Register | Sign In


Understanding through Discussion


EvC Forum active members: 65 (9162 total)
6 online now:
Newest Member: popoi
Post Volume: Total: 915,815 Year: 3,072/9,624 Month: 917/1,588 Week: 100/223 Day: 11/17 Hour: 0/0


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   The phrase "Evolution is a fact"
Peepul
Member (Idle past 5017 days)
Posts: 206
Joined: 03-13-2009


Message 106 of 217 (515228)
07-16-2009 10:41 AM
Reply to: Message 105 by NosyNed
07-16-2009 10:40 AM


Re: macroevolution's definition
Nosyned, thanks for the clarification

This message is a reply to:
 Message 105 by NosyNed, posted 07-16-2009 10:40 AM NosyNed has not replied

  
Stagamancer
Member (Idle past 4915 days)
Posts: 174
From: Oregon
Joined: 12-28-2008


Message 107 of 217 (515240)
07-16-2009 2:21 PM
Reply to: Message 93 by boysherpa
07-13-2009 10:17 AM


Re: my observations
Evolution, being both "micro" and "macro", is ambiguous in definition. Therefore its testability is questionable.
Evolution is completely UNAMBIGUOUS in definition. Evolution is a change in allele frequencies within a population. This is highly testable. Micro and macro are not descriptions of two different types of evolution, they are categories that help define the scope of the set of questions that an evolutionary biologist focuses on. It's like the difference between physical and organic chemistry: they are both chemistry, they both exist simultaneously, and there is no real world separation between the two, but they involve different sets of questions that different scientists can ask. (though, as other people have pointed out, these terms have mostly fallen out of use in the biological community)
speciation (which is poorly defined)
Actually speciation is well defined. What is difficult to pin down is what exactly a species is, which is due to the variety of different sexual reproductive strategies, and the fact that most things in biology exist within a continuum and not strictly partitioned categories. But just because species are hard to define does not mean populations can't evolve, which is the whole argument anyway.
Edited by Stagamancer, : clarification

We have many intuitions in our life and the point is that many of these intuitions are wrong. The question is, are we going to test those intuitions?
-Dan Ariely

This message is a reply to:
 Message 93 by boysherpa, posted 07-13-2009 10:17 AM boysherpa has not replied

Replies to this message:
 Message 108 by Rahvin, posted 07-16-2009 2:39 PM Stagamancer has replied

  
Rahvin
Member
Posts: 4032
Joined: 07-01-2005
Member Rating: 9.2


Message 108 of 217 (515241)
07-16-2009 2:39 PM
Reply to: Message 107 by Stagamancer
07-16-2009 2:21 PM


Re: my observations
Actually speciation is well defined. What is difficult to pin down is what exactly a species is, which is due to the variety of different sexual reproductive strategies, and the fact that most things in biology exist within a continuum and not strictly partitioned categories. But just because species are hard to define does not mean populations can't evolve, which is the whole argument anyway.
I like to compare speciation to a color spectrum. You can arbitrarily look at two points on a rainbow and say "this is blue" and "this is red," but you'd be pretty hard pressed to draw a precise line dividing each color. So too with species. We can look and say "this is species x" and "this is species y," but the continuum of continual change in populations makes drawing a line at the exact moment when a new species has formed rather difficult.

This message is a reply to:
 Message 107 by Stagamancer, posted 07-16-2009 2:21 PM Stagamancer has replied

Replies to this message:
 Message 109 by Stagamancer, posted 07-16-2009 4:30 PM Rahvin has not replied

  
Stagamancer
Member (Idle past 4915 days)
Posts: 174
From: Oregon
Joined: 12-28-2008


Message 109 of 217 (515247)
07-16-2009 4:30 PM
Reply to: Message 108 by Rahvin
07-16-2009 2:39 PM


Re: my observations
We can look and say "this is species x" and "this is species y," but the continuum of continual change in populations makes drawing a line at the exact moment when a new species has formed rather difficult.
Indeed. Though I just wanted to reiterate that just because the actual point or line of speciation cannot be determined (or doesn't really exist) doesn't mean that speciation is poorly defined as boysherpa contends

We have many intuitions in our life and the point is that many of these intuitions are wrong. The question is, are we going to test those intuitions?
-Dan Ariely

This message is a reply to:
 Message 108 by Rahvin, posted 07-16-2009 2:39 PM Rahvin has not replied

  
crawler30
Junior Member (Idle past 4776 days)
Posts: 15
From: Florida
Joined: 07-23-2009


Message 110 of 217 (516192)
07-23-2009 11:50 PM
Reply to: Message 8 by Rrhain
11-01-2008 5:59 AM


I`m not sure I understand what you are saying. Evolution hapens on it`s own through natural processes (natural selection, climate, etc.) not by purposfully introducing something different into a population. Such as dog breeding, is that or is not intelligent design? By humans of course, but it has a specific purpose, to exploit the attributes of certain types from certain animals. But in what way have we acctually obsereved as scientists the effects of evolution without any outside influence. I mean technically, I understand the fact that if we take two animals and breed them the offspring would then most likely have attributes of both parents. But the fact remains that if you leave things to their own devices man has never noted any significant changes in a population over time. And if we had then natural selection would be thrown out the window because appearently it happens faster than, natural selection would allow for an entire population to change into a new spieces.

This message is a reply to:
 Message 8 by Rrhain, posted 11-01-2008 5:59 AM Rrhain has replied

Replies to this message:
 Message 111 by Dr Adequate, posted 07-24-2009 12:14 AM crawler30 has not replied
 Message 112 by Perdition, posted 07-24-2009 10:35 AM crawler30 has replied
 Message 118 by Rrhain, posted 07-25-2009 9:06 PM crawler30 has not replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 111 of 217 (516195)
07-24-2009 12:14 AM
Reply to: Message 110 by crawler30
07-23-2009 11:50 PM


I`m not sure I understand what you are saying. Evolution hapens on it`s own through natural processes (natural selection, climate, etc.) not by purposfully introducing something different into a population. Such as dog breeding, is that or is not intelligent design?
No, that's just artificial selection.
But in what way have we acctually obsereved as scientists the effects of evolution without any outside influence.
Many of the best-studied small-scale evolutionary events are of the evolution of resistance to toxins such as antibiotics and pesticides, which obviously we did not bring about deliberately.
But the fact remains that if you leave things to their own devices man has never noted any significant changes in a population over time.
This is not actually true.
And if we had then natural selection would be thrown out the window because appearently it happens faster than, natural selection would allow for an entire population to change into a new spieces.
This is not grammatical, which may explain why I have no idea what you mean by it.

This message is a reply to:
 Message 110 by crawler30, posted 07-23-2009 11:50 PM crawler30 has not replied

  
Perdition
Member (Idle past 3237 days)
Posts: 1593
From: Wisconsin
Joined: 05-15-2003


Message 112 of 217 (516250)
07-24-2009 10:35 AM
Reply to: Message 110 by crawler30
07-23-2009 11:50 PM


But in what way have we acctually obsereved as scientists the effects of evolution without any outside influence.
The driver of evolution, besides the mutations themselves, is the environment. That's the thing that actually "selects" which genes get passed on, so in effect, all evolution is partly outside influence.
Some examples we have seen is the development of lactose digesting ability in e. coli. There are also the famous nylon eating bacteria. They couldn't have existed before we developed Nylon, so they must be a relatively new species.
But the fact remains that if you leave things to their own devices man has never noted any significant changes in a population over time. And if we had then natural selection would be thrown out the window because appearently it happens faster than, natural selection would allow for an entire population to change into a new spieces.
A population evolves, and the limiting factor is generation length. For a species to evolve, a mutation needs to be passed on a number of times for it to spread. When we want to see evolution in action, then, we use species that reproduce quickly. Things like bacteria, fruit flies, etc, that can go from generation 1 to generation 100 in just a couple weeks.

This message is a reply to:
 Message 110 by crawler30, posted 07-23-2009 11:50 PM crawler30 has replied

Replies to this message:
 Message 113 by crawler30, posted 07-24-2009 11:06 AM Perdition has replied

  
crawler30
Junior Member (Idle past 4776 days)
Posts: 15
From: Florida
Joined: 07-23-2009


Message 113 of 217 (516260)
07-24-2009 11:06 AM
Reply to: Message 112 by Perdition
07-24-2009 10:35 AM


But see the point is that the mainstream Darwinian view of evolution says that life changes on accident, but how can you explain this when you point out the nylon eating bacteria? A new niche opened up for an organizm to fill, so it was filled by a bacteria whom never existed before. This would lead me to believe that it purposefully happened because there was a reason to have happened. For instance, what reason would this species have come into being, obviously they had enough food to survive as they were so why the new diet? Because it could? Maybe it was because for eveything on earth, nothing is ever wasted, even excriment has its role in life. And every niche gets filled appearently some very quickly as these bacteria have shown.
BTW I did not join this forum to ridicule others for their beliefs or be ridiculed, I am here to learn with an open mind. I personally believe in God, but I do not expect everyone else to.
Edited by crawler30, : grammar

This message is a reply to:
 Message 112 by Perdition, posted 07-24-2009 10:35 AM Perdition has replied

Replies to this message:
 Message 114 by Perdition, posted 07-24-2009 11:34 AM crawler30 has replied
 Message 117 by Dr Adequate, posted 07-25-2009 4:07 PM crawler30 has not replied
 Message 119 by Rrhain, posted 07-25-2009 9:26 PM crawler30 has not replied

  
Perdition
Member (Idle past 3237 days)
Posts: 1593
From: Wisconsin
Joined: 05-15-2003


Message 114 of 217 (516265)
07-24-2009 11:34 AM
Reply to: Message 113 by crawler30
07-24-2009 11:06 AM


But see the point is that the mainstream Darwinian view of evolution says that life changes on accident,
Not quite, but close enough for this post, I guess.
but how can you explain this when you point out the nylon eating bacteria? A new niche opened up for an organizm to fill, so it was filled by a bacteria whom never existed before.
Again, not quite. I don't know the exact lineage, but there would have been bacteria that ate other types of cloth, probably wool or cotton. The fact that nylon is synthetic doesn't mean it would take more than a single mutation to allow it to eat nylon.
This would lead me to believe that it purposefully happened because there was a reason to have happened.
There's a reason for a lot of things to happen which haven't. Just because you can conceive of a reason doesn't mean that was actually how or why it happened in reality.
For instance, what reason would this species have come into being, obviously they had enough food to survive as they were so why the new diet?
Well, maybe there wasn't a lot of food where they were. Imagine if we have a cotton eating macteria. It's happily munching on your underwear, when you decide to wear that particulr pair of underwear. You pick it up, and a couple bacteria fall off onto the bra sitting next to your underwear pile. There's no longer a lot of cotton, but luckily, one of the bacteria had the mutation to allow it to digest nylon, and as the rest of the bacteria die, it happily munches on, dividing and creating a new lineage of nylon eating bacteria.
Another reason is even more likely. A lot of bacteria are happily munching on cotton, and none are munching on the nylon near by. One bacterium gets the ability to eat nylon, and finds, "Hey, I have no competition here! I can eat all I want with no effort!" Again, it starts happily munching nylon where it doesn't have to compete, and starts dividing. Eventually, the nylon is just as congested as the cotton, but the two lines of bacteria are no longer the same.
Because it could? Maybe it was because for eveything on earth, nothing is ever wasted, even excriment has its role in life. And every niche gets filled appearently some very quickly as these bacteria have shown.
Correct, but that's a direct consequence of evolution. If an evolution allows an individual to access a resource that nothing else is using, then it has no competition and will live a long time, mating and passing on it's genes as it does, letting more animals use this untapped resource. Eventually, the new type and the old will develop more mutations, further dirving them apart until they can no longer interbreed, and viola, we have a new species.
BTW I did not join this forum to ridicule others for their beliefs or be ridiculed, I am here to learn with an open mind. I personally believe in God, but I do not expect everyone else to.
Welcome to the forum. We try not to ridicule people here, in fact, it's against the forum rules, but we won't hand-hold either. If someone's position is ridiculous, there are a lot of very smart people on here who will tear it apart. Quite often, this can seem rude or insensitive to the person who's position is getting ripped apart, but it's not meant personally...usually.

This message is a reply to:
 Message 113 by crawler30, posted 07-24-2009 11:06 AM crawler30 has replied

Replies to this message:
 Message 115 by crawler30, posted 07-24-2009 12:33 PM Perdition has replied

  
crawler30
Junior Member (Idle past 4776 days)
Posts: 15
From: Florida
Joined: 07-23-2009


Message 115 of 217 (516276)
07-24-2009 12:33 PM
Reply to: Message 114 by Perdition
07-24-2009 11:34 AM


you used the nylon eating bacteria as an observation of evolution but if no one observed the mutation only the outcome and the lineage has not been identified, then how was this "evolution" observed? I understand that it is a new species but I am not sure how to classify it as having been observered to have changed. A scientific observation includes the entire change or the residual effects of the change, such as energy release etc. which would not solely be based on the fact that there was suddenly one day a new species itself in an uncontrolled environment with any number of species and outside influences acting on the lineage of this new species. Right?

This message is a reply to:
 Message 114 by Perdition, posted 07-24-2009 11:34 AM Perdition has replied

Replies to this message:
 Message 116 by Perdition, posted 07-24-2009 12:47 PM crawler30 has not replied
 Message 120 by Rrhain, posted 07-25-2009 9:57 PM crawler30 has not replied

  
Perdition
Member (Idle past 3237 days)
Posts: 1593
From: Wisconsin
Joined: 05-15-2003


Message 116 of 217 (516280)
07-24-2009 12:47 PM
Reply to: Message 115 by crawler30
07-24-2009 12:33 PM


but if no one observed the mutation only the outcome and the lineage has not been identified, then how was this "evolution" observed?
I said I didn't know the particulars. The original strain was discovered in a pond outside a nylon factory. It has since been duplicated in a different type of bacteria:
wikipedia writes:
Scientists have also been able to induce another species of bacteria, Pseudomonas aeruginosa, to evolve the capability to break down the same nylon byproducts in a laboratory by forcing them to live in an environment with no other source of nutrients. The P. aeruginosa strain did not seem to use the same enzymes that had been utilized by the original Flavobacterium strain.[5] Other scientists were able to get the ability to generate the enzymes to transfer from the Flavobacterium strain to a strain of E. coli bacteria via a plasmid transfer.[6]
Regardless, the fact that a nylon eating bacterium couldn't live until we developed nylon, a completely synthetic fiber, it must be a new species. Unless you're postulating that it somehow just zapped into being, sharing many similarities to another type of bacteria, except for one difference, seems to be reaching a bit.
A scientific observation includes the entire change or the residual effects of the change, such as energy release etc. which would not solely be based on the fact that there was suddenly one day a new species itself in an uncontrolled environment with any number of species and outside influences acting on the lineage of this new species. Right?
Nope. Technically, a scientific observation is merely an observation. If you know all the characteristics of the change, that makes a lot of your job easier, but all you need is seeing an unusual type of stone on a path to begin an investigation of how it got there. You can then discover that a construction crew that built the path brought in gravel from a quarry 50 miles away. You have your answer despite not having seen the actual gravel being harvested, delivered, or dumped.

This message is a reply to:
 Message 115 by crawler30, posted 07-24-2009 12:33 PM crawler30 has not replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 117 of 217 (516503)
07-25-2009 4:07 PM
Reply to: Message 113 by crawler30
07-24-2009 11:06 AM


But see the point is that the mainstream Darwinian view of evolution says that life changes on accident, but how can you explain this when you point out the nylon eating bacteria? A new niche opened up for an organizm to fill, so it was filled by a bacteria whom never existed before. This would lead me to believe that it purposefully happened because there was a reason to have happened.
The trouble is that there's no mechanism which allows the right mutation to happen just because it's a good idea. How would the bacteria know?
On the other hand, there is a mechanism (or perhaps I should say the failure of a mechanism) which produces mutations (good, bad, and neutral) at random: natural selection then selects those which are a good idea.
For instance, what reason would this species have come into being, obviously they had enough food to survive as they were so why the new diet?
It came into being by chance.
To see why it was favored by selection, consider the following. You say that the species "obviously had enough food to survive". This is true, but remember that selection operates on individuals. Just because the species has enough food to survive and reproduce doesn't mean that every individual has enough food to survive and reproduce --- indeed, this cannot be so, for otherwise the original population of bacteria would grow exponentially, which is impossible while their supply of food remains constant. (It was this consideration that led Darwin to think up his theory in the first place.)
The first bacterium to get the nylonase mutation had a supply of food for which it had no competitors. There is always a selective advantage to moving into an empty niche.
---
I hope this helps.

This message is a reply to:
 Message 113 by crawler30, posted 07-24-2009 11:06 AM crawler30 has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 118 of 217 (516523)
07-25-2009 9:06 PM
Reply to: Message 110 by crawler30
07-23-2009 11:50 PM


crawler30 responds to me:
quote:
Such as dog breeding, is that or is not intelligent design?
No, it's evolution through artificial selection. Breeding programs don't create specific mutations. They take advantage of mutations that come up and work to propagate them through a species.
quote:
But in what way have we acctually obsereved as scientists the effects of evolution without any outside influence.
By not actually doing anything to the organisms as they go through their reproductive cycles. Instead, we just observe them.
quote:
But the fact remains that if you leave things to their own devices man has never noted any significant changes in a population over time.
Incorrect. The exact opposite is true. When we leave things to their own devices, we have ALWAYS noted significant changes in a population over time.
Surel you've heard of the peppered moths in the UK, yes? Most of types of a certain moth in the 1800s were white. This made it very easy for them to be camouflaged on the white lichens of the trees in the area in which they lived. But then the Industrial Revolution happened and the lichens became covered in soot. Being white was no longer good camouflage.
However, there was an allele in the population that had the moths be black, not white. This variation was good for being camouflaged on soot-blackened trees and it became the dominant allele.
But then, environmental regulations were put in place and the soot was no longer being pumped into the air. The lichens returned, white as they ever were, and those black moths were no longer camouflaged. The white variation returned to the dominant position.
That's just a simplistic view. If you get into more deep field and lab work, you find speciation, even new genera and families.
quote:
And if we had then natural selection would be thrown out the window because appearently it happens faster than, natural selection would allow for an entire population to change into a new spieces.
Incorrect. We have observed reproductive isolation in as few as 13 generations.
No human interaction involved.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

This message is a reply to:
 Message 110 by crawler30, posted 07-23-2009 11:50 PM crawler30 has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 119 of 217 (516525)
07-25-2009 9:26 PM
Reply to: Message 113 by crawler30
07-24-2009 11:06 AM


crawler30 writes:
quote:
But see the point is that the mainstream Darwinian view of evolution says that life changes on accident
Incorrect. Evolution is decidedly NOT an "accident." Evolution is not random because selection is not random. Mutations are a random component (though not completely so), but selection is not random.
quote:
For instance, what reason would this species have come into being
Because there was nothing stopping it. The mutation that led to the ability to digest nylon oligimers was a single frameshift mutation, a random event. But it turns out that the environment selected for this mutation to be beneficial and provide a reproductive advantage: These bacteria could process a new food source that other bacteria could not. Thus, they were not subject to competition for this food source from the other bacteria and thus they could survive in ways the other bacteria could not.
quote:
And every niche gets filled appearently some very quickly as these bacteria have shown.
Indeed. So? Why is this a problem?

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

This message is a reply to:
 Message 113 by crawler30, posted 07-24-2009 11:06 AM crawler30 has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 120 of 217 (516527)
07-25-2009 9:57 PM
Reply to: Message 115 by crawler30
07-24-2009 12:33 PM


crawler30 writes:
quote:
but if no one observed the mutation only the outcome and the lineage has not been identified, then how was this "evolution" observed?
Because we sequenced the genome and was able to determine exactly how it happened. It is the result of a single frameshift mutation.
quote:
A scientific observation includes the entire change or the residual effects of the change, such as energy release etc. which would not solely be based on the fact that there was suddenly one day a new species itself in an uncontrolled environment with any number of species and outside influences acting on the lineage of this new species. Right?
Wrong. A scientific observation would include morphological and genetic data...which is exactly what was done. That's why we know that this is a new type of bacteria based upon a single frameshift mutation.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

This message is a reply to:
 Message 115 by crawler30, posted 07-24-2009 12:33 PM crawler30 has not replied

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024