(February 12, 2013 at 5:57 pm)Phish Wrote: Just a question to christians how is this logical again? Whats your argument?

My thoughts are in post 1
http://atheistforums.org/thread-14190.html

(February 13, 2013 at 10:52 am)festive1 Wrote: Well, you see, when humans first evolved, there was more than one species. Higher forms of life, birds, reptiles, mammals, all tend to reproduce sexually rather than asexually. I'm sure there may be exceptions, my biology knowledge base isn't wide enough to point them out, but asexual reproduction tends to happen in lifeforms like bacteria and worms. I'm not asserting that early humans reproduced asexually. They reproduced sexually, and did so with other species.

You're dodging. I'm asking about the first creatures to reproduce sexually. How did they get around the inbreeding problem?

Quote:Where's your evidence that Adam and Eve had perfect DNA, incorruptible from inbreeding?

I've already conceded that I don't have it. Where's your explanation regarding the first sexually reproducing creatures and the inbreeding problem, and your proof of that explanation?

The first creatures to develop sexual reproduction were not as complex as a human being. The more basic the organism, the less there is to fuck up. There's no proof that I am aware of... yet... See, that's the joy of science, it keeps advancing and incorporating new information as it becomes available. Perhaps the origins of sexual reproduction will never become available, as we are likely talking of microscopic forms of life that existed millions of years ago. It's still better than your theory that two perfect people populated the world.

---

This was bugging me, but a quick google search brought this up:

Quote:Many organisms can reproduce sexually as well as asexually. Aphids, slime molds, sea anemones, some species of starfish (by fragmentation), and many plants are examples. When environmental factors are favorable, asexual reproduction is employed to exploit suitable conditions for survival such as an abundant food supply, adequate shelter, favorable climate, disease, optimum pH or a proper mix of other lifestyle requirements. Populations of these organisms increase exponentially via asexual reproductive strategies to take full advantage of the rich supply resources.
When food sources have been depleted, the climate becomes hostile, or individual survival is jeopardized by some other adverse change in living conditions, these organisms switch to sexual forms of reproduction. Sexual reproduction ensures a mixing of the gene pool of the species. The variations found in offspring of sexual reproduction allow some individuals to be better suited for survival and provide a mechanism for selective adaptation to occur. The meiosis stage of the sexual cycle also allows especially effective repair of DNA damages (see Meiosis and Bernstein et al.[11]). In addition, sexual reproduction usually results in the formation of a life stage that is able to endure the conditions that threaten the offspring of an asexual parent. Thus, seeds, spores, eggs, pupae, cysts or other "over-wintering" stages of sexual reproduction ensure the survival during unfavorable times and the organism can "wait out" adverse situations until a swing back to suitability occurs.

Seems like a probable link to me... organisms that can reproduce both sexually and asexually as needed, handy. Sexual reproduction is great for diversity. Asexual reproduction is better for population numbers.
http://en.wikipedia.org/wiki/Reproduction

(February 13, 2013 at 1:18 pm)John V Wrote: You're dodging. I'm asking about the first creatures to reproduce sexually. How did they get around the inbreeding problem?

Possibly, they didn't, and we had several generations of inbred progenitors until enough variation resulted for it not to be an issue anymore. Inbreeding is not ideal, but it doesn't make propagation impossible.

(February 13, 2013 at 3:02 pm)Ryantology Wrote: Possibly, they didn't, and we had several generations of inbred progenitors until enough variation resulted for it not to be an issue anymore. Inbreeding is not ideal, but it doesn't make propagation impossible.

Actually I was going to bring that point up myself but wanted to do a little research first (which I still haven't done). In-breeding could be a non-issue for both sides.

---

(February 13, 2013 at 2:03 pm)festive1 Wrote: The first creatures to develop sexual reproduction were not as complex as a human being. The more basic the organism, the less there is to fuck up.

I could say that the fewer components to fuck up, the more vital each component is. You need to prove this point.

Quote:There's no proof that I am aware of... yet... See, that's the joy of science, it keeps advancing and incorporating new information as it becomes available. Perhaps the origins of sexual reproduction will never become available, as we are likely talking of microscopic forms of life that existed millions of years ago.

I don't have a problem with believing something without proof. That was Esquilax IIRC.

Quote:It's still better than your theory that two perfect people populated the world.

Your opinion is noted.

Quote:Seems like a probable link to me... organisms that can reproduce both sexually and asexually as needed, handy. Sexual reproduction is great for diversity. Asexual reproduction is better for population numbers.
http://en.wikipedia.org/wiki/Reproduction

Sometimes people try to go through this route to get from asexual to sexual, but it doesn't work. As you note, such creatures are better off than creatures who only reproduce sexually, so their would be no advantage to them in losing the asexual component.

The gene pool wouldn't really be...it wouldn't really be rich.

(February 13, 2013 at 3:15 pm)John V Wrote: Sometimes people try to go through this route to get from asexual to sexual, but it doesn't work. As you note, such creatures are better off than creatures who only reproduce sexually, so their would be no advantage to them in losing the asexual component.

Diversity is the advantage. Perhaps it outweighs the ability to create a million photocopies of oneself.

(February 13, 2013 at 4:25 pm)festive1 Wrote: Diversity is the advantage. Perhaps it outweighs the ability to create a million photocopies of oneself.

We're speaking here of creatures which can reproduce sexually or asexually. They already have diversity when possible, but photocopying when necessary. It's the best of both worlds, and there's no advantage in giving up the asexual backup.

The Red Queen hypothesis suggests that the major benefit to sexual reproduction is that it allows for much more reliable diversity, which is helpful in fighting off disease and parasites.

Quote:In Looking Glass Land, the Queen tells Alice, "It takes all the running you can do, to keep in the same place." According to the Red Queen hypothesis, sexual reproduction persists because it enables many species to rapidly evolve new genetic defenses against parasites that attempt to live off them.

Scientists from Rutgers University in New Jersey have tested this idea by observing different groups of small fish called topminnow in Mexico. Some populations of the topminnow reproduce sexually, while others reproduce asexually, so they provide the perfect opportunity to test these ideas. The topminnow is under constant attack by a parasite, a worm that causes something called black-spot disease.

The researchers found that identical populations ("clones") of the asexually reproducing topminnows harbored many more black-spot worms than did those producing sexually, a finding that fit the Red Queen hypothesis: The sexual topminnows could devise new defenses faster by recombination than the asexually producing clones.

(February 13, 2013 at 5:10 pm)Ryantology Wrote: The Red Queen hypothesis suggests that the major benefit to sexual reproduction is that it allows for much more reliable diversity, which is helpful in fighting off disease and parasites.

Yes, this has been the main explanation for the maintenance of sexual reproduction and to my knowledge isn't contested. However, it does not explain the origin of sexual reproduction.