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Author Topic: Why have chimps changed so little since diverging from humans?  (Read 24665 times)

Offline Grant Silver

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I am ignorant about evolution, but the theory says humans separated from the ape some 6 million years ago slowly became upright hominids until they evolved into modern man

My questions is if we look at the chimpanzee he seems to have remained static for millions of years

Is this correct?

Grant
« Last Edit: 03/10/2008 22:45:13 by chris »


 

Offline Asyncritus

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Grant

There's no way that a chimp could become a human. The physical and psychological gaps are far too great.
 

Offline atrox

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Is this correct?

No, itīs not.
The theorie says, they separated from apes...not from chimpanzees.
The oldest hint on chimpanzees is about 500.000 years old, but itīs not clear yet, if these fossils are from modern chimpanzees or from some other kind of chimpanzee.
 

Offline atrox

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Grant

There's no way that a chimp could become a human. The physical and psychological gaps are far too great.

The physical and psychological gaps between a babygirl and an old woman are also enormous...  ::)
 

Offline Grant Silver

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Hey Guys

My point is that man evolved from a primitive hominid, the chimp must also have evolved from more primitive ancestor. Is there any evidence for this?

Grant
 

Offline BenV

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I'm not quite sure what you're asking.  Genetic evidence shows that we share an ancestor with chimps, so yes, chimps have evolved from that ancestor, just as we have.

As Atrox explained, we didn't evolve from chimps, we evolved from the same stock as chimps.  They adapted to a forest environment, while we adapted to a different environment (various theories suggest open plains, edge of forest or water boundaries).

If the selection pressures of their environment haven't changed much, then they wouldn't have changed much either (physically - immunologically it's a different story - they're likely to have evolved to face new pathogens along the way).
 

Offline Don_1

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What you must remember is that animals evolve according to their environment. Life in the forest would mean the ability to climb and move around in the trees would be paramount in the evolution of animals in such circumstances, while life on the edge of forests would not have such a great need for this ability.

The Chimp is well adapted to it's environment and has been for a long time. Man, on the other hand, had to go through a number of stages to become properly adapted to life split between forest and plains.

Our ancestors were not very good on the plains, almost any 4 legged animal could out run them and was more stable. While in the trees the monkey's and apes were far superior.

Man became non-specialised and as such could move from one environment to the other with ease. This was a great advantage over those tied to one or the other. If we do share a common ape ancestor, then when we split, man took one path and the chimp another.

The chimp's ancestor was probably already close to perfection for it's path, but man's had a long way to go from tree dwelling ape to multi habitat homo erectus.

Evolutionary change only needs to happen if there is a need for it. Sharks reached perfection a long time ago and therefore have not needed to evolve further. Each species of Shark is well adapted to it's particular requirements. To take this even further, the Crocodilians and Tortoises reached their peak of perfection over a 100 million years ago, so they have had no need to evolve further. Antelope need to continue to evolve in order to be able to avoid becoming a Lions dinner, while Lions must continue to evolve if they are to catch the Antelope. Evolution continues to this day.
 

blakestyger

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Simply and briefly, this is what happened to form the diversification of the primate groups. The figures are in (very much) rounded 'millions of years ago'.

At around 50 mya the single common ancestor line split into the Prosimians (modern day representative, the tarsiers), the New World Monkeys (today's spider monkey) and a third carried on until it split around 35 mya to form the Old World Monkeys (today's colobus monkey) and the Hominoids.

The Hominoid line split about 15 mya into the baboons and another line that carried on until about 7 mya when it branched to form the orangutans and a second branch that finally split into three lines at about 6 mya that became the gorillas, chimpanzees and humans (the genus Homo).

A lot of this branching was driven by the movements of the major land masses forming land bridges that increased the range of creatures and the likelihood of speciation.

So, in a nutshell the chimpanzee/gorilla/human common ancestor dates from around 6mya.
 

Offline Asyncritus

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You guys ever seen a list of the differences between an anthropoid and a human? Show how they could possibly evolve from a 'common ancestor'.

Man is the only creature with the ability to count extensively
Man is the only creature with the ability to have a religion
Man is the only creature with the ability to have a moral sense
Man is the only creature with the ability to appreciate beauty
Man is the only creature with the ability to have a complex language
Man is the only creature with the ability to bury its dead
Man is the only creature with the ability to reason abstractly
Man is the only creature with the ability to manufacture tools and weapons
Man is the only creature with the ability to make articles of dress and adornment
Man is the only creature with the ability to make fire
Man is the only creature with the ability to sow and reap
Man is the only creature with the ability to improve its appearance
Man is the only creature with the delicacy and precision of touch that enables eye surgery as an example

2 A quadrupedal animal cannot be converted into a bipedal one for the following excellent reasons:

The shape of the pelvis is entirely different. In man it is broad, low, and basin-shaped.
In the apes, for example, its broad axis is from back to front
In man, its width from one iliac crest to the other is greater than its height. In
apes, it is the other way round.
The pubic symphysis is short in man, long in apes.
In man the lower part of the pelvis is almost equally distributed in front of and behind the socket bone. In apes it is inserted much further back, to permit the forward bending posture.

The special features of the human pelvis appear early in embryonic development , and are not preceded by conditions even resembling those that prevail in apes.
The large ilia, broad pelvis and well-developed spines all serve to give us our erect posture.

3 The coccyx is longer in human beings than in anthropoid apes (4 fused in humans, 3 fused in apes).
The human coccyx is placed lower than in the ape. It reaches almost to the end of the pubic symphysis, involving the production of a transverse perineum, as opposed to the oblique one of the ape.
The absence of a tail in man is due to the impedance it would offer to movement in an upright posture.

4 The straight legs of man are unique to man. Those of the anthropoids cannot be straightened.

5 Man is the only fully plantigrade primate.

The foot presses on the ground at three points which form the pillars of a double arch.

In the anthropoids, only the outer edge of the foot presses on the ground when the animal is standing.

In the apes, the relative lengths of the fingers are similar to those of the toes.

The first toe of the ape is opposable to the others. Those four are bound together by a broad band of fibre known as the transverse metatarsal ligament. In man, this ligament includes the big toe, and so binds all 5 toes together.

6 In the spinal column, there are other unique features.

The axis vertebra is absolutely vertical in man. In the apes it is oblique.

In order that that the head may rest on the spine in the vertical axis, the spinal column is curved to the front in the neck region, then it curves backwards and then forward in the lumbar region. This last curve is exhibited by no other animal.

7 The human arm differs markedly from that of any anthropoid.
It alone can be stretched so that upper and lower arm form a straight line.
The arm is relatively much shorter than that of any anthropoid, and the ratio of the length of the upper to the forearm is lower.
The human arm hangs differently from that of any anthropoid: the thumb points forward. In the apes, it points inward.

8 Man’s thumb is perfectly opposed to the rest of the fingers and is much bigger than that of the apes. The transverse lines on the palms run obliquely, rather than transversely as in the apes.

9 The scapula is applied to the back of the thorax in man. In other animals it is applied to the side of the thorax.
The socket for the insertion of the humerus faces outwards in man. In the apes, it faces downwards.

10 Man is unique among land animals in not possessing a covering of hair or fur. As a result, unlike other animal, has to adopt clothing of one sort or another to retain heat and ward off cold.

The absence of hair is difficult to explain – because the young anthropoid clings to the hair of its mother like a leech. The mother therefore need not bother too much about the infant when she is moving about. There is not the faintest resemblance to this in the human species.

11 Among other features exhibited by man and not the anthropoids are the following:
the bed of fat beneath the skin, the legs being longer than the arms, the large size and permanent separation of the nasal bones in man, the shortness of the external ear, the human brachial artery lying below the median nerve, the lack of sexual differentiation in the teeth, the premolar teeth of man having fewer roots than the anthropoids.

Whole theses have been written on the similarity of the features of the crowns of the teeth. But there is a most significant fact which is conveniently ignored. The premolar teeth of man have usually only one root, though sometimes the first upper pre molar is double rooted. In the anthropoids and monkeys each upper premolar has 3 roots and each lower two roots.

11 The brain size of a man is, relative to the size of the body, smaller than that of the tarsier monkey. Therefore, size alone is incapable of explaining the psychological gulf outlined in Section 1 above.

12 Sexual female anatomy is also different. In other animals, the vagina is parallel to the abdomen. In the human female it is tilted backwards because of the upright posture. You may wish to comment on the question as to whether the upright posture created the angling of the vagina, or whether the angling created the upright posture. Or whether it was created that way.

The foregoing shows that there is nothing to indicate human common descent from a common ancestor of any description.
« Last Edit: 02/10/2008 19:20:56 by Asyncritus »
 

Offline Don_1

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Yep, marvellous thing evolution eh!
 

Offline atrox

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Yep, marvellous thing evolution eh!

^^
 

blakestyger

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Asyncritus - you've missed one out. How about:

Man is the only creature with the ability to present vacuous arguments.
 

Offline BenV

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I'm sorry Asyncritus, you're saying that man is different from apes and so can't have evolved from the same stock?

That's a terrible arguement - the point is that we evolved from the same stock - so we, and they, have changed over time.  You seem to be saying that the only way man can have evolved from the same ancestor as chimps would be if we were chimps.

Furthermore, most of your comments (the list of "man is the only...") aren't even true.

Let's have a look at just a few of them, shall we?

Man is the only creature with the ability to count extensively - Extensively maybe, but even bees can count up to 4!
Man is the only creature with the ability to have a religion - This one is probably true

Man is the only creature with the ability to have a moral sense - We know that chimps act in a way analogous to guilt when they have done something that is selfish or bad for the troupe.

Man is the only creature with the ability to appreciate beauty - Are you joking? Many female birds will opt to mate with the most impressive looking male, and the same is true for countless other species

Man is the only creature with the ability to have a complex language - Again, not so.  We know that dolphins have complex communication, as to many monkeys (with different sounds for different types of food, or different threats).  Bees (again) can communicate with other bees to say where nectar can be found.

Man is the only creature with the ability to bury its dead - Maybe, but how is this relevent?

Man is the only creature with the ability to reason abstractly - Scrub Jays have been shown to use some extent of abstract reasoning.

Man is the only creature with the ability to manufacture tools and weapons - Chimps again.

Man is the only creature with the ability to make articles of dress and adornment - Possibly, but magpies collect shiney things to adorn their nests, Birds of paradise clean up the ground before performing a mating 'dance'

Man is the only creature with the ability to make fire - Fair enough, and almost certainly the only animal with a requirement to do so.

Man is the only creature with the ability to sow and reap - Ants cultivate fungi.

Man is the only creature with the ability to improve its appearance - Birds preen, chimps groom etc.  But this may just be to keep clean.  Again, if animals have no need to do so, they wouldn't have evolved to do so.

Man is the only creature with the delicacy and precision of touch that enables eye surgery as an example - Yup, we've evolved to be pretty dextrous.  But a hummingbird can, mid flight, hover and insert a long, thin beak into a plant to drink nectar, and there are plenty more exampes of delicate precision in nature.

Quote
The foregoing shows that there is nothing to indicate human common descent from a common ancestor of any description.
You really believe that, don't you? Even though it's completely wrong? All of the things you listed are genetically controlled, and we know that genes are passed on to the next generation, with the most advantageous more likely to be represented in this generation - so the genes of a population change over time.  All of these things are evidence for how we have evolved from a common ancestor with the other great apes.
 

Offline Don_1

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You beat me to it BenV.

This 'man only' list is mostly wrong.



Religion - Serves no practical purpose and has resulted in the death and persecution of millions.

Burial - So we can be eaten by scavengers underground instead of above. No real purpose.

Tools - Birds cut and strip twigs to get grubs out of trees and use stones as bombs. Sea Otters use stones to break open shells.

Adornment - Who needs it when you're Peacock, Bird of Paradise, Red Admiral, Chameleon???

Fire - We still can't always control it. Animals are cleaver, they don't play with it.

Improve appearance - Many animals have developed appearance enhancers that can be utilised on demand, from Fire Fies to Cobra's and lizards, birds and apes.

Delicacy - Ever seen the bone crushing jaws of a crocodile gently pick up it's young or a caymen break open an egg to set a hatchling free? The dexterity of the Hummingbird Hawk Moth.

On the odd occasion where it is right, it is, as you say BenV, a question of the requirement of the different species. All of these skeletal differences between man and apes can and would change given the time and necessity. Some chimps, in the right habitat, have been observed walking upright. Perhaps given the time, these chimps will become an entirely different species to their tree dwelling cousins.
 

Offline atrox

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btw. even if these lists were mostly right (as they are not, as Ben and Don showed), that wouldnīt tell us anything either.
Evolution doesnīt mean, that there is no room for special species with pretty special abilities... why would you even believe, that the theorie of evolution couldnīt blend well with that?
If we follow your arguments it would be impossible for a newborn baby to become an adult...because a newborn doesnt share any of these abilites with adult human either ::)
 

Offline RD

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Adornment - Who needs it when you're Peacock, Bird of Paradise, Red Admiral, Chameleon???
The Bower bird does add adornment to its nest-like constructions: (a bit like an artists "installation").


Fire - We still can't always control it. Animals are cleaver, they don't play with it.
Given anthropogenic global warming, then maybe starting fires wasn't a good idea.  :)

 

Offline Asyncritus

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Why have chimps changed so little since diverging from humans?
« Reply #16 on: 04/10/2008 09:34:41 »
Asyncritus - you've missed one out. How about:

Man is the only creature with the ability to present vacuous arguments.

Yeah, and you're a prime example of that aren't you? ;D
 

Offline Asyncritus

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Why have chimps changed so little since diverging from humans?
« Reply #17 on: 04/10/2008 11:13:09 »
Quote
I'm sorry Asyncritus, you're saying that man is different from apes and so can't have evolved from the same stock?;/quote]

Absolutely. The difference is both quantitative and qualitative. And inexplicable.

Quote

That's a terrible arguement - the point is that we evolved from the same stock - so we, and they, have changed over time.  You seem to be saying that the only way man can have evolved from the same ancestor as chimps would be if we were chimps.

Look, if we 'evolved from a common stock' then that common stock was more primitive and dumb than either us or chimps, right? Right.

Q. How did Dumbo Ancestor become either chimp or us? When we know that mutations don't work, and acquired characteristics can't be inherited!

Quote
Furthermore, most of your comments (the list of "man is the only...") aren't even true.

Let's have a look at just a few of them, shall we?

Man is the only creature with the ability to count extensively - Extensively maybe, but even bees can count up to 4!

Fantastic! And yeah, they can construct hexagonal honeycombs too! How did they evolve that we wonders, yessss, we wonders. So a bee is comparable in counting ability to a human! Try teaching them calculus some time.

Quote
Man is the only creature with the ability to have a religion - This one is probably true

Quote

Man is the only creature with the ability to have a moral sense - We know that chimps act in a way analogous to guilt when they have done something that is selfish or bad for the troupe.

Oh yeah. They have written laws, ethics, morality too!

Quote

Man is the only creature with the ability to appreciate beauty - Are you joking? Many female birds will opt to mate with the most impressive looking male, and the same is true for countless other species

Erm, and paint pictures, admire the view, take pics, write poetry...

Quote


Man is the only creature with the ability to have a complex language - Again, not so.  We know that dolphins have complex communication, as to many monkeys (with different sounds for different types of food, or different threats).  Bees (again) can communicate with other bees to say where nectar can be found.

We aren't discussing instinct. We're talking about language as we know it, being constructed and used as we use it. Your argument is looking quite silly now.

Quote

Man is the only creature with the ability to bury its dead - Maybe, but how is this relevent?

It is unique. Not evolved.

Quote

Man is the only creature with the ability to reason abstractly - Scrub Jays have been shown to use some extent of abstract reasoning.

Ho ho ho! Was he Albert Jay Einstein?

Quote

Man is the only creature with the ability to manufacture tools and weapons - Chimps again.

So we have Atomic Chimp now, do we?

Quote

Man is the only creature with the ability to make articles of dress and adornment - Possibly, but magpies collect shiney things to adorn their nests, Birds of paradise clean up the ground before performing a mating 'dance'

Groannnnn!

Quote
Man is the only creature with the ability to make fire - Fair enough, and almost certainly the only animal with a requirement to do so.

No selection advantage/requirement. Just unevolved.

Quote
Man is the only creature with the ability to sow and reap - Ants cultivate fungi.

Excellent point. Where did they get that from?

Quote
Man is the only creature with the ability to improve its appearance - Birds preen, chimps groom etc.  But this may just be to keep clean.  Again, if animals have no need to do so, they wouldn't have evolved to do so.


Chimps with lipstick, hair gel, razor blades...Hmmm.

Quote
Man is the only creature with the delicacy and precision of touch that enables eye surgery as an example - Yup, we've evolved to be pretty dextrous.  But a hummingbird can, mid flight, hover and insert a long, thin beak into a plant to drink nectar, and there are plenty more exampes of delicate precision in nature.


Yeah, and perform eye surgery and give enemas too!

Quote
The foregoing shows that there is nothing to indicate human common descent from a common ancestor of any description.

You really believe that, don't you? Even though it's completely wrong? All of the things you listed are genetically controlled, and we know that genes are passed on to the next generation, with the most advantageous more likely to be represented in this generation - so the genes of a population change over time.  All of these things are evidence for how we have evolved from a common ancestor with the other great apes.
 

Yeah, of course. And where did the genes which are passed on to the next generation come from?

Now about those physical characteristics. Have a go at them.
« Last Edit: 04/10/2008 11:55:09 by Asyncritus »
 

Offline BenV

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Why have chimps changed so little since diverging from humans?
« Reply #18 on: 07/10/2008 11:06:18 »
Fair enough, I give up.  There is clearly no chance that you are going to listen to sense, look at the vast amount of evidence and accept that evolution through natural selection is how species change and diverge over time.  Your pre-conceived notion that all life on earth was created by your imaginary friend is too strong, and has blinded you to logic, sense and science.  You will, therefore, forever believe fairytales over the truth, and I'm sorry that I couldn't help you.
 

Offline Asyncritus

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Why have chimps changed so little since diverging from humans?
« Reply #19 on: 08/10/2008 09:52:12 »
Quote
Fair enough, I give up.  There is clearly no chance that you are going to listen to sense, look at the vast amount of evidence and accept that evolution through natural selection is how species change and diverge over time.  Your pre-conceived notion that all life on earth was created by your imaginary friend is too strong, and has blinded you to logic, sense and science.  You will, therefore, forever believe fairytales over the truth, and I'm sorry that I couldn't help you.

Thanks for your valiant attempt, anyway Ben.
 

Offline Bored chemist

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Why have chimps changed so little since diverging from humans?
« Reply #20 on: 08/10/2008 20:08:17 »
To a greater or lesser extent all those "points" just mean that we (uniquely) have a big complex brain.
It's no more difficult to see how a big brain can evolve than a long neck as per the giraffe.
 

In the meantime rather than writing "The foregoing shows that there is nothing to indicate human common descent from a common ancestor of any description." perhaps you can come up with an alternative explanation for the fact that we share nearly all our DNA with chimps and about half with bananas.
 

Offline Asyncritus

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Why have chimps changed so little since diverging from humans?
« Reply #21 on: 08/10/2008 23:21:43 »
Quote
To a greater or lesser extent all those "points" just mean that we (uniquely) have a big complex brain.
It's no more difficult to see how a big brain can evolve than a long neck as per the giraffe.

The fact is, we don't. From the POV of sheer quantity, the sperm whale beats us out of sight (7-8 kg brain). From the POV of ratios the shrew ECQ beats us out of sight. 

It isn't quantity - it's something else. But what? My answer is that we are made in the image and likeness of God who endowed us with a lot more than gray matter.
Quote
In the meantime rather than writing "The foregoing shows that there is nothing to indicate human common descent from a common ancestor of any description." perhaps you can come up with an alternative explanation for the fact that we share nearly all our DNA with chimps and about half with bananas.

Well, if the chimps eat bananas...

But seriously, I don't quite know what genetic similarities mean. Resemblances are tricky things, and insisting that a close similarity means common descent of some sort, is at best dubious.

Here are 2 examples of what I mean. I ask you, are they descended from a common ancestor?
 

Is that related to a plant or not?

Are these related, or not:


You also have the fact that in chimps, there are 2 EXTRA CHROMOSOMES. Now if common ancestor A had 44 chromosomes, then at some point 44 became 46 (us) and 48(chimps etc).

There is the ugly fact that 1 extra human chromosome creates Downs syndrome. Anything else will produce destruction and death.

So common ancestor becoming human or chimp couldn't happen.

Now add to that all of the other 20 or so physical differences I listed above, then you really have some serious problems with evolution and common descent.
« Last Edit: 08/10/2008 23:25:28 by Asyncritus »
 

Offline Bored chemist

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Why have chimps changed so little since diverging from humans?
« Reply #22 on: 09/10/2008 07:01:23 »
So, you didn't see the word "complex" in my post or did you just ignore it?

The examples you give are all related, some more closely than others.
Physical similarity isn't a reliable guide to kinship (though it's often quite good). That's exactly why taxonomists generally rely on DNA evidence these days.

I think your most telling statement is "But seriously, I don't quite know what genetic similarities mean."
Perhaps you should find out about the science before asserting it's wrong.

I take it that you are also unaware that modern wheat has 3 times as many chromosomes as it's ancestors and does really rather well.
« Last Edit: 09/10/2008 19:43:38 by Bored chemist »
 

Offline Asyncritus

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Why have chimps changed so little since diverging from humans?
« Reply #23 on: 13/10/2008 08:11:22 »
So, you didn't see the word "complex" in my post or did you just ignore it?

The examples you give are all related, some more closely than others.

You're not serious? The top picture is of an INSECT closely /identically resembling a LEAF. It is mimicking a leaf, closely resembling it - but does that prove that they are closely related? Don't be silly.

The butterflies below are mimicking one another, and the resemblance is quite startling - but does that prove relationship? You gotta be kidding.

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Physical similarity isn't a reliable guide to kinship (though it's often quite good). That's exactly why taxonomists generally rely on DNA evidence these days.

The fact of the matter is that the DNA and protein sequencing evidence shows that the morphological similarities are exactly borne out by the morphological evidence.

Thus we would expect close similarity between chimps and us at genetic level. The morphologists have been saying so ever since Linnaeus' time. So there's nothing new there.

But as the evidence above shows, close similarity at morphological or genetic level is no assurance of relationship or common descent. They are both subject to alternative explanations. There are common DNA 'features', but that does not prove common 'descent'.

We know that DNA sequencing identifies parenthood - and that is 99.9% correct. But to extend that to a common ancestor 3.5 BILLION years ago (the cyanobacteria)is the height of stupidity as far as I am concerned. If that is not extrapolation on a gigantic, monstrous scale,I don't know what is.

DNA sequencing works well WITHIN SPECIES - but to go beyond that is not safe, or even reasonable.

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I take it that you are also unaware that modern wheat has 3 times as many chromosomes as it's ancestors and does really rather well.

You're referring to the phenomenon of polyploidy which is common in plants. You will note that no new genus or family has been formed, but these are variants on a theme.

Polyploidy does not occur in mammals as a rule, in fact I think it was only recently that a polyploid rat was found.But it was a polyploid RAT - it hadn't changed into a shrew or something else - just as a Downs syndrome person is a human being, not some other species.

And there's your problem in a nutshell. A chimp has 2 extra pairs of chromosomes, and is perfectly normal.

So if we start with common ancestor X, with 44 chromosomes, then for that to evolve into a human with 46, and a chimp with 48 would result in disaster. You note that 46 and 48 are NOT polyploids of the original 44.

And on that matter, did you know that the domestic cat and the domestic pig have exactly the same number of chromosomes (38)? And that a gorilla, a chimpanzee and the potato plant and the tobacco plant all have 48 chromosomes? Does that prove that they are related?

Or that the whole idea of common descent is particularly stupid?
« Last Edit: 13/10/2008 08:15:46 by Asyncritus »
 

Offline Asyncritus

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Why have chimps changed so little since diverging from humans?
« Reply #24 on: 13/10/2008 08:17:03 »
I haven't mentioned the complexity of the human brain, because you really don't want to go there when discussing the chance production of new species. Trust me, you don't, but if you insist, I will.
 

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Why have chimps changed so little since diverging from humans?
« Reply #24 on: 13/10/2008 08:17:03 »

 

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