What is the origin of the male and female sex in evolution?

Genesis

What is the origin of the male and female sex in evolution?

- The XX chromosome mutated to an XY chromosome.

We are taught in school that evolution is a scientific fact.

- It is more proven than gravity.

However, I keep stumbling on questions that I can't answer.

- That is called "the process of science".

Almost all complex forms of life have male and female species (humans, fish, elephants, birds, etc.)

- There are some that are exclusively female, but in general you are right.

and the female needs the male to reproduce.

- No, parthenogenesis is a proven process.

If evolution is true, which one came first?

- The female and then eventually the mutation and then a male.

If the male evolved first,

- It didn't.

or the other way around?

- Like I said, there are animals that are exclusively female.

How can two different creatures evolve into humans and so may other mammals at the same time with different reproductive organs?

- Evolution.

In the Bible it obviously says that God made man and female at the same time.

- The bible also says that donkeys, snakes and bushes can talk.

I don't get it.

- Try thinking.

And where is the scientific evidence for that? Do you have a link?

- It is there, do your own research.

Neither came first. The first sexual reproduction was likely two gametes of the same size. The reason sexual reproduction evolved was because it was much more evolutionarily efficient. It is basically a more efficient way to disperse good genes throughout an entire population. An example that explains why is how bacteria do it. They have only one main chromosome so all the traits basically need to happen to each lineage since the chromosomes can't normally exchange DNA. It is built into sexual reproduction with something called crossing over where the chromosomes regularly exchange genes. You can therefore get all the good genes from an entire population. That is a huge advantage from an evolutionary efficiency point of view. Why males and females evolved is a bit more murky.

The best explanation I have heard is that there are two different basic strategies. One is spread you genes as far as possible and the other is to devote as much energy to each offspring as possible. Males can produce vastly more gametes or sperm and females can still devote much greater energy to each offspring. Having the males allows the genetic material to be rapidly dispersed and females allow eggs and offspring to be better equipped for survival. There are still two strategy among organisms, those that have lots of young with hope that some will survive and those that put even more energy into their offspring so each one has a greater chance. It is the same basic reason males and females probably arose in the first place. It isn't universal but it sure is common. It is the way plants and animals reproduce. It isn't the same with fungus however. They normally have what is considered very many sexes rather than just 2.

You clearly don't have a grasp on evolution..and I suspect that you are still adhering to the silly notion of Biblical mythology without admitting it...am I right !..??..Evolution means that there was NEVER a first..never a first human, never a first male, never a first female..think of it like an accent..the founding fathers had a British accent, now there is an unmistakable distinct American accent...but did anyone ever wake up one fine morning with the very first American accent..No..because accents EVOLVE over time..

I haven't looked into this but gender probably originated in plants. Think of pollen and the ovary in a plant.