What Darwin Never Knew

What Darwin Never Knew

2009, Science  -   208 Comments
8.35
12345678910
Ratings: 8.35/10 from 69 users.

What Darwin Never KnewEarth teems with a staggering variety of animals, including 9,000 kinds of birds, 28,000 types of fish, and more than 350,000 species of beetles alone.

What explains this explosion of living creatures-1.4 million different species discovered so far, with perhaps another 50 million more to go? The source of life's endless forms was a profound mystery until Charles Darwin's revolutionary idea of natural selection, which he showed could help explain the gradual development of life on earth.

But Darwin's radical insights raised as many questions as they answered. What actually drives evolution and turns one species into another? And how did we evolve? On Charles Darwin's 2009 bicentennial, and the 150th anniversary of the publication of On the Origin of Species, NOVA reveals answers to the riddles that Darwin couldn't explain.

Stunning breakthroughs in a brand new science-nicknamed evo devo - are linking the enigma of origins to another of nature's great mysteries, the development of an embryo. To explore this exciting new idea, NOVA takes viewers on a journey from the Galapagos Islands to the Arctic, and from the Cambrian explosion of animal forms half a billion years ago to the research labs of today.

Here scientists are finally beginning to crack nature's biggest secrets at the genetic level. And, as NOVA shows in this absorbing detective story, the results are confirming the brilliance of Darwin's insights while exposing clues to life's breathtaking diversity in ways he could scarcely have imagined.

More great documentaries

Subscribe
Notify of
guest

208 Comments
Newest
Oldest Most Voted
Inline Feedbacks
View all comments
DustUp
DustUp
6 years ago

Ignorance is bliss. 1) No "Mod" shows on my display. Nor can I do a search. Possibly due to the Script Blocking and other Blocking software I have running in attempt to keep various sites from polluting my computer. I would imagine there are others who can see "Mod" as well.

2) Too often so called scientists "find" what they want to find, regardless of what evidence may not definitively show. And when they, like most news programs, or govt, only provide the limited edited information that supports what they want you to believe. And if people are inclined NOT to consider that there may be much more to the story than what was presented... You then get a bunch of arrogants who limit themselves to what they want to believe, like they actually know something, which they clearly cannot, limiting themselves as they do; then using whatever venue they can find, like this one, to puff their ego at other's expense.

3) If one specie can become an entirely different specie as the UNPROVEN THEORY presents, then how is it that a healthy viable organism produced by the crossing of two slightly different species, such as the crossing of a horse and a donkey to get a mule, cannot even reproduce? And we are supposed to believe that DNA mutates indefinitely and that organism will still reproduce?

4) It seems the better theory with actual hard and fast evidence to back it up is that when a specie deviates or adapts too far from its original, it either reverts back or dead ends.

5) If nature is neither good nor evil, it just does what it does, then how is it humans, being part of nature, especially Marxist socialists-communists can be so evil? Desiring to force all to live as they say, limiting the freedom of all AND ending competition to their companies and their rule. Killing off 10 times as many in Europe as Hitler was purported to exterminate of Jews. Then there are the Asian versions which killed many 10s if not 100s of millions. Then the African version. Even if a better system comes along which it did long before in at least one Native American nation but most notably when the US Constitution and Bill of Rights were signed. Yet people with limited information with the propensity to not investigate further, fall prey to their emotions which are manipulated via propaganda that the socialists are the ones who care and that is the direction of our social evolution. Despite the reality it has proven to fail mankind horribly throughout history.

6) Despite the failings of Darwin and his theories, they are still promoted heavily by the Marxist socialist-communists, Why? Simply because they don't want God, nor any higher power, or sense of right and wrong, getting in the way of what they want to do. Do they want to "take care of the poor" as they claim? Not at all. There wouldn't be any poor if they got rid of the welfare departments and just gave all that money wasted in govt, to the poor. They need more poor to keep voting for them. The purpose of open borders.

7) Look up and read what is chiseled into the Georgia Guidestones, what those behind the promotion of socialism, for what they want to do to you.

8) What does politics have to do with the theory of evolution? These days, everything. Wouldn't surprise me in the least if that had always been the case.

Peter JC
Peter JC
9 years ago

"He's not the messiah, he's a very naughty boy", Life of Brian

Guest
Guest
9 years ago

What are you dips going to bring up? You don't know who I am do you? What I am is a molecular biologist who was taught under the best teacher, like him, I don't believe in a "tree of evol0lution."

Fish
Fish
9 years ago

If the creationist would like to have all their questions answered about evolution, read 'Why Evolution is True' by Dr. Jerry Coyne

Wassee
Wassee
10 years ago

Unfortunately, most people consider science in general and evolution in particular to be an attack on religion / God. This thought arises from a lack of understanding of God in the first place. Also, a poor conception of God / Creator is what leads people to reject God. For example, It is like saying "I don't believe in air because when I flap my arms I do not fly". If one understood what air is (through science) they wouldn't make this claim. In fact, once they learn about the properties of air (through science) and how it affect us, their belief in air will only strengthen. Most of today's religions portray a distorted picture of God. And when Atheists reject God, they are just rejecting that distorted image of God and not the reality of God.

I am a firm believer in evolution. And when I learn about the intricacies and marvels of nature such as evolution, it only strengthens my faith in the Lord of the worlds. And I exclaim "Glory be to Allah".

Fenris
Fenris
10 years ago

I hope that you don't believe that "God" (thinking in form of existing religious view) created us, space and etc.

Religion is just human consolation that he understands world around him and has some rules to obey so he can get some kind of reward after death.

'Life is not the opposite of death. Death is the opposite of birth. Life is eternal."

DeShaun Williams
DeShaun Williams
10 years ago

Over and over again evolution has been a theory proven wrong

Carl Hendershot
Carl Hendershot
11 years ago

Proves nothing. Again beating a dead fish and asking it to talk. Human ape fused chromosomes paradigm.

gsjikwblao
gsjikwblao
11 years ago

OK. Your point is well taken. I do not know how the stress in an organism could trigger a shift in its' physical nature and I am aware that there may be no "will" written into the DNA for this kind of change. But there is strong evidence, supported by established fact in the field of human psychology that collective stress triggers a shift in consciousness. Since it is possible that animals experience some form of stress in a difficult enviorment I thought the same may be true in "physical" evolution. This would mean that the mutations are ordered by the organism in need of a change and that the "mutations" are not random. Is it an established fact that mutations are random? If so, is it not possible that stress could alter one of the continuously emerging mutations to be just what is required?

Guest
Guest
11 years ago

objection: Schopenhauer stated wat it IS, Darwin discovered how it WORKS

Marleonetti
Marleonetti
11 years ago

This video disproves evolution and makes a great case for creation resulting from an immediate change through on/off switches as opposed to a slow evolving change.

oQ
oQ
11 years ago

What Darwin never knew?
What the world would end up doing with his theory.
1i

Saurabh Dey
Saurabh Dey
11 years ago

BUT WHY ???
All true. The DNA being same, the switches that turn on and off, which means if it was possible to control the switches, one life form cud be turned into another by will. Then, understood that there is another strand of DNA which orders the switches. All amazing and previously believed by me.
BUT the question still remains. According to the fish theory, the one that walked into land and thus developed limbs, we can understand that the basic need for survival led to a will, a rather strong will, even if for that moment(as animals do not have imaginative fear of future danger), and this will led to a concious effort for change in DNA, probably the deciding DNA decided to turn on a few switches to convert fins to limbs, it is understood.
But in the apes, natural phenomenon, like acts of survival(like in the fish), will not trigger switches to develop such muscles of the brain which actually tell us to fight for others, to share, to hate, to conserve for greed. These things go against the law of nature, which is the primary reason why we are conciously destroying the planet unlike any other creature which lives in harmony quite unconciously.
Why wud an act of natural selection work for its own destruction by giving a primate something we call imagination. It isnt for survival. Apes infact are very much capable of survival, being quite strong, and have long lives.

We are constantly looking at the Darwin view that we are similar to apes, so we must have come from them. That's because the western past tells them that humans were ignorant in the past, and now science and knowledge is there so we are becoming better, humans are becoming more intellegent(from ape intellegence to human intel)

Why don't scientists think that it is agreed that things evolve, but one rule doesnt hold same for everything. When the DNA and genes are basically the same, AND THERE ARE SWITCHES provided the same way in ancient fossil creatures like in us, maybe all creatures existed at the same time. It was a matter of switches being on or off to decide what the creature wud look like and what will be its habitat, food, etc.

Why does any creature over a period of time have to evolve FROM another creature, and not by itself. The research isnt proving that humans came from apes. It just proves that humans and apes are similar, and how they are similar. But that cud mean that apes came from humans(those humans who refused to think and only thot of food and survival, mutated to apes)
There is a certain pre conditioning here. Those scientists who say that we find ape fossils but not human fossils to prove that apes existed before humans, and thus humans came from apes, shud see that in the recorded past, every culture used to cremate their dead, even egyptian common man(only the kings, etc went to tombs, pyramids), turning them to ashes.

Saurabh Dey
Saurabh Dey
11 years ago

White europeans moved to america. Europe was cold but america was warm. The Mayans there looked different. But, soaking the sun still gives the whites a sunburn. There looks haven't changed in the warmer region with plenty of sun exposure, different air and habitat, even after almost 500 yrs. The african slaves, considering they came from a hotter, humid, tropical climate with jungles of huge diversity in life, they look the same, havent grown fairer. The european families living in africa today who havent mated with anyone but their own race, look the same inspite of living in hotter climate. I do not reject transformation, but I feel it is not absolute, I think its subjective. Yes offsprings of different species mating, will be different, and also I also believe that the subconcious effort of a species to protect itself, to blend in, and to hunt better, would lead to change in its dynamics slightly. But that rat example was a bad one, The rat wud not mutate so fast, it will just avoid the black rocks. Plus animals do not have imaginative fear(its only for humans, that's why we save food and form civilization), animals have current fears, if the rat goes out during the day to scavage it will continue to do so every single day, not thinking that its gonna get hunted. They dont dive in to save their friends from getting hunted, or change their habitat. That is a human capability(ad to an extent is found in mamals during lactation). If I have to imagine the rat theory, I can think of a few possibilities :
1. The white rat tht went on the black rock and gets eaten, and another rat tht was watching it felt the pain and fear and wanted to be different, which led to the changes in her DNA while she was pregnant and led to the birth of slightly darker rat.
2. The black rock matter and the matter of rat's skin biologically interacted and saw a possibility of the rat getting hunted, so made changes in the DNA so that it could adapt. But that wud be unfair to the coyote. Nature is not unfair. Why wud the black rock only affect the rat's hair and not the coyote vision contrast.
I don't know much about Christian religious beliefs much, but Vedic system calculates the age of universe, circumference of sun and other scientific things very accurately and much before the western world. It seems logical, and scientific, so I'd also like to believe in other things it says like :
1. Everything is constantly changing, life, matter, energies, and nothing is absolute but the one conciousness. OK... it affirms that changes and evolutions keep taking place all the time.
2. It talks about dinosaurs(giant lizzards), the large fishes, etc.
3. It also points that humans have been on this earth in a much developed stage for a very long time. The fact that all ancient people, even animals as far as we know from all cultures around the world were cremated, and houses were built on top of other houses, and all waste metals were re melted and re used, is the reason why we dont have much archaeological evidence, only we find those where mass death suddenly happened and lands were ruined to an extent that microbial activity under the ground reduced to an extent that things got preserved.

I would give probability to both ideas under Scientific Logic, since we wern't present back then.
1. We came from apes, previously fishes - 50% OR
2. Including slight changes/mutations, the major lifeforms existed always - 50%

One thing where thr is no probability :
We know it all -0%, OR We will always be learning - 100% :)

Happy thinking.

dancingroads
dancingroads
12 years ago

Evolution by natural selection is a wonderful idea. Really powerful and wondrous. All life, all the vast variety of the natural world is intimately connected by common heritage. All life is part of a vast family tree descending back throught time. Those who wish to dismiss this idea, because it doesn't fit with the religious dogma of a book are doing manking a great disservice. Not only rejecting the evidence of the natural world but dismissing the power of science itself. It is truly shameful that there are those who to this day wish to replace this incredible idea with the shallow and ignorant belief that all life was simply placed here as it is by some supernatural being, the evidence of which there is not a single scrap of evidence.

agency108_media.
agency108_media.
12 years ago

how did the fish breathe when first coming out of water...

sarp kaya
sarp kaya
13 years ago

Arnold,
In addition to the radiation supplied by heavenly bodies impacting the planet there is of course another theory, well substantiated by the fossil record, that such impacts on a global scale actually clear the field for species that would otherwise not have made it with all the competition around.
It is quite clear to scientists that mammals would not have had any chance to develop if the meteor that wiped out the dinosaurs 65 million years ago had not hit the planet.
The evolvement of the human species therefore owes much to that single impact, fortunately timed very well for our sake. The geological history of the planet is full of such instances where conditions wiped out an enormous number of species, either en masse or gradually over time.
The majority of the people on this planet can not overcome their egos enough to be able to appreciate such harsh realities.

Arnold Vinette
Arnold Vinette
13 years ago

This was a very interesting program on DNA, what makes us human, and how switches in the DNA make every life form possible. What is interesting is how evolution is continuing everyday. This was sadly observed in the cases where brain development was cut in half and with muscular dystrophy.

However what we are not seeing is the changes of the brain leading to smarter humans. For instance what does the DNA of the brain look like for a scientist and a documentary programmer / videographer?

What other humans are being created that have exceptional mental, creative and physical abilities?

All in all very interesting work.

I would like NOVA to do a show on what is involved in creating a documentary like this. The entire process from concept to funding to script to filming to editing and the addition of special effects and the narrators voice. NOVA documentaries are so complex in the numerous details to bring a subject to life that I would enjoy seeing the entire process of creating one.

Arnold Vinette
Ottawa, Canada

Robert Allen
Robert Allen
13 years ago

To Voice of Treason

You're the one who is daft and let me add ignorant. "Think about it" is hardly an offer of proof.

VoiceOfTreason
VoiceOfTreason
13 years ago

Hey,

Natural selection is a myth.

Seriously, think about it.

It's bordering on daft.

Prix
Prix
13 years ago

@dread

Hello there!
It's nice to see that you made this connection but
can I clear some points out for you?

Chakra is mentioned in Hinduism FIRST.
Darwin refined and proposed it as a SCIENTIFIC theory rather than "chakra" which has nothing to do with evolution, what so ever. You might as well talk about Bible code and evolution.

Unknown to rest of the world? Please tell me what kind of information you have that points to Evolution proposed as a theory around rest of the world?

Btw, anyone can make vague connections. Even me, in Hinduism Rams servant Hanuman is half monkey and half human. Just because they made some vague connection does NOT mean they had any clue about evolution. I'm from India and I can confidently say that Darwin was a genius. And I would never make any comments about "west" or "white people". We are Homo sapiens and that's about it. Even Buddhas teachings just define humans as Humans and don't divide humans in any shape or form.

Theory of Evolution has nothing to do with white people or west. It's just science. The most powerful tool that changes understanding rather than a book that hasn't been changed since 2500 years ago.

dread
dread
13 years ago

Hello sarp kaya

The film quiet often gives credit to Darwin that what it spoils. though the WEST came to know Evolution through Darwin that does not mean that it was unknown to the rest of the world. that what i tryed to point out.

-listen to the narrator...
"It shook people up, changed the way people thought" "Darwin provided a proper scientific theory" etc; etc;

By the way We westerners have a long way to go.....

sarp kaya
sarp kaya
13 years ago

Evolution knows nothing about "west" or "east" my friend. Nor does it care about ancient mythologies, religions or other cultural and national divides. It seems you have some racial bones to pick with the "west" ? That is not the topic of this film.
Neither does evolution pretend to know how life began on this planet (a lot of people think it does). Philosophy or religion has nothing to do with evolution, or any other scientific activity for that matter.
If you are satisfied with Buddhism or Egyptology as the best way of explaining how you are what you are, then that is your problem my dear friend. Whatever rocks your boat. But that really is not the purpose of this discussion methinks...

dread
dread
13 years ago

hello, sarp kaya
its just that the WEST always want to & try to mislead the mass by stating that if not for them that the rest of the world would be blind or to say how great the white race(!!!i ain't no racist) is. & that sounds really sad.

After all Buddhism is not a religion its a philosophy. if you wish! read it to check.. also Buddhism is not the only teachings that mention 'bout evolution.. their are plenty of ancient source with similar thoughts like Egyptian etc;

sarp kaya
sarp kaya
13 years ago

Ohh thank you dread for this astounding revelation.
And to think that all these centuries we were fooled by science in to thinking that it could provide answers to such questions. All those shameless Nobel prize winning biologists, geneticists, paleontologists, archaeologists, astronomists and geologists had us fooled the whole time. What an atrocious conspiracy ! And I am sure they knew all along that the true answers were in Buddhism but they hid it from us. Off with their heads and burn their books is what I say !

dread
dread
13 years ago

Check Buddhism and the cycles(Chakra)of life..
-Though Darwin has been credited with the "best idea" regarding evolution.

Further more, the science's still have more question to be solved pertaining to evolution.. while Buddhism already have the answers for them too. checkman

sarp kaya
sarp kaya
13 years ago

I have taken several sections from 'The Blind Watchmaker' and 'The Selfish Gene' to show you that the causes of mutation are not unexplained as you believe. I have also added some other sections that further explain the process of natural selection in a basic way.

EVOLUTION basically consists of endless repetition of REPRODUCTION.

In every generation, REPRODUCTION takes the genes that are supplied to it by the previous generation, and hands them on to the next generation but with minor random errors - mutations. A mutation simply consists in +1 or —1 being added to the value of a randomly chosen gene. This means that, as the generations go by, the total amount of genetic difference from the original ancestor can become very large, cumulatively, one small step at a time. But although the mutations are random, the cumulative change over the generations is not random.

The progeny in any one generation are different from their parent in random directions. But which of those progeny is selected to go forward into the next generation is not random. This is where natural selection comes in. The criterion for selection is not the genes themselves, but the bodies whose shape the genes influence through DEVELOPMENT.

In addition to being REPRODUCED, the genes in each generation are also handed to DEVELOPMENT, which grows the appropriate body in the womb, following its own strictly laid-down rules. In every generation, a whole 'litter' of 'children' (i.e. individuals of the next generation) is born. All these children are mutant children of the same parent, differing from their parent with respect to one gene each.

In its most general form, natural selection must choose between alternative replicators. A replicator is a piece of coded information that makes exact copies of itself, along with occasional inexact copies or 'mutations'. Those varieties of replicator that happen to be good at getting copied become more numerous at the expense of alternative replicators that are bad at getting copied. That, at its most rudimentary, is natural selection. The archetypal replicator is a gene, a stretch of DNA that is duplicated, nearly always with extreme accuracy, through an indefinite number of generations.

Mutations are caused by definite physical events; they don't just spontaneously happen. They are induced by so-called 'mutagens' (dangerous because they often start cancers): X-rays, cosmic rays, radioactive substances, various chemicals, and even other genes called 'mutator genes'. Second, not all genes in any species are equally likely to mutate. Every locus on the chromosomes has its own characteristic mutation rate. For instance, the rate at which mutation creates the gene for the disease Huntington's chorea (similar to St Vitus's Dance), which kills people in early middle age, is about 1 in 200,000.

The corresponding rate for achondroplasia (the familiar dwarf syndrome, characteristic of basset hounds and dachsunds, in which the arms and legs are too short for the body) is about 10 times as high. These rates are measured under normal conditions. If mutagens like X-rays are present, all normal mutation rates are boosted. Some parts of the chromosome are so-called 'hot spots' with a high turnover of genes, a locally very high mutation rate.

Third, at each locus on the chromosomes, whether it is a hot spot or not, mutations in certain directions can be more likely than mutations in the reverse direction. This gives rise to the phenomenon known as'mutation pressure' which can have evolutionary consequences. Even if, for instance, two forms of the haemoglobin molecule. Form 1 and Form 2, are selectively neutral in the sense that both are equally good at carrying oxygen in the blood, it could still be that mutations from 1 to 2 are commoner than reverse mutations from 2 to 1. In this case, mutation pressure will tend to make Form 2 commoner than Form 1.

Mutation pressure is said to be zero at a given chromosomal locus, if the forward mutation rate at that locus is exactly balanced by the backward mutation rate. We can now see that the question of whether mutation is really random is not a trivial question. Its answer depends on what we understand random to mean. If you take 'random mutation' to mean that mutations are not influenced by external events, then X-rays disprove the contention that mutation is random.

If you think 'random mutation' implies that all genes are equally likely to mutate, then hot spots show that mutation is not random. If you think 'random mutation' implies that at all chromosomal loci the mutation pressure is zero, then once again mutation is not random. It is only if you define 'random' as meaning 'no general bias towards bodily improvement' that mutation is truly random. All three of the kinds of real nonrandomness we have considered are powerless to move evolution in the direction of adaptive improvement as opposed to any other (functionally) 'random' direction.

To this, we can add a fourth respect in which mutation is not random. Mutation is non-random in the sense that it can only make alterations to existing processes of embryonic development. It cannot conjure, out of thin air, any conceivable change that selection might favour. The variation that is available for selection is constrained by the processes of embryology, as they actually exist.

ez2b12
ez2b12
13 years ago

@ mvairavan

Well "it" doesn't exist really. This is a random process directed by natural selection. First we must consider that 99.99999 percent of the time, only slight variations occurr, like if eyes are the advantage then it will be the color of the eye, -which generally is not of any consequence.

Now once in a few hundred generations or even longer, the entire gene may be skipped. In this case the advantage is not passed on to an offspring and that offspring will probably not survive to reproduce as a result- viola, the issue is fixed now the vast majority of the species continues to pass on the advantage.

Now if the off spring that did not recieve the advantage is crutched up by society and continues to reproduce- that can be a weakness for that species. This is why people that practice social Darwinism (I do not, this is wrong in my opinion) say that retarded people or deformed people should be exiled or exterminated. The say they are a drag on the rest of societies resources and they may reproduce creating more and more persons like themselves therefore leading society into further and further decline.

All I have to say to these people is two words, Stephen Hawking. Look what we would have lost if this brilliant man had of been ostracized or descriminated against- but I am getting off on a tangent sorry.

My point is that most of the time, infact the vast vast majority of time the beneficial gene does get passed on, the copier does not make these types of mistakes very often at all.

Eventually it will though, and if it is a detriment- like the advantage not being passed on- nature will stop that genetic line through selection for death or at least no reproduction.

If it is a modification of the advantage, and that modification is beneficial nature will select that animal for life and reproduction. Make sense?

mvairavan
mvairavan
13 years ago

@sarp Kaya

"if they result in changes that benefit the organism in some way, they give that organism an “edge” over its competitors that will, in most cases, allow that organism to live longer and reproduce more than its competitors. "

Still this parts seems like a magic!!! If mutations are random(not perfect), then how can it determine this is what happened when they are born to pass it on.. As shown in this documentary, the hit ratio for this mutation seems very high resulting in creating an almost new variety or i should say different type of species as in the case of birds in the Galapagos

ez2b12
ez2b12
13 years ago

@ @ sarp kaya

Well, I really spoke to soon. You are right, in a way. The type of changes you referr to can change the way a species looks over time. And i guess every once in a while it makes a really big mistake and we get that leap forward that very seldom occurrs. But we still haven't determine the cause, just the mechanism.

We need to find out what causes this copier to make these mistakes, how random or not random is the pattern of when and to what degree the mistakes are to be made. I mean, I can't remember what the protien is that carries out this job of copying but I have seen animations of ther little buggar shootin' 'em out, does this thingy have some sort of internal sequence built in? If so we should see mutations occurring at the same time intervals over and over. Unless that sequences is like a code that repeats itself but is so long that it seems random to us, does that make sense to you? I don't know how to say what i want to say, darn my pitiful knowledge of mathematics!

Its like timing in a song, sometimes the pattern doesn't repeat it self or come back to start until the very last of the song. This makes it seem very scattered and almost like it is not related to itself enough to be called a song even, more like just random notes that are in the same scale but lack a specific melody. I play jazz and this is why a lot of younger musicians have trouble with jazz, timing-timing- timing. Anyone can make sound, music is sound moving through time. Any way, I wanted to say that really you are right, I just didn't look at it the right way- my bad.

ez2b12
ez2b12
13 years ago

@ sarp kaya

I don't think you are right on this one, not to be arguementative. But mutation is a sudden change in genes not a accumulated change that occurrs slowly. What you describe is simply the meachanism that makes us have very small differences that are really inconsequestial to the species as a whole, like having blue verses brown eyes. Here is a more detailed explanation of mutation.

Mutations are divided into three major types.
Gene mutation is the sudden changes of the DNA sequence. Gene being the unit for heredity. Therefore, gene mutation occurs in the DNA -- the Arginine,Thymine, Guanine and Cytosine nitrogenous bases.
An example of gene mutation is the point mutation.
Point mutation occurs due to the substitution of one nucleotide base pair with another. It may become a missense mutation where a nucleotide base pair is incorrect however it still forms the required amino acid.
Besides missense mutation, nonsense mutation could also occur due to point mutation. Instead of forming the correct codon, it forms the stop codon instead, resulting in the formation of smaller or shorter polypeptides.
Another type of gene mutation is the frameshift mutation.
The frameshift mutation occurs when a nucleotide base pair is deleted or a nucleotide base pair is inserted elsewhere in the chromosome, causing the whole chromosome to shift hence forming the incorrect polypeptides.

Now this does not gives us the reason that these mutations occurr, as far as I know no one has determined that yet. But it does describe them as sudden changes in DNA, not the accumulated changes that preserve our physical diversity. If these types of sudden mutations did not occurr we would never develope another species. The differences you are explaining just do not add up to a real change in our structure, only variations in hair color, body shape (like tall and thin versus my unfortunate build short and thick) eye color, etc., etc.

mvairavan
mvairavan
13 years ago

@prix

On my way to "Judgment Day – Intelligent Design on Trial: Nova".
But i've to say, i have the least biology background.. I am from pure computer background... :)

sarp kaya
sarp kaya
13 years ago

sorry, I meant "parents to offspring" not "siblings".

sarp kaya
sarp kaya
13 years ago

mutations happen because dna is copied each time a living thing is conceived through reproduction. the process of copying is never perfect. very minor changes (mutations) occur each time dna is copied from parents to siblings. these changes multiply over great lengths of time. if they result in changes that benefit the organism in some way, they give that organism an "edge" over its competitors that will, in most cases, allow that organism to live longer and reproduce more than its competitors. the "edge" is therefore passed on to subsequent generations more frequently, spreading over an increasingly wider section of the population with time. those individuals without the "edge" fair poorer and thus reproduce less. in time they disappear altogeher. in short : survival of the fittest and the best.

Prix
Prix
13 years ago

@mvairavan

haha, no I wouldn't call it stupid just that it leads nowhere except back to the questions without any answer. We all have you respect other peoples views at the same time as questioning them.

Btw have you watched other evolution documentaries on this page? You can ask people here and they'll recommends pretty good documentaries that can answer your questions or even raise more questions. I would recommend "Judgment Day - Intelligent Design on Trial: Nova". There is one problem with it, they KIND OF seem like they're pushing a propaganda on you. But it's not like that, they're just explaining things in details.

mvairavan
mvairavan
13 years ago

@ez2b12

"In other words the concept is beautiful, but the execution is horrible."

Yes - That sum's it up all!!!, But i've started admiring the biological execution (mutation).

@Prix

I agree. Saying there is some power behind it and leaving the topic is a stupidity. If everyone had believed on God simply then science wouldn't have grown this far. I take my word back, lets dig deep to find out for real.

Thanks guys for all your kind explanations!!

Prix
Prix
13 years ago

@mvairavan

How that EXACT mutation happens? I don't know. But I do know is that mutations occur each time someone is born. No one is the same because of this. There are couple of documentaries explaining how the mutations happen but not why they occur.

Also, yes you may believe that there is a power behind it all. But that's not going to give any one else including yourself any answers.

Through out history people that didn't understand something simply implied it was God who did it. To presume something without any firm evidence is not acceptable in science. Many of us dislike to give this as an answer "I don't know", just because we want to show to others that we have knowledge that they don't.
There is no shame in accepting something that we don't know. If we don't know now then we will know it in the future.

But it's a great thing you ask questions. That's what moves us forward. Keep on asking questions, question everyone and their views, also question science. Without questions we cannot move forward.

jono
jono
13 years ago

@Randy ;)

ez2b12
ez2b12
13 years ago

@ Mvairavan

You may be right, that thier is some power beyond the God we have been told of or anything in nature we understand yet that causes these mutations. Myself, I do not believe that it is any intelligence that has some certain outcome it is trying to reach. If you follow the evolutionary history of life it is to sporatic and too many species simply do not make it for me to believe some intelligence has a goal in mind.

If it is some type of cosmic intelligence, that intelligence does not value the singular life of one creature at all. Evolution driven by natural selection is a horribly brutal and inhumane process that has not the slightest regard for the horror or physical pain of predation, starvation, desease, and of course ultimately death. It may in the end be the process that preserves biological diversity and a species survival, but it is not a process I would say a benevolent omnipotent intelligence should choose to utilize. In other words the concept is beautiful, but the execution is horrible.

mvairavan
mvairavan
13 years ago

@ez2b12:

Beauty!!! Thanks for your explanation.. Now i know that we dunno about the force behind it.. Not especially God, but i do believe that there's some power beyond all these to create such wonders...

Randy
Randy
13 years ago

HAHAHA! %Jono! Did you see what he did back there?

He called me a girl! Very clever with his emasculation of me!

The thing is, boys and girls all taste the same to me... darling...

(Seriously though, excellent come back! You are sharp as a tack!)

ez2b12
ez2b12
13 years ago

@ mvairavan

I do not think anyone knows why DNA mutates from one generation to the next, we simply know that it does. I have heard the hypothesis that it is caused by cosmic radiation, by some natural mechanism hidden within the DNA itself, and that some omnipotent all seing power, i.e. god, somehow manipulates DNA (laughable in my opinion) But no one has ever claimed to actually know for sure what causes it. For another point of view on this very topic you should check out Homofuturus, a doc right here on TDF.

All we know is that it is not a choice we make or that some other power makes for us, which is why I find the whole "God did it" thing laughable. If God did it then every mutation would be the correct one for the survival of the organism mutating, right? Surely he wouldn't be like, "O.k. I'll make this one white and have a little fun before I change it to black, the actuall color that will help save them from predators." Most mutations result in the death of the organism that inherits it, in fact most are hiddeous and have no concievable practical use at all. Besides any omnipotent being would have been able to get it right the first time, not come back later and be like, "Oh yeah, I guess I should have made the rat black instead of tie-dye he does kind of stand out doesn't he."

I think this documentary was trying to say that we now understand the mechanism by which these mutations are past on and able to be seen directly- DNA. In Darwin's time they had no idea what the natural mechanism for inheriting your parents features was, or where they could find the enternal mechanism that stored this information and therefore must be changed in order for a mutation to appear. Being able to examine DNA gives us an enormouse advantage when it comes to studying, understanding, and proving evolution. Here is an arguement about the number of paired chromosomes in humans versus that of apes that is only supportable by use of DNA comparrison.

Humans have 23 pairs of chromosomes as opposed to apes having 24. This means one of two things must have occurred- either a fusion of two separate chromosomes occurred in the human line, or a fission of a chromosome occurred among the apes. The evidence favors a fusion event in the human line. One could imagine that the fusion is only an apparent artifact of the work of nature (due to common ancestry). The common ancestry scenario presents two predictions. Since the chromosomes were apparently joined end to end, and the ends of chromosomes (called the telomere ) have a distinctive structure from the rest of the chromosome, there may be evidence of this structure in the middle of human chromosome 2 where the fusion apparently occurred. Also, since both of the chromosomes that hypothetically were fused had a centromere (the distinctive central part of the chromosome), we should see some evidence of two centromeres. And of course we do see these exact things when we study human DNA versus ape.

Now creationist would have us believe this to be evidence of a common designer and nothing more. But if that is the case why do we see these telomere structures in the center that are always at the ends of chromosomes, why do we see two centromere regions out toward the ends when there is always just one in the center of other chromosomes? Was god not capable of originality? Did he see the need for humans and say, "o.k just take these two chromosomes and jamm them together as such, now twist and pinch and viola- a human" If he did do this why does the bible describe it so differently and more simply, he just formed a dirt doll and blew in the nostrils in the bible. This is just one example of what we know now thanks to DNA that we didn't know when Darwin presented his theory of evolution.

Its also another good example of how religiouse people tend to change thier views of the nuts and bolts of creation as science disovers more and more facts. The result being that through out the years God has become more and more impotent instead of omnipotent. Soon the hard liners will be the deists not the fundementalists, and eventually they will also cease to be. One by one we will make the religee sacrifice his magic for fact, and there will be no trade backs.

mvairavan
mvairavan
13 years ago

@prix:

"If a mutation is suitable for a species to survive then they do so. If it isn’t then they don’t."

How that (exact) mutation happens, thats my question...

@Jono:
Sorry if i am not as smart as u, but i am not here to argue..

jono
jono
13 years ago

@ Randy

Nope I have this effect on all the girls

Randy
Randy
13 years ago

@Jono

You and I have argued, even as we agree on almost everything.

But, I am looking at your enormous brain...

I gotta say... I want to eat it!

Is that wrong?

jono
jono
13 years ago

@canex

Refresh, if that doesnt work update your flash player.

jono
jono
13 years ago

@mvairavan

Did you even watch the doc or read the replies to your question?

If you aren't being obtuse then you prbably need to watch a simpler documentary on the basics of evolution.

canex
canex
13 years ago

i am not seeing any video or link ???

Shashikiran Srinivasa
Shashikiran Srinivasa
13 years ago

Exceptional, mind-blowing, amazing.. Add all other adjectives to this list. One of the finest documentaries made. I knew some of it and was educated in many others. I always try to teach evolution to creationists, this is the reason why I will do more. I have new material to talk about next time! All thanks to Darwin and other followers of him.

Prix
Prix
13 years ago

@mvairavan

I don't know a lot of biology but it just seems like with the comment of-

"If i feel a need for a tough skin to live in antartic will my heredity automatically mutate to get one?? Need to explain how those switches decide to on and off themselve"

Just makes you seem like you're way off. Nothing turns on or off, even if you have a NEED for something it doesn't mean you'll have it.

It's not like the rocket rat wanted the change or needed it. Needing it for survival yes, but needing it for other things THAN survival? I don't think so, maybe there might be another explanation. But as far as I can see, no.

Perfect mutation? No no no no...no...there is no such things as perfect mutation. There is nothing that is perfect.

The pocket rat didn't match the color EXACTLY. It wasn't perfect, not even close to GOOD. Instead of being all that it was suitable for its survival. The information i've gather is that mutations aren't good or bad. Those are just words we use to describe something, in nature nothing is good or bad. It's just nature being nature. If a mutation is suitable for a species to survive then they do so. If it isn't then they don't. Adapt or be overthrown by superior species.

And the force behind all of this...I wouldn't touch that with a 10 foot clown-pole.