For Danmac - Abiogenesis

[Danmac]

THEY DIDN'T INTERFERE! They tried to reproduce the same atmosphere that early earth may have had.

Here are some critical thinking questions.........

1. How much of the experiment was left to chance processes or how much involved intelligent design?
2. How did Miller know what Earth’s early atmosphere (billions of years ago) was like?
3. Did Miller produce the right type of amino acids used in life?

 

[Autodidact]

Can we rule out intelligent design?

Why don't you tell us what you mean by that term.

 

[tumbleweed41]

Here are some critical thinking questions.........

1. How much of the experiment was left to chance processes or how much involved intelligent design?
2. How did Miller know what Earth’s early atmosphere (billions of years ago) was like?
3. Did Miller produce the right type of amino acids used in life?

Prime example of creationist logic.

If a biochemist were to recreate the exact conditions believed to have been present during abiogenesis, and as a result of years of careful experiments, was to create a living biological organism, the creationist response would be...
"Well, how do we know that that is the same type of organism that supposedly started billions of years ago. I want to see it evolve into a duck!"

 

[Commoner]

Prime example of creationist logic.

If a biochemist were to recreate the exact conditions believed to have been present during abiogenesis, and as a result of years of careful experiments, was to create a living biological organism, the creationist response would be...
"Well, how do we know that that is the same type of organism that supposedly started billions of years ago. I want to see it evolve into a duck!"

Even if that were possible, they'd simply retreat to: well, animals evolve, but humans - no, no... We've never seen a human evolve from a duck.

 

[Danmac]

Prime example of creationist logic.

If a biochemist were to recreate the exact conditions believed to have been present during abiogenesis, and as a result of years of careful experiments, was to create a living biological organism, the creationist response would be...
"Well, how do we know that that is the same type of organism that supposedly started billions of years ago. I want to see it evolve into a duck!"

1} Miller had to isolate the amino acids from the environment he created them in or else it would have destroyed them. No such system could have existed in a primative Earth.

2)The atmosphere they created was an oxygen free atmosphere. It would be impossible in an oxygen environment. There is no evidence to support an oxygen free primitive Earth. In fact, Earth's oldest rocks contain evidence of being formed in an atmosphere that contained oxygen.

3)The ozone is made of oxygen. Without it the suns ultraviolet rays would have destroyed any biological molecules.

 

[DeitySlayer]

1} Miller had to isolate the amino acids from the environment he created them in or else it would have destroyed them. No such system could have existed in a primative Earth.

2)The atmosphere they created was an oxygen free atmosphere. It would be impossible in an oxygen environment. There is no evidence to support an oxygen free primitive Earth. In fact, Earth's oldest rocks contain evidence of being formed in an atmosphere that contained oxygen.

3)The ozone is made of oxygen. Without it the suns ultraviolet rays would have destroyed any biological molecules.

You ignore the presence of lipid vesicles and the fact that ozone is not present at ground level, or in the deep sea, where these molecules formed.

 

[tumbleweed41]

1} Miller had to isolate the amino acids from the environment he created them in or else it would have destroyed them. No such system could have existed in a primative Earth.

1. Since his first experiment, Miller and others have experimented with other atmospheric compositions, too (Chang et al. 1983; Miller 1987; Schlesinger and Miller 1983; Stribling and Miller 1987). Complex organic molecules form under a wide range of prebiotic conditions.
2. It is possible that life arose well away from the atmosphere -- for example, around deep-sea hydrothermal vents. This could make the atmospheric content largely irrelevant.
3. The early atmosphere, even if it was oxidizing, was nowhere near as oxidizing as it is today. It was likely high in hydrogen, which facilitates the formation of organic molecules (Tian et al. 2005).

2)The atmosphere they created was an oxygen free atmosphere. It would be impossible in an oxygen environment. There is no evidence to support an oxygen free primitive Earth. In fact, Earth's oldest rocks contain evidence of being formed in an atmosphere that contained oxygen.

1. There is a variety of evidence that the early atmosphere did not have significant oxygen (Turner 1981).
   • Banded iron formations are layers of hematite (Fe2O3) and other iron oxides deposited in the ocean 2.5 to 1.8 billion years ago. The conventional interpretation is that oxygen was introduced into the atmosphere for the first time in significant quantities beginning about 2.5 billion years ago when photosynthesis evolved. This caused the free iron dissolved in the ocean water to oxidize and precipitate. Thus, the banded iron formations mark the transition from an early earth with little free oxygen and much dissolved iron in water to present conditions with lots of free oxygen and little dissolved iron.
   • In rocks older than the banded iron formations, uranite and pyrite exist as detrital grains, or sedimentary grains that were rolling around in stream beds and beaches. These minerals are not stable for long periods in the present high-oxygen conditions.
   • "Red beds," which are terrestrial sediments with lots of iron oxides, need an oxygen atmosphere to form. They are not found in rocks older than about 2.3 billion years, but they become increasingly common afterward.
   • Sulfur isotope signatures of ancient sediments show that oxidative weathering was very low 2.4 billion years ago (Farquhar et al. 2000).
   
   The dominant scientific view is that the early atmosphere had 0.1 percent oxygen or less (Copley 2001).
2. Free oxygen in the atmosphere today is mainly the result of photosynthesis. Before photosynthetic plants and bacteria appeared, we would expect little oxygen in the atmosphere for lack of a source. The oldest fossils (over a billion years older than the transition to an oxygen atmosphere) were bacteria; we do not find fossils of fish, clams, or other organisms that need oxygen in the oldest sediments.

3)The ozone is made of oxygen. Without it the suns ultraviolet rays would have destroyed any biological molecules.

1. When simple organic molecules are held together in a fairly concentrated area, such as stuck to a dust or ice grain, the UV light actually enhances the formation of more complex molecules by breaking some bonds and allowing the molecules to recombine (Bernstein et al. 1999; Cooper et al. 2001). DNA and RNA are relatively resistant to UV light, because some parts of the molecules shelter others and damage to the bases can provide the materials to repair the backbone. UV light gives nucleic acids a selective advantage and may in fact have been an essential ingredient for abiogenesis (Mulkidjanian et al. 2003; Mullen 2003).
2. The molecules need not all have stayed exposed to UV for long. Some would have dissolved in oceans and lakes. In one proposed scenario, the complex organic molecules form in the deep ocean around geothermal vents, well away from ultraviolet light.

Source

 

[Autodidact]

Danmac: If you're trying to attack the experimental protocol, please think, difficult as that may be for you. First, you know nothing about it. Second, people who do did their best for 50 years to attack from every corner. After that process, we now know pretty well what that particular experiment shows, and what it failed to show. We really don't need any amateurish attempts from some ignorant guy on the internet to help with that. But thanks for trying.

 

[Danmac]

You ignore the presence of lipid vesicles and the fact that ozone is not present at ground level, or in the deep sea, where these molecules formed.

Hodrolysis

 

[Danmac]

Danmac: If you're trying to attack the experimental protocol, please think, difficult as that may be for you. First, you know nothing about it. Second, people who do did their best for 50 years to attack from every corner. After that process, we now know pretty well what that particular experiment shows, and what it failed to show. We really don't need any amateurish attempts from some ignorant guy on the internet to help with that. But thanks for trying.

Then why are you asking me questions?

 

[Commoner]

Hodrolysis

Hydrolysis?

 

[Danmac]

1. Since his first experiment, Miller and others have experimented with other atmospheric compositions, too (Chang et al. 1983; Miller 1987; Schlesinger and Miller 1983; Stribling and Miller 1987). Complex organic molecules form under a wide range of prebiotic conditions.

1. Why did they experiment with "other atmospheric conditions" if Miller Urey conditions were scientifically accurate?

2. It is possible that life arose well away from the atmosphere -- for example, around deep-sea hydrothermal vents. This could make the atmospheric content largely irrelevant.

   The words "possible" and "could" point to speculation.

   [*] The early atmosphere, even if it was oxidizing, was nowhere near as oxidizing as it is today. It was likely high in hydrogen, which facilitates the formation of organic molecules (Tian et al. 2005).

   What do you mean, "even if it was". Don't they know?

1. There is a variety of evidence that the early atmosphere did not have significant oxygen (Turner 1981).
   • Banded iron formations are layers of hematite (Fe2O3) and other iron oxides deposited in the ocean 2.5 to 1.8 billion years ago. The conventional interpretation is that oxygen was introduced into the atmosphere for the first time in significant quantities beginning about 2.5 billion years ago when photosynthesis evolved. This caused the free iron dissolved in the ocean water to oxidize and precipitate. Thus, the banded iron formations mark the transition from an early earth with little free oxygen and much dissolved iron in water to present conditions with lots of free oxygen and little dissolved iron.

1. • The conventional interpretation heh.

     [*] "Red beds," which are terrestrial sediments with lots of iron oxides, need an oxygen atmosphere to form. They are not found in rocks older than about 2.3 billion years, but they become increasingly common afterward.
     [*] Sulfur isotope signatures of ancient sediments show that oxidative weathering was very low 2.4 billion years ago (Farquhar et al. 2000).

   The dominant scientific view is that the early atmosphere had 0.1 percent oxygen or less (Copley 2001).
   [*] Free oxygen in the atmosphere today is mainly the result of photosynthesis. Before photosynthetic plants and bacteria appeared, we would expect little oxygen in the atmosphere for lack of a source. The oldest fossils (over a billion years older than the transition to an oxygen atmosphere) were bacteria; we do not find fossils of fish, clams, or other organisms that need oxygen in the oldest sediments.

1. When simple organic molecules are held together in a fairly concentrated area, such as stuck to a dust or ice grain, the UV light actually enhances the formation of more complex molecules by breaking some bonds and allowing the molecules to recombine (Bernstein et al. 1999; Cooper et al. 2001). DNA and RNA are relatively resistant to UV light, because some parts of the molecules shelter others and damage to the bases can provide the materials to repair the backbone. UV light gives nucleic acids a selective advantage and may in fact have been an essential ingredient for abiogenesis (Mulkidjanian et al. 2003; Mullen 2003).
2. The molecules need not all have stayed exposed to UV for long. Some would have dissolved in oceans and lakes. In one proposed scenario, the complex organic molecules form in the deep ocean around geothermal vents, well away from ultraviolet light.

Source

You realize all of this is based on assumption and not findings.

 

[Danmac]

Hydrolysis?

Aminos cannot bond in water.

 

[DeitySlayer]

Aminos cannot bond in water.

The point is redundant anyway because of the lipid vesicles.

 

[Autodidact]

Hodrolysis

What's that?

 

[Autodidact]

Why did they experiment with "other atmospheric conditions" if Miller Urey conditions were scientifically accurate?
[*] The words "possible" and "could" point to speculation. What do you mean, "even if it was". Don't they know?
[/list]


The conventional interpretation heh.
You realize all of this is based on assumption and not findings.

What assumptions are you referring to?

 

[Autodidact]

Then why are you asking me questions?

You mean like asking you to define your terms? So we can have an intelligent discussion.

Speaking of which, as is your wont, you never did tell us what you meant by "intelligent design."

 

[Danmac]

What assumptions are you referring to?

Do you ever notice how often you see words like, could, may have, possibly, etc. when scientists talk about macroevolution?

 

[Danmac]

Speaking of which, as is your wont, you never did tell us what you meant by "intelligent design."

I think the term is self explanatory. Stop playing word games.

 

[DeitySlayer]

Do you ever notice how often you see words like, could, may have, possibly, etc. when scientists talk about macroevolution?

Example?