What exactly is "Natural Selection"?

[The Last Conformist]

It may come as a shock as well, but the notion that creatures change over time was a suspicious from the naturalists long prior to darwin, and the relevant inovation of the "The Origin of the Species" was exactly to offer a natural theory to explain this which was implied from the collected data, basically removing the need for divine intervention.

So, not many shocking news there...

The notion of fixity of species, as far as Western science is concerned, began with Linnaeus. He later backed away from the idea, but, as we see, it has taken a deep hold in certain other circles.

 

[Scuffer]

Is this what Evolution is about? Natural selction seems to be a losing of genetic material rather than gaing of infomation.

The amount of genetic infomation has absoltely nothing to do with evolution. Evolution isn't about the creation of abilites, it is the fitting into niches more snugly. As with that shrimp, the removal of extraneous features is as valuable method of evolution as the gaining of new ones. The amount of actual DNA is totally unrelated to complexity of the organism.

 

[Little Raven]

If you take a shrimp, make it evolve during 100000 years, what do you think will happen? First, it will grow some kind of extra flipper on a mutation or something. Then some other mutation will give it an extra eye, then... then.. then... untill it cant be called a shrimp anymore.....

What you get will depend on how you 'make it evolve.'

If an animal is already perfectly suited to it's habitat and lifestyle, then 10 million years isn't going to change it. Look at scorpions. They've been around for hundreds of millions of years, and they're basically unchanged. That's because there's no need for them to change...they're pretty much perfect the way they are.

 

[Sophie 378]

@Scuffer: Yup... I shall just check my 1st-year biochemistry folder: there are nematodes that have bigger genomes than humans iirc. Will give details in an edit in a few mins.

OK, found the piccie I remember. Source: Mathews, Van Holde and Ahern, Fig 28.1 pg 1069. This is a written summary of a reprinted diagram from a book, so don't take it as 100% accurate - but main points stand. Will also see if I can find an online picture of the graph.

Organisms with bigger genomes than humans:
- Some reptiles
- Most amphibians
- Some bony fish
- All cartilaginous fish, eg sharks
- Some molluscs
- Some insects
- Most plants!

 

[classical_hero]

Hox duplication.

Next time, know what you're talking about.

That actually does not add extra genetic material to the gene pool. All it does is give an extra body part, which is why some people are born with six fingers. But that is not something that the body does not have already. You still have not given me an example where mutation gives the species something that it previously did not have and that it contiunes wiht the gene pool. Hox duplication only stays with the one who has it and does not replicate itself and it is not adding anything to the gene pool because and extra finger is like saying that having one less finger is mutation. This proves nothing. An extra body part that Hox duplication gives is not adding to the gene pool.

 

[The Last Conformist]

What you get will depend on how you 'make it evolve.'

If an animal is already perfectly suited to it's habitat and lifestyle, then 10 million years isn't going to change it. Look at scorpions. They've been around for hundreds of millions of years, and they're basically unchanged. That's because there's no need for them to change...they're pretty much perfect the way they are.

Scorpions may have changed little in overall appearance, but I'm willing to be there's been alot of evolution at the genetic level.

 

[Scuffer]

@Scuffer: Yup... I shall just check my 1st-year biochemistry folder

Mine went up in a blaze of glory when I graduated. Man, I hated biochemistry! I think it's also known as the C-value paradox.

 

[Renata]

The amount of genetic infomation has absoltely nothing to do with evolution. Evolution isn't about the creation of abilites, it is the fitting into niches more snugly. As with that shrimp, the removal of extraneous features is as valuable method of evolution as the gaining of new ones. The amount of actual DNA is totally unrelated to complexity of the organism.

And indeed, the genes for the development of eyes could have been wrecked just as easily by the addition of genetic material as by its loss.

 

[classical_hero]

It may come as a shock as well, but the notion that creatures change over time was a suspicious from the naturalists long prior to darwin, and the relevant inovation of the "The Origin of the Species" was exactly to offer a natural theory to explain this which was implied from the collected data, basically removing the need for divine intervention.

So, not many shocking news there...

Well Darwin was quoting a creationists almost word for word and yet he claims that it is a result of evolution. Can you please explain why his major source was Creationist and yet not much is known about this guy?

 

[Renata]

That actually does not add extra genetic material to the gene pool. All it does is give an extra body part, which is why some people are born with six fingers. But that is not something that the body does not have already. You still have not given me an example where mutation gives the species something that it previously did not have and that it contiunes wiht the gene pool. Hox duplication only stays with the one who has it and does not replicate itself and it is not adding anything to the gene pool because and extra finger is like saying that having one less finger is mutation. This proves nothing. An extra body part that Hox duplication gives is not adding to the gene pool.

You have no idea at all what you're talking about. It's pointless to argue with you until you've read a basic biochemistry textbook.

For the record, hox duplication *is* extra genetic material, and it *does* get passed down to offspring.

 

[Sophie 378]

You still have not given me an example where mutation gives the species something that it previously did not have and that it contiunes wiht the gene pool.

Did you read my first post? Gene duplication and mutations lead to more new proteins without necessarily removing the original. Of course, if you define "new information" as the sudden appearance of wings on a bear or something, of course there is no evolutionary evidence for such things occuring. Do you want a list of all the proteins I've been studying that have arisen through gene duplication and mutations?

 

[The Last Conformist]

That actually does not add extra genetic material to the gene pool. All it does is give an extra body part, which is why some people are born with six fingers.

Reference? Hox duplication shouldn't be able to give you an extra finger ...

But that is not something that the body does not have already. You still have not given me an example where mutation gives the species something that it previously did not have and that it contiunes wiht the gene pool.

Standard example: antibiotic resistance in bacteria.

Hox duplication only stays with the one who has it and does not replicate itself and it is not adding anything to the gene pool because and extra finger is like saying that having one less finger is mutation.

Having one finger less (for genetic reasons) is a mutation, doofus.

And if the Hox-duplicated mutant is able to breed, the extra gene is carried along to the next generation.

This proves nothing. An extra body part that Hox duplication gives is not adding to the gene pool.

Extra Hox genes don't give extra body parts - it gives extra potential to differentiate existing ones.


I don't know of any experiments with duplicating Hox genes (altho knocking them out can give you funky stuff like flies in lieu of eyes), but there's plenty of critters with full extra sets of Hox genes thanks to polyploidy.

 

[Bill3000]

Can you please explain why his major source was Creationist and yet not much is known about this guy?

Not all scientists are remembered in the halls of history.

 

[Little Raven]

Scorpions may have changed little in overall appearance, but I'm willing to be there's been alot of evolution at the genetic level.

Point granted. While the exterior shape of the scorpion remains basically identical to his ancestors of 400 million years ago, I'm sure the modern version produces a host of different proteins and amino acids. After all, it's not like bacteria have been sitting still for 100 million years.

But that just underscores my point further. Animals only evolve in response to environmental pressure. Scorpions have never had a need for more legs, more claws, or a thicker shell. They're already a perfect killing machine. But they have had a need for updated defenses against microbes, and I'm sure they have developed them.

 

[FredLC]

Well Darwin was quoting a creationists almost word for word and yet he claims that it is a result of evolution. Can you please explain why his major source was Creationist and yet not much is known about this guy?

I haven't read Darwin's work, so obviously I don't know that a "major sorce" for him was a creationist... nevertheless, as I have no reason to doubt your word, I'll indulge.

Maybe he wanted hard data. Maybe some other naturalists had collected info on morphology that Darwin could use, regardless of the fact they reached very different conclusions from them. Maybe only Darwin is known today because, despite the fact that he had help from info collected by others, he was the one who have achieved amazing innovative results with it.

That would not be a first. I remember, from when I read a biograph on Keppler, that he relied heavly in observations from another astronomer - who believed that the earth was the center of the solar system and that the orbit of the planets was round (Kepler was a hardcore supporter of Copernicus, and the man who figured out the ellipytical (sp?) orbit of the planets, to those who don't know). And why? Because the fact that the other guy (sorry, forgot his name) has reached wrong conclusions from his observations didn't make him any less precise in his notes about planet positions in given days, and hence, didn't make the data he collected any less valuable.

I'm sure there are several other examples around the world if one cares to look after it.

Regards .

Edit: Spelling.

 

[ironduck]

The craziest thing about these funnies like Zany and Elrohir, and I suppose, Classical Hero (or do you have another archaic bible interpretation?) is that they actually believe that after the flood a certain amount of 'kinds' evolved into the 'species' we have today - and considering the 'kinds' that were on the ark that would imply massive evolution in a minimum amount of time (they're young earth creationists, after all) - in other words, evolution on steroids! And yet they deny evolution.

Well Darwin was quoting a creationists almost word for word and yet he claims that it is a result of evolution. Can you please explain why his major source was Creationist and yet not much is known about this guy?

As could be expected, you asked your first question about evolution, got relevant answers, and since you have no reply to them you start quoting people in the 1800s! Do you really think a biologist needs to know whether Darwin came up with the stuff or copied it over from his wife or neighbour? That's for historians to meddle with for crying out loud.

 

[The Last Conformist]

The astronomer FredLC is alluding to is Tycho Brahe, whose assistant Kepler was. Unlike the theorist Kepler, he was first and foremost an observational scientist, and his tabulations of stellar positions were the best produced in the pre-telescope era.

 

[classical_hero]

Actually, the term "evolution" has a meaning which is misleading to most folk. A better naming, IMHO, would be "theory of adaptation".

If you read the article written by William Blyth, you will see that Creationist believe that creatures adapt to their environment, otherwise they will die if they do not. That is common knowledge that if an animal does not adapt to it's surroundings. Every time I have seen an atricle that says that a certain group of people or animal "evolve" with this certain charateristic, I always come back and say that it has nothing to with evolutiion, but it is just that they are adapting to the environment. You can see evidence of that all around the world. We humans are the most adaptable creature on the planet. We are able to live in climates that are very hot. You live in on and So do I, and yet we have some people who live in cold climates, and yet both are still human, but both are living in different circumstances.

So why do creationists believe in Natural selection. We believe also in the Bible and the Bible talks about death. Death is the biggest case for natural selection, because of death that people are forced to survive. Death will come to us all and as a result. That is the ultimate punishment for our sins. Eventually Natural Selection will happen to all of us, because at one moment of time we will die. Death is an issue that Evolutionists can never fully eplain why it actually occurs. Death is the issue that really separates the two groups.

 

[The Last Conformist]

Death is an issue that Evolutionists can never fully eplain why it actually occurs.

Which sort of death are you speaking? Apoptosis? Trivial to explain from the evolutionary standpoint? Death by predation, starvation or disease? Don't make me laugh. Death by old age in sexually reproducing species? Easily explained. Something else?

 

[Scuffer]

Well Darwin was quoting a creationists almost word for word and yet he claims that it is a result of evolution. Can you please explain why his major source was Creationist and yet not much is known about this guy?

Clearly the work of the Illuminati

But whoever wrote it down first makes absolutely no difference to whether natural selection supports evolution or some muddle-headed religious fantasy.

It would seem to me that scientists are better informed about religious standpoints than visa-versa.