Edit: see post #2 if this one is confusing.

I don't know if this has this been discussed here and I also don't know how
exactly to formulate this question correctly. Anyway..


In my understanding, according to evolution theory, we are all evolved from
simpler life form. But how does sex differentiation between male and female
developed? Why today in almost all kind of species (except hermaphrodite
or asexual type), for every male species there is the female species?


Let say the evolution path was like this:

species A ---> species B ----> ................. ----> human

Each species consist of male and female. In which stage did the male and
female differentiation developed?

Assuming the male exist earlier before the female, was it like this (scenario 1):


----------------------------------------------------------------------

Note: you can skip this first scenario if this is confusing.

male A ---> female A, male B (male of species B evolved from male of species A; female of species A also evolved from male of species A)

male B ---> female B, male C

male C ---> female C, male D

etc until:

male XYZ ---> human male ---> human female

----------------------------------------------------------------------

Or was it like this (scenario 2):

male A ---> male B ---> male C ----> ................... human male
female A ---> female B ---> female C ----> ........... human female

:shrug:

My question could be also expressed in another way. Let say human came from ape
and the first human was male.

Then where does the female human came from? Was it evolve from male human, or from
female ape?

Let say female human evolve from male human. If I kill all female human,
will eventually female human evolve from male human? If so, how can that happen,
while to create the next male generation (and hence giving enough time for the
evolution to happen) that next male generation should be born first, and that would be
impossible without the presence of the female one?

Or was the first human asexual? hermaphrodite? :confused: What about all other species?
Does it all follow the SAME pattern? How come? Coincidental??

Human were never asexual or hermaphordite, in fact human ancestors went duel sexed ohh ~500 million years ago when they evolved just beyond worms. Duel sex or gonochorism is more stable then hermaphordism when mate selection can happen, the theory goes like this:

1. A male only mutant appears in a population of hermaphorditic organism by random mutation.
2. The male is able to spreed it genes faster then the hermaphordites because it waste less energy making progeny by only providing genes, the male variant soon outnumbers the hermaphordite varient
3. A lack of breedable partners for the males makes the hermaphrodites variant competitive viable again.
4. A female mutant appears and is more competitive then the hermaphrodite variant because it does not waste energy trying to be a male.
5. Eventually the hermaphrodite variant dies off.

Mathematica models simulate evolving populations show this to be true, that hermaphroditism is usually an unstable state in multiple cellular organism with mate selection, that these population usually fall into the more stable state of gonochorism.

I am not quite sure what you are asking. Before there was sexual reproduction there were of course no males or females.

I am not quite sure what you are asking. Before there was sexual reproduction there were of course no males or females.

Before I reply to post #4, I will firstly reply to this post (post #5).

Sorry for the confusion.

As I understand, evolution is a slow process, it took very long time until one
new species formed from another simpler form. Human species, for example,
who is said to be firstly appear in Africa about 200,000 years ago, till now
hasn't changed into a different species. Perhaps it doesn't evolve anymore.
Anyway according to evolution theory, it was evolved from something else; it
wasn't created by invisible hands.

There are at least 1.5 million species of living organism (that so far been named,
not to count the one that hasn't been named). In almost all kind of species,
there is a male and female couple. If one species evolved from another, how
come all these species has its pair? Coincidental? :confused:

That's why I asked, how was the chain of evolution which correspond to the
formation of the opposite sex. And as the example, I asked about the human
species.

We are consist of male and female, and we are evolved from something simpler.
As human male is simpler than human female (e.g. male can't produce baby), I
assume the human male existed first before the human female. But where
does the human female came from? If it was evolved from the male, I would
say it is impossible. Why?

Let say it took 1000 generation until one male can changed into female. But
the 2nd generation of male CAN'T be existed unless the 1st generation of male
can reproduce. The 3rd generation CAN'T be existed unless the 2nd one can
reproduce, etc. To create the next generation, there should be the opposite
sex in the first place. Right? Unless it was hermaphrodite.

And so I asked whether the first male were hermaphrodite.

If not, then the first female human must be evolved NOT from the male human,
but from the same previous ancestor (let say ape, the female one).

If that is true, then the chain of evolution was like this:

ALL male: species A ---> species B ----> species C ----> ............. ----> human male species

ALL female: species A ---> species B ----> species C ----> ............. ----> human female species

That doesn't make sense to me either as the female of each species more
closely resemble to its male species. Female human are much more alike with
male human then female ape, right? Female cat much more alike with male
cat then with other female species, right? And so on.

So, what do you think? :shrug:

Human were never asexual or hermaphordite, in fact human ancestors went duel sexed ohh ~500 million years ago when they evolved just beyond worms. Duel sex or gonochorism is more stable then hermaphordism when mate selection can happen, the theory goes like this:

1. A male only mutant appears in a population of hermaphorditic organism by random mutation.
2. The male is able to spreed it genes faster then the hermaphordites because it waste less energy making progeny by only providing genes, the male variant soon outnumbers the hermaphordite varient
3. A lack of breedable partners for the males makes the hermaphrodites variant competitive viable again.
4. A female mutant appears and is more competitive then the hermaphrodite variant because it does not waste energy trying to be a male.
5. Eventually the hermaphrodite variant dies off.

Mathematica models simulate evolving populations show this to be true, that hermaphroditism is usually an unstable state in multiple cellular organism with mate selection, that these population usually fall into the more stable state of gonochorism.


I understand step 1. Lets stop at step 2 first:

2. The male is able to spreed it genes faster then the hermaphordites because it waste less energy making progeny by only providing genes, the male variant soon outnumbers the hermaphordite varient

What do you mean by spread its genes? Spread where to? There was no
female one at this stage. When there is no female one, the male one can't
spread its genes :shrug:

Your scenario is only possible to happens if:

* The male and the female mutant appears at the same time
* The male and the female mutant appears at the same or nearby place (so that they can meet and reproduce).

And this happens to all others 1.5 million species? :confused:


Another question:

* how long does it take to form one species from another until it created all pairs of 1.5 million different species?
* with the age of earth, is that process possible?

I mean, is there any finding that explain about it??

Your scenario is only possible to happens if:

* The male and the female mutant appears at the same time
* The male and the female mutant appears at the same or nearby place (so that they can meet and reproduce). lol Theres your error, There where no sudden males or no sudden females, it was a very long gradual process.
Look at it this way,
There was a single celled organism that reproduced itself and over time became a two celled organism, etc.. eventually becoming a multi celled organism, as it adapted to it's environment, it was more efficient for it's survival, so it adapted to two sexes( this being over a very long time) from this change came every two sex species on this planet.
And this happens to all others 1.5 million species? :confused:lol, Well with that kind of mistake, you should be.
It didn't happen to all the species individually, all the species came from the original one.

lol Theres your error, There where no sudden males or no sudden females, it was a very long gradual process.
Look at it this way,
There was a single celled organism that reproduced itself and over time became a two celled organism, etc.. eventually becoming a multi celled organism, as it adapted to it's environment, it was more efficient for it's survival, so it adapted to two sexes( this being over a very long time) from this change came every two sex species on this planet.

I don't think so. In the whole kingdom of 1.8 million species, each species are
distinct. You can't miss one species with another. One species also can also
reproduce with each other in the same species. So how does each species
formed into pairs (male and female) in all 1.8 million species??

My question still also remain: where does the female human came from?
From male human or from female ancestor? Both doesn't make sense to me
(I explained the reason in the previous post).


lol, Well with that kind of mistake, you should be.
It didn't happen to all the species individually, all the species came from the original one.


So, from the whole existing 1.8 millions species, where does each opposite
sex came from? (p.s: age of earth is only around 4.5 billion years old). What
is the time scale of evolution of each species? Oldest human appears nearly
200,000 years ago. Until now it hasn't evolved into another species. What
about the cats? dogs? etc? They are still the same as well, don't they? :confused:

My point is, you said (and all other evolutionist always said) that it changes
gradually, in a very very long time.

Let say species A evolved gradually until it becomes something new after
100,000 years (there is 1.8 million distinct species). How can it evolve
without the presence of its opposite sex? How can its next generation with its
slight change existed without being born? Did its opposite sex came from itself
first? I don't think so. Female human can't evolved from male human, unless the
male human able to give birth to a new (female) human. I think it goes the same
for all other 1.8 million species.

You're not thinking about this the right way inzomnia. You expect some kind of sudden change which completely changes a species into another, making them unable to reproduce. It doesn't work like that. It's many small changes over a long time building on each other.

Think of two isolated groups of mice, both the same species. One evolves on an island completely cut off from the rest. Over millions of years both groups evolve differently, small changes building on each other. Eventually a mouse from group A can't reproduce anymore with a mouse from group B, but both groups can still reproduce within their own groups. At that point we say the mice have split into new species. There's no one change that suddenly creates a new species of mouse, it's a long gradual process.

You're not thinking about this the right way inzomnia. You expect some kind of sudden change which completely changes a species into another, making them unable to reproduce. It doesn't work like that. It's many small changes over a long time building on each other.

Think of two isolated groups of mice, both the same species. One evolves on an island completely cut off from the rest. Over millions of years both groups evolve differently, small changes building on each other. Eventually a mouse from group A can't reproduce anymore with a mouse from group B, but both groups can still reproduce within their own groups. At that point we say the mice have split into new species. There's no one change that suddenly creates a new species of mouse, it's a long gradual process.

That doesn't answer my question yet. Where does the opposite sex of each
species come from?

There is about 1.8 million of species out there, and each has its pairs (opposite sex).
How does evolution theory explain this? Can you give me a scenario?

It does answer your question. Forget everything you think you know about evolution and read it again. I can't help you understand the process if you're unwilling to let go of the wrong assumptions you've made about how it works.

There is about 1.8 million of species out there, and each has its pairs (opposite sex).
How does evolution theory explain this? Can you give me a scenario?

No it doesnt. No all species have both sexes. Again.. everything has being explained to you.. you simply are not understanding.

It does answer your question. Forget everything you think you know about evolution and read it again. I can't help you understand the process if you're unwilling to let go of the wrong assumptions you've made about how it works.

I am here to learn. So what is your answer to my question?


No it doesnt. No all species have both sexes. Again.. everything has being explained to you.. you simply are not understanding.

I did mention previously, there is an exception, such as in hermaphrodite or
asexual type. Those are exception. If you feel this is significant, can you
give me the number of the exception?

Look, Xelios, if you are able to explain me in a clear and logical way about how
does sex differentiation exist in evolution, I am willing to reconsider my opinion.

I am here to learn. So what is your answer to my question?
You're here to learn something you've previously learned wrong. That requires you to forget what you learned wrong, which you're not willing to do. You're holding onto it and consequently what we're telling you seems wrong to you. You can't learn anything if you keep doing that.

I'll make one more go through it.

Think of two isolated groups of mice, Group A and Group B, both the same species. Group A evolves on an island, comletely cut off from Group B. Over millions of years both groups evolve differently, small changes building on each other. Both males and females evolve together. Each time a new generation is produced the changes (if any) are present in BOTH, male and female, of that new generation. No single change is big enough to prevent the new generation from mating with other members of its group (this is the important part you're not getting), and if it is this new generation simply can't reproduce and dies out. The change dies with it.

Eventually (after millions of years) a mouse from group A can't reproduce anymore with a mouse from group B, but both groups can still reproduce within their own groups. At that point we say the mice have split into new species. There's no one change that suddenly creates a new species of mouse, it's a long gradual process.

inzommia:
( very appropriate name by the way. )

I'm sorry your just not getting it, you should return to class, you need evolution basic 101.
Here are a few sites that will educate you.

http://www.youtube.com/user/potholer54
http://www.youtube.com/profile_videos?user=potholer54&p=r

http://members.cox.net/sbcogan/evo-kids.html
http://www.leaderu.com/orgs/probe/docs/cr-evol.html
http://www.pbs.org/wgbh/evolution/humans/index.html
http://www.pbs.org/wgbh/nova/link/evolution.html#
http://www.talkorigins.org/

Once you better understand evolution, then you might return and ask questions,( but I don't think you will need too) until then I'd stay of evolution if I was you.

I did mention previously, there is an exception, such as in hermaphrodite or
asexual type. Those are exception. If you feel this is significant, can you
give me the number of the exception?

Hundreds and hundreds of thousands. Bacteria, virii, fungi and all other forms of life. You did do biology at school?

I understand step 1. Lets stop at step 2 first:

2. The male is able to spreed it genes faster then the hermaphordites because it waste less energy making progeny by only providing genes, the male variant soon outnumbers the hermaphordite varient

What do you mean by spread its genes? Spread where to? There was no
female one at this stage. When there is no female one, the male one can't
spread its genes :shrug:

hermophodites make do as females during stage 2, the males spreed their gene through the population, making more males then hermophodites.

You're here to learn something you've previously learned wrong. That requires you to forget what you learned wrong, which you're not willing to do. You're holding onto it and consequently what we're telling you seems wrong to you. You can't learn anything if you keep doing that.

I'll make one more go through it.

Think of two isolated groups of mice, Group A and Group B, both the same species. Group A evolves on an island, comletely cut off from Group B. Over millions of years both groups evolve differently, small changes building on each other. Both males and females evolve together. Each time a new generation is produced the changes (if any) are present in BOTH, male and female, of that new generation. No single change is big enough to prevent the new generation from mating with other members of its group (this is the important part you're not getting), and if it is this new generation simply can't reproduce and dies out. The change dies with it.

Eventually (after millions of years) a mouse from group A can't reproduce anymore with a mouse from group B, but both groups can still reproduce within their own groups. At that point we say the mice have split into new species. There's no one change that suddenly creates a new species of mouse, it's a long gradual process.


I don't want to jump into 2 isolated groups. Before we jump into 2 groups, lets
start from the beginning.

Lets assume that there is this first life form namely "A". What was A? A male?
A female? A hermaphrodite? Asexual?

Lets go from there.

inzommia:
( very appropriate name by the way. )


What do you mean? I live in Germany, local time is 1 PM (mid-day).


I'm sorry your just not getting it, you should return to class, you need evolution basic 101.
Here are a few sites that will educate you.

http://www.youtube.com/user/potholer54
http://www.youtube.com/profile_videos?user=potholer54&p=r

http://members.cox.net/sbcogan/evo-kids.html
http://www.leaderu.com/orgs/probe/docs/cr-evol.html
http://www.pbs.org/wgbh/evolution/humans/index.html
http://www.pbs.org/wgbh/nova/link/evolution.html#
http://www.talkorigins.org/

Once you better understand evolution, then you might return and ask questions,( but I don't think you will need too) until then I'd stay of evolution if I was you.


Will you answer my question? You can quote the link if you wish (in the explanation).

Hundreds and hundreds of thousands. Bacteria, virii, fungi and all other forms of life. You did do biology at school?

Ok, I did not have any idea that the number is hundred of thousands out of
million. Anyway, it hasn't answered my question yet. I'd like to know from where
each opposite sex in, say half the rest of species, came from? From where it
evolved?

hermophodites make do as females during stage 2, the males spreed their gene through the population, making more males then hermophodites.

You mean, the hermaphrodite can act as the female one?

I don't want to jump into 2 isolated groups. Before we jump into 2 groups, lets
start from the beginning.

Lets assume that there is this first life form namely "A". What was A? A male?
A female? A hermaphrodite? Asexual?

Lets go from there.

You can as well make the scenario for each possibility if you wish.

You mean, the hermaphrodite can act as the female one?

yeah, I would think the definition of hermaphrodite covers that.

I don't want to jump into 2 isolated groups. Before we jump into 2 groups, lets
start from the beginning.

Lets assume that there is this first life form namely "A". What was A? A male?
A female? A hermaphrodite? Asexual?

Lets go from there.
But you do understand that changes are gradual, and not sudden, right? Like there's no single change that turns an asexual organism into a sexual one with both male and female.

The very first was probably asexual, though that doesn't mean it was limited to asexual reproduction. Even bacteria (one of the oldest forms of life), which are asexual, can exchange genetic information between each other (google conjugation). Lots of plants exist that are both sexual and asexual, like normal lawn grass for example. It reproduces asexually locally but also produces seeds through sexual reproduction that travel to some other patch of dirt and start growing there. Hell even some female fish lay eggs that hatch into a new generation without ever being fertilized.

Like I said before, there's no definite line where all of a sudden you have males and females coming from an organism that before was asexual.

yeah, I would think the definition of hermaphrodite covers that.

This at least explain a missing link. I don't think a sexual species like human
can evolve without opposite sex. I also don't think it was always co-existed.
If evolution theory were true, there should be a start somewhere where one
evolved from another (in this case the hermaphrodite).

So, was this the scenario (arrow indicates evolution in a long time):

hermaphrodite A ----> male A (simple) ----> ......... -----> human male (complex)
hermaphrodite A ----> female A (simple) ----> ......... -----> human female (complex)


And on the other side (the formation of species B):

hermaphrodite A ----> hermaphrodite B ----> male B (simple) ----> ......... -----> male species B (complex)
hermaphrodite A ----> hermaphrodite B ----> female B (simple) ----> ......... -----> female species B (complex)

etc :confused:

Inzommi: http://www.sciencedaily.com/releases/2008/01/080109173726.htm

and for detailed reading, this will be useful:
http://en.wikipedia.org/wiki/Evolution_of_sex

Read the first link though!

But you do understand that changes are gradual, and not sudden, right? Like there's no single change that turns an asexual organism into a sexual one with both male and female.

The very first was probably asexual, though that doesn't mean it was limited to asexual reproduction. Even bacteria (one of the oldest forms of life), which are asexual, can exchange genetic information between each other (google conjugation). Lots of plants exist that are both sexual and asexual, like normal lawn grass for example. It reproduces asexually locally but also produces seeds through sexual reproduction that travel to some other patch of dirt and start growing there. Hell even some female fish lay eggs that hatch into a new generation without ever being fertilized.

Like I said before, there's no definite line where all of a sudden you have males and females coming from an organism that before was asexual.


I understand it is gradual, but when I thought that nearly all half species
existed on earth are couple, this made me thinking how did it evolve. It is
simpler to me had all had been created in the first place. Also that there is
at least 1.8 million types of species and just 4.5 billion years of age of earth.
If the evolution was a single chain, I will say it is impossible, because, assuming
the first life form was existed together with the earth, that leave only 2500
years for each species to evolve. If evolution is existed, it should have been
parallel, and the opposite sex evolved from its hermaphrodite. Weird, still...

Inzommi: http://www.sciencedaily.com/releases/2008/01/080109173726.htm

and for detailed reading, this will be useful:
http://en.wikipedia.org/wiki/Evolution_of_sex

Read the first link though!

I'll have a look. I have to go to college now, though. Ciao

I understand it is gradual, but when I thought that nearly all half species
existed on earth are couple, this made me thinking how did it evolve. It is
simpler to me had all had been created in the first place. Also that there is
at least 1.8 million types of species and just 4.5 billion years of age of earth.
If the evolution was a single chain, I will say it is impossible, because, assuming
the first life form was existed together with the earth, that leave only 2500
years for each species to evolve. If evolution is existed, it should have been
parallel, and the opposite sex evolved from its hermaphrodite. Weird, still...
Main point is there's a lot of intermediate steps between asexual and sexual reproduction. There are still organisms alive today that are neither asexual or sexual, but somewhere in between, or both.

Evolution is a tree, not a single chain. It all started at a common trunk, but branches off more and more as time goes on. Sexual reproduction evolved about 2.5 billion years ago, which means its near the start of the evolutionary tree. As a result, most branches share this trait even if they all evolved seperate of each other (parallel) in the time since then.

Where in Germany are you? I'm living near Dortmund right now.

This at least explain a missing link. I don't think a sexual species like human
can evolve without opposite sex. I also don't think it was always co-existed.
If evolution theory were true, there should be a start somewhere where one
evolved from another (in this case the hermaphrodite).

So, was this the scenario (arrow indicates evolution in a long time):

hermaphrodite A ----> male A (simple) ----> ......... -----> human male (complex)
hermaphrodite A ----> female A (simple) ----> ......... -----> human female (complex)


And on the other side (the formation of species B):

hermaphrodite A ----> hermaphrodite B ----> male B (simple) ----> ......... -----> male species B (complex)
hermaphrodite A ----> hermaphrodite B ----> female B (simple) ----> ......... -----> female species B (complex)

etc :confused:

I think your missing the mechanism of sex. It started simply with two cells coming in contact with each other and trading genetic information via a pilli or DNA pore of some kind, or simply two cells merged. When organisms went multiple celled a cell types specific to sex came about, evolution found it favorable to make two cell types, one for receiving genetic information and the other for delivering genetic information. At this time most organism would produce both cell types, but once organisms became advance enough to compete with one another for mating rights it became evolutionarily favorable for one organism to drop the other sexual cell type and become optimized in utilizing only one sexual cell type.

What do you mean? I live in Germany, local time is 1 PM (mid-day).It's called sarcasm, you seem to be in a dream state.Will you answer my question? You can quote the link if you wish (in the explanation).It has been answered you just cant comprehend it, hence why I said you need re-schooling.
Haven't you wondered why everybody is saying the same thing to you.

There are at least 1.5 million species of living organism (that so far been named,
not to count the one that hasn't been named). In almost all kind of species,
there is a male and female couple. If one species evolved from another, how
come all these species has its pair? Coincidental? :confused:

Original, rather. As someone was saying, sex has been around for maybe 500 million years. Even during the process of evolution, the sexes have remained the sexes - it might be best to say that sex has evolved with the non-sex chromosomes (autosomes).

Now, although we still have sexes, it is true that sex can be a motivator of speciation through the generation of hybrids and so forth. But in that case, it's more about the chromosomal mechanics and genetic polymorphism.

Probably, self-replicating organisms at one point began exchanging genetic material with others from the same species.
This proved to be beneficial because it increased genetic variety (the species becomes more hardy to change when genetic variety is large).
At some point preferences for particular traits arose, different sexes evolved.

The species probably retained the ability of asexual reproduction for a long time.
Eventually species differentiated that were exclusively sexual in reproduction, they lost the ability to asexually reproduce. This probably happened because of dense populations (no need to retain the ability to asexually reproduce).

I am just following a logical path here, correct me if you have evidence that says otherwise.

PS
To some people in this thread: speciation can occur really fast.

Main point is there's a lot of intermediate steps between asexual and sexual reproduction. There are still organisms alive today that are neither asexual or sexual, but somewhere in between, or both.

Evolution is a tree, not a single chain. It all started at a common trunk, but branches off more and more as time goes on. Sexual reproduction evolved about 2.5 billion years ago, which means its near the start of the evolutionary tree. As a result, most branches share this trait even if they all evolved seperate of each other (parallel) in the time since then.

Where in Germany are you? I'm living near Dortmund right now.


Thx for the explanation (also to others that have been participated so far).
I think I need some time to read more. Here is in Köln.

A species that could share genetic material would lead to a more robust species, since it would create more variation. Bacteria already share genetic information from time to time. I don't know the exact mechanism. This must have evolved very early on. If you don't have sexes, you only have clones of yourself, which could be easily wiped out by environmental change or disease.

A species that could share genetic material would lead to a more robust species, since it would create more variation. Bacteria already share genetic information from time to time. I don't know the exact mechanism. This must have evolved very early on. If you don't have sexes, you only have clones of yourself, which could be easily wiped out by environmental change or disease.

Exactly :)
See post 37, tell me what you think.

Oh yeah I didn't read that. Some species still do not reproduce sexually. There are some advantages to it.

Oh yeah I didn't read that. Some species still do not reproduce sexually. There are some advantages to it.

Yep, but most can if the opportunity arises, like the bacteria you mentioned.

Did sex arise independently in plants?

If everybody isn't reproducing there is more food to go around. Not everyone in a bee hive or a wolf pack gets to reproduce.

Did sex arise independently in plants?

It's the logical development. It's probably an eventuality in all organic development. Especially in higher life forms. One to care. One to hunt. One to nest. One to build.

~String

It's the logical development. It's probably an eventuality in all organic development. Especially in higher life forms. One to care. One to hunt. One to nest. One to build.

~String

Asexual reproduction is more logical, though less diverse.

Probably, self-replicating organisms at one point began exchanging genetic material with others from the same species.
.


Why only from the same species? What about exchanging genetic material from other species? Mitochondria would be a good example.

Did sex arise independently in plants?

IIRC the most sexual diversity I've run across personally was a species of fungus that had eight sexes. I don't think that's the record.

Fungi and algae can have some very complicated life cycles.

One big advantage of sex in large, long-lived organisms is disease resistance from the recombination. Just splitting is much more efficient from an energy budget and risk point of view, but then the kid's a clone - any disease that comes along after a while will have an easy concentration of identical targets.

Wow. A lot of stuff gets thrown around here. First one question IIRC the most sexual diversity I've run across personally was a species of fungus that had eight sexes.
Could you dig up where you found this? I would be really interested.

Now back to the OP. I gather that the basic question is directed at the evolution of sexual reproduction.


Let us take a step back. Asexual reproduction can be seen as the basic form in which each individual creates genetically identical (except for mutations) offspring. Sexual reproduction in contrast has a the classical two-fold cost compared to asexual reproduction. Also co-adapted traits may be broken up thus resulting in a loss in fitness.
Nonetheless sexual reproduction did evolve. There are a number of explanations why the evolution of sex may have resulted in fitness increases instead. But before I continue to elaborate on that I would like to know whether it is the correct course of the discussion after all....

If everybody isn't reproducing there is more food to go around. Not everyone in a bee hive or a wolf pack gets to reproduce.

You are right, but what is your point ?

Asexual reproduction is more logical, though less diverse.




Why only from the same species? What about exchanging genetic material from other species? Mitochondria would be a good example.

Hmm yes, most likely that happened as well. At one point same species sex became the norm however, I just picked up from there.