ILoveQuestions

"Simple deduction from my premises, really. I believe the world used to be perfect. This includes genes."

In other words, this is your personal belief. It is not even found in the bible. Why then are you presenting it as facts?

"When the Bible was written, people had no clue about genes"

LoL, yes! I completely agree. That's exactly why it's never mentioned in any religious scriptures.

"there would be NO reason for God to explain why... His audience would've been instantly lost."

Really? So you're saying god couldn't get them to understand if he wanted to? We have the same brain as then, we were not unteachable back then. If god would just have educated them a bit, they would have learned quickly.

Leviticus 15:13?
Lets back it up a bit, to... let's go to Leviticus 14:3. It's really funny to read...

"3 and the priest hath gone out unto the outside of the camp, and the priest hath seen, and lo, the plague of leprosy hath ceased from the leper,
4 and the priest hath commanded, and he hath taken for him who is to be cleansed, t̲w̲o̲ c̲l̲e̲a̲n̲ l̲i̲v̲i̲n̲g̲ b̲i̲r̲d̲s̲,̲ a̲n̲d̲ c̲e̲d̲a̲r̲ w̲o̲o̲d̲,̲ a̲n̲d̲ s̲c̲a̲r̲l̲e̲t̲,̲ a̲n̲d̲ h̲y̲s̲s̲o̲p̲.
5 `And the priest hath commanded, and he hath s̲l̲a̲u̲g̲h̲t̲e̲r̲e̲d̲ t̲h̲e̲ o̲n̲e̲ b̲i̲r̲d̲ upon an earthen vessel, o̲v̲e̲r̲ r̲u̲n̲n̲i̲n̲g̲ w̲a̲t̲e̲r̲;
6 [as to] the living bird, he taketh it, and the cedar wood, and the scarlet, and the hyssop, and hath d̲i̲p̲p̲e̲d̲ t̲h̲e̲m̲ a̲n̲d̲ ̲t̲h̲e̲ l̲i̲v̲i̲n̲g̲ b̲i̲r̲d̲ i̲n̲ t̲h̲e̲ b̲l̲o̲o̲d̲ o̲f̲ t̲h̲e̲ s̲l̲a̲u̲g̲h̲t̲e̲r̲e̲d̲ b̲i̲r̲d̲, over the running water,
7 and he hath s̲p̲r̲i̲n̲k̲l̲e̲d̲ o̲n̲ h̲i̲m̲ w̲h̲o̲ i̲s̲ t̲o̲ b̲e̲ c̲l̲e̲a̲n̲s̲e̲d̲ from the leprosy s̲e̲v̲e̲n̲ t̲i̲m̲e̲s̲, and hath pronounced him clean, and hath sent out the living bird on the face of the field."

"10 `And on the eighth day he taketh t̲w̲o̲ l̲a̲m̲b̲s̲, perfect ones, and o̲n̲e̲ e̲w̲e̲-̲l̲a̲m̲b̲, daughter of a year, a perfect one, and t̲h̲r̲e̲e̲ t̲e̲n̲t̲h̲ d̲e̲a̲l̲s̲ o̲f̲ f̲l̲o̲u̲r̲ [for] a present, mixed with oil, and one log of oil.
11 `And the priest who is cleansing hath caused the man who is to be cleansed to stand with them before Jehovah, at the opening of the tent of meeting,
12 and the priest hath taken the one he-lamb, and hath brought it near for a guilt-offering, also the log of oil, and hath waved them -- a wave offering before Jehovah.
13 `And he hath s̲l̲a̲u̲g̲h̲t̲e̲r̲e̲d̲ t̲h̲e̲ l̲a̲m̲b̲ in the place where he slaughtereth the sin-offering and the burnt-offering, in the holy place; for like the sin-offering the guilt-offering is to the priest; it [is] most holy.
14 `And the priest hath t̲a̲k̲e̲n̲ o̲f̲ t̲h̲e̲ b̲l̲o̲o̲d̲ of the guilt-offering, and the priest hath put o̲n̲ t̲h̲e̲ t̲i̲p̲ o̲f̲ t̲h̲e̲ r̲i̲g̲h̲t̲ e̲a̲r̲ of him who is to be cleansed, and o̲n̲ t̲h̲e̲ t̲h̲u̲m̲b̲ o̲f̲ h̲i̲s̲ r̲i̲g̲h̲t̲ h̲a̲n̲d̲, and o̲n̲ t̲h̲e̲ g̲r̲e̲a̲t̲ t̲o̲e̲ o̲f̲ h̲i̲s̲ r̲i̲g̲h̲t̲ f̲o̲o̲t̲;
15 and the priest hath taken of the log of oil, and hath poured on the left palm of the priest,
16 and the priest hath dipped his right finger in the oil which [is] on his left palm, and hath s̲p̲r̲i̲n̲k̲l̲e̲d̲ o̲f̲ t̲h̲e̲ o̲i̲l̲ w̲i̲t̲h̲ h̲i̲s̲ f̲i̲n̲g̲e̲r̲ s̲e̲v̲e̲n̲ t̲i̲m̲e̲s̲ b̲e̲f̲o̲r̲e̲ J̲e̲h̲o̲v̲a̲h̲.
17 `And of the residue of the oil which [is] on his palm, the priest putteth o̲n̲ t̲h̲e̲ t̲i̲p̲ o̲f̲ t̲h̲e̲ r̲i̲g̲h̲t̲ e̲a̲r̲ of him who is to be cleansed, and on the t̲h̲u̲m̲b̲ o̲f̲ h̲i̲s̲ r̲i̲g̲h̲t̲ h̲a̲n̲d̲, and on t̲h̲e̲ g̲r̲e̲a̲t̲ t̲o̲e̲ o̲f̲ h̲i̲s̲ r̲i̲g̲h̲t̲ f̲o̲o̲t̲, on the blood of the guilt-offering;
18 and the remnant of the oil which [is] on the palm of the priest, he putteth on the head of him who is to be cleansed, and the priest hath made atonement for him before Jehovah."

And then some more offerings, like pidgeons n' stuff. Then they clean a house, much in the same way.
The part you recommended, Leviticus 15:13:

"13 `And when he who hath the issue is clean from his issue, then he hath numbered to himself seven days for his cleansing, and hath washed his garments, and hath bathed his flesh with running water, and been clean.
14 `And on the eighth day he taketh to himself t̲w̲o̲ t̲u̲r̲t̲l̲e̲-̲d̲o̲v̲e̲s̲, or t̲w̲o̲ y̲o̲u̲n̲g̲ p̲i̲g̲e̲o̲n̲s̲, and hath come in before Jehovah unto the opening of the tent of meeting, and hath given them unto the priest;
15 and the priest hath made them, o̲n̲e̲ a̲ s̲i̲n̲-̲o̲f̲f̲e̲r̲i̲n̲g̲,̲ a̲n̲d̲ t̲h̲e̲ o̲n̲e̲ a̲ b̲u̲r̲n̲t̲-̲o̲f̲f̲e̲r̲i̲n̲g̲; and the priest hath made atonement for him before Jehovah, because of his issue."

These divine tips are just what you would expect if they were made up by superstitious bronze age people, stupid nonsense like offerings and splashing of blood 7 times, mixed with some better ideas.
It's not hard to think that they would have eventually noticed that washing and then making them go and live alone for 7 days, to be a good idea. If they came back and didn't have the sickness, it was Okay.

This is however NOT the kind of remedy you would expect the omniscient creator of the universe, would give to his people.

"If not than someone else was also there other than adam and eve to bring wives for abel and cain."

The Jewish text never says that adam and eve were the first humans, but the first humans in the garden created by a god.
At least that is what the Hebrew text is saying. The hebrew text takes in consideration, multiple gods and even a phanteon of gods with it's leader as the Elion.
Yeah the christian bible turned it in an epic of creation, but the Jewish text are not saying that.
The Jewish text took the story from Sumerian legends and gave it a Jewish twist.
Abraham was a Sumerian and he kept the Sumerian legends in the Jewish origins through his generations.

Evolution= fact (we can observe Micro evolution)
Human Micro evolution= fact (we can observe it in bacteria)
Human evolution from a Miocene ape= hypothesis (trying to explain our existence through evolution but not enough evidence has been presented yet)

It has not been proven yet that human descended from Miocene apes, neither enough evidence was ever presented for that case.
Actually there is contradictory evidence to that hypothesis, like genetic differences and huge physical difference.

We still do not know how we came to be on this planet yet, and it is OK to say that we do not know.

This has nothing to do with creation since the Admm and eve story is just a story and historians know that it is a twist on Sumerian myths.
So creationists still haven't really presented a case about how we were created.

Do not fall for the trap of answering a question about our existence that you do not have to.
At least let them present a case first.

This is like making such a stupid claim:
"You do not know what created a black hole therefore god exists."
You do not need to know what created a black hole to reject that unsupported claim.