[bugmenot]

It seems that in humans the females genes seem to be the ones passed on to offspring more than the males while in other mammals the males genes are the dominant ones like horses, dogs. Is that true?

Would human breeding be possible in order to get the best possible offspring even though the human species is more complex than any other species?

If a male carries a certain trait and the females does or does not carry the same trait will the males trait pass on to the offspring? It seems to me that the females genes make the final decision on that.
How would someone know if a trait will get passed on or not?

It also appears to me that human females evolve faster than males as far as I could tell from physical attributes. Is that true?

[Fishteacher73]

bugmenot said:

It seems that in humans the females genes seem to be the ones passed on to offspring more than the males while in other mammals the males genes are the dominant ones like horses, dogs. Is that true?

Would human breeding be possible in order to get the best possible offspring even though the human species is more complex than any other species?

If a male carries a certain trait and the females does or does not carry the same trait will the males trait pass on to the offspring? It seems to me that the females genes make the final decision on that.
How would someone know if a trait will get passed on or not?

It also appears to me that human females evolve faster than males as far as I could tell from physical attributes. Is that true?

First off I would recomend some studying of basic genetics. You first statement is simply unfounded. You have dominant and recessive alleles. Traits (phenotypes) are expressed through a variety of ways.
1. Complete dominance- the dominant gene (usually represented by a uppercase letter) is the trait expressed.
2. Incomplete dominance- The hybrid (Aa) shows a blend of both traits. EX. red cross w/ white...some are pink.
3.Codominance- Both traits are expressed. (AB blood tyoe).
4. Mutiple allel control- a number of alleles control a single trait. EX eye color is controled by six sets of allels.
5 Sex linked trait- A trait that is cariied on either the X or Y chomosome. If it is carried on the Y chomosome only males will exhibit this trait. Traits on the X chomosome are suppled by the mother in all males. So what ever traits are carried on the x chomosome in the male are expressed.

Sex determination can vary greatly. Some can be temp. dependent (somr corcs and reptiles) others are controlled by the ploidy (number of sts of chomosomes..in many insects if I recall) and some are controlled by the female.

I think it would be streaching it greatly to consider humans the most complex organisms.

Individuals do not evolve species as a whole do, so one sex cannot evolve faster than another.

[bugmenot]

Fishteacher73 said:

5 Sex linked trait- A trait that is cariied on either the X or Y chomosome. If it is carried on the Y chomosome only males will exhibit this trait. Traits on the X chomosome are suppled by the mother in all males. So what ever traits are carried on the x chomosome in the male are expressed.

I don't understand that. Could you please tell me of an example of a trait and how it would end up in the offspring?

[sciborg]

Female humans do have slightly more DNA than males (a few percent).

Also the DNA in mitochondria comes only from females.

Finally, the original copy of the machinery that reads the message in DNA comes from the female.

See http://www.azinet.co...g/Genetics.html

[Tormod]

sciborg said:

Female humans do have slightly more DNA than males (a few percent).

I am trying to find evidence for this...can you point me to it?

And for a humorous take on the 78 different genes between men and women:
http://news.bbc.co.u...ews/3002946.stm

[niviene]

Well, since the X chromosome is the one required to survive... But, a few anthropology courses many years ago don't make me an expert on the subject. Only the strings of what I remember..

Here is an interesting article - who knows how accurate this is, but it's an interesting thought on the "sunset clause" on the Y chomosome.

http://www.abc.net.a...ries/s73264.htm

[Fishteacher73]

Tormod said:

I am trying to find evidence for this...can you point me to it?

The human x chomosome has aobout 155 million base pairs. The y chomosme only about 50 million pairs.

Since females have two x chomsomes and males only one, females will have about 100 million more base pairs. The distinction must also be raised that in female cells onl;y one X chomosome is active, the other beocmes dormant and is refered to as a Barr body. The specific chomosome that is active will vary from cell to cell. That is to say that different x chomosomes are active in different cells. A good example of this is tortoise shell coloration in cats. Coloration is carried on the x chomosome in cats. The motled appearance of tortoise shell cats is caused by different x chomosomes being active in different cells producing the coloration. Males cannot be tortoise shell (although it might occur if there is a feline variation of Klienfelter's Disease. A genetic anomoly that produces XXY males in humans).
So in actuality, while females have more geteic material in their cells, males actually have more active genetic matierial because both the X and Y genes are active. So in realitty males have more funtional DNA in their cells (about 50 million more base pairs).

http://ghr.nlm.nih.gov/chromosome=Y
http://ghr.nlm.nih.gov/chromosome=X

[lazo.alex]

Hmm.. well, im new to these forums (hey there). also, i dont have evidence for this, but i once saw that there is a certain species of lizard that does not have males. The females can reproduce themselves, they have the ova, and they fertilize it themselves. (though they still make some mating ritual before reproducing, which indicates males existed.)

So the hypothesis is the following: many years ago, the Y chromosome was a lot bigger, and it has been observed that it is still getting smaller. What if this Y chromosome was to dissapear? maybe males in the future will be an extinct race, and females would be able to reproduce alone.

Sorry for my english, im not native speaker, greetings from Peru to all, these forums are great

[MortenS]

Whiptail lizards (genus Cnemidophorus) reproduce in the way you describe, lazo.alex

While the reproduction is asexual, they still require sexual stimulation for high fecundity.
One female assumes the male role, and mounts the other female that is about to lay eggs.

If kept in isolation, the asexual females have a lesser fecundity than those that get to act out courtship, presumably because of lesser hormone levels when isolated.

The origin of these asexual lines of reptiles are due to hybridization between two species.

[bugmenot]

niviene said:

Well, since the X chromosome is the one required to survive... But, a few anthropology courses many years ago don't make me an expert on the subject. Only the strings of what I remember..

Here is an interesting article - who knows how accurate this is, but it's an interesting thought on the "sunset clause" on the Y chomosome.

http://www.abc.net.a...ries/s73264.htm

Quote

Chromosomal conditions involving the sex chromosomes often affect sex determination (whether a person has the sexual characteristics of a male or a female), sexual development, and the ability to have children (fertility).

I always believed in that. There is strong evidence of that today in many species.

I read that article and I always believe that males would disappear of the face of the planet and would be the first to become infertile, like the article said. That's very sad. I always thought that it would be a good idea to preserve genes from the oldest humans found like cave men in order to some how fix problems when they arise in the future because of the genes inability to stay potent against time. That article really made me sad and told me what I always knew. Even though I will not be around to see that happen it still is quite sad.

The females have 2 x chromosomes and the male has a x and y. So there is a total of 3 X chromosomes if they are combined and the female has the most X chromosomes which is why their genes count more and in the end and the same reason why males will become obsolete. I still have my question.
In the end it is the female who provides the most genes to an offspring. Correct?

This is all very interesting. I always saw women/female species as being far more developed than men/male species and much more refined in every way. Superior in many ways.


Can someone tell me what the future of reproduction is? Will females evolve in order to reproduce asexually.

The article said the causes of the Y chromosone disappearing are evironmental factors, chemicals and other things.

Quote

The cause in the real sense of it will be many of the environmental factors, that's for certain. Because we know that we can induce mutations dramatically in animals by exposing them to specific compounds. Now lower or not so severe mutation rates will occur under exposure to all sorts of other chemicals. So as we raise some of these chemical levels, and pesticides have been a concern. Organopesticides have been a real concern for us, and I think the mutations will move up, they will quicken up. This is the opposite of course to genetically modified organisms, we probably need them in more quickly than the society really thinks, to protect us.

I strongly agree with this hole article not just this part. If the source of the problem is known and this is happening NOW why isn't anyone doing something about it in order to allow the Y chromosone to fix itself and restore balance between repair and damage.

[SunsetClause]

This is bugmenot again. Had to register a new username since bugmenot was not my account.

Does anyone know where to get tested for y chromosome deletions? How much would something like that cost? Would be interesting to know what parts I'm missing.

Putting in "sunset clause on the y chromosome" in google gives only 477 results.
This should be the news of the century. 99.99% of the world population has no idea this is actually happening now.

Is there anyway to prevent this from happening?
Is there any other information on this?
Is there any Geneticists looking at this and following this currently?
Is this that inevitable that there is nothing that can be done to prevent it explaining why there is no info available?
Does anyone even care?

[SunsetClause]

Nobody cares. I guess sometimes when you have to go, you have to go.

[learnin to learn]

It has been awhile since I have studied the X and y chromosomes, but isnt a persons sex decided by whether or not the male's sperm gives an X chromosome?I loved the site Tormod!!!!

[SunsetClause]

There's sperm that are y or x. x is female and y is male. Read the sunset clause. I swear if men and women knew about the sunset clause women would say "yes" more often

[learnin to learn]

lol I bet they would