“Prometheus has landed!”

In a future world, on the Isle of Skye, Elizabeth Shaw (Noomi Rapace) and her lover Charlie Holloway (Logan Marshall-Green); have uncovered the final piece of evidence that proves millions of years ago, Earth was visited by another race, this race left an invitation inviting the human race to come and visit. Two years later on the space craft Prometheus Shaw, and Holloway are joined by fifteen others who awake from hyper sleep at their destination, a distant planet known only as LV277. Among their fellow passengers is Meredith Vickers (Charlize Theron) a hard nosed business woman, who unofficially controls the expedition, and David (Michael Fassbender) an ultra efficient, ultra expensive human looking android, the creation of Peter Weyland (Guy Pearce). Their combined mission, to seek out the mysteries of our origins, and to finally prove we are not alone, what they find was well beyond their expectations.

“If we don’t stop it, we won’t have a home to go back too!”

Prometheus is a magnificently crafted thing of beauty, it shines, it has the ultimate glint of panache, it moves, it literally lives! But what it does not do, is answer all the questions; a thing of annoyance to many. Prometheus is not the finely tuned beast that Alien was, but here is the point, it is not the same thing that Alien was. If you go into Prometheus in search of Face-Huggers, and Chest-Busters, you’re going to be sorely disappointed, despite what you think you might have seen in the many trailers.

Performance wise, all the cast do exceptionally well, despite the obvious and clear lack of development of many of the characters. This is not the close knit group that we saw in Alien, in fact we have double the amount of characters to contend with, so obviously some get less developed. Michael Fassbender, everyone’s must have actor of the moment, ultimately steals the show as the android with an agenda, but a creature who wants so very much to be like us.

Like any good movie of this type, a body count is pivotal to the movie, and like Ridley’s aforementioned Alien, the order in which they fall is a little unexpected.

Two days after Prometheus’ first reviews hit the public eye, and the balance is mixed; many feeling disappointed by the betrayal. But Ridley has been very clear from the offset, this is not Alien, despite the many similarities, this clearly is a very different beast indeed, and truth be told despite what you think you may be seeing in trailers, the only real link comes in the final seconds, and those that think Prometheus ends where Alien starts, may want to revisit Alien to see just how wrong they are. The planet in which Prometheus is set, is not the same planet we see in Alien, so maybe another chapter will give that some clearance.

The 3D effect is a let down, after a promising start, as the movie proceeds you forget all about the 3D, as the action really kicks off 3D is all just a distant memory.

“A King has his reign, then he dies. It’s inevitable!’

Prometheus is an incredibly good movie, it’s a brand new twist on an old tale, but more than anything else its an evolution piece, the evolution of us, the evolution of the engineers, the evolution of LV277’s newish inhabitants, and finally the evolution of the “alien”, it’s roots so to speak.

As you exit Prometheus you really do understand that this movie was made to become a franchise, the reason so many questions are left unanswered is so that in years to come, a new chapter can open up some of the mysteries, Prometheus may not be as appreciated as it should be right now, but in years to come as the franchise builds maybe like its predecessor it will become known as a masterpiece.

Not that it was really needed, but as a testament to the love of the movie (before it was seen) outside off Leicester Square’s blue carpet, the largest fan audience of all time gathered for a glimpse of the stars that populate the film, watch out Harry Potter, there is a new audience puller in town.

 DNA is a molecule with a structure like a spiral staircase. Each conductor is constituted by units of pairs of chemical substances that bind to one another, the replication of DNA in the form of coffee itself each DNA strand with a base sequence specific. Each base is also of a molecule of DNA molecules of sugar and fosfat.Molekul connected in the body, arranged in packages called chromosomes. Every human being has 23 pairs of chromosomes. One of the 23 pairs of chromosomes, called sex chromosomes that differ in men and women. Females have two X chromosomes, males have X and Y chromosomes Every organism has a number of different chromosomes.

DNA testing is the analysis of models of DNA (genetic profile) of a person. For the purposes of DNA analysis a sample of cells from body tissue (usually skin) was added. DNA is then purified from these cells and the pattern of variation of DNA sequencing machines, such as a bar code read by reading. DNA results for reading bar codes are then analyzed DNA from a person’s body at 100% the same no matter where you take the test. Each model has a unique DNA like a fingerprint. Since the middle of the model of DNA is inherited from the mother and half is inherited from the father, is half the lines of the bar code as a son of the DNA can be aligned in the DNA of the father, the other half, as the report mother-DNA. If there is no parent-child relationship, it is 50% to be similarities. DNA between siblings also have some similarities, but unlike the parent-child relationship DNA tests as a post-mortem on the victims of air crashes, test results are used by the owner of the bodies of victims and piece together to identify the individual parts his body.

True IMEI number can not be changed. Because it is inherited from the manufacturer / vendor who makes it.

You can also block your IMEI number if your phone is lost stolen or used by people who are not responsible. So, keep your cell phone IMEI number and record it. Because who knows in the future, if at any time you lose your phone, you can block your phone from being used by others.

photo: Keep the victim Shukoi Evacuated (detikNews)

This way will take much longer for the families of the victims. Butthis is to avoid mistakes or any body part that is less time of submission later.

“It will be done simultaneously after DNA tests on all the victims. We ask families to be patient,” said Police Chief RS Soekanto DR, Brigadier General Agus Prayitno, Monday (14/05/2012).

Earlier this afternoon he declaredto have received 22 bags of evacuation teams. A total of 18 bags containing body parts of victims and the remaining four contain personal items belonging to victims will also be identified.

“We also sort out the pieces of the victim based on race. That is Caucasian and Mongoloid, but theamount can not be ascertained,” said Agus.

On the same occasion passenger Commissioner Head Boy Rafli Amaradded, the process of identifying the bodies will be based on suitability tests on the teeth, fingerprints, forensic anthropology, technical, and DNA. The most recent inspection is DNA, because DNA testing is the most important for identification.

“DNA testing is the most muktahirtechnology and the highest accuracy,” said Boy.

1. As well as fingerprints, we have toe prints, palm prints, and foot prints. All of these are unique.

2. Any two of your fingers have different fingerprints. So fingerprints don’t just say which person made them, they say which finger (or toe, etc.) on which person made them!

3. Even identical twins, who have identical DNA, have different fingerprints. This is because fingerprints aren’t caused purely by genetics, but also by minor environmental influences in the womb.

4. Other animals with unique fingerprints are chimpanzees, gorillas, and koalas. A fingerprint from any of these animals is so similar to human fingerprints that even experts can be fooled.

5. As well as unique fingerprints, you have unique irises (the lines in the coloured parts of your eyes) and a unique pattern of hair follicles on your head.

6. Fingerprints are thought to help us grip things when our hands get wet. Our skin absorbs water and swells up, but fingerprints keep the tips of our fingers rough so we can still hang onto things and not slip off.

7. Zebra stripes, tiger stripes, and many animal irises are as unique as fingerprints.

8. Fresh pineapple juice contains a naturally-occurring chemical which wears away fingerprints. If you leave your hands in pineapple juice overnight, you will wake up without fingerprints. There are also ways to surgically remove fingerprints. Of course, since so few people do this, it actually makes you easier to identify by police (yes, it has happened).

9. If you scratch your fingertip badly, the scar will remain in your fingerprint forever. Unless, that is, you scar yourself as a baby before you are 6 months old. This is because most minor injuries up until this point in life leave no scars due to the healing abilities of newborns which we lose as we grow older.

10. There are different categories of fingerprints. Have a look at your fingers to find out which ones you have. There are: arches, whorls, loops, and double-loops. The loop is the most common, but on a few of your fingers you might have something else instead.

1. Every aspect of our physiology, every hair colour, eye colour, height, nose shape, predisposition to diseases, asthma, colour blindness, and so on, is due to DNA. Every living thing, including you, has DNA in every part of them. And the DNA is always unique to them. No two people have the same DNA, except identical twins.
2. DNA is divided up into pieces called ‘genes’. A gene is a piece of DNA that determines some attribute, like how long your toes are.
3. We have two copies of every gene. This is in case one copy is a bit dodgy, or has been damages, and we can use the good copy as backup. A person might have one gene for blindness, but another gene for normal vision, so they can still see fine. But if both their copies for that gene are for blindness, then they will be blind. But this is rare. Most of the time, the backup is healthy.
4. If you are related to someone, most of your DNA is the same.

Now, why is it bad if you marry your sister or brother? Apart from the obvious squeamishness, it is bad genetically. There is a lot of truth in the legend that your children together will be deformed and mentally retarded.

When two people, or animals, reproduce, the offspring takes half its DNA from the mother and half from the father. Half the DNA is from the egg and the other half is from the sperm. This is why children tend to look like both their parents.

You have thousands of genes. Unfortunately, you have about one hundred genes that are faulty. Sorry. They would normally give you all sorts of nasty diseases and conditions, but fortunately you have two copies of every piece of DNA. So even if you have one bad copy, chances are you have a healthy copy also that overrides it. This is true for just about all creatures on Earth. We all have some dodgy DNA, but because we have an extra copy, we overcome it.

Now, if you are related to someone, you share a lot more DNA than usual. You and your sibling have much more in common than you and a stranger from the other side of the world. This means that your sibling probably has most of the same bad pieces of DNA as you. You both have the same dodgy genes which are overcome by the healthy ones.

If you have a child with your sibling, the child also gets two copies of every gene. He or she takes one copy from you and one copy from their other parent. Now, there is a 50/50 chance that they take your dodgy one for any particular gene. That’s normally fine. However, if the parent also has a copy of the dodgy gene, then the child also has a 50/50 chance of taking their dodgy gene. The result? A much higher chance than normal of the child ending up with two copies of the dodgy gene and no healthy gene to override it. They get bad DNA and no good DNA. And bad DNA can cause all sorts of problems, depending on which part of the DNA it is. They might be deformed, sick, mentally disabled, or stillborn.

If you have a child with someone unrelated, the child still has a 50/50 chance of inheriting your dodgy gene, but an unrelated person is extraordinarily unlikely to have the same dodgy genes as you. They’ll have their own hundred or so bad bits of DNA, different to yours. So even if the child does get your bad gene, since the other parent only has two copies of the healthy version of the gene, they will just about always end up with a good gene as well, which will override the bad one.

In short: don’t have children with people you are related to. They are highly likely to end up with two copies of some bad DNA. Plus it’s pretty gross.

How is this relevant? Well, imagine we have some dinosaur DNA from a drop of blood in amber or something. Now imagine we have perfected cloning so that we can grow a dinosaur from it (we are far from being able to do this. Even dolly the sheep had many health problems and a very short life expectancy). If we get two dinosaurs and have them reproduce, we are basically talking about incest. Dinosaur incest isn’t as squeamish as human incest, but the genetic results are the same: the baby dinosaur will end up with a few dozen genes where it only has bad DNA, and no back-up copies of good DNA. It will have bad genes. It will be deformed, sick, and might not live more than a day or two. Our revived dinosaurs won’t be able to reproduce, since all the babies die or are too unhealthy to reproduce themselves. We can’t just clone a few dinosaurs and expect them to repopulate their species.

Unless we have the DNA from several dinosaurs, all of the same species of course, then we can’t clone them and bring them back. We need variation in the DNA, or all the babies will be sick and die before they can do much. And even if we did have lots of samples of dinosaur DNA, our cloning technology is shaky at best, and not equipped to handle such a thing without a living dinosaur to act as an incubator in the first place.

So sorry. We can’t bring frozen mammoths back to life. We can’t revive the thylacine. And, as much as I hate to say it, Jurassic park is still a long way away.

Subject: Close relative

For years a loved one behaved just like everyone else: grew up with a few challenges, excelled at sports, music and arts.  Besides being brilliant at many things, this person was funny, fun to be with, easy to entreat for years. Even became a professional, excelling in the chosen field with a University double degree. So, what happened to make this person lose it completely without doing drugs, even coffee or cigarettes?

I could not classify myself as a psychologist, but I have an acute memory, a diligence to search out the truth of a matter and the determination to help a living soul in limbo. When this subject became phobic to a mental degree literally throwing away his past life and everything inside it, down to his last dollar, we began to be alarmed.  Alarmed to the point of distress and anxiety about the well-being of our loved one. 

Looking back, it appeared that anxieties appeared in the person’s mental decorum when there was a change in relationship, i.e. a breakup of close relationships. This has happened about 4 or 5 times in the past 8 or so years, each time, the anxiety has caused erratic behaviour to appear. In the first instance, a change in location, a move to another state and a change in career direction. Sound familiar? We all have these changes from time to time, for one reason or another, so we didn’t worry too much.

In the second instance, a change in location and accommodation [from alone to sharing], and a return to previous career. No problems here. We would all like to chop and change at times, just to get some fresh air into our lungs.

Changes in relationships happened again, but this time, the change was also seen in the area of talents, from one instrument to another, totally new musical instrument.  We didn’t worry. Again, we all love to try new things in art, music, song, etc. 

Next change: New relationship faded. Location to another state. Budding career abandoned. That is a worrying sign. But, again, maybe we all need a break from our line of work for a time.  The break lasted for a year and a half. In the meantime, the music faded and the talent emerged in another area, singing.  This was new. Why now? Still, we thought everything would simply pan out in the end. The money hadn’t run out.

A few months later: A complete anxiety ridden psychotic event, with all the trimmings, in another state.  It was a concern. But, everything again seemed bounded by some rational thought, a new door opening for a new career in specialized ministry. Maybe everything would go smoothly now? Not so. Things escalated  within a few months. The subject disappeared from present residence without a word. Even the cell phone was disconnected. This was a concern. Police were involved, family shared thoughts, ideas. For 3 weeks there was no contact, then the subject was found, homeless but with a focused lifestyle that was foreign to anything we could imagine. Focused on a targeted ministry that was described as an open door. 

Through myriads of prayers the loved one stayed alive, the first priority of family members. Now, on hindsight, the reasons for this deterioration in rationale? This madness of mind has come about because of the quest to find a soul mate. How can we prove this?

Well, every time a relationship failed, there was a clue left behind. Something that connected that relationship to the loved one by a hidden cord, such as the chosen career. The method used to find the soul mate. It failed, so the career was changed. With the new change to a musical career, it fitted in with the previous relationship, which was strongly affected by music.

In the following relationship (a fantasy relationship), singing was its key. This clue of singing was taken into the following relationship.

In the following relationship, music was deemed unacceptable as a career, but poverty and a sacrificial giving of life to the needy was paramount to other party, so the music disappeared in the next phase of the process. Therefore in the following episode the music was dumped the the important aspect of the previous failed relationship was adopted: poverty! So, the loved one became hopelessly poverty stricken, homeless and penniless.

Still without a soul mate, the loved one continues to exist in a slowed down lifestyle, depending on other aspects of society for their very living.  What will the next episode reveal? 

From my observance, there have been too many changes in close relationships, and these have been the catalyst for serious DNA disruption to the psychological expectations of the subject, or the hidden desire to find that special soul mate.

Think about the Biblical evidence: in the beginning, Adam was created and his soul-mate, Eve was made from a bone of his rib cage. Bone of his bone, flesh of his flesh, intertwined for life, a guarantee that there will be offspring to fill the earth. 

My point of view on this is as follows:

Our most important objective, hidden in our DNA, is a psychological need to find a close companion, the one who seems to make up for our lack.

It is the most primal and important reason for living.

God is the most important link for our spiritual DNA. God must always be placed first in our lives in our hearts, minds and in theory, but God has placed our sublime need for a soul mate in each of us, so that we understand spiritual things through the fleshy things and the communication that is needed for every living human being.

We need to acknowledge our need for intimacy of thought and life with another human being, to enjoy our existence and to excel in every which way possible.

We need to take stock of how we are feeling when relationships bust up and we are set adrift.

We need to talk to someone in depth about our feelings and our shattered dreams. 

If we can’t find a listening ear, talk into a recorder, or go to a beach and talk into the roaring sea (Stay on the shore, don’t risk going in).

We have to talk about things that hurt us. We cannot stay sane if we bottle things up.

I want to help someone with my observations and deductions, which have taken so long to come to any sensible realization. It takes that long, many hours of prayer, meditation, cogitation and talking to someone about the issues is what it takes to get to its root cause. Talking to God also helps the process.

What will happen to our loved one now? We will have to wait and see in another submission. I hope and pray the news will be positive.

As bad as bullying in school and elsewhere is, there’s now proof that children subjected to bullying actually grow older faster.

New research suggests that children who are bullied often age faster on a cellular level than children who have not experienced bullying, or not experienced it frequently.

The researchers from Duke University (U.S.) found that bulled kids are ‘older’ than they are supposed to be and if the cellular aging isn’t reversed (e.g. the bullying stopped), the children would likely be at risk for premature death.

Violence and stress

To prove their theory the researchers examined a portion of DNA called telomeres. These DNA sequences cap the ends of chromosomes, but they get shorter with every cell division, in effect signaling the wear-and-tear on DNA.

Previous studies found that adults who experienced violence as children tend to have shorter telomeres than those with peaceful childhoods. But those studies couldn’t determine whether the telomeres had been shortened because of stress a child may experience or if it was because of adult health problems that resulted from that stress.

To find out which was the case, the researchers used a sample of 236 children born between 1994 and 1995 who had had DNA samples when they were young. After 10 years 17 percent of the children had experienced domestic violence in their households, 24.2 percent had been frequently bullied and 26.7 percent had been physically abused by an adult. (Some kids were already in protective custody as a result of this abuse.) Because some children experienced more than one type of violence, the researchers split them into groups: kids who hadn’t experienced violence (54.2 percent), kids who had experienced one type of violence (29.2 percent), and kids who had experienced two or more types of violence (16.5 percent).

Problem Can Be Reversed

The results of the DNA analysis showed that children in the final group, those who had experienced two or more types of violence, had significantly faster telomere shortening between ages 5 and 10 on average than the other children. The findings held true after adjusting for health, body weight, gender and socioeconomic status.

The violence does not necessarily have to affect the child physically, the researchers said, but the shortening of the telomeres was clearly the result of cumulative stress.

As bad as the premature aging syndrome may be, the researchers point out that there is hope the process can be reversed. A healthy diet, physical activity and even meditation can help.

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A detailed genetic study of the pre-Columbian population inhabiting the Tompullo 2 archaeological site (department Arequipa, Peru) was undertaken to resolve the kin relationships between individuals buried in six different chullpas. Kin relationships were an important factor shaping the social organization in the pre-Columbian Andean communities, centering on the ayllu, a group of relatives that shared a common land and responsibilities. The aim of this study was to evaluate whether this Andean model of a social organization had an influence on mortuary practices, in particular to determine whether chullpas served as family graves. 

Results

The remains of forty-one individuals were analyzed with both uniparental (mtDNA, Y-chromosome) and biparental (autosomal microsatellites) markers. Reproducible HVRI sequences, autosomal and Y chromosomal STR profiles were obtained for 24, 16 and 11 individuals, respectively. Mitochondrial DNA diversity was comparable to that of ancient and contemporary Andean populations. The Tompullo 2 population exhibited the closest relationship with the modern population from the same region. A kinship analysis revealed complex pattern of relations within and between the graves. However mean relatedness coefficients regarding the pairs of individuals buried in the same grave were significantly higher than those regarding pairs buried in different graves. The Y chromosome profiles of 11 males suggest that only members of one male line were buried in the same grave. 

Conclusions

Genetic investigation of the population that inhabited Tompullo 2 site shows continuity between pre-Columbian and modern Native Amerindian populations inhabiting the Arequipa region. This suggests that no major demographic processes have influenced the mitochondrial DNA diversity of these populations during the past five hundred years. The kinship analysis involving uni- and biparental markers suggests that the community that inhabited the Tompullo 2 site was organized into extended family groups that were buried in different graves. This finding is in congruence with known models of social organization of Andean communities. 

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Neandertal admixture vs. Ancient African structure

The case for Neandertal admixture has been made on the basis of the D-statistic. This is a genomewide statistic which quantifies how two modern populations differ from each other at sites where Neandertals carry the derived allele. If population A tends to agree with Neandertals more than population B does, then this is consistent with Neandertal admixture in population A. It is also consistent with admixture in Neandertals from modern humans, and with ancient population structure whereby some humans carry admixture from before the common ancestor of modern humans and Neandertals.

A new paper goes beyond the D-statistic with the goal of trying to decide between two different models: Neandertal admixture in Eurasians or ancient African population structure. It does so by simulating the site frequency spectrum under the two models and comparing the result with the observed shape of the spectrum. From the paper:

Durand et al. (2011) suggested that the ancient structure model results in more variation in gene tree depth than the recent admixture model. Greater variance in tree depth would alter the frequency spectrum but not the D-statistic. Here, we show that the sfs appropriately conditioned can distinguish between recent admixture and ancient structure because it is particularly sensitive to episodes of recent admixture.

This is how Durand et al. (2011) explained this:

However, it is known that ancestral population subdivision result in a higher than expected variance in coalescence times (Wall, Lohmueller & Plagnol 2009). Therefore, ancestral subdivision is likely to result in more variation in gene tree depth when using several samples from the extant population. This in turn will affect the site frequency spectrum of the extant population (Harpending et al. 1998). Designing a statistic to distinguish between the two scenarios will require using more than one sample per population.

Here is how the authors describe their two models, pictured on the left: 

[admixture] In this model, we assume that there was a single episode of admixture at time tGF in the past (t = 0 being the present) from Neanderthals to non-Africans after the migration of humans out of Africa (Figure 1a). With probability f, a non-African lineage was derived from a Neanderthal lineage. The parameter f represents the fraction of the non-African genomes of Neanderthal origin. We define the divergence time of non-African and African populations as tH > tGF. We denote by tN > tH the divergence time of Neanderthals and the population ancestral to modern humans. 

… 

[structure] We assume in this model that the population ancestral to modern humans and Neanderthals was divided into two randomly mating subpopulations (Figure 1b). We assume that subpopulations exchanged migrants symmetrically at rate m per generation. At time T in the past, subpopulations merged into one panmictic population. A similar model was proposed in Slatkin and Pollack (2008). Green et al. (2010) noted that this model could explain the extra similarity of Neanderthals with non-Africans, and Durand et al. (2011) showed that D-statistics could not distinguish between ancient structure and recent admixture for plausible demographic parameter ranges.

I don’t quite understand the ancient population structure model as presented in this paper. It appears that time T (when the populations merged into one panmictic population) precedes the split between modern humans and Neandertals.

This is definitely not what I’ve had in mind when I’ve spoken about African population structure before; rather, I think that within the genus Homo there were at least two subpopulations (let’s call them A and B) that had long-term reproductive isolation. B gave rise to H. sapiens and H. neanderthalensis but some subpopulations of H. sapiensadmixed with A long after the sapiens/Neandertal split. The basis for that model is dual: (i) the late persistence of archaic humans in Africa that no longer exist there and hence may have been absorbed by African sapiens and (ii) the greater genetic variation in extant Africans which is consistent with either an Out-of-Africa bottleneck or an Into-Africa event followed by admixture.

In any case, it is worth giving the investigated parameters of the authors’ two models:

In the recent admixture model, tH was set to 4,500 generations ago (112.5 kya, Li and Durbin 2011), and tN was set to 12,000 generations ago (300 kya, Green et al. 2010). The tGF parameter was set to 2,000 generations (50 kya), and f was chosen to be 0.05. 

In the ancient structure model, T was varied between 12,000 to 32,000 generations ago, in steps of 2,000 generations. The intensity of ancient migration m was set to 4Nm = {0,1,…,10}. The non-African and Neanderthal populations split 12,000 generations ago (tN), and tH, the population split time between YRI and the non-African populations, was 4,500 generations ago.

I have a few observations:

• The population split between YRI and non-Africans is set at 112,500 years ago. This is most certainly inaccurate, since Yoruba possess mtDNA haplogroup L3 in common with Eurasians (age ~70ky), and they are also near completely within Y-haplogroup DE-YAP (which links them with Eurasians within a ~50ky timeframe). A split between YRI and non-Africans at 112,500 years ago is virtually impossible. Anapparent split at that time is plausible once we take into account that this number is inflated by admixture in Africa, and the YRI group may be partially descended partially from a West Eurasian-like population admixing with an older African substratum (early AMH or even older Africans).
• Archaic admixture in Africans has been little studied and there are several new studies in the works which will investigate it. For the time being, an initial admixture study, as well as the late persistence of archaic hominins in Africa appears to be consistent with a very late admixture event, rather than with a long-standing process of admixture between structured African populations.
• In the recent admixture model, the admixture is taken as both instantaneous (at tGF) and recent (50ky). The former assumption seems justified, but it is hard to believe in a model that would have Eurasians deviating from Africans 112,500 years ago and then waiting for 62,500 years to admix with Neandertals. Neandertals began to be neighbors of modern humans from before 100 thousand years in the Levant, and pre-50ky Neandertals such as Kebara are already modern-like, as is Vindija; the latter’s deviation towards modern humans is critical because it highlights the very real possibility that the ancient Neandertal genome as currently reconstructed may be in fact partially modern human.

I really don’t see why we the two models should differ qualitatively: a postulated abrupt (instantaneous) admixture event with Neandertals (despite the fact that modern humans and Neandertals were clearly neighbors for close to 100 thousand years) vs. a long-standing process of admixture in Africa.

To conclude, the new study is to be applauded for trying to evaluate different schemes for reaching the same observed D-statistics, but I would not throw the African structure hypothesis out the window quite yet.

Mol Biol Evol (2012) doi: 10.1093/molbev/mss117 

Ancient structure in Africa unlikely to explain Neanderthal and non-African genetic similarity 

Melinda A. Yang et al. 

Neanderthals have been shown to share more genetic variants with present-day non-Africans than Africans. Recent admixture between Neanderthals and modern humans outside of Africa was proposed as the most parsimonious explanation for this observation. However, the hypothesis of ancient population structure within Africa could not be ruled out as an alternative explanation. We use simulations to test whether the site frequency spectrum, conditioned on a derived Neanderthal and an ancestral Yoruba (African) nucleotide (the doubly conditioned site-frequency spectrum, dcfs), can distinguish between models that assume recent admixture or ancient population structure. We compare the simulations to the dcfs calculated from data taken from populations of European, Chinese, and Japanese descent in the Complete Genomics Diversity Panel. Simulations under a variety of plausible demographic parameters were used to examine the shape of the dcfs for both models. The observed shape of the dcfs cannot be explained by any set of parameter values used in the simulations of the ancient structure model. The dcfs simulations for the recent admixture model provide a good fit to the observed dcfs for non-Africans, thereby supporting the hypothesis that recent admixture with Neanderthals accounts for the greater similarity of Neanderthals to non-Africans than Africans. 

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