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Author Topic:   Are there evolutionary reasons for reproduction?
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 80 of 136 (559850)
05-11-2010 8:33 PM
Reply to: Message 1 by MrQ
04-04-2010 6:18 PM


Hmmmm....
I`m a little more than confused about the question. I don`t understand if you want what CAUSES reproduction, or WHY reproduction occurs...but in most organisms, when they mature, ATP triggers DNA that activate sex organs. When the sex organs are active, the brain instinctively wants to reproduce during some particular time, be it a certain year, season, or hour, depending on the organism you are talking about.
In the broader perspective, evolution does not answer the question, why animals have male and female partners. Evolution explains asexual organisms, and could (by a stretch) explain hermaphroditic species, such as the flat worm. In order for male-female reproduction to occur, you require two members of the same species to evolve at the same time, because without a suitable partner to mate with (within it`s lifetime), the organism carrying the suitable mutations for this to occur would die. Now, by suitable, this is very specific. Because there are hundreds of species that interbreed, and are not sexually functional. A great example of this is the horse and the donkey giving birth to a sexually non-functional mule.
I hope this answers some of your questions, and perhaps asks some new ones.
Dennis.

This message is a reply to:
 Message 1 by MrQ, posted 04-04-2010 6:18 PM MrQ has not replied

Replies to this message:
 Message 81 by Dr Adequate, posted 05-12-2010 3:04 AM dennis780 has replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 82 of 136 (559917)
05-12-2010 3:50 AM
Reply to: Message 81 by Dr Adequate
05-12-2010 3:04 AM


Re: Hmmmm....
"the other sex doesn't need to evolve at the same time as such."
Wrong. Supposing that one organism of a species evolves, making the others female by default. The male must find a suitable female of the same species with proper sex organs to fertilize for offspring. Although in theory, you are correct in your assumption, it does not answer the question, how does he mate with she? If the female has not evolved, then the process of male/female reproduction is irrelevant, because for this species to exist in the first place, it would have to be asexual, so without any genetic change, it would not require a male for reproduction. The male with genetic change would not find a suitable partner, and die, losing any traits it possessed.
Second, even if two of the same species did evolve simultanously, the genes would have to match, or the offspring would receive half information from each respective parent, but the information would not match, making the offspring sexually inactive.
Third, asexual reproduction seems favourable (to me), in that it preserves a line of genetic information perfectly, and does not require the finding of a suitable mate. Populations grow faster, giving them a distinct advantage.

This message is a reply to:
 Message 81 by Dr Adequate, posted 05-12-2010 3:04 AM Dr Adequate has replied

Replies to this message:
 Message 83 by Dr Adequate, posted 05-12-2010 4:17 AM dennis780 has replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 84 of 136 (559930)
05-12-2010 4:45 AM
Reply to: Message 83 by Dr Adequate
05-12-2010 4:17 AM


Re: Hmmmm....
"As you would know if you were interested in biology, the regular way for marine species to mate is for the happy couple to emit their gametes in roughly the same place at the same time. What they both need is a hole for the emission of gametes, and this would be basal to the species by hypothesis."
I was refering to reproductive organs such as the penis, but I can do fish as well.
Both mutations still have to occur at the same time. If the female lays eggs, but no males have developed, no fertilization. If male developes but no eggs, nothing to fertilize. Same problem.
" You had already conceded the possibility of species that reproduced sexually"
Asexually
"Again, by conceding sexual reproduction at all, you're supposing this problem to have been solved."
Asexual reproduction, yes. Male/female, no. Your dancing. I can feel it.
"And again, I would remind you that you conceded sexual reproduction"
Asexual reproduction. Yes. Why the hell would I concede the point I am debating? Your not making any sense.
I get it. YOU don't know. Do you? You really don't know. And like every other evolutionist that meets a creationist with a valid point, you do they ol' I know you are but what am I? hahahahaha. Your funny. I think I'll keep you.

This message is a reply to:
 Message 83 by Dr Adequate, posted 05-12-2010 4:17 AM Dr Adequate has replied

Replies to this message:
 Message 85 by Dr Adequate, posted 05-12-2010 5:22 AM dennis780 has replied
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dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 86 of 136 (560239)
05-13-2010 10:17 PM
Reply to: Message 85 by Dr Adequate
05-12-2010 5:22 AM


Re: Hmmmm....
"The original species, by hypothesis, released identical haploid gametes which fertilized one another."
I don`t disagree with hermaphroditic sex. This would follow accurately the evolutionary trend.
At some given point in history, organisms must have made a switch to male/female reproduction. Since each sex would have needed to evolve at the same time, this seems like a roadblock on the evolutionary highway.
"I therefore took as my starting point a species which reproduced sexually but did not have distinct sexes, which was what you apparently wanted explaining."
As I said before, I have no issues with asexual reproduction, or hermaphroditic reproduction, as these to not REQUIRE the opposite sex for reproduction. My issue is, and always has been, with male/female reproduction.

This message is a reply to:
 Message 85 by Dr Adequate, posted 05-12-2010 5:22 AM Dr Adequate has replied

Replies to this message:
 Message 87 by Dr Adequate, posted 05-14-2010 12:26 AM dennis780 has not replied
 Message 88 by bluescat48, posted 05-14-2010 12:29 AM dennis780 has not replied
 Message 93 by Modulous, posted 05-15-2010 9:00 AM dennis780 has replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 95 of 136 (561079)
05-18-2010 7:04 PM
Reply to: Message 93 by Modulous
05-15-2010 9:00 AM


Re: all gametes great and small
You will have to excuse my short reply, I'm respondig on my iPhone. I agree that the new smaller seeds would be related to the previous bigger seeds. Although I'm unsure what organism you are talking about. This does not address the question of male/female reproduction.
What you are refering to sounds like either germination, or asexual reproduction, in which the opposite sex plays no part in the reproductive process. Pointing out that fertilization of eggs is the only way an organism only futhurs my point that for both sexes of a species to exist, both sexes are required.
Now later in your post you refer to a biological law that species become specialized to increase their ability to survive. What you are refering to is adaptation, which is the ability for an organism to change to better Suit it's environment. Evolution is a series of random mutations that over time become useful (or microevolution, whichever you prefer). Macroevolution is based on pure random mutation.
I have to go, my youngest is starting to cry. I will post again to address your Other points. I apologize.
If a hypothetical organism laid any number of eggs (the amount is irrelevant), without a suitable opposite sex, the eggs would die. This could continue until the organism capable of male/female reproduction would no longer be fertile, or die.

This message is a reply to:
 Message 93 by Modulous, posted 05-15-2010 9:00 AM Modulous has replied

Replies to this message:
 Message 96 by Modulous, posted 05-18-2010 9:30 PM dennis780 has not replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 98 of 136 (562466)
05-29-2010 12:56 AM
Reply to: Message 97 by Asking
05-19-2010 7:08 PM


"Some organisms do breed asexually but tend not to do very well in the long run if they do not resort to sexual reproduction at some point or have some other means of altering their genetic material."
any examples of any animal adding to it's genetic code? (excluding pre existing information).
Actually, the most abundant organisms in the world reproduce asexually. Almost all bacteria reproduce this way.
"life possibly originated through the differential survival of replicating molucules"
but since we are attempting to deal with data, not theories, I would like some sort of reconstructed experiment somewhere supporting your theory.

This message is a reply to:
 Message 97 by Asking, posted 05-19-2010 7:08 PM Asking has replied

Replies to this message:
 Message 99 by Asking, posted 05-29-2010 6:19 AM dennis780 has replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 101 of 136 (563714)
06-06-2010 3:51 PM
Reply to: Message 99 by Asking
05-29-2010 6:19 AM


"Evolution operates through the modification of existing genetic material"
Wrong, or single celled organisms would have the information required to code for all of any organisms traits and physical features. Evolution requires adding of new information over time.
"As far as I know genetic material doesn't just appear out of nothing"
I won't argue with you.
"available evidence points to it being the product of pre-existing genetic material."
Although I'm sure this is a topic for another thread, I'm curious to know what information this is exactly...is there a thread for this?
"Gene duplication - http://171.66.122.45/content/9/7/629.full "
This has no information on new information, only existing information. Furthurmore, it goes into great deal about cloning. I'm not sure if I mentioned this before, but similarity is also support for design. Since all cars have spark plugs, steering wheels, tires, seats, transmissions, doors, frames, etc., they too were designed. Genetic similarities in ape vision and human vision only shows that they are similar. Not that they are related.
Although this is irrelevant to the topic on this thread, I'll reply briefly, since you do not need to discuss the 256 bp similarities to know that human eyes are not related to Apes of any kind.
Since Apes have brown eyes, their alleles code for AA (A or a being dominant or recessive traits respectively). Since brown eyes are dominant, and apes are homogenius dominant A, it's not possible for humans to have any recessive colors of eyes, such as blue or green. Even if by random mutation, one member of a primative species (that led to humaniods today) did get a recessive (a), the odds of the offspring recieving that trait is still 0%, as the mate would be AA, and the other would be Aa, leaving only the possibility of AA (50%), or Aa (50%). The offspring (if coded for Aa from the respective mate) would have the same odds, 50/50, but eye colour would still be brown as 2 recessive genes are required (aa).
"Benefitial mutations are restricted to a single lineage and cannot be rapidly distributed within a population"
I agree completely.
"as most mutations are either neutral or detrimental the net effect of asexual reproduction is a reduction in fitness."
I agree as well. However, asexual reproduction has it's advantages as well.
1. Asexual organisms do not have to search for a mate, and this leads to greater population growth.
2. Greater populations have greater chances of survival if there is any habitat change (be it preditorial, or environmental), and greater numbers also means out-completing organisms of similar nature for nutrients and water.
"origins of life at hydrothermal vents"
Read about this years ago. The logical mind refutes this instantly, since incomplete chemical structures travelling from land to the ocean floor sounds like a fairy tale. Even so, supposing this is even plausible, you still do not have DNA or mRNA to allow for reproduction. You also do not have more complex structures such as protiens (that are required for reproduction, orientation, and oxygen distribution). You do not have any usable information (such as DNA), that can be copied, that is stable, and that contains useful information.
"Returning to the original point have I answered the query as to what evolutionary reasons there are for sexual reproduction?"
I'm not sure why this question is asked. Even I can argue for evolution on this point, that without reproduction, life would cease to exist. I think we're in the wrong thread. Is there one for the topic we are getting into?

This message is a reply to:
 Message 99 by Asking, posted 05-29-2010 6:19 AM Asking has replied

Replies to this message:
 Message 102 by Huntard, posted 06-06-2010 4:12 PM dennis780 has not replied
 Message 103 by Asking, posted 06-06-2010 4:30 PM dennis780 has replied
 Message 106 by misha, posted 06-22-2010 8:34 AM dennis780 has replied
 Message 109 by Coragyps, posted 06-26-2010 2:56 PM dennis780 has replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 104 of 136 (565897)
06-21-2010 11:42 PM
Reply to: Message 103 by Asking
06-06-2010 4:30 PM


"Gene duplication creates more genetic material from existing genetic material upon which evolution can act."
I'm going to assume that you didn't know that almost all organisms today have error checking systems for DNA both before and after recombination.
"Your first point is true but your second point is way of the mark. It doesn't matter if there are a million individuals in a population if they can't evolve quickly enough to keep up with changes in their environment."
Let me explain this better. Asexual organisms would out-compete organisms that breed male/female, in the case of an earthquake, or flood (just examples). This is because for any organism breeding male/female, a suitable partner is required. Asexual organisms would deal better with this case, since even alone, they can reproduce.
"There is a much better account of this in Nick Lanes book on evolution and in his account its a combination of hydrothermal chemistry and self-replicating RNA. It doesn't require proteins when RNA can replicate itself."
Your right. But without enzymes, there is no chemical reaction to produce ribonucleic acid, the back bone for DNA and RNA.

This message is a reply to:
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Replies to this message:
 Message 105 by Wounded King, posted 06-22-2010 4:37 AM dennis780 has replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 107 of 136 (566738)
06-26-2010 1:54 PM
Reply to: Message 105 by Wounded King
06-22-2010 4:37 AM


Re: Look Ma, no enzymes!
"Should we also assume that you didn't know such mechanisms are far from perfect"
quote:
Cellular proofreading and error toe-checking mechanisms ensure near perfect fidelity for DNA replication.
DNA replication - Wikipedia
Wiki seems to be on my side.
"This is not really correct, both purines (A,G) and pyrimidines (C,T,U) can be produced from prebiotic precursors without the need for any enzymes"
This may be true, but you are missing the point. Without the presence of oxygen in the atmosphere, there wouldn't be an ozone (O3) layer, protecting the earth from harmful radiation.
And perhaps even though it is plausible that certain purines could exist, you would need more than two to form useful information in RNA. With only two nucleic acids (adenine and guanine), you still do not have a complete RNA, that accomplishes three main things:
1. Is stable (without ribonucleic acid)
2. Can be copied.
3. Contains useful information. (The only sequence possible with two acids is AG, or GA. However, Adenine and Guanine do not pair today, so this is unlikely. Regardless, you have no useful information).
"alternative chemical routes to RNA production which have yet to be properly explored"
Then I suppose we will get to them when the scientists do, hey? Can I say evidence for creation is the returning of God to judge the world? No, because it hasn't happened yet, so it's out.

This message is a reply to:
 Message 105 by Wounded King, posted 06-22-2010 4:37 AM Wounded King has replied

Replies to this message:
 Message 111 by Wounded King, posted 06-27-2010 6:11 AM dennis780 has replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 108 of 136 (566740)
06-26-2010 2:18 PM
Reply to: Message 106 by misha
06-22-2010 8:34 AM


"In your hypothetical situation ALL apes have brown eyes and the allele combination AA."
This is not hypothetical, since all apes have brown eyes, which would suggest that any common ancestor to humans and apes did not have any such mutation.
"So, the probability of a recessive gene holding in a population and being expressed is not 0%. As long as Aa parents reproduce the probability of producing an "aa" offspring is close to 100%.
dennis780 writes:
Since Apes have brown eyes, their alleles code for AA (A or a being dominant or recessive traits respectively). Since brown eyes are dominant, and apes are homogenius dominant A, it's not possible for humans to have any recessive colors of eyes, such as blue or green. Even if by random mutation, one member of a primative species (that led to humaniods today) did get a recessive (a), the odds of the offspring recieving that trait is still 0%, as the mate would be AA, and the other would be Aa, leaving only the possibility of AA (50%), or Aa (50%). The offspring (if coded for Aa from the respective mate) would have the same odds, 50/50, but eye colour would still be brown as 2 recessive genes are required (aa).
I don't believe you have thought this through at all. Either that or you are severely lacking in logical skills. You've forgotten to go one generation further.
1. In your hypothetical situation ALL apes have brown eyes and the allele combination AA.
2. You state that if ONE ape has a genetic mutation resulting in a recessive "a" allele that the probability of this genetic variation persisting is 0%. This is not only wrong its HORRIBLY wrong.
EX:
Generation 1: All AA except one mutant Aa
Generation 2: All AA parent pairs produce AA offspring. However, Aa parent produces 50% Aa offspring.
Generation 3: All AA parent pairs produce AA offspring. AA/Aa parent pairs produce 50% Aa offspring. However, if two of the Aa offspring from Generation 2 reproduce together they produce 25% AA, 50% Aa and 25% aa offspring.
So, the 3rd Generation is the first in which a recessive allele mutation could possibly show up. Granted it is more likely that it won't show up in the 3rd Generation but it is inevitable that it will show up. As long as Aa parents continue to reproduce they will produce 50% Aa offspring and so sooner or later the population will have enough Aa offspring for these to reproduce together, resulting in an "aa" offspring.
So, the probability of a recessive gene holding in a population and being expressed is not 0%. As long as Aa parents reproduce the probability of producing an "aa" offspring is close to 100%."
If apes were monogamous, this would be true. But since most species of primate breed polygamously, the odds do not increase as quickly as in monogamous. Supposing Genetic mutated (Aa) was born, and passed on to offspring (Aa) and (Aa), (25% chance respectively...unlikely, but plausible). Offspring would breed outside family line with other (AA) in troop (25% respectively). During which, of course, (AA) continues to reproduce with (AA), 100% chance of (AA). The likelihood of passing (Aa) until (Aa) and (Aa) create (aa) is so minute, it hurts my brain to think about it.

This message is a reply to:
 Message 106 by misha, posted 06-22-2010 8:34 AM misha has not replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 112 of 136 (575745)
08-20-2010 10:40 PM
Reply to: Message 109 by Coragyps
06-26-2010 2:56 PM


Yes. Apes all have a dark-hued sclera, or various shades of brown eyes. As does the one you posted.

This message is a reply to:
 Message 109 by Coragyps, posted 06-26-2010 2:56 PM Coragyps has not replied

Replies to this message:
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dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 113 of 136 (575746)
08-20-2010 10:41 PM
Reply to: Message 110 by Theodoric
06-26-2010 3:15 PM


Re: Heres another
I'm actually with you on this one Theo. Thats one human looking monkey.

This message is a reply to:
 Message 110 by Theodoric, posted 06-26-2010 3:15 PM Theodoric has not replied

Replies to this message:
 Message 115 by bluescat48, posted 08-21-2010 12:03 AM dennis780 has not replied

  
dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 114 of 136 (575748)
08-20-2010 10:59 PM
Reply to: Message 111 by Wounded King
06-27-2010 6:11 AM


Re: Look Ma, no enzymes!
"As an error correcting mechanism it is very efficient, but the sheer volumes of genetic material involved mean that mutations are an inevitable result."
I'm not sure if you're still talking about Macro evolution. Since micro evolution requires a loss of genetic code over time, and Macro requires the opposite. Errors and losses of genetic code are evidence for micro evolution, which is a documented scientific fact.
"Wow, you just totally changed the premise of your argument, nice goal post shift. The most commonly posited explanation for this is that life arose in the oceans, where a depth of ~30 metres would reduce the radiative effects to equivalent to those of the modern day."
Okay, but now you still have no oxygen to allow for any sort of chemical reaction...unless you're saying that the reaction would take place completely underwater??
"Not really, you claimed that no chemical reactions to produce ribonucleic acids existed that didn't require enzymes."
Still not clear enough yet hey?
Phosphate must have been, or must now come to have been, present at reasonable concentrations. (The concentrations in the oceans would have been very low, so we must think about special situationsevaporating lagoons and such. THEN, the phosphate must be activated in some wayfor example as a linear or cyclic polyphosphateso that phosphorylation of the nucleoside is possible.
Now, since your chemical reaction is occuring underwater, now we have to consider other parameters, such as Ph levels, temperatures, etc. The reaction would have needed to take place outside harmful sunlight radiation.
Either way, no life. As I said before. You need phosphate, that would not have been present, and you need oxygen, which may or may not have been, either way, you have no life.

This message is a reply to:
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Replies to this message:
 Message 117 by crashfrog, posted 08-21-2010 2:28 AM dennis780 has not replied
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