Home' Trinidad and Tobago Guardian : February 4th 2017 Contents A24 body & soul
guardian.co.tt Saturday, February 4, 2017
Ancient DNA reveals genetic
'continuity' between Stone Age,
modern populations in East Asia
In contrast to Western Europeans, new re-
search finds contemporary East Asians are
genetically much closer to the ancient hunt-
er-gatherers that lived in the same region eight
thousand years previously.
Researchers working on ancient DNA extracted from
human remains interred almost 8,000 years ago in
a cave in the Russian Far East have found that the
genetic makeup of certain modern East Asian popu-
lations closely resemble that of their hunter-gatherer
ancestors. The study, published in the journal Science
Advances, is the first to obtain nuclear genome data
from ancient mainland East Asia and compare the
results to modern populations.
The findings indicate that there was no major mi-
gratory interruption, or "population turnover," for
well over seven millennia. Consequently, some con-
temporary ethnic groups share a remarkable genetic
similarity to Stone Age hunters that once roamed the
same region. The high "genetic continuity" in East
Asia is in stark contrast to most of Western Europe,
where sustained migrations of early farmers from the
Levant overwhelmed hunter-gatherer populations.
This was followed by a wave of horse riders from Cen-
tral Asia during the Bronze Age. These events were
likely driven by the success of emerging technologies
such as agriculture and metallurgy.
The new research shows that, at least for part of East
Asia, the story differs---with little genetic disruption in
populations since the early Neolithic period. Despite
being separated by a vast expanse of history, this has
allowed an exceptional genetic proximity between
the Ulchi people of the Amur Basin, near where Rus-
sia borders China and North Korea, and the ancient
hunter-gatherers laid to rest in a cave close to the
Ulchi's native land.
The researchers suggest that the sheer scale of
Call for rethink
on working week
People shouldn't be working any more than
39 hours a week if they want to protect their
wellbeing, a new study has found.
Researchers from Australian National University
used data from 8,000 working adults as part of
the Household, Income and Labour Dynamics in
Australia Survey. They found the work limit for a
healthy life should be set at 39 hours a week, rather
than the 48-hour week limit set internationally
about 80 years ago.
Working beyond 39 hours, the researchers said,
also puts employees at risk of developing men-
tal health problems. Study co-author Professor
Lyndall Strazdins, from the Research School of
Population Health at the university, said almost
a quarter of Australians worked longer than the
recommended 39 hours.
The study also found when men and women
were considered separately, the healthy work lim-
it was 34 hours per week for women once other
commitments were considered. The healthy work
limit for men was significantly higher --- up to 47
hours a week. The researchers said this was because
generally, men spent much less time on care or
domestic work than women. Professor Strazdins
said Australians needed to dispel the widespread
belief that people had to work long hours in order
to do a good job.
"My message is to their managers and our policy
makers to start a national debate on how long is
too long," she said. She said employers must look
for ways to support people to work shorter hours.
"And [they shouldn't] expect that they have to work
longer hours to hold down that job," she said.
The study was published in the journal Social
Science and Medicine. (http://www.abc.net.au)
Exterior of Devil's Gate, the cave where the human remains were found, from
which the ancient DNA used in the study was extracted.
East Asia and dramatic variations in its climate may
have prevented the sweeping influence of Neolithic
agriculture and the accompanying migrations that
replaced hunter-gatherers across much of Europe.
They note that the Ulchi retained their hunter-fish-
er-gatherer lifestyle until recent times. (https://www.
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