Archive for the ‘Humans’ Category

The future for human evolution

June 25, 2013

The future of human evolution is secure as we develop into more robust species.

From The Onion:

Image of Mollusca

ANN ARBOR, MI—In a breakthrough study that researchers say adds important insight into the evolution of Homo sapiens, scientists at the University of Michigan confirmed Thursday that human beings are slowly evolving into mollusks. “Evidence shows that modern humans emerged on the evolutionary timeline about 200,000 years ago, developed into the highly evolved hominids of today, and are now transforming into soft-bodied invertebrates,” said the study’s lead author Dr. Mitch Keneally, adding humans have already started turning into snails, slugs, and octopi, evidenced by their increasingly amorphous figures. “Over the next 1,000 years, we’re going to see people developing gills, a hard protective shell around their torsos, and a large, muscular foot in their dorsal region that will help with locomotion and mucus secretion. The world is changing rapidly, and those who can’t filter seawater aren’t going to be able to survive.” Scientists added that the evolutionary trajectory isn’t all that surprising considering that mollusks themselves descended from monkeys just 5,000 years ago.

Coping with climate change drove innovation

June 18, 2013

When and how innovation occurs sometimes seems random and the corporate world has long pursued the creation of “environments” in which innovation can flourish. And while the very definition of what counts as innovation can be debated, it seems to me that it is a changing environment rather than a static environment which is a key ingredient. And it could well be that the greater the change to be handled then the very necessity of coping with that change could be the “mother of all innovation”.

I suspect that some of the most fundamental innovations have been driven by the need not just to survive but also to thrive in “rapidly” changing and threatening environments. And climate change where “rapid” would mean several hundred if not thousands of years would also have been a powerful driver. One advantage in the stone age would have been that humans would have focused on coping with the change as it unfolded and not wasted too much effort in trying to control the climate.

A new paper addresses how climate change could have driven innovation in the stone age centered around the discovery and establishment of new refuges.

Ziegler, M. et al. Development of Middle Stone Age innovation linked to rapid climate changeNature Communications 4, Article number: 1905.

Abstract: The development of modernity in early human populations has been linked to pulsed phases of technological and behavioural innovation within the Middle Stone Age of South Africa. However, the trigger for these intermittent pulses of technological innovation is an enigma. Here we show that, contrary to some previous studies, the occurrence of innovation was tightly linked to abrupt climate change. Major innovational pulses occurred at times when South African climate changed rapidly towards more humid conditions, while northern sub-Saharan Africa experienced widespread droughts, as the Northern Hemisphere entered phases of extreme cooling. These millennial-scale teleconnections resulted from the bipolar seesaw behaviour of the Atlantic Ocean related to changes in the ocean circulation. These conditions led to humid pulses in South Africa and potentially to the creation of favourable environmental conditions. This strongly implies that innovational pulses of early modern human behaviour were climatically influenced and linked to the adoption of refugia.

PhysOrg reviews the paper:

According to a study by the Universitat Autònoma de Barcelona, the University of Cardiff and the Natural History Museum in London, technological innovation during the Stone Age occurred in fits and starts and was climate-driven. Abrupt changes in rainfall in South Africa 40,000 to 80,000 years ago triggered the development of technologies for finding refuge and the behaviour of modern humans. This study was recently published in Nature Communications.

Archaeological and genetic evidence suggests that modern humans (the modern form of Homo sapiens, our species) originated in Africa during the Stone Age, between 30,000 and 280,000 years ago. The latest  in southern Africa have shown that technological innovation, linked to the emergence of culture and modern behaviour, took place abruptly: the beginnings of symbolic expression, the making of tools from stone and bone, jewellery or the first agricultural settlements.

An international team of researchers has linked these pulses of innovation to the climate that prevailed in sub-Saharan Africa in that period.

Over the last million years the  has varied between  (with great masses of ice covering the continents in the northern hemisphere) and interglacial periods, with changes approximately every 100,000 years. But within these long periods there have been abrupt climate changes, sometimes happening in the space of just a few decades, with variations of up to 10ºC in the average temperature in the polar regions caused by changes in the Atlantic . These changes affected rainfall in southern Africa.

The researchers have pieced together how  varied in southern Africa over the last 100,000 years, by analysing  deposits at the edge of the continent, where every millimetre of  corresponds to 25 years of sedimentation. The ratio of iron (dissolved from the rocks by the water during the rains) to potassium (present in arid soils) in each of the millimetre layers is a record of the sediment carried by rivers and therefore of the rainfall throughout the whole period.

The reconstruction of the rainfall over 100,000 years shows a series of spikes that occurred between 40,000 and 80,000 years ago. These spikes show rainfall levels rising sharply over just a few decades, and falling off again soon afterwards, in a matter of centuries. This research has shown that the climate changes coincided with increases in population, activity and production of technology on the part of our ancestors, as seen in the archaeological records. In turn, the end of certain stone tool industries of the period coincides with the onset of a new, drier climate.

The findings confirm one of the principal models of Palaeolithic cultural evolution, which correlates technological innovation with the adoption of new refuges and with a resulting increase in population and social networks. For these researchers, the bursts of demographic expansion caused by climate change in southern Africa were probably key factors in the origin of modern humans’ behaviour in Africa, and in the dispersal of Homo sapiens from his ancestral home.

 

When this interglacial ends ….

June 7, 2013

This interglacial will end.

It may take another 100 years or 5,000 or it may already have ended. From whenever the end is reckoned  it could take about 4,000 years for full glacial conditions to set in.

interglacials

This interglacial will end

The ice sheets will advance again. New land will be exposed as sea levels fall – up to 120m.

The land mass of the world with the reduced sea levels might look like this (http://www.ngdc.noaa.gov/mgg/topo/globega2.html:

world map ice age image National Geophysical Data Center at NOAA

world map ice age image National Geophysical Data Center at NOAA

Geography will change. Islands will expand. Some seas will disappear as water gets locked up in the expanding ice sheets.  Greenland will expand. Siberia will connect to North America again. The United Kingdom will once again rejoin the continent. Indonesia and Australia will be extremely close. Japan will no longer be islands. The Baltic Sea will not exist. The Persian Gulf will disappear. Across the world coastlines will be “pushed out”. Ancient coastal city sites – long submerged – will reappear. The ice sheets will expand and will drastically reduce populations above 55 °N. The global population would have stabilised and may even fall. Populations will migrate. Nation states will  see their boundaries changing – physically not just by war. No doubt there will be new human conflicts as populations shift – though the shifts will be over hundreds of years and quite gradual in our terms. Average global temperatures will be about 2 – 4°C colder than today.

But this time the ice sheets will not stop humans from utilising the resources under some of the ice sheets. As during the last glacial period, human innovation and engineering will flourish and reach new heights as the challenges are met. New science and new technologies will appear. Art will take new forms. A new wave of exploration will occur – this time into space. And through all of this our energy needs will increase.

Time line of prehistoric inventions (pdf)

But it is the availability of abundant energy which will be the deciding factor, which allows growth to continue and which allows the continued  improvement of the human condition. And this energy will primarily be fossil energy and nuclear energy.  It will be nuclear energy for large central plants (> 1000 MW), fossil energy (coal, and gas) for medium sized plants (100 – 1000 MW)  and gas for municipal and domestic applications. Transportation will – largely as now – be electric or oil-based though the proportion of electric (charged from “cheap” nuclear power) vehicles will increase. Solar and wind and wave and tidal power will have their little place but will – as now – be of small impact.

It is fossil and nuclear power which will allow humanity to meet these new challenges. They will be a necessity for humans to flourish. Carbon dioxide emissions – as now – will be irrelevant. It is in the development of small nuclear, energy storage and more efficient gas- winning and utilisation that we should be concentrating.

Future human evolution will be selection by deselection

June 6, 2013

io9 carries  a look at how science fiction treats evolution :The most ludicrous depictions of evolution in science fiction history.

Of course this begs the question as to how humans are likely to evolve over the coming generations?

Humans and chimpanzees ancestors split some 7-8 million years ago and it took some 350,000 generations after that divergence for evolution by natural selection to produce anatomically modern humans (AMH). (This of course raises the question as to how chimpanzee evolution proceeded to reach modern chimpanzees while humans were developing into homo sapiens?).

It has been only about 10,000 generations since AMH appeared and only some 6,000 generations or so since modern humans left Africa. A very short time in evolutionary terms yet in this period humans have evolved to exhibit the various races of man that exist today. This differentiation is primarily superficial and all humans existing are capable of mating and producing viable offspring with each other. In theory humans existing today would also be compatible and – in the main – capable of mating with the humans of 6,000 generations ago. In practice a meeting of modern humans with those from 120,000 years ago would be an exaggerated replica of modern man meeting with isolated tribes in the 20th century. These isolated branches of humanity generally had lower levels of immunity to the bacteria carried by their distant cousins and were ravaged by disease after such encounters. The bacteria we carry are probably greatly different to those that humans carried at the dawn of anatomically modern humans. Probably no such meeting or mating would be very successful and one or both would probably succumb to disease brought on by the other’s bacteria. Nevertheless the genomes of the two – even after 6,000 generations – would  not be so very different and probably still be compatible. In any primate species a generational distance of over 20,000 between individuals will probably disqualify any theoretical possibility of successful mating.

(more…)

The next 100,000 years

June 1, 2013

In my other blog I try to address the life and times of the last 6,000 generations but trying to look forward to the next 6,000 is a fascinating thought experiment.

I was looking at the history of glacials and interglacials and just thinking that it was was terribly “unfair” that while I could imagine the future to my mind’s content, I could never know it. At least for even the distant past, we can look at surviving clues and by the logic that the past must have led to the present we can fill in the gaps and imagine what must have happened. The present constrains the past and helps to keep the imagination within narrow bounds. But for the future, the present  provides a starting point  and natural laws must also constrain any development of an unfolding future. But there are more natural laws we don’t know about than we do. And we haven’t a clue about all that we don’t know that we don’t know.

But I am still free to imagine what the next 100,000 years may bring.

As best we can judge, interglacials (defined as being when temperatures are higher than or equal to those at present)  have lasted upto 28,000 years and some seem to have been as short as 4,000 years. However most seem to last around 13,000 years. This interglacial period will surely end – whether within a 1000 years or in 10,000 – and a new glacial period will ensue.

http://roperld.com/science/sealevelvstemperature.htm

interglacials

But the next glacial will be different for humans and primarily because we have access to “abundant energy” (mainly based on fossil fuels and nuclear energy).

(more…)

Shamans versus the witch-doctors: psychologists attack the psychiatrists

May 12, 2013

I have the clear perception that psychiatry has gone too far in trying to attribute all kinds of behaviour to being disabilities. The very influential American Psychiatry Association’s Diagnostic and Statistical Manual of Mental Disorders DSM-5 is soon to be released and even describes grief and temper tantrums as disabilities and yet will no longer recognise Asperger’s! And the psychiatrists have the fundamental concept that all such disabilities are susceptible to medication.

Equally, while I recognise the importance of human psychology as a discipline I am less than impressed by the psychology and behaviour of psychologists and especially the academic gyrations of social psychologists.

So this headline in today’s Guardian conjures up images of a pitched battle between shamans and witch-doctors. I distinguish here between shamans who rely on various secret “medicines” to cure the afflicted, while the witch-doctors are the ones who engage in secret rites to free the patients from the spirits who are haunting them. I suppose in this analogy that the psychiatrists are the shamans and the psychologists are the witch-doctors. But the bottom line of course seems to be that psychologists wantb to adjust behaviour by adjusting other behaviour, and they feel threatened by the psychiatrists’ concept that all unwanted behaviour can be medicated away. The pharmaceutical industry – needless to say – tends to support the psychiatrists (what else?).

The GuardianPsychiatrists under fire in mental health battle

British Psychological Society to launch attack on rival profession, casting doubt on biomedical model of mental illness.

There is no scientific evidence that psychiatric diagnoses such as schizophrenia and bipolar disorder are valid or useful, according to the leading body representing Britain’s clinical psychologists.

In a groundbreaking move that has already prompted a fierce backlash from psychiatrists, the British Psychological Society’s division of clinical psychology (DCP) will on Monday issue a statement declaring that, given the lack of evidence, it is time for a “paradigm shift” in how the issues of mental health are understood. The statement effectively casts doubt on psychiatry’s predominantly biomedical model of mental distress – the idea that people are suffering from illnesses that are treatable by doctors using drugs. The DCP said its decision to speak out “reflects fundamental concerns about the development, personal impact and core assumptions of the (diagnosis) systems”, used by psychiatry.

Dr. Lucy Johnstone, a consultant clinical psychologist who helped draw up the DCP’s statement, said it was unhelpful to see mental health issues as illnesses with biological causes.

“On the contrary, there is now overwhelming evidence that people break down as a result of a complex mix of social and psychological circumstances – bereavement and loss, poverty and discrimination, trauma and abuse,” Johnstone said. The provocative statement by the DCP has been timed to come out shortly before the release of DSM-5, the fifth edition of the American Psychiatry Association’s Diagnostic and Statistical Manual of Mental Disorders. ….

…… The writer Oliver James, who trained as a clinical psychologist, welcomed the DCP’s decision to speak out against psychiatric diagnosis and stressed the need to move away from a biomedical model of mental distress to one that examined societal and personal factors.

Writing in today’s Observer, James declares: “We need fundamental changes in how our society is organised to give parents the best chance of meeting the needs of children and to prevent the amount of adult adversity.”

But Professor Sir Simon Wessely, a member of the Royal College of Psychiatrists and chair of psychological medicine at King’s College London, said it was wrong to suggest psychiatry was focused only on the biological causes of mental distress. And in an accompanying Observerarticle he defends the need to create classification systems for mental disorder.

“A classification system is like a map,” Wessely explains. “And just as any map is only provisional, ready to be changed as the landscape changes, so does classification.”

We were lowly scavengers long before we became noble hunter-gatherers

May 10, 2013

There has always been an aura of romance about our ancient hunter-gatherer forbears. The term “noble savage” ( “bon sauvage”) only dates back to 1672 but the concept gained ground in the 18th and 19th centuries and the idea of “nature’s gentlemen” flourished in the sentimentality of that time. Jean M Auel’s hugely successful Earths Children series also paints a picture of rather noble hunter-gatherers. Hunters are of course intrinsically heroic and appending “gatherers” to their description does not take too much away. The heroic stature is only dissipated when we become fully settled agriculturists – mere farmers – in the Holocene. Farmer’s don’t conjure up images of nobility and heroism and of course when humans became traders they also get greed and deviousness added to their image.

But there is no perceived nobility or honor in scavenging. It is the image of the hyena versus that of the lion. But long before we became hunter-gatherers we were scroungers and scavengers. New archaeological findings indicates that we were hunter-scavengers some 2 million years ago. And we were scavengers before that and scroungers when we first split from the chimps.

Ferraro JV, Plummer TW, Pobiner BL, Oliver JS, Bishop LC, et al. (2013) Earliest Archaeological Evidence of Persistent Hominin Carnivory. PLoS ONE 8(4): e62174. doi:10.1371/journal.pone.0062174

My imagined time-line for the various phases of human development then becomes:

  • 8 million YBP           Human Chimpanzee divergence – Scroungers
  • 4 million YBP           Bipedalism – Scavengers
  • 2 million YBP           Stone tools – Hunter-scavengers
  • 600,000 YBP          Archaic Human – Neanderthal divergence
  • 200,000 YBP          Hunting teams, herd followers  Hunter-nomads
  • 60,000    YBP          Semi-permanent dwellings, Hunter-gatherers
  • 11,500     YBP          Settled agriculture Farmers
  • 5,000       YBP          Mercantile expansions Merchant-soldiers

Monkeys – except the top monkey – switch behaviour to conform to local customs

April 29, 2013

Where humans are in a subordinate position in a new society (new immigrants for example) they usually conform to avoid attracting attention which could be dangerous. They observe, they copy behaviour to try to fit in and thereby ensure their own security in the new environment. All driven no doubt by the instinct to survive. But a conquering human does not bother to conform to local customs – he imposes his own. All humans are clearly capable of both types of behaviour. Whether to conform or not is then entirely dependent upon the individual’s position in the society he finds himself in.

And monkeys are – it seems – no different.

I suspect this holds true for many more species than just humans and primates and am a little surprised that the researchers are surprised at this behaviour.

A new paper: E. van de Waal, C. Borgeaud, A. Whiten. Potent Social Learning and Conformity Shape a Wild Primate’s Foraging DecisionsScience, 2013; 340 (6131): 483 DOI:10.1126/science.1232769

From University of St. Andrews press release:

Noha group feeding on pink corn

Noha group feeding on pink corn

….. In the initial study, the researchers provided each of two groups of wild monkeys with a box of maize corn dyed pink and another dyed blue. The blue corn was made to taste repulsive and the monkeys soon learned to eat only pink corn. Two other groups were trained in this way to eat only blue corn. A new generation of infants were later offered both colours of food – neither tasting badly – and the adult monkeys present appeared to remember which colour they had previously preferred. Almost every infant copied the rest of the group, eating only the one preferred colour of corn.

The crucial discovery came when males began to migrate between groups during the mating season. The researchers found that of the ten males who moved to groups eating a different coloured corn to the one they were used to, all but one switched to the new local norm immediately.

The one monkey who did not switch, was the top ranking in his new group who appeared unconcerned about adopting local behavior.

Dr van de Waal conducted the field experiments at the Inkawu Vervet Project in the Mawana private game reserve in South Africa. She became familiar with all 109 monkeys, making it possible for her to document the behaviour of the males who migrated to new groups.

She said, “The willingness of the immigrant males to adopt the local preference of their new groups surprised us all. The copying behaviour of both the new, naïve infants and the migrating males reveals the potency and importance of social learning in these wild primates, extending even to the conformity we know so well in humans.”

Commenting on the research, leading primatologist Professor Frans de Waal, of the Yerkes Primate Center of Emory University, said that the study “is one of the few successful field experiments on cultural transmission to date, and a remarkably elegant one at that.”

Abstract: Conformity to local behavioral norms reflects the pervading role of culture in human life. Laboratory experiments have begun to suggest a role for conformity in animal social learning, but evidence from the wild remains circumstantial. Here, we show experimentally that wild vervet monkeys will abandon personal foraging preferences in favor of group norms new to them. Groups first learned to avoid the bitter-tasting alternative of two foods. Presentations of these options untreated months later revealed that all new infants naïve to the foods adopted maternal preferences. Males who migrated between groups where the alternative food was eaten switched to the new local norm. Such powerful effects of social learning represent a more potent force than hitherto recognized in shaping group differences among wild animals.

Composition of exhaust gases from humans and from fossil fuels

April 13, 2013

It occurred to me when carrying out some combustion calculations that what humans breathe out is pretty close to the flue gas from a gas-fired, gas turbine combined cycle plant.

In a gas turbine combustion chamber, fuel is burned typically at an excess air level of about 200% (the amount of oxygen available in the combustion air compared to that which is needed for complete oxidation of the fuel). This means that about one third of the oxygen available is used and converted to carbon dioxide and water while about 2/3ds just passes through (i.e of the 21% oxygen in air, about 6-7% is “consumed” and about 14 -15% passes through unused). In coal-fired plants the excess air levels are usually only about 25% which leads to about 15 -16% of the incoming 21% oxygen being consumed with about 5% passing through. The amount of oxygen actually consumed depends on the fuel composition and the oxygen demands of the elements which are oxidised during the combustion process. Carbon, hydrogen and sulphur (giving CO2, H2O and SO2) are the main oxygen consumers. All the other constituents of air pass through – heated up of course – but otherwise unchanged. Minute quantities of the fuel- nitrogen and the nitrogen in the incoming air can – depending upon the combustion temperature – be “fixed” to create the nitrogen oxides – nitrous oxide (N2O) and nitrogen dioxide (N2O). The higher the combustion temperature the greater the “fixing”. Too low a combustion temperature – for example with very wet fuels and bio-mass – can give “incomplete combustion” with some carbon monoxide (CO) and even some dioxins and hydrocarbons with a particularly poor combustion process. Internal combustion petrol engines essentially run at stoichiometric conditions (zero excess air) and there is no oxygen in the exhaust. However combustion is never quite complete and around 1% carbon monoxide is usually present (which is why suicide by exhaust fumes becomes possible). Diesel engines on the other hand have 10% oxygen in the exhaust when idling and this reduces to 1 or 2% when fully loaded.

All fuels essentially contain carbon and hydrogen as the main energy releasing elements when oxidised. Most industrial combustion processes happen fast and speed of combustion – which is desirable for complete combustion – has to be tempered by the need to keep temperatures at levels which can be handled by the materials used. The human use of the same elements of carbon and hydrogen for the release of energy however is by a relatively slow oxidation processes. Not all the water produced leaves the human body with our expelled breath since some part of it leaves in liquid form with urine. But from the composition of the waste gas we breathe out it seems that the carbon/hydrogen ratios in our food intake cannot be so very different to the natural gas burned in gas turbines (and not very surprising considering that plant-life is the ultimate source of both).

exhaust gas compositions

 

Since human exhaust gases emit the same concentration of carbon dioxide as gas turbine, combined cycle power plant perhaps we should penalise every human as well?