes cause a fish to become a salamander. Though that did happen. Other fish became us. We know that because the nerve in fish that used to go from the brain to the gills, and past the fish heart on the way, now controls swallowing in humans and other mammals. And it still goes past the heart on the way. Except the heart is not in a direct line any more, so it has to leave our brain, go down around our heart, and return to our throat. In giraffes, instead of going about a foot, it goes 14 feet. Evolution doesn't have to be efficient, it only has to work.

Not that efficiency isn't better. It's just that there is no actual planning involved, so silliness like that is commonplace.

Sometimes it has repercussions. Like the human back, which was worked fine in our ape ancestors as we ran around in trees. When we stood upright, our back went along for the ride but didn't like it. Thats why at leat 25% of us suffer from serious back problems in our life. Because our back is a weak link in our skeleton. An error typical of evolution. And one I would hope a god making us would have avoided.

Evolution via the genetic change process helps some critters survive. Others die because of it. There are no guarantees. Stuff happens. Sometimes good, sometimes bad.

Life is a crapshoot. So far we humans are winning. If you don't count the backstabbing that we've evolved to do so well.

[Tero]

Organisms strive to live and reproduce. They carry genes. Genes have some variety, naturally.

Evolution has no particular goal or direction.

Galapagos finches settle into certain sizes and bill lenths. The entire population of related species can produce this collection, even if destroyed all the mid size ones. None of them are "best" compared to the others.

I suggest you read a book. The example was from Beak of the Finch.

[Jstwebbrowsing]

Thank you.  Those were very good answers.

So basically evolution is random.  Some changes help keep you alive but most will get you killed?

My second question actually was if the original species became extinct.  Thant was already answered.  So that changes a few things.  I guess there wouldn't be much variety otherwise.

Okay then the next question.

What's the most change that can occur, or has occured, in a single generation?  And if it's a lot then does this occur frequently?  And I am talking about in some sort of animal.  I'm better off staying away from microscopic things.

[ParkingPlaces]

Well, this is a hard one to answer. At least without doing some research.

There are groups of people in different parts of the world, including Portugal, that have six functioning fingers. Sometimes on one hand, sometimes on both.

I'm pretty sure they didn't start out by having 5.1 fingers. So that would be a pretty good example. It may lead to all humans having six fingers in a few hundred thousand years. Or it may die out. Or it may stay localized. Six fingers do not a new species make, nor does any other one generation change. But it could be the start of something big.

So invest in glove stock. 

Edit - Added this:

I started investigating the how big question and learned that there is a term for really big changes. It is called "saltation". The only problem is that no change big enough to qualify as saltation has ever been found. But some theorize that it could happen. Right now it is not considered a part of evolutionary theory. I assume mostly because it has never been observed. Which seems like a good enough reason to me.

[Alzael]

What's the most change that can occur, or has occured, in a single generation?  And if it's a lot then does this occur frequently?  And I am talking about in some sort of animal.  I'm better off staying away from microscopic things.

It's a hard question because it's difficult to measure change in a species.At least small changes. It's also hard to measure things in form of a "magnitude" as biology doesn't function on set scales. Even the difference between various species can be open for debate often. The question of at which point does a poodle change enough to become a whole new breed of dog is the sort of thing biologists argue about a lot.

Actually (as an aside) it reminds me of a story told once in a lecture by Kenneth Miller (one of the leading biologists, and a practicing Christian BTW) in which he speaks of one of his colleagues who was sitting down at a meeting where she and some of paleontologists were trying to classify some fossils of a new species that had been found. He reports that once they started almost immediately virtual fistfights broke out among the scientists whether the species should be classified as  "mammal-like reptiles" or "reptile-like mammals".

Back onto the topic at hand.

There is a school of thought regarding what is called Punctuated Equilibrium (put forth by Stephen Jay Gould) as a theory in evolutionary biology. The idea is that it is possible that a species can exhibit little change over a large period of time. Then suddenly experience a great surge of change in a relatively short period. This is a fairly debated theory however that has a lot of criticism from some prominent biologists (like Dawkins) but the theory does have some evidence behind it so it hasn't been thrown out. Unfortunately it's often misused by creationists who twist the words of the theory into an argument against evolution. Much to Goulds annoyance.

Note that this is not a theory that I personally subscribe to. But it is one possible theory.

[ParkingPlaces]

Note that Alzael's mention of Punctuated Equilibrium needs to be understood as big changes that take place quickly, but only quickly in the time scale of evolution. Rather than taking hundreds of thousands or millions of years to have a large scale change occur, said change happens in a shorter than usual span of time.  25,000 or 50,000 years or something. By human standards, it is still incredibly slow.

And as I understand it, the theory of Punctuated Equilibrium states that most speciation happens this way.

And as a further aside, computers programmed to simulate evolution have periods of Punctuated Equilibrium occur in the simulation. That doesn't prove anything, but it does show that the parameters as they are currently understood do allow for such rapid changes.

And also note that not all biologists/paleontologists accept that Punctuated Equilibrium is real. In fact, a lot of them don't. There are areas of controversy within the discipline. But only in the specifics, not in the general idea of evolution itself.

[mrbiscoop]

Thank you.  Those were very good answers.

So basically evolution is random.  Some changes help keep you alive but most will get you killed?

My second question actually was if the original species became extinct.  Thant was already answered.  So that changes a few things.  I guess there wouldn't be much variety otherwise.

Okay then the next question.

What's the most change that can occur, or has occured, in a single generation?  And if it's a lot then does this occur frequently?  And I am talking about in some sort of animal.  I'm better off staying away from microscopic things.

  The genetic mutations that power evolution are indeed random. However evolution (natural selection) is not.
   You are probably going to continue having problems with evolution until you accept that evolution happens over vast periods of time.

[JeffPT]

So basically evolution is random. 

No.  The MUTATIONS are random.  They are errors in the copying process.  An insertion here, deletion there, a substitution over yonder;  that sort of thing.  Remember that DNA is coding for something. Whether it be protein synthesis (around 5%) or something more like gene regulation (much greater %)

A simple analogy is to think of DNA and it's A-C-G-T stuff like a line of text. You start out with a sentence...

I will not work today. 

Then you add a letter in someplace (say... the letter 'r' between the 'o' and the 't' of 'not) and see what happens, making sure to keep the same structure of 1 letter, 4 letters, 3 letters, 4 letters 5 letters.  This is what you get.

I will nor twor ktoda. 

This is catastrophic failure and may result in big ass problems for the organism depending on where it happens.  Now lets try taking a letter out and see what happens.  Let's take the 'r' out of the word 'work'.

I will not wokt oday. 

Less damage, but still not so great.  May be good or bad for the organism.  Now lets replace a letter and see what happens.  Let's replace the 't' from 'not' with a 'w' and see what happens. 

I will now work today.   

It still makes sense but it is a wholesale change in the meaning of the sentence, or in the case of DNA, a significant change in the presentation of the individual.

So when you think about it, a simple change in the DNA pattern or sequence will give rise to a slightly different individual.  The manifestation that occurs as a result of this DNA change can either give the individual an increased chance to survive in whatever environment they are in, or a decreased chance. If it gives them an increased chance to survive over others of the same species, then over long stretches of time, that new DNA strand will be more likely passed on from generation to generation, simply because the individuals with that DNA sequence are better suited to survive where they live. 

Some changes help keep you alive but most will get you killed?

Actually, from what I understand, most don't do much.  But the ones that are beneficial are rare, yes. 

What's the most change that can occur, or has occured, in a single generation?  And if it's a lot then does this occur frequently? 

This is a really interesting question because you have to think of it in a few different ways.  My guess is that any large mutations would almost always have catastrophic implications for any offspring, because an individual would not always be able to deal with the changes (I.E. if you were to have a genetic mutation causing you to grow a third arm, you need to have blood supply to it, nerve innervation, bone structures, etc).  That would explain why we don't see superhero's running around with bullet proof skin and such.  But if you want to look at survivable changes that occur within a single generation, just look up genetic disorders. Things like Cystic Fibrosis, Down Syndrome, Cri-du-chat syndrome, etc. 

Here is a giant list of genetic disorders from wiki...

http://en.wikipedia.org/wiki/List_of_genetic_disorders

[DumpsterFire]

Okay, internet aside for the time, I have a few questions/objections about evolution myself.  Here is the first.

Is this assumption correct?  Organisms evolve to survive.

The concise answer is that organisms do not evolve to survive, but they do experience random mutations. The few whose mutations are favorable are (slightly) more likely to survive and, therefore, to pass their favorable genes onto further generations. Over vast amounts of time these small changes add up to huge differences.

[ParkingPlaces]

And keep in mind that random mutations in such a complex process are more likely than exact copies happening every time.

And its more fun this way.

[joebbowers]

What's the most change that can occur, or has occured, in a single generation?  And if it's a lot then does this occur frequently?  And I am talking about in some sort of animal.  I'm better off staying away from microscopic things.

Well, in Sri Lanka a chicken just gave live birth. As in, it incubated the egg internally like mammals and birthed a fully-formed chick. That's a pretty significant change to occur in a single generation. The mother hen died giving birth but the chick survived. It's possible that the chick carries that mutation as well, and will itself also give live birth, and so on, thus creating an entirely new species of chicken. Time will tell if this turns out to be an advantageous mutation. I would think so, as it would mean the chicks are protected from egg-snatching predators or bad weather while incubating.

[jaimehlers]

Another thing to keep in mind is that a successful species tends to evolve less.  This isn't because the rate of mutations differ, but because the successful species doesn't need to change its behavior in any appreciable manner.  So even if it gets a beneficial mutation, it may not ever be expressed in a meaningful fashion.  Compare that to a species on the edge of survival, which has to work much harder to survive.  Evolutionary changes like color (making it less likely to be caught and killed) or what it can eat (allowing it to eat more varieties of food) make a much bigger difference in that case.  And if you get enough evolutionary changes stack up, you end up with an organism which is substantially different than others of its species (which is were you get "races" and "breeds").  And if they get separated somehow, they may diverge in how they reproduce, meaning that you won't have viable offspring that can themselves reproduce ("mules" - a mixed breed which is itself sterile, such as the actual mule, or a liger/tiglon).

[Grogs]

What's the most change that can occur, or has occured, in a single generation?  And if it's a lot then does this occur frequently?  And I am talking about in some sort of animal.  I'm better off staying away from microscopic things.

Well, keep in mind that mutations affect individuals so that question is a bit ill-formed. The population as a whole won't be significantly affected for several generations, potentially hundreds or thousands if the population is large, before the mutation spreads significantly and begins to change the entire species. So, I think a better way of asking would be "What is the largest variation that can be introduced into a population by mutations in a single individual?"

That question is fairly easy to answer in the abstract. In order to pass on its genetic information, an individual must be able to survive to breeding age, reproduce with a member of its own species, and produce a viable offspring. There's no guarantee that the mutation will breed true though, so even then the mutation may be lost. Also, capable of reproducing viable offspring is somewhat ambiguous. For example, chihuahuas can technically breed with great danes, but due to mechanical difficulties such a mating would be extremely unlikely to ever happen.

[bertatberts]

Okay, internet aside for the time, I have a few questions/objections about evolution myself.  Here is the first.

Is this assumption correct?  Organisms evolve to survive.

Organisms evolve for many reasons.
However one creature that has been noticed over the last two hundred years is the peppered moth, which did what your question asked and evolved for survival sake. I.E. to continue the species http://en.wikipedia.org/wiki/Peppered_moth_evolution

[Add Homonym]

Thank you.  Those were very good answers.

So basically evolution is random.  Some changes help keep you alive but most will get you killed?

There is an element of redundancy, because we carry a gene from both parents. If one gene which creates a protein/enzyme gets corrupted, then we still have a working copy of the original, and the new mutation can be an experiment. The experiment may not do anything, or it may be a slight change in morphology of an enzyme., which allows an enzyme to attack a different toxin, or do something novel with a chemical floating around in your blood. The redundancy allows for a non-committal experiment. Without this redundancy, any change to a protein would probably be fatal.

Due to genetic drift, a lot of these subtle protein changes, with no rhyme or reason, can build up in individuals, with no bad effects. Then, you get a stressor of some kind, and if the individual happens to have mutations that allow tolerance of the new stress/disease, then it obviously is a score! Evolution works ahead of time, not because the organism wanted to achieve something (Lamarkian).

There is not a hellava lot of difference between a rat and a human. This is why scientists insist on using them as human models in labs. If you stretched a rat body this way and that, you could make it look like a human. Once you had made a rat look like a human, one of the main apparent differences would be intelligence and spinal strength. Once you fixed that up, you would have to remove the instinct to pee smelly stuff all over the place.

When Creationists focus on 'mutation', they typically imagine mutations to be catastrophic changes, like extra limbs and heads. However, you will notice that all mammals have 5 toes and fingers, 1 liver, 2 kidneys, 2 lungs, 2 eyes; so these types of morphological mutations are uncommon, except on phylum boundaries; like arachnids vs insects. Nearly all of the changes are trivial tamperings that have redundancy.

The bulk of tricky evolution, such as eyeballs, has to be done in particularly fast-reproducing, small ocean animals. There is not really any way for a human-like organism to evolve anything terribly adventurous, because our reproduction and population is too slow and small, and our environment is too variable and challenging. The ocean is a sort of amorphous soup, with approximately 1.3 bazillionty animals in it. For example, one species of krill has a population of about 10 million billion. Krill has way over 10 million times to capacity to evolve as the current human population.

[relativetruth]

Okay, internet aside for the time, I have a few questions/objections about evolution myself.  Here is the first.

Is this assumption correct?  Organisms evolve to survive.

No!

Organisms  survive because they evolve.

[relativetruth]

^^^^^
IE They evolve/change (mutations) first and then find themselves adapted to their environment.

They do not change themselves physically because they notice things are changing about them.

[Jstwebbrowsing]

First I want to really thank you all for taking the time to answer my questions.  You have been surprisingly very thorough too.  I've never actually had the opportunity to talk with people this well versed in science.

On to the next:

I was watching a show last night about cosmology that reminded me of this question.  The scientist showed that everything around us is made of star dust because we're made of the atoms that came from them.  The Bible states that Adam was formed from the dust of the ground.  If we assumed that he created other animals in similar fashion what would geneticists expect to be different in their code than if they evolved?  I don't argue with science that genetically humans are little different from other animals.  But wouldn't this be true no matter which way they came to be?

[One Above All]

Your question is nonsensical. Abiogenesis and mythology do not mix. If we assume one to be correct, then we must assume the opposite for the other.

[JeffPT]

I was watching a show last night about cosmology that reminded me of this question.  The scientist showed that everything around us is made of star dust because we're made of the atoms that came from them.  The Bible states that Adam was formed from the dust of the ground.  If we assumed that he created other animals in similar fashion what would geneticists expect to be different in their code than if they evolved?  I don't argue with science that genetically humans are little different from other animals.  But wouldn't this be true no matter which way they came to be?

Not to nitpick, but humans are 70% water, and at birth around 80%.  If anything, we are formed from the sea.  It's a small point, but I thought I would add that in.  Evolution holds that our ancient ancestors are from the sea.  The God theory does not.  BTW, star dust is not like the dust on the ground.  Star dust is every element including the ones that make up water and all other liquids known to man.  I would think the term 'star matter' would be a more accurate description, but star dust just sounds really cool. 

Also, we are talking about the theory of evolution here.  What you have to ask is whether or not the genetic codes that are similar between animals, plants, bugs, bacteria, humans and every other living thing, are consistent with the theory that we evolved from earlier living things.  If it's yes, then an unproven god theory (whether it be your god or another god) is unnecessary.   


 

[ParkingPlaces]

We wouldn't be so obviously related. The apes, of which humans are a part, are all very close genetically. The cats, which we are not a part of, are all very close genetically. The same goes for all the other animal and plant groups. Yet we also all share gene sets. Geneticists can trace many human genes back to the bacterial level and find the same ones there. Or in yeasts or ferns or mushrooms. Common gene groups have been passed down from the very beginning and all animals have some that are identical to what exists in the oldest life forms. And yet each animal also has its own gene pool that defines it as a bat or an earthworm or a shark.

A god creating a bunch of custom life forms would not seem restrained by genetic material. He could make whatever he wanted. We are genetically close enough to mice that we can test medicines on them first before starting human trials. Is that because a god planned ahead for our convenience, or because evolution happened to work out that way? The genome of the flatworm Caenorhabditis elegans has been studied exhaustively, and once its genome was mapped, scientists figured out that they could study human diseases ranging from Alzeimers and retinitis pigmentosa  to cancer and diabetes by studying the worm more closely. Because of genetic similarities between a tiny flatworm and us huge humans. And this works because we are related, not because some god or other whipped us all up out of dust and used a few similar components for the sake of convenience.

And while we are discussing evolution here and not the formation or existence of the universe, the connection is such that we can't totally ignore one while studying the other. Since you mentioned stardust keep in mind that the star formation/life cycle that they go through was required for the creation of the heavy metals and other elements. We humans require iron, and that came from stars. Same with oxygen. Otherwise we wouldn't have water. And star formation and destruction was required for almost all of the other elements that you see listed on the periodic table. So it wasn't just dust in stardust. It was us. And almost everything else.

But that is an aside in this discussion on evolution. Just thought I'd toss it in for a little clarification.

[Quesi]

Were you watching something with Neil DeGrasse Tyson?  He often gets all poetic and starts with his "we are stardust" monologue.  Here is a beautiful piece in which he finally gets to the "we are stardust" stuff. 



I am quite moved by him and his work. 

This is a little off topic, but I couldn't resist sharing.