Wednesday, 30 May 2012

Climate change could seriously affect the water quality and quantity in the Indian rivers due to extreme events like floods and droughts, seawater intrusion and anthropogenic contamination, warn scientists

Syed Akbar
Hyderabad: Climate change could seriously affect the water
quality and quantity in the Indian rivers due to extreme events like
floods and droughts, seawater intrusion and anthropogenic
contamination, warn city scientists.

They feel that there is an urgent need of generation of new data and
aquifer modeling of river basins in India for proper understanding of
the effects of climate change on large water bodies. As part of the
drive, eminent earth and water scientists from around the world will
soon converge on the city-based National Geophysical Research
Institute (CSIR-NGRI) where they will gain a better understanding of
the evolution of these river systems, both in recent and geological
past.

According to NGRI senior scientist Dr S Masood Ahmad, “potential
effects of climate change on river basins indicate that construction
of dams or anthropogenic contamination on large river basins like
Godavari will require significant management intervention to protect
ecosystems and people, who are mainly dependent on these river basins.”

Stating that as many as 135 million people inhabit in the river basins
of Godavari and Krishna, Dr Masood Ahmad said the Krishna-Godavari
(K-G) and Kaveri basins present very fascinating examples of
hydrogeological and ecological settings. The process of precipitation,
recharge and storage as well as hydrodynamics of water flow of these
rivers remain quite ambiguous and require detailed investigations due
to the changing climate.

“Godavari, Krishna and Kaveri have experienced dramatic changes in
flow due to the construction of dams, anthropogenic contamination and
other development activities. However, the impact of climate change on
south Indian rivers is relatively less compared to the Himalayan
rivers like Ganges. Water discharge in south Indian rivers is
dependent on monsoon rainfall, whereas Himalayan rivers have
significant contribution from the melting of snow,” he added.

Global warming therefore has more influence on Himalayan rivers with
frequent floods and droughts than South Indian (Peninsular) rivers.
Climate change is expected to reduce the discharge of snow and ice
melt water in Himalayan large rivers (like Ganges, Brahmaputra, Indus
and Yangtze), which is very essential for food security of millions of
people in Asia.

He said it has been demonstrated by recent studies that the world will
experience changes in the river discharge with some major rivers will
have significant increases in flood flows, while other river basins
may experience drastic reduction in water flow.

“We plan to conduct a group effort to use sedimentary archives, both
onshore and offshore, to trace the evolutionary history of Asian big
river systems,” Dr Masood Ahmad said.

Bt brinjal: National Biodiversity Authority accuses seed firms of biopiracy on Indian egg plant

Syed Akbar
Hyderabad: The controversy surrounding Bt brinjal, the first
genetically modified food crop developed in India, has turned murkier
with the National Biodiversity Authority planning to launch
prosecution against a seed company for alleged bio-piracy.

The National Biodiversity Authority, which regulates matters
pertaining to biodiversity protection, conservation and use in India,
will lodge a complaint against the alleged violators of the Biological
Diversity Act for “bio-piracy in promoting Bt brinjal”. The commercial
launch of Bt brinjal has already been kept in abeyance by the Central
government following concerns over health, biological and other issues.

According to information provided to Environment Support Group (ESG)
in response to a Right to Information (RTI) query, the NBA admitted
that the “matter was under advanced stage of lodging a complaint”. The
filing of the complaint against this serious environmental crime
assumes launching of criminal prosecution against the violators.

Leo F Saldanha, coordinator/trustee of the Environment Support Group
had filed a complaint accusing, the world's largest agritech company
Monsanto along with its Indian partner Mahyco and several government
institutions, of accessing over 16 varieties of brinjal endemic to
India in comprehensive violation of the Biological Diversity Act while
promoting the commercial release of transgenic Bt brinjal.

Chronic kidney disease strikes Indians at a younger age. The mean age for chronic kidney disease or CKD in India is 50 years, though the disease can strike even at 35

Syed Akbar
Hyderabad:  Chronic kidney disease strikes Indians at a younger
age. The mean age for chronic kidney disease or CKD in India is 50
years, though the disease can strike even at 35.

Within the country, CKD strikes at a younger age among people living
in the north. CKD patients from the east are much older. Patients with
CKD of unknown cause (etiology) are younger, poorer and more likely to
present with advanced kidney troubles.

A multi-city study conducted by a team of doctors including those from
Hyderabad and Visakhapatnam revealed that 35.5 per cent of patients,
whose data was collected, are from the south while 27.9 per cent are
from the north. About 25 per cent of patients are from the west and 11
per cent from the east.

The research was based on the data collected from the Indian Chronic
Kidney Disease Registry. The study revealed that kidney complications
caused by diabetes (diabetic nephropathy) is the commonest cause (31
per cent), followed by CKD of undetermined etiology (16 per cent). The
study revealed that about 48 per cent cases are in stage V of kidney
disease. Incidentally, they are younger than those in stages III and IV.

Patients in lower income groups had more advanced CKD. The study
confirms the emergence of diabetic nephropathy as the pre-eminent
cause in India. It is the first ever research report based on the data
of Indian CKD Registry, which was set up seven years ago.

“CKD of undetermined etiology is encountered most frequent in the
southern part of the country (20.2 per cent) but in the East Zone, it
was reported in only 10 per cent. Diabetic nephropathy was reported
less frequently from the West Zone,” the study pointed out.

Chronic kidney disease has emerged as a major public health problem in
the last 10 years. However, there has been no research study on the
gravity of the health menace. The present study highlighted difference
in the CKD population going to private or public sector hospitals.

The CKD population in the public sector hospitals comprised a higher
proportion of younger patients from poorer socioeconomic classes
presenting in stages V CKD of uncertain etiology. However, there was
no difference in the proportion of diabetic kidney disease.

Rise in hypertension or high blood pressure in rural areas

Syed Akbar
Hyderabad: The life in the countryside is no longer calm and
peaceful, if medical statistics on hypertension are any indication.
About 63 per cent of people in rural areas suffer from diastolic
hypertension and two-thirds of people do not know about the bad
effects of hypertension or high blood pressure on one’s health.

There is a high (45 per cent) prevalence of cardio-metabolic risk.
Elevated cardio-metabolic risk scores were associated with
statistically significant graded
elevation in blood pressure.

A study conducted by a team of city doctors, the first one to assess
knowledge, awareness and practice about hypertension in patients on
anti-hypertensive medications in rural Andhra Pradesh, revealed that a
high prevalence of hypertension and pre-hypertension in the countryside.

Dr Mohammed A Rafey, Dr R Santosh, Dr SG Moazzam, P Sowmiya and
Abhilash S Pillai of Apollo Hospitals conducted the research. They
found that 69 per cent of patients, who are on anti-hypertensive
treatment, had uncontrolled hypertension.

“Early heart disease is a major cause for morbidity and mortality in
India. There is a high prevalence of cardiovascular risk factors like
hypertension and diabetes. Characterizing the hypertension profile and
early detection of patients with cardio-metabolic disarray in Indians
will be key in planning primary and secondary interventions to reduce
the cardiovascular disease burden in India,” said Dr Mohammad Rafey.

Only a third, 34 per cent of those found to be hypertensive were aware
they had hypertension. A majority 71.2 per cent of them were taking
antihypertensive medications.
Of those who were aware they had hypertension and were taking
anti-hypertensive medications, more than two-third (69 per cent)
patients had uncontrolled hypertension with an average blood pressure
of 139/99 mmHg.

There was no significant difference between the blood pressure levels
of those, who were illiterate, and those, who were literate.

Almost half of the individuals, who underwent screening, were found to
be at increased cardio-metabolic risk. Hypertension remains a major
risk factor for patients dying of heart disease. Indians are at risk
for death from heart disease at an earlier age compared to most other
emerging economies.

Onset of hypertension can be prevented and delayed with simple healthy
lifestyle interventions like, lowering salt intake, eating more fruits
and vegetables, avoiding high fat diet, regular exercise. In patients
with hypertension, in addition to healthy lifestyle interventions,
adequate dose and number of medications can control blood pressure in
the majority of patients and thereby prevent damage to target organs
including the heart, kidney and brain.

Bacteria are good for health, protect us from cancers, and other serious health issues

Syed Akbar
Hyderabad: “Stop killing and demonizing microbes”. This is the
new health campaign by scientists around the world, particularly those
in India.

Contrary to popular belief, several research studies including in
Hyderabad have revealed that a number of microbes particularly
bacteria actually boost the immune system in human beings and protect
them from dangerous diseases like asthma and cancer. The researchers
warn against indiscriminate use of antibiotics and cosmetics including
anti-bacterial soaps as they kill microbes that keep people healthy.

In Indian setting where hygiene is often compromised, the beneficial
result of these microbes explains the good health of a vast majority
of people living even in slums.

According to researchers at the University of Hyderabad, the human
body contains about 100 trillion bacterial cells with 3.3 million
genes. This is in contrast to just 30,000 genes decoded so far in
human genome. These bacterial genes play a great role in shaping the
behaviour of humans and the physiological and biological functioning
of the human body.

“Excessive use of cosmetics, antibiotics and anti-germ soaps does have
wide spread implication on individual’s health. Microbes protect
people from cancers and other diseases. Killing them is harmful for
human body,” says microbiologist Dr N Surya Prakash.

Microbiota co-inhabiting human beings regulate the immune system and
prevent people from allergies and immune deregulation, warn
researchers. Daily shaving, shampooing, scrubbing with antibacterial
soaps, gargle with spirited mouthwashes and then spraying denat- and
brut-based deodorants have devastating impact on the body surface
microbiota, points out a senior researcher from the University of
Hyderabad.

According to a research study, exposure to microbes during early
childhood is associated with protection from immune-mediated diseases
such as inflammatory bowel disease and asthma. Experiments in
germ-free mice showed invariant natural killer T cells accumulate in
the mucus membrane of intestines and lung, resulting in increased
morbidity of inflammatory bowel disease and allergic asthma.

Another study suggests that microbes furnish some of their benefits in
an unexpected way. Researchers have found that the typical intestinal
bacteria in mice rein in a rare type of immune cell, curtailing asthma
and colitis in the rodents.

Flame virus creates havoc: Iran blames Israel and West for the most complex, devastating computer virus ever

By Syed Akbar


Facts About Flame Virus


1. Flame virus uses keyloggers and screenshot to transmit data to the hacker.

2. It could create cyber catastrophe if it hits a large nation like India.

3. It is the king of espionage and steals all the data from computer
including the songs played, words exchanged in chat, and the pixs
stored in hard disk.

4. The virus can steal crucial nuclear, space, scientific and
government information within no time and passes it on to the hacker.

5. International Telecommunications Union issues the “most serious
warning” to all nations

6. Most complex, sophisticated and complete data spy tool, 20 times
more powerful than the existing one

7. The virus is master-controlled by 80 remotely accessed computers
maintained by the virus creators

=========
A major computer virus is now threatening the cyber
security and crucial installations of several nations. Called the
Flame Virus, it could spy everything one does on a computer, sitting
within the confines of office or home, including the film songs one
listens to, the crucial data stored on the hard disk and the chat
between friends.

The virus is also capable of stealing vital information from
governments and scientific institutions, throwing up a major cyber
security challenge. It is the most complex of all computer viruses
created so far and thus quite difficult to decode and fight back. The
virus has been hailed as the king of espionage with capabilities to
secretly record conversations.

Flame virus has affected hundreds of computers within a day of its
discovery, in the Arab world, with the prime target being Iran.
Incidentally, Iran was the target of similar attack two years ago,
when its nuclear system was hacked.

According to cyber security expert, MH Noble, the Flame virus uses
keyloggers and screenshots, which means everything done on a computer
is transmitted to the hacker.

If the virus hits India, it could result in a major cyber catastrophe.
India is fast joining exclusive clubs of nations in nuclear
technology, information and communication technology and space
technology and remote sensing. However, Flame virus is not of
immediate concern for Indian Intelligence, nuclear and scientific
bodies as the security system is foolproof.

Cyber security experts allege that Flame virus could be the handiwork of some
software security solutions company, which want to market its new
anti-virus product. The prime target seems to be developing countries,
where internet security is often
compromised. There are however, no reports of the flame virus infection so
far in India. Luckily, India has escaped similar major attacks in the past.

It is the third cyber attack weapon targeting systems in the Middle
East to be exposed in recent years. Iran has alleged that the West and

Israel are orchestrating a secret war of sabotage using yber warfare
and targeted assassinations of its
scientists as part of the dispute over its nuclear programme.
Stuxnet attacked Iran's nuclear programme in 2010, while a related
programme, Duqu, named after the Star Wars villain, stole data.

Monday, 28 May 2012

Want to prevent prostate cancer? Scientists suggest indulge in more sex to prevent prostate cancer

By Syed Akbar

Want to get rid of prostate cancer, which is fast becoming a common health
hazard in men? Just increase your sexual activity and you will be saved from
prostrate cancer to a great extent. Each increase of three ejaculations per
month across the man’s lifetime is associated with a 15 per cent decrease in
the risk of prostate cancer.
According to Dr June Machover Reinisch of The Kinsey Institute and former
professor in the departments of psychology and psychiatry at Indiana
University, USA, it is a myth that excessive sexual activity will increase
the
risk of prostate cancer. The truth is that it will decrease the risk and
keeps the
prostate gland in good function.
Dr June Machover was in Hyderabad to present her research studies on sex
and sexual practices. According to her, many physicians have believed that
men who participate in high levels of sexual activity are at increased
risk for
prostate cancer. One suggested basis for this hypothesis is the
possibility that
increased sexual activity may be an indication of higher levels of androgen
(male hormones) and therefore a higher risk of developing prostate cancer,
which has been related to male hormone levels.
However, a study conducted by a group of researchers from the National
Cancer Institute and John Hopkins and Harvard University revealed that
increased sexual activity will in fact reduce the risk of prostate cancer.
The researchers selected as many as 29,342 men, between 46 and 81 years,
and conducted a study on their sexual pattern for over eight long years. Only
men who did not have a diagnosis of prostate cancer at the beginning of the
eight years were included. So everybody was prostate cancer-free.
At the beginning of the study the men were questioned about the average
number of ejaculations per month they had, between the ages of 20 and 29,
then between 40 and 49, and then during the past year.
The study focused on the frequency of ejaculation, including sexual
intercourse, nocturnal emissions, and masturbation. Every two years after the
beginning of the study the men were asked, again, whether they had received
a diagnosis of prostate cancer.
"Of the 29,342 men who began the study without a diagnosis of prostate
cancer, by the end of eight years 1,449 cases had been diagnosed. That’s
approximately 5 per cent of the men. Remember, they are older in age, so we
expect them to start to get prostate cancer. With every decade that same
percentage get prostate cancer, so we believe that 80 per cent of 80 year
olds
have prostate cancer, and 90 per cent of 90 year olds have prostate cancer,
and 70 per cent of 70 year olds have prostate cancer," Dr June pointed out.
She said between ages 20 and 29 the men reported an average of 15
ejaculations a month. Between 40 and 49, 11 ejaculations a month was
average, and between 50 and 59 9.5 per month. Men 60 and older reported an
average of 5 ejaculations per month.
"Most categories of ejaculatory frequency were not related to the risk of
prostate cancer. However, a lower risk was found in the group of men with
the highest frequency of ejaculation. Each increase of three ejaculations per
month across the man’s lifetime was associated with a 15 per cent decrease in
the risk of prostate cancer. So the more ejaculations you had, the less
likely
you were to have prostate cancer, and every time you had three more as an
average per month, you were 15 per cent less likely to have prostate cancer,"
she said.

Hormonal cycles for men? Scientists say men too have hormonal cycles

By Syed Akbar
Men too have regular hormone cycles. And the secretion of the sex hormones in men regulate their daily routine particularly emotions, temper and anger.
Latest research by sex experts reveals that women alone are not regulated by sex hormones and hormonal cycles. Men too have such cycles though in a different way. While women have monthly cycles, men have both daily hormone cycles and yearly hormone cycles.
“It is a myth that human males do not have hormonal cycles. Now, there is much data that suggests that men have both daily hormone cycles and perhaps yearly hormone cycles. It’s generally believed that, or at least there’s an understanding, without any questioning, that men live in a kind of steady state of hormonal calm, and therefore they’re not at the mercy of fluctuating sex hormones like their female compatriots. Nothing could be further from the truth,” observes Dr June Machover Reinisch of The Kinsey Institute and former professor in the Departments of Psychology and Psychiatry at Indiana University, USA.
According to Dr June, “hormonal rhythms are sometimes, in some women, accompanied by emotional cycles and physical changes that our cultures loves to make jokes about, and have even used, unfortunately, as a rationale on occasion for limiting women’s access to power, leadership, and even some professions. Like a jet plane fighter or something like that. The assumption that goes along with this misunderstanding is that men experience no such cyclic biological mood or behavioral kinds of patterns. But this is not true. Men too have hormonal cycles”. 
She points out that the hormonal cycles in men have behavioral or mood consequences that are related to them. Daily cycles in men are called circadian cycles – circa, meaning around, and the dia part meaning day, and annual rhythms are called circannual rhythms. Research studies have revealed a daily rhythm in testosterone (male hormone) production. It’s the main androgen that’s made, and that fuels male sexual function and libido in males. Incidentally, it also is the libido or desire hormone for females.
These hormones are also critically involved in gestation; that is, in fetal development, in the development of male sexual organs and the male brain. Males and females don’t have exactly the same brain – they start out with the same brain, but when these male hormones wash over it, it changes it a little bit. And it’s also the same hormone that takes the basis for genitals.
Dr June says that although females do have some testosterone, males produce much higher levels throughout their lives and it’s primarily produced in their testicles. The daily cycle of testosterone production is quite large – that is, the cycle of it – with an overall change from high to low of approximately 43 per cent over the day.
The highest levels are produced in the morning, beginning around midnight, and they start to fall around noon. The lowest levels are found in the evening. Testosterone production appears to be related primarily to the individual man’s sleep cycle, and then secondarily to the light/dark cycle of the year. There does appear to be a yearly cycle as well. The Northern Hemisphere is somewhat different from the Southern Hemisphere – that is, Western Europe, the United States, Russia and China would be the Northern Hemisphere. It’s somewhat different in the Southern Hemisphere – Australia, Africa, and South America. It seems to be higher in summer and fall and lower in winter and early spring. And there are concomitant – that is, related – changes in sperm production and so forth, that are related to that.
According to Dr June, there are no differences in the day to day mood changes between men and women, that men are no more or less unpredictable in their moods, emotions, or behavior than are women. Put another way, when comparing men and women, studies found that both men and women were subject to similar changes in mood and behavior patterns over time.
She argues that it’s just not true that women are more changeable than men. There may be some women who are affected by their menstrual cycle, but there are also men that are affected by cyclical changes in their life.
Dr June pointes out that a large company in Japan that operates buses and taxis with a large number of drivers conducted a study. And they did this study not for any scientific purposes, but because they were concerned about very high losses that had resulting from accidents, and they couldn’t figure out what to do to lower this accident rate which was costing the company a great deal of money.
So each man who was working for the company was evaluated on a day to day basis to determine whether there were any patterns in his mood and efficiency. And they did it over a month – they used the month as the basis for it. And did it on an individual basis, because obviously they couldn’t look for when they bled every month, because men don’t do that.
“There wasn’t such an obvious thing. And after they developed this information on each individual man, they used the information they collected to make schedules for each man as to when he should be off and on, and when he should drive and not drive. And the schedule of each man was adjusted to take into account the best working times for the drivers, based upon what had been learned from these individual mood and efficiency cycles which they found in the individual men. And the result was that the accident rate dropped 33 per cent”.
She argues that it thus becomes clear that individual men have mood cycles and efficiency cycles, but they were individual – you couldn’t see them from the outside. There wasn’t a signal or sign from the outside. So men have cycles too – they are just not as obvious as women’s monthly menstrual cycles, because men don’t have obvious signs, like bleeding or swelling, or something that tells us where they are.

The future of space tourism: Are human colonies possible on Mars and Moon?

By Syed Akbar


With space tourism being dubbed as the most lucrative travel industry of
the future, space scientists, astrophysicists and astrobiologists are now
busy exploring the ways and means of colonising the moon and the earth's
neighbouring planet, Mars.


Though establishing human colonies on the moon and Mars may take at least
three to four decades, travel to the outer space has already become a
reality. The next 10 years is going to witness a major boom in space
tourism, which of course is restricted to holidaying in the outer space.
The moon and the Mars mission will, however, continue to be out of the
reach of man till the next generation. But studies are already underway
and this is soon going to be a reality.


Space experts from across the globe including the USA's National
Aeronautics and Space Administration, European Union's European Space
Agency and India's Indian National Space Research Organisation, have been
deliberating theoretically what steps they should take to ensure a
comfortable space tourism project. They are also discussing the
feasibility of establishing human colonies on the moon and Mars.
Space scientists are enthusiastic about the space tourism to outer space
but are divided over the human tour packages to natural satellites and
planets.


This is because scientists do not know the short term or long term effects
of atmosphere of the moon and Mars on human beings. Sub-orbital vehicles
and orbital cities are being planned to boost space tourism to outer space
by 2020. Space tourism, though a recent phenomenon, is fast catching up
among private individuals who could afford the journey. The  cost is
highly prohibitive, about 30 million US dollars for a week long stay in outer
space.



Astronomers are also thinking of measures to bring down the space tourism price so that more and more people could avail of the facility. Some scientists foresee a reduction in the over all fares
by at least 10 per cent in the next two decades.



Presently, only the Russian Space Agency is offering space tourism packages
for the general public. Russia takes the enthusiast space tourists to the
international space station aboard a Soyuz spacecraft. It is the thrilling
experience that has attracted at least half a dozen civilians to venture
into this new tourism package.


Since the space tourism package is limited to Russian space agency, one has
to wait for at least two years after purchasing the "ticket" to enjoy the
beauty of the earth and its atmosphere, from outside while circulating the
globe in outer space. Space tourism flights are already reserved for the
next two years.


"Tickets" are now available for 2010 journeys.To ensure that
the nascent space tourism project clicks well, "spaceports" are being
planned at various locations including the United Arab Emirates, Sweden,
Singapore and at a few cities in the USA including California, Alaska and
Florida.


So far only five individuals have availed of the space tourism facility.
They are Americans Dennis Tito, Gregory Olsen and Charles Simonyi, South
African Mark Shuttleworth and American of Iranian descent Anousheh Ansari.
The latest space tourist is Charles who returned to the earth on April 21
this year after spending a fortnight in space. Russian richie rich Vladimir
Gurzdev is the next space tourist scheduled to take the space 2008 package.
Our own Indian Santosh George Kulangara, from Kerala, will fly on board the
Virgin Galactic's space ship next year.


While private space travel firms are busy devising strategies to woo space
tourists by building the required infrastructure, NASA and ESA have
launched a research on the atmospheric effects of Mars on human health.
NASA has already developed an advanced life support programme. It uses
plants to convert carbon dioxide into oxygen in closed chambers.


"To live safely on Mars, which has 95 per cent carbon dioxide in its
atmosphere, we'll have to create a lot of technology tricks like that to
survive," explains NASA scientist Douglas Ming. Explorers visiting Mars
will have to live in habitats where the oxygen is regenerated, wear
spacesuits with oxygen masks, drive radiation-proof vehicles, and grow
food by adding nutrients to the "topsoil" that currently seems unable to
nourish plants.


But before space tourists can do all of these activities on Mars, robots
need to teach humans where and how to land, where to build, and how to
survive in the harsh martian environment.


NASA is also studying the chemical composition of the soil on Mars to find
out what chemicals might be detrimental to humans if they inhale the dust.
For example, trace metals could be toxic to lungs, and dust could also
affect electronic devices like computers and vehicles that humans will need
on Mars.


NASA administrator Michael Griffin points out that it wants to build a
space civilisation on the Mars. "We have a long-term plan to put man on
Mars by 2037, Griffin says adding that Nasa is looking beyond the moon and
Mars into the inter-planetary system.

Mystery of human migration: Why did modern human beings disperse out of Africa?


By Syed Akbar

Scientists world over believe that modern humans had dispersed from 
Africa into Eurasia about 60,000 years ago. But they are not sure what 
had forced them to leave Africa after living there for about 1,00,000 
years.
Modern man evolved about 1,60,000 years ago in the African continent 
and of this, he had spent about 1,00,000 years there. And suddenly he 
started migrating from Africa about 60,000 years ago into Asia and 
Europe.
A number of major technological, economic and social developments 
in southern Africa between 80,000 and 60,000 years ago were 
responsible for the dispersion of modern human beings to different 
parts of the world, reveals a research study by Dr Paul A Mellars of the 
University of Cambridge, UK.
Dr Mellars, who is the professor of prehistory and human evolution in 
the department of archaeology at Cambridge, was in Hyderabad to 
participate in an international workshop on "Human evolution and 
disease". In his paper, "archaeological evidence for modern human 
origins and dispersal," presented at the workshop, Dr Mellars based his 
study on a number of recently investigated sites in South Africa.
"The technological and other innovations associated with these 
developments would seem to have given the modern human 
populations the crucial adaptations that were necessary to expand from 
Africa and to colonise a range of new and alien environments, and to 
rapidly expand their range over most areas of Asia and Europe," he 
pointed out.
According to Dr Mellars, recent discoveries in India and Sri Lanka 
show some striking similarities to sties in eastern and southern Africa, 
which must be very close in time to the period when the first dispersal 
from Africa took place, between 50,000 and 60,000 years ago. It would 
seem that the further dispersal eastwards of these populations 
throughout southern and south-eastern Asia was accompanied by a 
progressive loss in the complexity of the associated technologies, 
through a succession of repeated demographic and cultural founder 
effects, leading to the comparative simplicity of the earliest Australian 
technologies.
It is known that populations that were essentially modern in both 
genetic and anatomical terms had already emerged in Africa by at least 
1,50,000 years ago but it is not clear why did it take these populations a 
further 1,00,000 years to disperse to other regions of the world? 
Another question that has been haunting scientists is what were the 
crucial evolutionary and adaptive developments that allowed these 
populations to colonise a range of entirely new and alien environments 
and to successfully compete with, and replace, the long-established, 
and presumably well adapted, archaic populations in these regions? 
It is interesting to see that two separate approaches to the analysis of 
mtDNA (mitochondrial DNA) patterns in present-day African lineage 
point strongly to an episode of rapid population growth in the ancestral 
Africa populations centered broadly within the time range from 60,000 
to 80,000 years ago, i.e., some 1,00,000 years after the inferred most 
recent common ancestor of mitochondrially modern populations in 
Africa. 
Clearly, the precise age of these inferred population expansions 
depends on the accuracy of the assumed mutation rate of mtDNA, but 
the evidence as a whole points strongly to a major and apparently rapid 
increase in African population numbers much earlier than that 
experienced in either Asia or Europe and apparently involving 
expansion by means of a demographic "diffusion wave" from a 
relatively small population nucleus (probably confined to a fairly small 
region of Africa) to other parts of the continent.  
The central question is what could have caused this apparently dramatic 
expansion in African populations between 60,000-80,000 before 
present, and it is here that recent archaeological research in southern 
and central Africa becomes central to the interpretation of the 
demographic data.
The most relevant evidence at present comes from a number of sites 
located close to the southern tip of Africa in Cape Province, most 
notably from Blombos Cave and Klasies River on the southern coast 
and those of Boomplaas Cave and Diepkloof, further to the north and 
west.
Dr Mellars points out that the excavations at these sites revealed "soft 
hammer" techniques of flaking; new forms of both specialised skin 
working tools (end-scrapers) and tools for the controlled shaping of 
bone and wooden artefacts (so-called burin forms); a range of 
extensively shaped bone tools, apparently used as both tips of throwing 
spears and sharply pointed awls for skin working; new forms of 
carefully shaped stone inserts, probably used as tips and barbs of either 
hafted throwing spears or conceivably wooden arrows; large numbers 
of perforated estuarine shells, evidently used as personal ornaments of 
some kind; and large quantities of imported red ochre, including two 
pieces from the Blombos cave with carefully incised and relatively 
complex geometrical designs on their surfaces. These designs represent 
the earliest unambiguous forms of abstract "art" so far recorded.
Equally significant in these sites is the evidence for the large-scale 
distribution or exchange of both high-quality stone for tool production 
and the recently discovered shell beads from the Blombos cave, in both 
cases either transported or traded over distances of at least 20-30 km. 
All of these features show a striking resemblance to those which 
characterise fully modern or "Upper Palaeolithic" cultures in Europe 
and western Asia, which first appeared with the initial arrival of 
anatomically and behaviourally modern populations at about 
45,000-50,000 BP (before present) i.e., some 20,000 years later than 
their appearance in the African sites.
Moreover the total population numbers in Africa decreased 
significantly at this time, owing to the onset of extremely dry 
conditions in many parts of Africa between 60,000 and 30,000 BP.
"The point is simply that increased levels of technological efficiency 
and economic productivity in one small region of Africa could have 
allowed a rapid expansion of these populations to other regions and an 
associated competitive replacement (or absorption) of the earlier, 
technologically less "advanced," populations in these regions," Dr 
Mellars argues. 
The pivotal question, of course, is what caused these radical changes in 
the technology, economy, and social patterns of African groups about 
80,000-70,000 BP, asks Dr Mellars.
He says the emergence of distinctively modern patterns of culture and 
technology was due to a sudden change in the cognitive capacities of 
the populations involved, entailing some form of neurological 
mutation.
"Or alternatively (and more prosaically), we could look for an 
interpretation in terms of some major shift in the adaptive and selective 
pressures to which the human populations were subjected, perhaps 
precipitated by some major episode of climatic and environmental 
change. In this context, the obvious candidate would be the sharp 
oscillations between wetter and drier climatic conditions that marked 
the transition from oxygen isotope stage 5 to stage 4, as reflected in the 
deep-sea core and ice-core climatic records," he says.
The final, and most controversial, issue at present is exactly when and 
how these anatomically and genetically modern populations first spread 
from Africa to other parts of Asia and Europe. Here there are two main 
possibilities. According to Dr Mellars, the first is that the initial 
expansion occurred via North Africa and the Nile valley, with 
subsequent dispersal to both the west into Europe and to the east into 
Asia. The second is that the initial dispersal was from Ethiopia, across 
the mouth of the Red Sea, and then either northward through Arabia or 
eastward along the south Asian coastline to Australasia-the so-called 
"southern" or "coastal" route.

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Mother's Care

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Minnu The Cat & Her Kittens Brownie, Goldie & Blackie

Someone with Nature

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Syed Akbar in an island in river Godavari with Papikonda hills in the background

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Convention on Biodiversity

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Syed Akbar at the 11th Conference of Parties to the United Nations Convention on Biological Diversity