(November 4, 2014 at 6:34 pm)Parkers Tan Wrote:

(November 4, 2014 at 6:14 pm)Reader Wrote: Why do we only have two genders, male and female? [excluding asexual animal reproduction] ... just humans and almost all animals? Why only two? Why not ... say ... seven, or seven-thousand? If we have evolved over time from a single celled organism ... why did we only evolve into two genders and not more? Why did it stop at two? Thanks for your time.

It's easier to code for two genders than three or four, and the genetic recombination from two genders is sufficient to produce a broad array of varieties.
Also, you have a familiar style. Have you posted here or on other atheist forums before?

Thanks for your reply. No, I am new here, have not posted here or in any other atheist forum before.

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(November 4, 2014 at 6:40 pm)Beccs Wrote:

(November 4, 2014 at 6:28 pm)Reader Wrote: Thanks, Beccs! I call it atheistic, because God is taken out of the equation. But the question is ... why did we stop evolving after two genders? Why don't we have more now? Like 7 or 7,000 or something along those lines?

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Because two genders are all we need. If more were required we would have evolved that way.

Thanks for that insight. What about the "transgender community" ... does it require a new gender? Or will male/female just have to work for them as is? I'm just thinking out loud here.

The only advantage I can see in having 7 (or 7000) genders, is that it would vastly increase your chance of a date for Saturday night. I can't see any realistic biological advantage.

Boru

(November 4, 2014 at 6:14 pm)Reader Wrote: I teach worldviews classes to high schoolers. We cover Secularism, Postmodernism, Islam, New Spirituality, Christianity and Marxism

Not to nitpick, but Islam, New Spirituality, Christianity are not serious worldviews, they are at best worldview wannabes, IMO nothing more then any other monotheistic religions where God used his magic and puffed the world into existance.

Once Upon The Time is not a worldview.

From Wikipedia:

Quote:Secularism is the principle of the separation of government institutions and persons mandated to represent the state from religious institutions and religious dignitaries.

So, Secularism is not a worldview.

Postmodernism is a 20th-century movement in the arts, it could be a worldview when one is on mescaline, but that's a subject for other occasion

Spot on with Marxism, it is a worldview, so if you are into worldviews you should just teach that

(November 4, 2014 at 6:14 pm)Reader Wrote: Greetings!

I'm new here, so I'll add a short reason why I am asking this question on this forum.

I teach worldviews classes to high schoolers. We cover Secularism, Postmodernism, Islam, New Spirituality, Christianity and Marxism. Within each worldview we cover each discipline of theology, philosophy, history, economics, sociology, ethics, biology, psychology, law and politics and how they differ across the board.

We are currently in the biology unit ... and I've pondered this question from an atheistic evolutionary viewpoint for a bit ... and I can't seem to find an answer.

Not atheistic, scientific or naturalistic.

Quote:So, I thought I would post here to see if you all could offer some insight.

Why do we only have two genders, male and female? [excluding asexual animal reproduction] ... just humans and almost all animals? Why only two? Why not ... say ... seven, or seven-thousand? If we have evolved over time from a single celled organism ... why did we only evolve into two genders and not more? Why did it stop at two? Thanks for your time.

Two sexes, some number of genders.

There are two general reasons. One is the structure of DNA - it is a double helix. It splits in half (meiosis) to create two complementary strands. This structure preceded sexual reproduction. Sexual reproduction evolved from that base.

The other is a mathematical proof of the optimality of two sexes. I would have to dig up a reference. Or you could.

(November 4, 2014 at 6:14 pm)Reader Wrote: Why do we only have two genders, male and female? [excluding asexual animal reproduction] ... just humans and almost all animals? Why only two? Why not ... say ... seven, or seven-thousand? If we have evolved over time from a single celled organism ... why did we only evolve into two genders and not more? Why did it stop at two? Thanks for your time.

You have to think about it as an optimization problem.

Sexual reproduction allows for greater variability -> higher likelihood to produce an advantages trait.

The minimum requirement for sexual reproduction is 2 sources. Once you start require more, you reduce your likelihood of finding 3, 4, 5, ... mates to produce 1 offspring.

(November 4, 2014 at 7:53 pm)FifthElement Wrote:

(November 4, 2014 at 6:14 pm)Reader Wrote: I teach worldviews classes to high schoolers. We cover Secularism, Postmodernism, Islam, New Spirituality, Christianity and Marxism

Not to nitpick, but Islam, New Spirituality, Christianity are not serious worldviews, they are at best worldview wannabes, IMO nothing more then any other monotheistic religions where God used his magic and puffed the world into existance.

Once Upon The Time is not a worldview.

From Wikipedia:

Quote:Secularism is the principle of the separation of government institutions and persons mandated to represent the state from religious institutions and religious dignitaries.

So, Secularism is not a worldview.

Postmodernism is a 20th-century movement in the arts, it could be a worldview when one is on mescaline, but that's a subject for other occasion

Spot on with Marxism, it is a worldview, so if you are into worldviews you should just teach that

Worldview ... everybody has one. It's how one "views" the world. Secularist, Marxism, Islam, New Spiritualist, Postmodern, Christianity are the dominant ones in our culture today. You can say it's like a pair of glasses we all look through. In other words, the pattern of ideas, beliefs, convictions, and habits that help us make sense of the world around us, and our relationship to this world.

I remember reading an article a while back about a type of ant colony with a queen that needed to mate with a certain type of male to produce queens for future colonies, and another type of male to produce worker ants. This doesn't exactly translate to 3 separate sexes needed to produce 1 offspring, but you can maybe say 3 parents for 1 colony. It's also easy to see how this mating method wouldn't effect the odds of finding the right mate under the stricter criteria, since there is just the 1 easily located queen as the target. She's more like the egg with the males being the sperm.

(November 4, 2014 at 8:27 pm)Reader Wrote:

(November 4, 2014 at 7:53 pm)FifthElement Wrote: Not to nitpick, but Islam, New Spirituality, Christianity are not serious worldviews, they are at best worldview wannabes, IMO nothing more then any other monotheistic religions where God used his magic and puffed the world into existance.

Once Upon The Time is not a worldview.

From Wikipedia:


So, Secularism is not a worldview.

Postmodernism is a 20th-century movement in the arts, it could be a worldview when one is on mescaline, but that's a subject for other occasion

Spot on with Marxism, it is a worldview, so if you are into worldviews you should just teach that

Worldview ... everybody has one. It's how one "views" the world. Secularist, Marxism, Islam, New Spiritualist, Postmodern, Christianity are the dominant ones in our culture today. You can say it's like a pair of glasses we all look through. In other words, the pattern of ideas, beliefs, convictions, and habits that help us make sense of the world around us, and our relationship to this world.

Strictly speaking, secularism is only part of a comprehensive worldview.

(November 4, 2014 at 8:01 pm)Chas Wrote:

(November 4, 2014 at 6:14 pm)Reader Wrote: Greetings!

I'm new here, so I'll add a short reason why I am asking this question on this forum.

I teach worldviews classes to high schoolers. We cover Secularism, Postmodernism, Islam, New Spirituality, Christianity and Marxism. Within each worldview we cover each discipline of theology, philosophy, history, economics, sociology, ethics, biology, psychology, law and politics and how they differ across the board.

We are currently in the biology unit ... and I've pondered this question from an atheistic evolutionary viewpoint for a bit ... and I can't seem to find an answer.

Not atheistic, scientific or naturalistic.

Quote:So, I thought I would post here to see if you all could offer some insight.

Why do we only have two genders, male and female? [excluding asexual animal reproduction] ... just humans and almost all animals? Why only two? Why not ... say ... seven, or seven-thousand? If we have evolved over time from a single celled organism ... why did we only evolve into two genders and not more? Why did it stop at two? Thanks for your time.

Two sexes, some number of genders.

There are two general reasons. One is the structure of DNA - it is a double helix. It splits in half (meiosis) to create two complementary strands. This structure preceded sexual reproduction. Sexual reproduction evolved from that base.

The other is a mathematical proof of the optimality of two sexes. I would have to dig up a reference. Or you could.

Thanks for your insight as well. Again, just looking for understanding on the two genders [sexes] we have now ... how did we go from one "sex", say male for example, to having two sexes? Did we start off with two, or did one evolve from one into two?

Reader, this represents the most common misunderstanding of evolution that comes from theists. (Not saying you are a theist, just saying that they bring this up too often.)

Evolution does not necessitate that everything trend towards infinity. What I mean by this is that if an organism is perfectly suited to it's environment, then we wouldn't expect any genetic drift. Obviously no organism is perfectly suited to its environment, so there is always space to improve in some areas. However, if a certain aspect of anatomy or physiology functions very well, then there is very little selection pressure. So even if a new gender were to have mutated, it would have very likely been ousted very quickly, as the likelihood that a single new gender would be able to reproduce would be pretty low. In fact, two new genders would likely have had to mutate pretty early in the evolutionary process at the same time within the same population in order for them to have been sexually selected.

Two genders is all that is needed. And if things had gone differently very early on, I might be saying "six genders is all that is needed."