Could climate affect Aisha's age of sexual maturity?

Question

Critics of Islam state that Muhammad had sex with Aisha bint Abu Bakr when she was nine years old, and that this was sexual abuse.

One defense made against the claim is that women become sexually mature earlier in hot climates like arabia than in cooler climates like northern Europe:

5- Medical & Scientific opinion about Aisha’s age for marriage:

a-Classic Encyclopedia states that: Puberty in hot climate areas is much earlier & faster than that in cold ones. So girls puberty age could reach 8 or 9 years in hot climate areas.

As stated by “Classic Encyclopedia”: [Encyclopedia Britannica, 1911 edition]

“In northern countries males enter upon sexual maturity between the age of fourteen and sixteen, sometimes not much before the eighteenth year, females between twelve and fourteen. In tropical climates puberty is much earlier.”

http://www.1911encyclopedia.org/Puberty

Is there any scientific evidence to back up this claim?

(This isn't the only defense made against the claim - other Muslims claim that Aisha wasn't nine when Muhammad had sex with her)

Answer 1

And this is still two separate questions, but I'll make an attempt to answer one of them. Or maybe a half. Namely "did Muhammad have sex with Aisha when she was nine years old". And the answer to that is as far as we can ascertain, a big question mark. We simply don't know.

The sources on Aisha is the Hadith, which are texts collected about Muhammad about a 100 or 200 years after his death. We don't know how accurate they are, but they are generally seen to be quite trustworthy, but they are at best second-hand accounts.

These sources (1, 2, 3, 4,) agree on that Muhammad and Aisha was engaged when she was 6 years old. But they can be separated according to who is the original source. Many of them attribute themselves to Aisha herself. She consistently says that she moved into Muhammad's household at the age of 9. No quote attributed to her says that the marriage was consummated at that (or any other) time.

Other quotes do say that is was consummated when she was nine. But the question then is how they know? Reasonably only Muhammad and Aisha knew. And the question also arises to what "consummated" means. In western tradition the marriage is consummated when you have intercourse. I can't find any source that says what word is used in the Arabic originals, so I don't know if the implications are the same.

Also, Aisha never had any children. But she used her position as Muhammads wife to wield power after his death, claiming to be his favorite wife in some of the quotes above. With her youth combined with the fact that she had no children, it might have been that people claimed that their marriage had never been consummated in an effort to minimize her influence. In that case of course other trustworthy people would have to step up and say that it was consummated. And since the culture at this time had no qualms about marriages to children, they didn't claim that it was consummated when she was 18 (at which point Muhammad was dying anyway) but more realistically that it was consummated when she joined Muhammad's household. And today people then go "Ugh, child molester!" as a result.

But in the end, the only sources we have are third-hand sources saying that the marriage was consummated when she was nine, although we don't know exactly what that means, and we can't be sure what happened, because only Aisha and Muhammad knew for sure, and they didn't say.

Answer 2

Several hadith state that Aisha was 6 when she married and 9 when the marriage was consumated. These hadith are narrated by Aisha herself and are considered strong hadith:

Bukhari vol. 7, #65: "Narrated Aisha that the prophet wrote the marriage contract with her when she was six years old and he consummated his marriage when she was nine years old."

Sunan of Abu Dawud, volume 2, #2116"Aisha said, "The Apostle of Allah married me when I was six years old. He had intercourse with me when I was 9 years old."

There are others.

Also, the hadith state that Aisha was still playing with dolls when she moved in with Muhammed. According to this Islamic scholor, that would not be allowed if Aisha had her first menses:

"Al-Khattaabee said: From this Hadeeth it is understood that playing with dolls (al-banaat) is not like the amusement from other images (suwar) concerning which the threat (wa'eed) of punishment is mentioned. The only reason why permission in this was given to 'Aa'isha (may Allah be pleased with her) is because SHE HAD NOT, AT THAT TIME, REACHED THE AGE OF PUBERTY." Source: The Beneficial Response Concerning the Islamic Ruling of Pictures/Images by: Shaykh Abdul-Azeez Ibn Abdullah Ibn Baaz

A further reading of the hadiths narrated by Aisha show a child that was still swinging withher playmates and playing with her dolls moving, as a wife, into muhammed's house when she was 9 and having sex with Muhammed at that time.

Bukhari, volume 5, #234

Sahih Muslim, Book 008, Number 3311

Sahih Muslim, Book 031, Number 5981

Sunan Abu Dawud, Book 41, Number 4914

"The History of Tabari", volume 9, page 131

Encyclopedia of Islam, under "Aisha"

As to the question of climate, the main factors that influence start of menses seem to be home environment and nutrition. For example, the worse the nutrition, the older the onset of menses. Climate does not seem to be a factor. For girls in Bagdad the average age of first menses is 13.6. For girls in The Netherlands it is 13.3.

http://www.mum.org/menarage.htm

I have not done extensive research on this topic, but whenever I have asked a Muslim for evidence of this popular claim I get nothing at all.