h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I'd be more worried about having a photo with really crappy hairdo taken today, than one taken 24 years ago when everyone had really crappy perms.

"Having a strange hair life? Blame your parents.

That's right, misbehaving hair may be inherited, according to a study released Monday.

Researchers studying mice determined that the aptly named gene Frizzled 6 controls hair patterns. Subjects without the gene had strange patterns, including whorls of hair on their hind feet, back of the head and chest. Some also had tufts and ridges in the hair on their head."

http://www.cnn.com/2004/HEALTH/05/24/bad.hair.gene.ap/index.html

I was skimming the article and missed the bit about "mice". Imagine my confusion when I came to the bit about "whorls of hair on their hind feet".

"Mirror" twins have whorls which go in opposite directions, one will be left-handed and the other right-handed.

According to what I have read, "mirror" or "identical" (ie; with identical not opposite traits) is determined by the point in gestation at which the egg actually splits into two foetuses.

This theory arose when it was determined that conjoined twins invariably

There are actually a number of different types of twins.

Identical (monozygotic): from one zygote (fertilized egg) that splits in two. 100% identical DNA

Fraternal (dizygotic): when the mother releases two eggs and both become fertilized. They can be the same or different sexes. 50% identical DNA

Mirror: Around 25% of twins have mirror image characteristics, which is related to when the egg split in two

Conjoined (Siamese): a type of Monoamniotic Monochorionic twins who failed to separate completely, perhaps because they split very late in development (12 days or later since conception). Most conjoined twins are also mirror twins.

Half Identical Twins (Polar body twinning): occurs when a egg splits prior to fertilization and each half receives a separate sperm. The twins share 75% of their DNA.

Twins of Two: Two eggs are released by the ovaries and each egg is fertilized by a different father. These fraternal twins are genetically half-siblings and share 25% of their DNA.

Monoamniotic/Monochorionic: identical twins that are not separated by any membranes in the womb. These can be subdivided into 4 types.
-Dichorionic Diamniotic: before the yolk sac is formed, each twin has his/her own placenta
-Dichorionic Diamniotic-fused placenta: after the yolk sac is formed twins share the placenta, but have own chorionic and amnionic sac
-Monochorionic Diamniotic: a day or two later after yolk sac formation twins share placenta and chorionic sac, but have their own amnionic sac
-Monochorionic Monoamniotic: several days after yolk sac formation twins share all three (placenta, chorionic sac, and amniotic sac)

Twinning rates:
2.6% of births in 1997 were twins
One in 50,000 births results in conjoined twins.
Fraternal twinning by racial background:
-African 1 in 70 births
-Caucasian 1 in 88 births
-Japanese 1 in 150 births
-Chinese 1 in 300 births

Interestingly enough, my ex's grandfathers were identical twins. They married sisters. I tried to explain to his mother, but she didn't believe me, that her cousin and she were, therefore, half-sisters.

Had the wives been identical twins, they would have been sisters, as both sets of parents would have shared identical genes, and Helen and her cousin would have shared identical genes from their fathers and identical genes from their mothers.

As it was, they, in essence, shared the same father and were, genetically, half sisters, as well as being cousins. Despite the fact that she had been a nurse and should have been able to understand this, she thought I was wrong.

"This theory arose when it was determined that conjoined twins invariably "

I should have finished this:

This theory arose when it was determined that conjoined twins are often "mirror" twins.

Gee, we've really completed the topic drift, dontcha think? Or should we discuss astronomy?

"hair", if you will peruse the backlog, is not a drift from the topic of this thread. Indeed, hair and curtains seem to be of paramount interest.

hair does seem to have a strange pull here, doesn't it?!

I don't think enough people have talked about *my* hair yet.

No one wants to be compared to your loveliness, my dear.

Anyway, you're young, you have years of compliments ahead of you. Some of us need to make up for lost time. *Runs hand through salt and pepper, thin, and scraggly beard.*

Last night, my niece was very helpfully pointing out that my brother-in-law has a little bald patch which is appearing for no apparent reason above his ear. When I said that he was probalby really thrilled that I pointed it out to me, she said, "He doesn't mind, he has a really big one on the top..."

My sister said (loudly) "Shhhhh... he hasn't noticed it yet!"

This was the same niece who whe she was about 4, said "Daddy's head is growing faster than his hair!"

Excellent!

Some men waste their hormones growing hair atop their heads. While others use their hormones to . . . grow salt and pepper, thin, and scraggly beards.

I resemble that remark! Well not really. But my oldest confronted me a few years ago with the statement that she wanted to *do* my hair. Turns out she was just trying to cover the thinning part at the back. It hasn't thinned any more (thanks to good, clean living and a strong set of morals....oh, never mind) but she declared after a couple of minutes. *Your screwed, Dad, it just won't comb over!* Ahh, the joys of fatherhood. I suppose my response to that statement is why she moved to Asia......

btw, my youngest is coming back from Thailand tomorrow and my oldest from Taipei next week!!! Time to start cooking!

cl's isn't exactly *thin and scraggly* though, is it?

Neither is jwf's, and they are both old old men.

... and while we're on the subject, what about MY hair? (I'm always happy to join in with bizarre fixations like this.) I don't think my 'can't be bothered to shave very often' stubble can compete with jwf's beard though.

You know why young uns say things like that, don't you? They can run faster...

and some women find salt and pepper, thin, and scraggly beards highly irresistible.... (on men, that is...)

You know the joke...

God one day realized how hard women work in life and was trying to think of a reward for them.

"Women reach a certain age where their hormones are acting up, they feel unloved, and after lifetimes of looking after their men and their families. They need something to perk them up... What should I give them to show them how much they are honored... I know, I'll give them a beard!"

*looks at Dogster's picture, looks at posting, looks at picture again, then the posting*

Hmmmm.

Oscar had it right, youth *is* wasted on the young...

And given that my entire identity here on hootoo is dependent on my haircolor, you think at least ONE of you would have commented...