Creationism vs. Evolution

[morriswalters 16]

I do not go to church, I've never found the way.  Neither do I worship at the feet of Darwin.  To often in these debates people lose sight of the word theory in the Theory of Evolution.  I does nothing more then present an idea which seems to explain the facts as they are  found.  While people treat it as dogma, it is subject to the same process as any other idea and will be modified as more information becomes available.  It cannot explain the why in any philosophical sense, only the how.  Like any good theory is should predict in some sense the behavior it's models.  It should be subject to testing, and it should be modified or abandoned if need be.  It may not be something that is ultimately provable because the beginning processes can't be replicated or reproduced.  It does seem to describe with some accuracy what is observed in nature.

Creationism or Intelligent Design are not per se testable scientifically since they depend on superior beings not subject to any test we can use.  This doesn't mean that they are not true but in a classical sense are not subject to the Scientific Method.  Depending on the particular theological point of view you inhabit there is nothing which would preclude evolution as the method used by the Creator to create the Earth.  The exception to that is inerrancy.  If you believe in the literal truth of the Bible then we must part company.

For those who wish a scientific debate, give me scientific data to test.  If it is a philosophical debate you want I can stand on either side of the subject and make points.  I respect the views that each of you hold as long as you respect mine.  As for what is taught in school, if a private school wishes to teach Creationism, have at it.  However in public schools my tolerance ends.  I have no desire for the Government in any fashion or form to become part of the discussion.  I don't care if your Christian, Jewish, Muslim, or whatever.  If you don't want your kids exposed for some reason then opt out and put them in Private schools.  I assume that those who believe in inerrancy would do that in any case.  I'm not sure that the subject needs to be taught in Elementary School at all.  At the very least Evolution as a Theory is very complex.  It's easily misunderstood and misinterpreted.  These things should be taught when a child has reached a point where he can reason critically and where his parents have had a chance to give the child the foundation to help them put it in perspective.

[A Nonny Moose 8,261]

Inerrancy In*er"ran*cy ([i^]n*[e^]r"ran*s[y^]), n.

Exemption from error.

[1913 Webster]

The absolute inerrancy of the Bible. --The Century.

[1913 Webster]

-- From The Collaborative International Dictionary of English v.0.48

A new word to me, but then I have only had seven decades to learn English.

[DazzaDazza 29]

Umm what an interesting topic…….

I am going to hold back some what I think. I guess if you look at the fact as they stand it pretty hard to argue with evolution. I went to a catholic school, and I had to go to church as a boy, but thankfully my parents only sent me to that school because it was a good school. But nether the less we had to learn about the bible. It mostly full of storeys rather good ones sometimes. Like the one where Jesus work on water, never understood that one, maybe Jesus could fly, or maybe he could run really fast over water like a lizard dose.  

 

but seriously, I do think it’s farcical to acutely think that “god” crated us and every thing around us, and I do find it hard to believe that people will put there beliefs in to something that was writing in a time where people believed the world was flat and 80% of people couldn’t read or write the language they where speaking. Most of the time in history  “GOD” or praying to god has been something that people did in time of need, hopping and praying that “He” will save them, but unfortunately he never has. Never once has he save the innocent. Most of the time “GOD” has simple been away to promote war and evil. And not much has change today I see. “In the Name of God”.   

 

I think it’s rather primitive to believe the bible, as I said before, it was a deferent time, people didn’t understand a lot of what was going on around them, so yes in there primitive minds they came up with one. What they could not explain must have come from god. I can certainly understand how they came up with these thyrosis.  For example  In Australia the local aborigines believe that a large snake carved out the earth.  Is this true? NO it’s a story about there dream time, or something. It’s a fascinating story about there culture, and you can find storeys like this all around the would, the bible is just anther story book.      

 

  But I can understand some of the massagers that it gives out, like be kind to people, forgive other people that have done wrong by you.  If people focused on theses parts, instead of the literal things the world would be a better place. Also like the sense of community that churches have given to people are not all a bad thing as well, as long as there not used to prompt someone’s engender in the game of god.     

[Sam 163]

Since this is a SimCity fan forum I thought this article at Not Exactly Rocket Science might be interesting.

Do you think you are a good city designer? Your transport networks are a model of efficiency? Maybe we will be playing the next  Sim City in a petri dish rather than on a computer.    Slime mould attacks simulates Tokyo rail network.   Another example of how the theory of evolution can be used to provide practical solutions to real world problems, and how no intelligence is required to produce an appearance of design.

Edit: citation for the Science article too -

Atsushi Tero, Seiji Takagi, Tetsu Saigusa, Kentaro Ito, Dan P. Bebber, Mark D. Fricker, Kenji Yumiki, Ryo Kobayashi, and Toshiyuki Nakagaki (22 January 2010), Rules for Biologically Inspired Adaptive Network Design,     Science 327 (5964), 439. [DOI: 10.1126/science.1177894]

    Human municipal transportation engineers might learn design strategies from the lowly slime mold.

quote>

[MandelSoft 2,769]

First of all: you don't have to agree what I'm saying here. I'm not religious in any kind (maybe I'm just too sceptic), but I do respect anyone who's believing in anything.

Now to the point, this is my point of view to evolution and creationism:

• Evolution makes predictions and therefore it can be proved or disproved. Creationism doesn't make any prediction, and is therefore it has no scientific use.
• There are some proofs that are supporting evolution: a lot of bones of pre-historic creatures (and even other species of humans) discovered all over the world, and there's even proof of evolving bacteria. How can creationism explain that?
• Evolution is based on pure logic, while creationism looks to be based on one book.
• Today's microbiology wouldn't make sense without evolution.
• It's more likely that everything that we see today started out as something simple and from time to time it gets a bit more complicated until we have such a complex world after billions of years then that we are just created about six-thousand years ago.
• To continue the last argument; there's a lot of proof that the Earth is much older than six-thousand years. Creationism can hardly explain geological processes like earthquakes, volcanoes and moving continents (yes, they are moving at a rate of a few inches per year). Neither does evolution, but geology does.
• I'm in doubt how "valid" the Bible is (but then again, I'm quite sceptic. I don't ment to hurt anyone). Maybe we shouldn't take it literally.
• Evolution doesn't explain how life began. It was never ment to do that; it only describes the development of life.
• I see parrallels of evolution in the development of our civilazation (we are developing from time to time), economy (Successful companies "eat up" smaller companies (in plain English: they are buying them) and grow. Unsuccessful companies "get eaten" (in plain English: they get bought by another company) or "die" (they go bankrupt)) and even in SimCity (Sucessful cities grow, unsuccessful cities die).
• One critic is that evolution is a random process, and therefore can't create complicated thing like our eyes. I have to make a correction here: evolution is a semi-random process; mutations are random, but due to natural selection, there is some logic in the process, making development going in a logical direction. For instance, rabbits that run faster are more likely to escape from predators than slower ones. Because those slow rabbits don't survive, it will lead to a development of new generations of slightly faster rabbits. Even simple things can become very sophisticated, by evolving a certain part of the body slightly more sophisticated than the previous generation (like eyes, they maybe started as a few cells sensing light. The better the eye of the creature is, the better it can spot food or danger.

So I believe that evolution is more likely to be true than creationism.

Best,
Maarten

[Wreckingball Man 10]

I believe evolution is no more than a theory. No one who is pro-evolution has been able to answer the most fundamental part of evolution. I want to know how I would evolve. maybe if I spend enough time in the water and dozens of my descendants do, then maybe one of the generations will somehow end up with gills. I am asking this question to people who have doctorates in Biology. They will tell me what I need to survive in water. But they always avoid the question of how do I obtain these things, and how do the generations after me get these.

I also understand that species gain adaptations depending on what kind of environment they're in. But species do not change into other species. Fish don't grow legs over many generations just to walk out of water. Every animal has its niche in an ecosystem and food chain. so why would a fish walk out of water to join another ecosystem where it doesn't belong and possibly have no food.

even if this fish did walk out of water how would it know to walk out. How would it know how to walk. how would it's body know to build an adaptation like legs to walk on dry land which it knows nothing about or has never been on. there has to be a decision somewhere. we humans can't make a decision to grow gills. the ocean may be a better place to live. I don't understand how it would work.

and I know that only animals with the best adaptations survive. but wouldn't it be a better adaptation to just stay in the water and develop a more efficient digestive system. but how would it develop a better digestive system without some choice being made?

[Meg 368]

Originally posted by: Wreckingball Man

Fish don't grow legs over many generations just to walk out of water. Every animal has its niche in an ecosystem and food chain. so why would a fish walk out of water to join another ecosystem where it doesn't belong and possibly have no food.

even if this fish did walk out of water how would it know to walk out. How would it know how to walk. how would it's body know to build an adaptation like legs to walk on dry land which it knows nothing about or has never been on.quote>

It's called a snakehead fish.  or a frankenfish, depending on where you are from.

[Duke87 1,070]

Well, one fault in your logic here is that no conscious decision-making is inherently necessary for things to change. It can happen purely be chance.

As for the "fish walking out of water"... well, that's a misstatement. It would have been a gradual development, not a sudden change. Insects and worms came first. More complex land animals then later came from amphibians.

On another note, if you want to see something awesome, check this out.

[fukuda 351]

I believe evolution is no more than a theoryquote>

Indeed

No one who is pro-evolution has been able to answer the most fundamental part of evolution. I want to know how I would evolve.quote>

That's impossible to foresee, evolution depends on several dynamic factors: the environment the living being lives in, the genetic substrate (that's a very important one, evolution is mostly about recycling and transforming existing stuff instead of creating new things)

maybe if I spend enough time in the water and dozens of my descendants do, then maybe one of the generations will somehow end up with gills.quote>

That'll be pretty hard. Even though there are humans born with gills(some babies are born with open holes in their necks in a shark gill-like fashion, a chordate ancestry gift..), developing gills seems pretty unprofitable.

Take a look at all the mammals living in the sea, none has developed gills. They all have improved physiological solutions to retain more oxygen or lower their oxygen intake needs, developing gills is just a too biologically unfavorable change. It requires radical changes in anatomy and several systems at the same time and, as I said above, evolution is more like recycling stuff than doing radical changes (radical changes have higher chances to screw things up as evolution is not a sentient process and is unable to foresse what changes might be useful, and moderate changes have higher chances to revert to the "normal" state if the change is no longer useful).

Changes like improved hemoglobin or new duplicated machinery in red blood cells, coupled with a contractile spleen (like sea lions) and ischemia protection are way more likely than gills.

I am asking this question to people who have doctorates in Biology.quote>

Well, sorry but I don't have a doctorate in biology , doctors are busy creatures

But they always avoid the question of how do I obtain these things, and how do the generations after me get these. quote>

Gene duplication, exon reordering, lucky recombination, changes in regulation domains, transposon introduction... there are lots of mechanisms to generate new proteins and morphologic diversity in living beings, especially in animals and plants.

But species do not change into other speciesquote>

Why not? An entire duplication or triplication of the genome prevents an entire population from interbreeding with another, and it's a relatively fast and easy change, for instance.

Fish don't grow legs over many generations just to walk out of water. quote>

Nobody is saying that the structures that are now being used as legs were used in the past as such. The recent function of structures does not need to have a direct relationship with the older one.. Wings weren't used to fly back in the day when they were used as arms and arms weren't used to walk back in the day when they were used as fins to swim in muddy water.

Every animal has its niche in an ecosystem and food chain. so why would a fish walk out of water to join another ecosystem where it doesn't belong and possibly have no food. quote>

Because ecosystems are not static things at all. A fish may find food in a new ecosystem if he's pushed out of the river by new predators or its food developed poison against him, and who knows, he may be lucky and find prey that are completely defenseless against him.. or not. Living beings move and expand through different environments nowadays.

even if this fish did walk out of water how would it know to walk out.quote>

It wouldn't. walking didn't just appear out of the blue (even though simple walk requires small neuron reflex circuitry similar to swimming). Fishes probably just were barely able to move out of water at first, but attacking prey standing next to the water in a crocodile-like fashion would work anyway.. No need to run out of water.

how would it's body know to build an adaptation like legs to walk on dry land which it knows nothing about or has never been on.quote>

Fish developed "feet" bones while still in water, not to walk, but to swim more accurately. The body knows nothing, it doesn't build adaptations out of will.

there has to be a decision somewhere. we humans can't make a decision to grow gills.quote>

Decision? To change the regulation domains of a Hox gene? Fish evolved bony fins for millions of years before going out of water, it didn't happen overnight.

[mylife.103 16]

OK i would like to say a thing i noticed. The Nazis belived in evolution. funny isn't it? How the evil ones belive in evolution and the good ones usaly belive in creationsim. Another thing, the only thing that can make somthing change is exposure to certain chemiicals or rocks. Such as chlorine, uranium, and other chlor- chemicals.

[astronelson 339]

Originally posted by: mylife.103

OK i would like to say a thing i noticed. The Nazis belived in evolution. funny isn't it? How the evil ones belive in evolution and the good ones usaly belive in creationsim.quote>

Your point? Politics has nothing to do with biology.

Oh, and Creationism hereby loses through Godwin's Law.

Another thing, the only thing that can make somthing change is exposure to certain chemiicals or rocks. Such as chlorine, uranium, and other chlor- chemicals.quote>

UV light can cause random mutation too. And that's pretty much everywhere. So can the background radiation caused by the decay of unstable isotopes of common elements like Oxygen.

[krbe 193]

Originally posted by: mylife.103

OK i would like to say a thing i noticed. The Nazis belived in evolution. funny isn't it? How the evil ones belive in evolution and the good ones usaly belive in creationsim..quote>

I'm pretty sure that the Spanish Inquisition "believed" in creationism if they had ever had the choice. And I wonder what the Catholics that ran the schools in Ireland taught their pupils. Isn't it funny how the evil ones "believe" in creationism? 

[Boggy1 45]

mylife.103: No. Just. No.

I'm in one mind to delete your post; because it HAS to be trolling. I refuse to believe anyone can be that stupid.

[morriswalters 16]

Originally posted by:

Wreckingball Man

I believe evolution is no more than a theory. No one who is pro-evolution has been able to answer the most fundamental part of evolution. I want to know how I would evolve. maybe if I spend enough time in the water and dozens of my descendants do, then maybe one of the generations will somehow end up with gills. I am asking this question to people who have doctorates in Biology. They will tell me what I need to survive in water. But they always avoid the question of how do I obtain these things, and how do the generations after me get these.

 

Your very first line is correct. Your second thought is essentially unknowable, to  know that you would have to know where you started and as what. Perhaps God might know the answer but  no man could.  Your timeline is to short  for  the change you want to see.  Think millions of years.  And  hundreds of thousands of intermediate steps.  If you wish to have a dialog with a Doctor of Biology  then goto your local University and talk to one.  However I should tell  that there is a price to be paid and that is gathering sufficient knowledge to be able to have a cogent discussion of the issues.

I also understand that species gain adaptations depending on what kind of environment they're in. But species do not change into other species. Fish don't grow legs over many generations just to walk out of water. Every animal has its niche in an ecosystem and food chain. so why would a fish walk out of water to join another ecosystem where it doesn't belong and possibly have no food.

 

Again it's a timescale issue.  Fish just don't suddenly grow legs and walk.  Perhaps a good starting point are two modern examples of  Natural Selection.  The first would be dog breeding.  Most modern dogs effectively have only existed for 300 years or so.  Look at the variety that exists today. If you want the answers to your question start by understanding how this happened.  The second example is one much harder to  study since it requires the use of microscopes and a lab.  However you can find a lot of info on the web about these. Antibiotic resistant infections.  Certain forms of TB and MRSA to name two.  Understand them, it's in your own best interest.  Both can kill you.  And finally one for fun.  Look up research in Russia on domesticating Foxes, very interesting.

even if this fish did walk out of water how would it know to walk out. How would it know how to walk. how would it's body know to build an adaptation like legs to walk on dry land which it knows nothing about or has never been on. there has to be a decision somewhere. we humans can't make a decision to grow gills. the ocean may be a better place to live. I don't understand how it would work.

and I know that only animals with the best adaptations survive. but wouldn't it be a better adaptation to just stay in the water and develop a more efficient digestive system. but how would it develop a better digestive system without some choice being made?quote>

 

You wish to see a direct connection between the fish and the mammal.  How can one species evolve into another.  I don't know. Neither does anybody else.  Again the question you ask is essentially unknowable.  Nobody has seen it happen.  It takes too long.  The theory of evolution is simply a statement of how the process might work, supported by a large body of evidence.  You can see possible solutions in animals alive today.  Sea Otters, Seals, and Dolphins.  All three are mammals, all three with varying adaptations to surviving in the Ocean.  Are they coming or going or deadends?  I have no idea.  But if you wish to meet in a million years we might find out.

Your last question shows your basic lack of understanding of the whole process.  There is no better!  There is what works and what is lucky.  Given a lack of competition almost any trait might survive.  Ask yourself why the koala became what it became, requiring what charitably can be called a specialized diet.  I wish you good luck on the search for truth.  But remember truth requires hard work and is difficult to find.

[morriswalters 16]

Originally posted by: mylife.103

OK i would like to say a thing i noticed. The Nazis belived in evolution. funny isn't it? How the evil ones belive in evolution and the good ones usaly belive in creationsim. Another thing, the only thing that can make somthing change is exposure to certain chemiicals or rocks. Such as chlorine, uranium, and other chlor- chemicals.quote>

I believe your sense of fractured history is incorrect.  I don't remember that evolution was given any thought at all.. They believed on the other hand in a discredited science called Eugenics, a perverted form of genetics.  For instance they would probably have removed you from the gene pool to improve the species.  In terms of mutagens, sunlight would be one as well as any other energetic particle that you can think of.  You should tan early and often.  Get burned occasionally it improves the effect.

[Odainsaker 2,133]

Originally posted by: mylife.103

OK i would like to say a thing i noticed. The Nazis belived in evolution. funny isn't it? How the evil ones belive in evolution and the good ones usaly belive in creationsim. Another thing, the only thing that can make somthing change is exposure to certain chemiicals or rocks. Such as chlorine, uranium, and other chlor- chemicals.quote>

Uh oh...the Nazis believed in breathing air--even Hitler liked to inhale and exhale oxygen several times a minute everyday.  Since Nazis are Evil, and if what they liked doing is Evil too, and if they liked breathing so much that they did it multiple times a minute, then the act of breathing air must also be Evil.  Eeek...we must all hold our breaths so as not to be like the Evil Nazis!

Or perhaps we must find logic not based on fallacies or leading to absurdisms.

As for change...how again do we go from microscopic, unfertilized egg to fully-developed adult?

[Wreckingball Man 10]

Thanks for everyone who quoted me. I sound really stupid in my comment. I am not in AP Biology yet. I will take it for College credit though. so maybe then I can understand evolution better.

I was also wondering, if evolution doesn't explain the beginning of life. then is it possible that a creator designed things to change and adapt. and those little adaptations and mutations that biologists observe just kept happening until the one species by technical definition became another. this obviously couldn't solve the debate of seven days, or millions of years. this is obviously not a good hypothesis because according to the Bible everything was created in seven days, and evolution takes millions of years.

Maybe all these different devices were designed. For example, a leg designed to swim, and a leg designed to run. there are similarities but could one have come from the other?

I'm just giving my thoughts. I am not trying to disprove either creationism or evolution.

also i think I need more time to develop my thoughts. Thanks again for quoting me. LOL.

[astronelson 339]

Originally posted by: Wreckingball Man

Thanks for everyone who quoted me. I sound really stupid in my comment. I am not in AP Biology yet. I will take it for College credit though. so maybe then I can understand evolution better.quote>

Good plan.

I was also wondering, if evolution doesn't explain the beginning of life. then is it possible that a creator designed things to change and adapt.quote>

Ah, that would be Old Earth Creationism. Accepting that the earth is about 4.7 billion years old and evolution happens. As opposed to Young Earth Creationism, which says "Nahnahnah the bible says this so you're wrong".

Evolution, by definition, does not include the first lifeform, being a theory to explain changes in lifeforms. This does not mean, however, that science can't explain it. We have a theory for that too, called Abiogenesis.

and those little adaptations and mutations that biologists observe just kept happening until the one species by technical definition became another.quote>

That's evolution in a nutshell.

this obviously couldn't solve the debate of seven days, or millions of years. this is obviously not a good hypothesis because according to the Bible everything was created in seven days, and evolution takes millions of years. quote>

The bible actually says 6 days. A common mistake, but you'd think people would at least check what they're trying to use. Anyway, there have been experiments done using conditions very similar to those that existed around 4.5 billion years ago - same atmosphere, chemical balance, temperature, lots of lightning - and the scientists who ran the experiment got organic chemicals quite quickly. From there it's but a small step to basic single-celled organisms, that is, life.

Maybe all these different devices were designed. For example, a leg designed to swim, and a leg designed to run. there are similarities but could one have come from the other?quote>

Of course, except for the 'designed' part. Fins could be adapted to allow movement between pools of water without any change to their form. Animals better at moving over land would have a wider range of food sources and thus be more likely to survive and pass on their genes. Evolution is driven towards more efficient movement over land, and thus towards legs that can run.

I'm just giving my thoughts. I am not trying to disprove either creationism or evolution.

also i think I need more time to develop my thoughts. Thanks again for quoting me. LOL.quote>

No problem. Quoting is the easiest way to answer specific points within your post.

[Sam 163]

Originally posted by: Wreckingball Man

No one who is pro-evolution has been able to answer the most fundamental part of evolution. I want to know how I would evolve. quote>

Well I'm going to buck the trend and say something different to the other people who have responded (although they are all very knowledgeble people on the subject).

You will not evolve.

Individuals do not evolve. Only populations do. Individuals reproduce and the offspring have slight differences to their parents. The offspring's offspring reproduce and have slight differences again. The offspring's offspring's offspring reproduce have further differences. You get the idea.

When your mother's ovum and your father's sperm (that would eventually lead to you) were formed, their DNA was copied. Most of your DNA would be the same as you inherited from your parents, but there would have been some mutations too. For example, mutations in a single human have been numbered at around 120-160 on average. And that's not necessarily all mutations that actually occur, only particular types that can be measured.

You were dealt this genetic hand and that is the hand you play. There isn't much that will change that after your conception.

If you have children, your DNA from your germ cells (those that produce sperm or ova) will be copied to create sperm or ova and this may include some of the mutations you received above. Then there will be the mutations that occur during this copying that your child will inherit. This is how evolution occurs.

Generally you cannot acquire a somatic trait in your lifetime and pass it on to your offspring unless it is written into the DNA of your cells that produce your sperm or ova. Changes to the DNA of your somatic cells, eg cancer caused by you spilling a carcinogenic chemical on your skin, or from a virus, cannot be passed on to your children unless the changes are also in your germ cells that give rise to your children. There are some things that can change the DNA in your germ cells directly, such as a new endogenous retrovirus infection, but in proportion to the changes that occur due to mutation during DNA replication they probably aren't very common.

So the raw material for evolution (mutation) only or predominantly occurs at DNA replication to form a new individual. The answers to the rest of your questions follow from that. This is why you cannot spend time in water, grow gills and pass on gills to your children. If you did grow gills from your time in water they would not be passed on to your children, just like if you get a permanently broken nose, that is not passed on either.

There is also the matter of evolutionary historical constraint. An individual has a particular set of genes that depend on the genes its ancestors had. Its decendents have to survive within those constraints. If a new feature arises in an individual and is passed on to its children and spreads through the population, then only its descendents will have access to that feature. So if the individual was a human and acquired for example an enzyme to digest cellulose (not a feature humans currently have), you would not expect to see fish also acquiring that exact same trait. They will aquire traits of their own which they pass on to their offspring. This is why you end up with nested heirarchies. So humans work with genes that have historically been in the human lineage, and which their ancestors acquired, not those acquired by some other lineage after the lineages diverged (eg human evolution is more likely to be in the area of the brain and its abilities as opposed to aquiring bird wings, or even gills) . The direction of future human evolution is constrained by the path their ancestors followed in their past evolution. This is also why the classic creationist expectation of a "crockoduck" if evolution were true, is not actually a prediction made by evolution and would in fact be a falsification of it.

And the path is only the path once it has been trod. There is no "path" into the future, just a whole lot of potential directions the lineage could go in and a whole lot that the lineage cannot go in. Which they end up going in is not predetermined, it is the result of circumstances.  Evolution does not need foresight. It doesn't plan ahead. It doesn't give organisms what they need. Organisms get what they are dealt and live or die (or rather die sooner or die later), they reproduce successfully or they don't, depending on their dealt hand and their circumstances.

Some of the changes in recent human evolution relate to linguistic ability, genes that allow digestion of lactose in human populations that don't historically have genes for the ability to digest lactose, as well as sensory perception and metabolic changes relating to blood pressure in some East Asian populations. Others include resistance to diseases, such as malaria.

Previous people posting in this thread gave links to some YouTubers who make good videos explaining evolution. DonExodus2 is one of the ones I find most informative. He is a career research scientist in the field of evolution and has a doctoral degree from UNC. He speaks very fast in his videos but he explains things well. I particularly recommend his latest video on http://www.youtube.com/watch?v=OfybuMJVWj0. He also references and links to a recent paper on human frameshift mutations.

[MandelSoft 2,769]

Evolution is overall a slow process, but sometimes there are severe changes in the envoirment, that lead to mass-extinction. There were a few periods in Earth's history that large groups of organisms died:

- At the end of the "Carbonic Explosion" about 400 million years ago. In this time, the strangest creatures swam in our oceans. Due to a sudden climate change, a large part of the organisms got killed. That's why there are not so much body designs (look at all creatures with a spine. They all got (or have signs that they were there) four limbs, two eyes, two ears, one nose, one mouth, one heart and one brain. This is because all spined creates evoloved out of one creature with a spine, that survived this period of extiction.

- 250 million years ago, 95% of all life died, due to two sudden climate changes. First, the climate suddenly changes to hot, and a 'little' later into cold. All creatures that were adapted to the hot climate, freezed to death.

- 65 million years ago, more than 60% of the creatures (including the dinosaurs) died. There are different theories how this happened. The most common theory is that an astriod about 10km (that's a big one) in diameter crushed into the Earth. But there are theories that persume that massive volcano eruptions causes these creatures their death.

These sudden changes lead to changes in the ecosystem, and what may be a disadvantage in the first situation, may be an advantage in the following situation, or vice versa. Dinosaurs may have died, because they where too big. Large creatures need large amounts of food. But when food runs out, these creatures die. Mammals, which were quite small in this period, survived due to their small size.

The catastrophic events in the past, may have helped us to be the dominant species on the planet today.

Best,
Maarten

[fukuda 351]

Maybe all these different devices were designed. For example, a leg designed to swim, and a leg designed to run. there are similarities but could one have come from the other? quote>

Legs don't just magically appear during your embryonic development, there is a building plan. Length and shape of bones and muscle position are controlled by cell migration and signal release by other cells(veins just follow the other cells and nerves follow muscles). How far a cell goes through your leg depends on what is going on in the nucleus and which cells exchanged information with it on its way.

I'll give you a relatively simple example, how is bone length controlled? Using a sand clock model. Let's say that your cell received an external signal to build up lots of a molecule, this molecule binds to a gene and causes the cell to growth more in a given direction.

After a second signal has been received from a neighboring cell, the gene coding that molecule is blocked and the cell starts to grow in that direction. Your bone is growing and getting longer and longer (we're talking about thousands of cells growing at the same time) but this molecule is also getting destroyed by cell machinery at the same time, and cell duplication just lowers the amount of that molecule every time the cell divides to increase your bone's length. Under a given amount the molecule no longer causes cell duplication and bone elongation stops.

Just slightly changing the shape of that molecule would make it easier or harder to destroy by the cell machinery, resulting in a longer or shorter bone, or just changing the DNA in the place where the molecule binds to the gene would cause a similar effect without modifying the molecule itself..

The same kind of effect also controls the diameter of bones. And combining the effects of several signal pathways and cells you get a complex net of interactions that is the basis of body development. As I said earlier evolution is lazy and the same gene is used for different things, so usually modifying one molecule induces changes in other tissues, this usually isn't good news and a mutation causes havoc and misfunction, but sometimes it allows fast development of new appendages and abilities.

In the evolution of bony fins bones get longer, shorter, wider, new fingers appear.. many driven by this process of changing promoter affinity

Appendages ain't "designed" to fullfill a task, they get changing shapes (in fact no shape lasts a long time due to genetic drift) and these useful are selected and the negative ones are eliminated (99% of big appendage mutations are deletereous). The building plan is modified by mutations and both natural selection and genetic drift decide what remains

*Keep in mind that I used a (very) simplified model, there are more processes involved IRL, but that's a basic view of how some morphogenetic factors work, and sorry about the crappy pic, I ddn't have much time to work on it

[Wreckingball Man 10]

Thanks again for quoting me. I love ST.

I'm still on the fence though. No offense to any of you but I'd rather wait to make up my mind. I feel that after I take AP biology and a few courses in college, I'll then have enough info from reputable sources to make the best decision.

Thank you Fukuda, Sam, Astronelson, morriswalters, and yes Meg, I have heard of a snakehead fish. *Sarcasm not intended* I was more interested in what causes a fish, like a snakehead, to develop legs. And also why it would walk out of water. However, I feel that others have answered this question suffentiently.

[fukuda 351]

I'm still on the fence though. No offense to any of you but I'd rather wait to make up my mind. I feel that after I take AP biology and a few courses in college, I'll then have enough info from reputable sources to make the best decision. quote>

No problem . Feel entirely free to post if you are interested in or want to learn more about biology or evolution-related topics.

- At the end of the "Carbonic Explosion"quote>

I fear you're talking about the "Cambrian Explosion" instead. It did not involve dangerous reactions with hydrocarbons.. well I think it didn't.

[MandelSoft 2,769]

- At the end of the "Carbonic Explosion"quote>

I fear you're talking about the "Cambrian Explosion" instead. It did not involve dangerous reactions with hydrocarbons.. well I think it didn't.

quote>

Sorry, my mistake. I'm not good at the names of ancient time periods of the Earth

[A Nonny Moose 8,261]

The film Inherit the Wind is running at 0100 EST tonight on TCM channel.

[Sam 163]

The Neanderthal genome has been sequenced and the draft genome is presented in the 7 May 2010 issue of Science. The researchers sequenced over 3 billion nucleotides from three individuals. They've also compared them to five individual humans and have identified a number of genomic regions that may have been subject to positive selection in modern humans.  The results are interesting.

Two of the papers are freely available to site visitors and there is also a special online presentation:

http://sciencemag.org/special/neandertal/

A Draft Sequence of the Neandertal Genome. R. E. Green, J. Krause, A. W. Briggs, T. Maricic, U. Stenzel, M. Kircher, N. Patterson, H. Li, W. Zhai, M. H. Y. Fritz, et al. (2010) Science 328, 710-722

[Duke87 1,070]

Under the assumption that there was no geneflow from Neandertals to the ancestors of modern Africans, theproportion of Neandertal ancestry of non-Africans, f, can beestimated by the ratio S(OOA,AFR,N1,Chimpanzee)/S(N2,AFR,N1,Chimpanzee),where the S statistic is an unnormalized version of the D statistic(SOM Text 18, Eq. S18.4). Using Neandertals from Vindija, aswell as Mezmaiskaya, we estimate f to be between 1.3% and 2.7%(SOM Text 18). To obtain an independent estimate of f, we fita population genetic model to the D statistics in Table 4 andSOM Text 15 as well as to other summary statistics of the data.Assuming that gene flow from Neandertals occurred between 50,000and 80,000 years ago, this method estimates f to be between1 and 4%, consistent with the above estimate (SOM Text 19).quote>

So I'm maybe about 2% Neandertal. Heh. Cool!

A striking observation is that Neandertals are as closely relatedto a Chinese and Papuan individual as to a French individual,even though morphologically recognizable Neandertals exist onlyin the fossil record of Europe and western Asia. Thus, the geneflow between Neandertals and modern humans that we detect mostlikely occurred before the divergence of Europeans, East Asians,and Papuans.quote>

Well, that's fascinating, but there seems to be something obvious that isn't mentioned and wasn't looked at here. One would think that this gene flow would have occured in the region where Neandertals and Africans first met. Look at a map. Where would that be? Signs point to the Arabian Peninsula.

So then, guys.... why no Arabs in the study, eh? Where do they fit into the picture? And how about Native Americans? There's unexplored potential here!

[A Nonny Moose 8,261]

Unfortunately, the universe of discourse in these studies is so large that, even with modern computing capability, this may turn out to be an NP-complete problem that can never be solved.  This is one of those cases where the more we know, the more there is to find out.

Recently, I saw a show on the NG channel where a study was made of individuals on the east coast of the U.S. with selections from as many visible minorities as possible.  The resulting genome showed that everybody is related to everybody else with a congruence in excess of 99%.  So who cares about local climate adaptions like skin colour?  I grew up in a time when race mattered, but, thank heavens, my kids are colour blind in that area.

[Duke87 1,070]

Originally posted by: N_O_Body

The resulting genome showed that everybody is related to everybody else with a congruence in excess of 99%.quote>

That's a misleading number. Aren't we something like 98% genetically the same as chimpanzees?

So who cares about local climate adaptions like skin colour?  I grew up in a time when race mattered, but, thank heavens, my kids are colour blind in that area.quote>

There's more to race than skin color, you know. The other physical differences aside (ever met a really tall Asian person?), there are genetic differences affecting all sorts of things. Some races are more or less prone to certain ailments than others, particularly with regard to cancers and genetic disorders. Africans, for instance, are more likely to have sickle-cell anemia... however, the very same trait gives them a degree of resistance to malaria that other races do not posess.

There are perfectly good scientific and medical reasons to want to study these things... unfortunately, modern political correctness prefers to deny that such differences exist over fear that they will be used to make arguments that some races are superior to others.

This, however, is a purely emotional problem.... it is absurd to deny that we are different, and there is absolutely no reason why we cannot acknowledge our differences ("celebrate diversity!") while at the same time accepting that we are all equally human.

[fukuda 351]

That's a misleading number. Aren't we something like 98% genetically the same as chimpanzees?quote>

That 98% mainly refers to the coding sequence of genes, not the overall DNA.

Genes themselves have repair machinery and won't change that much in small amounts of time. we don't use genes to do that kind studies, we mainly use non-coding repetitive sequences called microsatellites that are highly variable through time and show may more difference between humans people. They bear no biologic information whatsoever though, they're just used by us as measuring units.

The other physical differences aside (ever met a really tall Asian person?)quote>

I've met several of them, why?

This, however, is a purely emotional problem.... it is absurd to deny that we are different, and there is absolutely no reason why we cannot acknowledge our differences ("celebrate diversity!") while at the same time accepting that we are all equally human.quote>

Indeed