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QI - How would you spot a Neanderthal on a bus?

GeeSussFreeK says...

>> ^castles:

I've heard things like 'we share 93% of our DNA with slugs' or something like that - so what does it mean that only '1-4% of our DNA is Neanderthal'? Can someone explain?
EDIT:
Here's the kind of stuff I'm talking about..
Mice, men share 99% of genes
Humans related to humble mud worm
Genome Study Finds Rats, Humans Share Stretches of DNA


The difference is hereditary and pair structure. Genetically speaking, many of the chromosome base pairs are nearly identical from animal to animal. Reproductively speaking, there can't be to much variance in the chromosomes for successful mating. A rat can't mate with a human for example. However, other pre-Homo sapiens's and Neanderthal could, and unlike mules, mate and have non-sterile offspring. The 1-4% is direct ancestry. If you were to compare, like that study did with mice, actual base pair similarity, it would rank higher than chimps most likely (99.9999% or something). However, there is a chance that they are more dissimilar than chimps, and through some reproductive fluke, were still able to have virile offspring. The point is, the difference he was highlighting is the direct mating heritage of early man with Neanderthal, much like someone saying they are 4% Indian, even though they are both 100% human.

Lloyd Pye Loves His Alien Skeleton

nach0s says...

This is interesting, but it raises red flags that the skull is named 'star child' before any real conclusions are made. Where is the alternate explanation of what this is? It certainly seems that the desired outcome is what is driving the interest in this skull. He also keeps referring to science as 'they', without citing any actual studies or inquiries.

I'm not a scientist, but the theory of evolution states that occasional random mutations appear in the genetic lineage of a given species, and when that particular trait is passed on, the development of that species changes. Could the genetic differences in this skull be explained as a mutation that didn't get passed on? Isn't that more likely than "a human mother gave birth to an alien baby"?

Here are some excerpts from the wiki entry:

DNA testing in 1999 at BOLD, a forensic DNA lab in Vancouver, British Columbia found standard X and Y chromosomes in two samples taken from the skull, "conclusive evidence that the child was not only human (and male), but both of his parents must have been human as well, for each must have contributed one of the human sex chromosomes". Further DNA testing at Trace Genetics, which specializes in extracting DNA from ancient samples, in 2003 recovered mitochondrial DNA from both skulls. The child belongs to haplogroup C, while the adult female belongs to haplogroup A. Both haplotypes are characteristic Native American haplogroups, but the different haplogroup for each skull indicates that the adult female was not the child's mother. Trace Genetics was not able to recover useful lengths of nuclear DNA or Y-chromosomal DNA for further testing.

Explanations
Potential explanations for the skull's unusual features include the use of cradle boarding on a hydrocephalic child, brachycephaly, Crouzon syndrome, congenital hydrocephalus, or potentially progeria.

Zero Punctuation: Shadow of the Colossus

I'm 80% Girl, 20% Boy

HadouKen24 says...

>> ^DuoJet:
I don't get it. What mistake was made? Even before I learned that the giant boobs were fake (at the 5:30 mark), I suspected this was a gay male. This person looks, behaves and speaks like a gay male.


Her boobs were fake? I doubt it. At the very least, not they're entirely fake. Hormone treatments--or for someone with Klinefelter's syndrom (XXY sex chromosomes), the cessation of hormone treatments--would cause such growth in breasts. Though this woman could have gotten implants as well, I find that somewhat unlikely. That kind of surgery requires money, which she doesn't seem to have.

EDIT: Also, she probably has something other than Klinefelter's as well, if her genitals were ambiguous enough at birth to require surgery. Klinefelter's alone results in apparently normal male children. Which makes the "cessation of hormone treatments" explanation even more plausible.

Our Lowly Origins / lovely Origins ;)

What does feminism mean? (User Poll by MycroftHomlz)

rebuilder says...

I picked "advancing the rights of women" because the roots of feminism lie in the historical oppression of women in society. Now, certainly the stated goal of feminism has been equal rights for women, but much of the public discussion has centered on the advancement of women's rights as the method for achieving that. I feel this is an important point to consider. With such a goal, how do you know when you've reached it? How do you know when you should stop advancing one group's rights? How do you even define your groups? There is no objective viewpoint to take, subtle oppression is difficult to quantify. The risk of exaggeration is inherent in any attempt to increase the rights of one group of people only.

Now, certainly feminist theory acknowledges, even actively propagates the point that it is not just men who perpetuate restrictive gender roles, and not just women who disavow them. Gender roles, as far as I can tell, are seen in feminist theory as a powerful meme that resides in all our minds, and restricts us all. Men, too, are bound by their roles, although those roles may traditionally grant them more power than the roles of women. I agree with this assessment to a large extent, and that is why I find it disappointing that feminist rhetoric remains so gender-centric.

"Feminism", "patriarchy", "sisterhood", "matriarchy" - these are all terms stuck in an old-fashioned mode of thought. Rhetoric using these terms is likely to be counterproductive now. Like it or not, a lot of people identify with their gender, partly for cultural reason, partly because most of us are hard wired to seek gender roles, whatever they may be in our culture. To say a society is patriarchal may be accurate, but it perpetuates a division that should not exist. A man is likely to take such a claim as an attack on them personally, because it implies that the male sex oppresses the female sex, making anyone identifying with the male sex an oppressor.

There is a paradox here I'm having difficulty putting into words. That gender is not really an either-or thing, but rather a diffuse gradient, or a combination of many gradients, seems to be a fairly widely accepted claim in feminist theory. Humans have a wide variety of attributes, too many to reasonably list, that vary with cultural background and hormonal makeup. Some people are more aggressive, some people better able to empathize with others, both traits likely influenced by nature as well as nurture. Gender affects us; to say that the mind of someone with XX chromosomes is not, on average, influenced by a different set of chemicals than that of someone with XY is foolishness. (For simplicity's sake, let's not get into women with Y chromosomes, men with double-X etc. here.) It is equally foolish to claim that simply based on someone's perceived gender you could tell what their abilities are. Gender matters, but individual variation matters more, so it seems silly to group people into "women" and "men" for purposes of defining what their rights are or should be. Still, this is effectively the division a lot of feminist rhetoric perpetuates by continuing to use gender-specific terms.

If you accept that individual variance trumps gender-based differences, I do not see how you can talk of women's or men's rights. The terms lose meaning. To say anything about women's rights implies that there is, for social purposes, a well-defined group called "women". If your goal is to let people live their lives however they please regardless of their gender, such segregation is counterproductive. There are human rights, and that's all.

In summary, fuck isms. Fuck them hard.

Anal Pillow Talk

shole says...

>> ^MarineGunrock:
Let's not forget that the prostate gland has been referred to as the "male's clitoris."


i'm fairly sure you mean 'male g-spot'? (though even that is a bad comparison)
the tip of your dick IS literally the 'male clitoris'
it's the same piece of flesh that only bends to shape by what your chromosomes read

Noir Desir - Le Vent Nous Portera

paul4dirt says...

I'm not scared of the road
We should see, must taste
From meander in the hollow of your breast
And there everything will be ok
The wind will carry us

Your message to Ursa Major
And the trajectory of your race
An instant of velvet
Even if it's not useful though
The wind will take it away
Everything will disappear but
The wind will carry us

The caress and the grapeshot
And that wound that tears us appart
The palace of everyday
From yesterday and tomorow
The wind will carry them

The genetic in shoulder-belt
Chromosom in the atmosphere
Taxis for galaxies
And my flying carpet says ?
The wind will take it away
Everything will disappear but
The wind will carry us


This perfume of our dead years
What can knock at your door
Infinity of destinies
We lay some but what do we retain?
The wind will take it away

During the tide rises
And everyone is doing its accounts
I take in the hollow of your shadow
Dusts of you
The wind will carry them
Everything will disappear but
The wind will carry us

(yt)

Antigenic Shift - The Spread of a New Mutated Virus

Doc_M says...

^That's getting there, but is not entirely the case for flu viruses.
The case you referred to in the pic was a "bacteriophage" which is what most people picture when they think of a virus. that one only infects bacteria and its genome becomes part of the infected host's. It also exits an infected bacteria by destroying it and flooding out.

Flu on the other hand, does not become a part of your DNA genome and doesn't kill the cell to get out. Here's a nice flash presentation that shows what happens:
http://www.nescent.org/eog/influenza_life_cycle.swf

You can notice the many bits of DNA that get into the cell from the virus. Influenza has a multi-unit genome... you can think of it like our chromosomes sort of. When TWO different strains of flu infect one particular cell, the virus that is produced in the end can have some of the bits of DNA from one and some from the other... in essence, producing a new strain which is a sort of daughter of the original two parents. So in a way, I guess you could call it "sex" metaphorically. It's one of the best ways for producing genetic diversity in flu and it's why you have to get a different flu vaccine every year. They try to make their best estimate what will be the common strain for that year. What a pain.

TED 2008: On the verge of creating synthetic life

siftbot says...

Tags for this video have been changed from 'genetic programming, artificial virus, printing chromisomes, designer species, oil' to 'genetic programming, artificial virus, printing chromosomes, designer species, oil' - edited by kulpims

Psychologic (Member Profile)

grinter says...

Just to let you know, I posted a reply in an attempt to answer your question about evolution through chromosomal aberration. I'm not a cytogeneticist, but I've tried to explain my understanding of things.

In reply to this comment by Psychologic:
One idea he doesn't cover is how the evolution of one species eventually gives rise to other species with a different number of chromosomes. I think this area of evolution is what led to the "dogs giving birth to cats" argument. A member of a species that gains or loses a chromosome through mutation shouldn't be able to reproduce with the relatives or its parents.

The explanation I have seen for this event is that it requires multiple individuals within a population to have the same non-detrimental mutation, in which case they could mate with each other to perpetuate their own new line of organisms. Obviously this would be an enormously improbable event, but when you're talking about billions of chances over countless years then it would almost certainly have to happen at some point.

Is there any other explanation for this situation that I am not aware of?

Evolution

grinter says...

Psychologic, you are correct in saying that individuals with split, merged, extra, or in other ways funky chromosomes (aneuploid) are usually not viable, and are often sterile. However, if the individual is viable and fertile, finding a mate with the same issue is not always necessary. A beneficial aneuploidy can be passed on much as any other beneficial trait. And, with a terrific amount of luck, can increase in frequency within a population.

For instance, in humans with Down's syndrome, although fertility is severely reduced, many females can have children. You can imagine, that if this trisomy were in some way adaptive, it could eventually sweep the population. The rest of the genome would then likely evolve to accommodate the trisomy/new chromosome, and fertility would increase.

Here is a really neat paper where yeast evolve via aneuploidy to overcome the problems that occur when researchers delete an important gene:
http://www.cell.com/abstract/S0092-8674(08)01196-3

As for needing to find a mate with a similar chromosomal aberration, you may be thinking of evolution through polyploidy, when the the entire chromosomal compliment is doubled (like you see evidence of in many plants and salamanders). That really screws things up, but because of the way in which plants reproduce, 'gametes' with double sets of chromosomes are common. Combine that with self fertilization and you have reproductive isolation and a new species in one generation.

Evolution

Psychologic says...

One idea he doesn't cover is how the evolution of one species eventually gives rise to other species with a different number of chromosomes. I think this area of evolution is what led to the "dogs giving birth to cats" argument. A member of a species that gains or loses a chromosome through mutation shouldn't be able to reproduce with the relatives or its parents.

The explanation I have seen for this event is that it requires multiple individuals within a population to have the same non-detrimental mutation, in which case they could mate with each other to perpetuate their own new line of organisms. Obviously this would be an enormously improbable event, but when you're talking about billions of chances over countless years then it would almost certainly have to happen at some point.

Is there any other explanation for this situation that I am not aware of?

Gaza Villages Wiped Off the Map

Pprt says...

I assure you I understand the point of view that the Muslim Palestinians are the underdogs and that they supposedly are a modern "ressistance" movement.

But I think the crux of the question is whether Muslim (or Christian) Arabs can live peacefully among Jewish people or if Jewish people can live peacefully among Muslims. I use religious terms here because, unfortunately, some people are still convinced that "prophecy" is relevant when in fact we've got people working with chromosomes and gene sequencing as we speak.

My opinion, looking at the current state of affairs, is that Palestinians would be far better of living in Israel than Israelis living in Palestine. Unfortunately the likelihood of this happening is beyond probability.

>> ^Farhad2000:
Look the onus is on you to justify the numerous deaths and destruction the IDF has unilaterally applied to all Palestinians.


My argument, to answer your question, is that Israel is a very responsible state in that it adheres to what is generally acknowledged as the peak of "civilization" in the form of political, economic, personal, social, educational and spiritual liberty. Did you know that there are even "anti-discrimination" laws in the Israeli penal code?

As for armed combat... war is horrible, but the soldier who has the courage to wear a uniform has more honour than the man hiding behind women and children. There's no argument against that.

Who thinks Powell's Endorsement was Based on Race? (Politics Talk Post)

Octopussy says...

QI, actually. A lot of feminists were upset about Hillary not making it and some are still confused about whether or not to support Palin. Which, frankly, I think is absurd, but apparently it is ok to think along those lines. So it almost seems as if women supporting a woman just because you share XX-chromosomes is fine, white people voting for other white people has been the standard for decades, but someone with Jamaican parents endorsing a person whose father was from Kenya is suspicious.

Fortunately, Powell did a great job in explaining why he made his choice. And I personally believe his endorsement is probably more anti-Republican than anti-white.



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