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When the encyclopedia in your pocket is wired into your brain

January 20, 2019

All human knowledge is not, yet, available on the web. All the knowledge which is available on the web is not, yet, available to each of us. But all that is available on the web is already available to each of us who has a connected smart phone in a pocket. With every connected smart phone there is an encyclopedia in a pocket.

But using such an encyclopedia is not, yet, instantaneous. It is not yet a part of your brain. It is not just the choice of browser or search engine (e.g. Google) or the repository (e.g.Wikipedia). You still have to search the web. You still have to ask the right question. You still have to discard the advertisements and the fake news and select the relevant information. It takes a little time. By the time you find the right answer the conversation may have moved on to another topic, such that presenting the information you found in your pocket may be embarrassingly irrelevant.

Nevertheless, everyone with a connected smart phone now has an encyclopedia in their pocket. And, I would guess, this encyclopedia will be implanted and connected to the brain within the next 50 years.

We are already in the age of implants.

Currently, implants are being used in many different parts of the body for various applications such as orthopaedics, pacemakers, cardiovascular stents, defibrillators, neural prosthetics or as drug delivery systems. Concurrent with the increased life span in today’s world, the number of age-related diseases has also increased. Hence, the need for new treatments, implants, prostheses and long-term pharmaceutical usage as well as the need for prolonging the life span of the current techniques has increased. 

Implants where thoughts can be used to control computers are already with us. Brain-computer interfaces (BCI’s) which were first thought of in the 1970s are now with us to stay.

image from Frontiersin.org

When drone warfare emerged, pilots could, for the first time, sit in an office in the U.S. and drop bombs in the Middle East. Now, one pilot can do it all, just using their mind — no hands required.

Earlier this month, DARPA, the military’s research division, unveiled a project that it had been working on since 2015: technology that grants one person the ability to pilot multiple planes and drones with their mind.

“As of today, signals from the brain can be used to command and control … not just one aircraft but three simultaneous types of aircraft,” Justin Sanchez, director of DARPA’s Biological Technologies Office, said, according to Defense One.

….. Back in 2016, a volunteer equipped with a brain-computer interface (BCI) was able to pilot an aircraft in a flight simulator while keeping two other planes in formation — all using just his thoughts, ….. In 2017, Copeland was able to steer a plane through another simulation, this time receiving haptic feedback — if the plane needed to be steered in a certain direction, Copeland’s neural implant would create a tingling sensation in his hands.

We cannot yet, at will, without noticeable delay, mentally call for and access some particular information from the entire store of human knowledge.  But it is no longer science fiction to imagine people with an implant which has all the abilities of a mobile, smart phone. It will be an implant where the input/output interface would no longer require the use of fingers or the reading of a physical screen. Your thoughts (and perhaps also sub-vocalisations) would be sufficient to trigger the appropriate questions to the web. The answers would be projected onto your eyes or enter your brain subliminally. Humans would have to become far more practiced not only at distinguishing between interfacing with the external world and internally connecting with the web, but also with mental multi-tasking in a way never required before.

Maybe not in 10 years but surely within 50.

 

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Posted in Development, Evolution | 1 Comment »

And then came counting

August 25, 2018

Origins of human cognitive development go back a lot longer than was once thought. Our first bipedal ancestors who came down from the trees more than 5 million years ago, had  already some concept of “more” and “less” and  perhaps even of rudimentary numbers upto 3 (as rhesus monkeys have today). Genetic analysis of ancient bones is showing that the origin and development of modern humans needs to be taking the Neanderthals and the Denisovans into account and perhaps has to go back at least to the time of a common ancestor from over 1 million years ago. Just considering the last 200,000 years is no longer enough.

I have no doubt that the mastery of fire, the eating of cooked meat, the growth of the brain and, above all, the increased need for cooperation were interconnected and drove human cognitive development. Whether developments happened in one place and spread or happened at many places, perhaps at many times, will always be a matter of speculation. But it is not so difficult to come up with a not implausible time-line of the key developments which gave us first counting and then tallying and arithmetic and geometry and now complex number theory. The oldest evidence we have of counting are tally-sticks from over 50,000 years ago. But counting surely started long before that.

Related:

What led humans to counting and when?

The origins of base 60

 

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Invasive species and opposing natural selction

June 1, 2018

Sweden is planning to declare the mouflon to be an invasive species. It would then be politically acceptable to eradicate the species.

“The mouflon (Ovis orientalis orientalis group) is a subspecies group of the wild sheep (Ovis orientalis). Populations of O. orientalis can be partitioned into the mouflons (orientalis group) and the urials (vignei group). The mouflon is thought to be one of the two ancestors for all modern domestic sheep breeds.” – Wikipedia

 

I find much of “conservation” sanctimonious, hypocritical and illogical.

 

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Extinction is normal

April 17, 2018

Living things evolve, dead things can be remembered but extinction is normal.

I have no objection to expressions of regret, but I find the hand-wringing and sanctimonious claptrap about the extinction of species, languages and cultures illogical and without thought. I don’t miss the dodo or any of the dinosaurs. I don’t miss Latin or Sanskrit (even though I had to sit through boring lessons in both). It is only a natural course of development that isolated Amazonian tribes have disappeared as their members have joined the rest of the world. I don’t miss the cannibalistic cultures which have disappeared. The recent splurge of nonsense about the “death of the last known male, northern white rhino” was a case in point. It may be a matter of some regret that this particular individual died a natural death, but the end of an unfit sub-species of rhino is not an event requiring the mawkish sentimentality that flooded the media.

Extinction is normal.

Species evolve to survive or they go extinct. Languages evolve and they die when they are of no use to anyone anymore. Cultures evolve and merge with other cultures or they try to remain separate as a distinct, (often racial) identity by isolation and inevitably they die out. The cultures that disappear don’t survive because they are not viable in the world they live in. Regret is one thing, but trying to artificially protect non-viable species, languages or cultures or peoples by putting them in a “zoo” is mawkish and irrational and, ultimately, unethical. Keeping backward tribes isolated to “preserve” their cultures and freezing them into backwardness (by preventing them from merging or being absorbed by the world) is immoral. Freezing individuals from unfit species in a zoo, and neither helping them to evolve nor allowing the species to go extinct, is immoral. Preserving dead languages is of academic interest and does not prevent the extinction of languages which no longer serve a useful purpose.

To the best of our knowledge there are about 7,000 languages recognised today. Depending upon when language began (between 50,000 and 200,000 years ago) between 90 and 99% of all languages are now extinct. Written languages are much younger of course. An extinct language is a matter of history. Some languages evolved and produced versions still in use today. Others did not. We know about some of these because they developed writing and left some records which have survived. Languages die a natural death when they stop being used. Of course there is nothing wrong in speakers of dying languages trying to revitalise them. Governments have sometimes tried to promote particular languages (French, Hindi), and sometimes to suppress some (Welsh, Sami). Languages have been invented (Esperanto or Klingon). Most of these attempts of artificially creating, protecting or suppressing language are futile. The ultimate arbiter of language (and of grammar and of spelling) is usage.  The real question should not be whether a language is “endangered” and should be protected but whether a language serves any useful purpose. If it does, it will survive. If it does not, it should not survive. Endangered languages should be recorded for history and allowed to die in peace.

We don’t know how many species are alive today. Estimates have ranged from 10 million to 14 million, of which over 86 percent have not yet been described. A 2016 study even concludes that Earth currently has 1 trillion species. Whatever the actual number, what is known is that over 99% of all species that ever existed are now extinct. By the time a failing species is formally considered to be endangered, it is almost irrelevant to the ecological system it is embedded in. Tigers, as an example, are restricted only to areas of captivity (whether zoos or reserves). Even in some reserves where they are nominally free, the species is of no great significance to the bio-system. A species may well be going extinct because it is losing habitat to humans, but that in itself is a failure of that species. Some species are adapting to man, but where conservationists intervene to “protect” species they always do so by freezing the species into some form of captivity. They never try to help that species to adapt genetically to survive in its new environment. This form of conservation may be emotionally satisfying for humans but is of little consequence in the sustainable survival of the endangered species. Evolution produces far more failed species than successful ones. The detritus of evolution needs to be cleaned out from time to time. A mass extinction is one way to muck out the evolutionary stables. Currently there are too many species surviving and around 30% probably need to be washed away into extinction.

As with language and species there is much energy and misguided thinking expended in the protection of “indigenous peoples” and outdated, non-viable cultures. Much of this “protection” is about “freezing” these humans and their cultures into unsustainable conditions in what are effectively human zoos or reserves.

There are approximately 370 million Indigenous people in the world, belonging to 5,000 different groups, in 90 countries worldwide. Indigenous people live in every region of the world, but about 70% of them live in Asia.

The long term survival of tribes and indigenous peoples is by them joining or being absorbed by the mainstream or of reaching a critical mass such that they can have an autonomous survival. Genetic isolation (or genetic purity as practiced by some groups) is not sustainable in the long term. The Sentinelese are still apparently in the “stone-age” and both isolated and captive. Is it better (for whom?) to allow them to remain isolated and doomed or to bring them into the mainstream which would effectively eliminate them as a separate but backward culture?

Extinction is normal for peoples, languages, cultures and for species. To struggle against extinction is just a part of survival and also normal. But when extinction does occur, it may be a matter of regret and even of sorrow, but it is normal and morally neutral. But “conservation” by freezing language or culture or species or peoples into a “failed” condition is immoral.

Related:

Evolution is indifferent to species survival

Conservation denies tigers a future as a species

There was no biodiversity to begin with

 

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Life exists as a succession of identities

November 18, 2017

Life is an abstract concept manifested as living things. The thread of life has no discernible beginning.

Life – to be life – must be manifested in an entity capable of reproduction. The elements displaying life either continue or come to an end. The thread is carried as a possibility by every sperm and every egg but the sperm and egg cannot themselves reproduce. Most of these possibilities come to an end before the two combine. If – and only if – a sperm and egg do combine, then life continues as, and within, a unique identity created by that combination. It is the creation of the identity – at conception – which continues life. About one in 300 billion sperm survives to combine with about one in 200 eggs to create an identity. It is a unique genetic identity. That identity, first as a fetus may end before birth. Or it may continue after birth as a child. It may grow to be an adult human and give rise to further sperm or eggs before itself coming to an end. When that identity qualifies to be considered a human entity and protected by society is a choice for the societies and the individuals concerned. Most societies start assigning the identity some rights and protections before birth but only after about 20 weeks of life as a fetus.

There is little doubt, however, that a unique genetic identity is created at conception, whether in a test tube or in a womb. At what stage of development that identity achieves consciousness and then self-awareness is not certain but almost certainly only after a rudimentary brain has formed. That would be some weeks after conception but probably some little time before birth. At what point that identity is to be afforded legal “rights” is then a matter for the surrounding society to determine.

Until the identity reaches birth – whether by natural or by artificial means – it has no options and no choices to exercise. Whether self-aware or not, its existence is in the gift and the power of others. It starts acquiring choices and freedoms of action only after birth, as allowed or constrained by its own development and the rules of the society it finds itself in.

Life then only exists as a succession of identities.

To trace the beginning of life would require going back from identity to identity to the specific cells some 3.7 billion years ago. A collection of sperm and eggs may contain the elements for life to continue but do not in themselves constitute life. The beginning of an identity is not the beginning of life. But the act of conception brings a unique identity into being and it is surely the beginning of a specific new life.

Life may be continuous as a concept but can only be realised and manifested as a succession of unique, discrete identities.

 

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Evolution is indifferent to species survival

November 11, 2017

 

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Early hominins left Africa 6 million years ago

September 3, 2017

A foot print found in Crete is probably that of an early hominid and was made 5.7 million years ago.

The single Out-of-Africa theory sometime around 70,000 years ago is already obsolete. It was more likely to have been multiple hominin crossings out of Africa into both Europe and Asia. The expansion of homo sapiens sapiens is more likely to have been in  at least two waves out of Africarabia.  Homo erectus appeared around 2 million years ago while homo sapiens appeared about 1 million years ago.  Homo sapiens sapiens then split from homo sapiens neanderthalensis around 600,000 years ago. So the footprint found is that of a human ancestor after the split with chimpanzees (c. 8-9 million years ago), after the beginning of bipedalism but well before homo erectus appeared.

image from physorg

The paper is

Gerard D. Gierlińskia et al., Possible hominin footprints from the late Miocene (c. 5.7 Ma) of Crete? Proceedings of the Geologists’ Association, 2017 DOI: 10.1016/j.pgeola.2017.07.006

As the Uppsala University  press release puts it:

….. Ever since the discovery of fossils of Australopithecus in South and East Africa during the middle years of the 20th century, the origin of the human lineage has been thought to lie in Africa. More recent fossil discoveries in the same region, including the iconic 3.7 million year old Laetoli footprints from Tanzania which show human-like feet and upright locomotion, have cemented the idea that hominins (early members of the human lineage) not only originated in Africa but remained isolated there for several million years before dispersing to Europe and Asia. The discovery of approximately 5.7 million year old human-like footprints from Crete, published online this week by an international team of researchers, overthrows this simple picture and suggests a more complex reality. …….

The new footprints, from Trachilos in western Crete, have an unmistakably human-like form. This is especially true of the toes. The big toe is similar to our own in shape, size and position; it is also associated with a distinct ‘ball’ on the sole, which is never present in apes. The sole of the foot is proportionately shorter than in the Laetoli prints, but it has the same general form. In short, the shape of the Trachilos prints indicates unambiguously that they belong to an early hominin, somewhat more primitive than the Laetoli trackmaker. They were made on a sandy seashore, possibly a small river delta, whereas the Laetoli tracks were made in volcanic ash. …….

…… During the time when the Trachilos footprints were made, a period known as the late Miocene, the Sahara Desert did not exist; savannah-like environments extended from North Africa up around the eastern Mediterranean. Furthermore, Crete had not yet detached from the Greek mainland. It is thus not difficult to see how early hominins could have ranged across south-east Europe and well as Africa, and left their footprints on a Mediterranean shore that would one day form part of the island of Crete.

‘This discovery challenges the established narrative of early human evolution head-on and is likely to generate a lot of debate. Whether the human origins research community will accept fossil footprints as conclusive evidence of the presence of hominins in the Miocene of Crete remains to be seen,’ says Per Ahlberg.

Abstract

We describe late Miocene tetrapod footprints (tracks) from the Trachilos locality in western Crete (Greece), which show hominin-like characteristics. They occur in an emergent horizon within an otherwise marginal marine succession of Messinian age (latest Miocene), dated to approximately 5.7 Ma (million years), just prior to the Messinian Salinity Crisis. The tracks indicate that the trackmaker lacked claws, and was bipedal, plantigrade, pentadactyl and strongly entaxonic. The impression of the large and non-divergent first digit (hallux) has a narrow neck and bulbous asymmetrical distal pad. The lateral digit impressions become progressively smaller so that the digital region as a whole is strongly asymmetrical. A large, rounded ball impression is associated with the hallux. Morphometric analysis shows the footprints to have outlines that are distinct from modern non-hominin primates and resemble those of hominins. The interpretation of these footprints is potentially controversial. The print morphology suggests that the trackmaker was a basal member of the clade Hominini, but as Crete is some distance outside the known geographical range of pre-Pleistocene hominins we must also entertain the possibility that they represent a hitherto unknown late Miocene primate that convergently evolved human-like foot anatomy.

 

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Manliness has more than halved in western men since 1973

July 26, 2017

There is a new paper, a meta-review, receiving much attention.

The manliness of western men has more than halved between 1973 and 2011. It reports a significant ongoing decline in sperm concentration and sperm counts of Western men. It seems that “between 1973 and 2011, the researchers found a 52.4 percent decline in perm concentration, and a 59.3 percent decline in total sperm count, among men from North America, Europe, Australia and New Zealand ….  In contrast, no significant decline was seen in South America, Asia and Africa.”

Being a meta-review this study does not shed light on the causes of this drastic decline in the manliness of western men. It speculates that this may be due to chemicals or lifestyle or smoking or obesity or pesticides or some other factor. This speculation is just speculation and smoking or pesticide use would have caused stronger effects in Asia. They are quite right, however, in not following the sheep and including global warming as a possible cause. However they seem to be ignoring some other relevant factors.

I am inclined to think that the decrease of manliness among western men sounds more like a psychological reaction to political trends. Western society just values “manliness” much less than it used to. So other factors which probably need to be considered include:

  1. the increase of gender ambiguity
  2. the decrease in men’s social status
  3. the decline of political leadership in the west,
  4. the spread of political indecisiveness,
  5. the decline of corporal punishment in schools,
  6. the decline of femininity

It stands to reason that if gender difference is eliminated then sperm count and concentration will also decline. It follows that eliminating gender difference will result in the elimination of reproduction and species extinction.

Hagai Levine et al. Temporal trends in sperm count: a systematic review and meta-regression analysis. Human Reproduction Update. DOI: 10.1093/humupd/dmx022

MedicalXpress writes:  ….. between 1973 and 2011, the researchers found a 52.4 percent decline in perm concentration, and a 59.3 percent decline in total sperm count, among men from North America, Europe, Australia and New Zealand ….  In contrast, no significant decline was seen in South America, Asia and Africa. ….. The study also indicates the rate of decline among Western men is not decreasing: the slope was steep and significant even when analysis was restricted to studies with sample collection between 1996 and 2011. ….. 

While declines in sperm count have been reported since 1992, the question has remained controversial because of limitations in past studies. However, the current study uses a broader scope and rigorous meta-regression methods, conservatively addresses the reliability of study estimates, and controls for factors that might help explain the decline such as age, abstinence time, and selection of the study population.

“Given the importance of sperm counts for male fertility and human health, this study is an urgent wake-up call for researchers and health authorities around the world to investigate the causes of the sharp ongoing drop in sperm count, with the goal of prevention,” said Dr. Hagai Levine, the lead author and Head of the Environmental Health Track at the Hebrew University-Hadassah Braun School of Public Health and Community Medicine, in the Hebrew University of Jerusalem’s Faculty of Medicine.

The findings have important public health implications. First, these data demonstrate that the proportion of men with sperm counts below the threshold for subfertility or infertility is increasing. Moreover, given the findings from recent studies that reduced sperm count is related to increased morbidity and mortality, the ongoing decline points to serious risks to male fertility and health.

“Decreasing sperm count has been of great concern since it was first reported twenty-five years ago. This definitive study shows, for the first time, that this decline is strong and continuing. The fact that the decline is seen in Western countries strongly suggests that chemicals in commerce are playing a causal role in this trend,” Dr. Shanna H Swan, a professor in the Department of Environmental Medicine and Public Health at the Icahn School of Medicine at Mount Sinai, New York.

While the current study did not examine causes of the observed declines, sperm count has previously been plausibly associated with environmental and lifestyle influences, including prenatal chemical exposure, adult pesticide exposure, smoking, stress and obesity. Therefore, sperm count may sensitively reflect the impact of the modern environment on male health across the lifespan and serve as a “canary in the coal mine” signaling broader risks to male health.

It also follows that western men pose less of a risk to women looking for promiscuity, but that western women who wish to have children have a better chance with men having a higher level of manliness.

 

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Posted in Behaviour, Evolution | 1 Comment »

Conservation denies tigers a future as a species

June 13, 2017

There are, it is thought, around 4,000 tigers still living in the “wild”. There may be as many as 8 – 9,000 in captivity (3,000 in China and perhaps 5,000 in the US). The tigers in captivity are in zoos and parks and are, in the US, often bred for “hunting”. Very few (< 100 perhaps) of those in captivity are returned to the “wild” every year. Breeding hybrid tigons and ligers once used to be very popular in zoos but less so now though it is still prevalent for entertainment purposes. The numbers are not very significant.

Tigers are magnificent animals and a cultural icon for humans. No doubt the sabre-toothed tiger was an even more magnificent creature. It is surely a matter of regret that they became extinct a long time ago. As a species they were replaced by others which were more suited to the changing world. If present-day tigers (considered endangered) were to become extinct, it would also be a matter of much regret. But I find the rationale for “conservation” efforts flawed and illogical. The WWF (which is close to being one of my least favourite organisations) writes in a typical woolly-headed, gushing style:

Yet they are more than just a magnificent animal – they are also crucial for the ecosystems in which they live. As top predators of the food chain, tigers keep populations of prey species in check, which in turn maintains the balance between herbivores and the vegetation upon which they feed. Balanced ecosystems are not only important for wildlife, but for people too – both locally, nationally and globally. People rely on forests, whether it is directly for their livelihoods or indirectly for food and products used in our daily lives. ……… Tigers not only protect the forest by maintaining ecological integrity, but also by bringing the highest levels of protection and investment to an area. Tigers are an “umbrella species” – meaning their conservation also conserves many other species in the same area. They are long-ranging and require vast amounts of habitat to survive; an adult male’s home range varies from 150 km2 – 1000 km2.

Tigers are endangered because their habitats are disappearing. That habitat loss is fundamentally irreversible. As a species they already have no significant role to play in the ecosystem prevailing. They have already become a redundant species biologically even if the concept of majestic tigers roaming wild forests still has a massive emotional impact on the selfish human psyche. Creating new tiger reserves – constrained in area by various means –  is little more than creating glorified zoos. They are just parks where the cages are a little bigger.  The tigers themselves are “frozen” into their current, unsuccessful, unsuitable, failed genetic state. They are doomed to continue unchanged and unchanging in a shrinking and ever more unsuitable habitat. There are no natural selection pressures (or artificial selection measures) in play which would make their descendants more capable of surviving in the new habitats due to changes that have already happened and have yet to come. This “conservation” is not about helping the tiger to survive by evolving but is only about freezing them into an increasingly untenable form. It is backwards looking and all about preserving failure.

I am even more convinced that traditional “conservation” is misguided and is done just to satisfy the emotional needs of humans, and not, in any way, forward-looking to help endangered species to adapt and survive into the future.

Fighting against species extinction is to deny evolution   – (ktwop – 2013)

So what then is the objection to – say – tigers becoming extinct which is not just an emotional reaction to the disappearance of a magnificent but anachronistic creature?  The bio-diversity argument is not very convincing and is of little relevance. To artificially keep an unsuccessful species alive in a specially protected environment has no genetic value. It increases the mis-match between the existing environment and the genetic profile needed to survive in that environment. In fact the biodiversity argument is only relevant for “life” in general and never for any particular species or group of species.  It can serve to maintain a very wide range of genetic material in the event of a catastrophe such that some form of life has a chance of continuing. But given a particular environment biodiversity in itself is of little value. …

…. All those species which succeed into the future will be those which continue to “evolve” and have the characteristics necessary to thrive within the world as it is being shaped and changed by the most successful species that ever lived (though we cannot be sure how far some particular species of dinosaur may have advanced). Putting a tiger into a zoo or a “protected” environment actually only preserves the tiger in an “unsuccessful” form in an artificial environment. Does this really count as “saving the species”? We might be of more use to the future of the tiger species if we intentionally bred them to find a new space in a changed world  – perhaps as urban tigers which can co-exist with man.

Smilodon image DinoAnimals.com

I’ll still make a donation to Project Tiger but that is about helping individuals to survive and has nothing to do with saving the species.

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Sherpas are genetically more efficient at using Oxygen

May 23, 2017

A new paper today confirms that Sherpas are genetically more efficient at using Oxygen. It is another example of an ethnic group where defining characteristics of the group are genetically inherited.

Horscroft, J et al. Metabolic basis to Sherpa altitude adaptation. PNAS; 22 May 2017; DOI: 10.1073/pnas.1700527114

EurekAlert: Sherpas have evolved to become superhuman mountain climbers, extremely efficient at producing the energy to power their bodies even when oxygen is scarce, suggests new research published today in the Proceedings of the National Academy of Sciences (PNAS). …..

When oxygen is scarce, the body is forced to work harder to ensure that the brain and muscles receive enough of this essential nutrient. One of the most commonly observed ways the body has of compensating for a lack of oxygen is to produce more red blood cells, which are responsible for carrying blood around the body to our organs. This makes the blood thicker, however, so it flows more slowly and is more likely to clog up blood vessels.

Mountain climbers are often exposed to low levels of oxygen, particularly at high altitudes. This is why they often have to take time during long ascents to acclimatise to their surroundings, giving the body enough time to adapt itself and prevent altitude sickness. In addition, they may take oxygen supplies to supplement the thin air.

Scientists have known for some time that people have different responses to high altitudes. While most climbers require additional oxygen to scale Mount Everest, whose peak is 8,848m above sea level, a handful of climbers have managed to do so without. Most notably, Sherpas, an ethnic group from the mountain regions of Nepal, are able to live at high altitude with no apparent consequences to their health – as a result, many act as guides to support expeditions in the Himalayas, and two Sherpas are known to have reached the summit of Everest an incredible 21 times.

Previous studies have suggested differences between Sherpas and people living in non-high altitude areas, known collectively as ‘lowlanders’, including fewer red blood cells in Sherpas at altitude, but higher levels of nitric oxide, a chemical that opens up blood vessels and keeps blood flowing.

Evidence suggests that the first humans were present on the Tibetan Plateau around 30,000 years ago, with the first permanent settlers appearing between 6,000-9,000 years ago. This raises the possibility that they have evolved to adapt to the extreme environment. This is supported by recent DNA studies, which have found clear genetic differences between Sherpa and Tibetan populations on the one hand and lowlanders on the other. Some of these differences were in their mitochondrial DNA – the genetic code that programmes mitochondria, the body’s ‘batteries’ that generate our energy.

To understand the biological differences between the Sherpas and lowlanders, a team of researchers led by scientists at the University of Cambridge followed two groups as they made a gradual ascent up to Everest Base Camp at an elevation of 5,300m.

The study was part of Xtreme Everest, a project that aims to improve outcomes for people who become critically ill by understanding how our bodies respond to the extreme altitude on the world’s highest mountain. This year marks 10 years since the group’s first expedition to Everest.

The lowlanders group comprised 10 investigators selected to operate the Everest Base Camp laboratory, where the mitochondrial studies were carried out by James Horscroft and Aleks Kotwica, two PhD students at the University of Cambridge. They took samples, including blood and muscle biopsies, in London to give a baseline measurement, then again when they first arrived at Base Camp and a third time after two months at Base Camp. These samples were compared with those taken from 15 Sherpas, all of whom were living in relatively low-lying areas, rather than being the ‘elite’ high altitude climbers. The Sherpas’ baseline measurements were taken at Kathmandu, Nepal.

The researchers found that even at baseline, the Sherpas’ mitochondria were more efficient at using oxygen to produce ATP, the energy that powers our bodies.

As predicted from genetic differences, they also found lower levels of fat oxidation in the Sherpas. Muscles have two ways to get energy – from sugars, such as glucose, or from burning fat (fat oxidation). The majority of the time we get our energy from the latter source; however, this is inefficient, so at times of physical stress, such as when exercising, we take our energy from sugars. The low levels of fat oxidation again suggest that the Sherpas are more efficient at generating energy.

The measurements taken at altitude rarely changed from the baseline measurement in the Sherpas, suggesting that they were born with such differences. However, for lowlanders, measurements tended to change after time spent at altitude, suggesting that their bodies were acclimatising and beginning to mimic the Sherpas’.

One of the key differences, however, was in phosphocreatine levels. Phosphocreatine is an energy reserve that acts as a buffer to help muscles contract when no ATP is present. In lowlanders, after two months at high altitude, phosphocreatine levels crash, whereas in Sherpas levels actually increase.

In addition, the team found that while levels of free radicals increase rapidly at high altitude, at least initially, levels in Sherpas are very low. Free radicals are molecules created by a lack of oxygen that can be potentially damaging to cells and tissue.

“Sherpas have spent thousands of years living at high altitudes, so it should be unsurprising that they have adapted to become more efficient at using oxygen and generating energy,” says Dr Andrew Murray from the University of Cambridge, the study’s senior author. “When those of us from lower-lying countries spend time at high altitude, our bodies adapt to some extent to become more ‘Sherpa-like’, but we are no match for their efficiency.” ……

Race is not a social construct as the politically correct would have me believe. Race is real and is a consequence of ancestry. Racial classification is fluid and changes but only over generational time. Sherpa genes help high-altitude living. There are West African genes which help sprinters, East African genes which are beneficial for long-distance runners, Scandinavian genes which predispose to diabetes 1 and Indian genes which predispose to diabetes 2.

And there are genes which predispose to high performance in IQ testing.

 

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Posted in Evolution, Genetics | Comments Off on Sherpas are genetically more efficient at using Oxygen

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