2010 August 5. National Science Foundation Press Release 10-136: The
Secret Life May Be As Simple As What Happens Between the Sheets--Mica
Sheets. Excerpt: …The so-called "life
between the sheets" mica hypothesis was developed by Helen Hansma of the
University of California, Santa Barbara, with funding from the National
Science Foundation (NSF). …According to the hypothesis, structured
compartments that commonly form between layers of mica--a common mineral
that cleaves into smooth sheets--may have sheltered molecules that were
the progenitors to cells. Provided with the right physical and chemical
environment in the structured compartments to survive and evolve, the
molecules eventually reorganized into cells, while still sheltered
between mica sheets.
…Because mica surfaces are hospitable to living cells
and to all the major classes of large biological molecules, including
proteins, nucleic acids, carbohydrates and fats, the "between the
sheets" mica hypothesis is consistent with other well-known hypotheses
that propose that life originated as RNA, fatty vesicles or primitive
…Some micas are estimated to be over 4 billion years
old. And micas such as biotite have been found in regions containing
evidence of the earliest life-forms, which are believed to have existed
about 3.8 million years ago.
… Hansma says that recent advancements in imaging
techniques, including the AFM [atomic force microscopy], made possible
her recent research...
2010 May 19. Calcium from new supernova 'could unlock secrets to
life on Earth'. By Andrew Hough. Telegraph.co.uk. Excerpt: …Astronomers believe they have found a
cosmic link to how calcium is formed in people's bones.
…They say a new type of supernova, called SN2005E, may
be the chief source of calcium in the universe and on Earth.
…Scientists say the mineral provides vital strength to
bones, which could show how humans have an ability to stand upright, the
Nature journal …reported.
…So much calcium was present that it accounted for half
the material thrown out by the explosion.
2010 May 17. A
Marine Chemist Studies How Life Began. By Claudia Dreifus. The NY
DO WE KNOW HOW THEY BECAME LIFE?
A. We are closing in on that
question. The Earth had to cool down enough for water to appear. Water
allows molecules to dissolve and interact, which is why it is essential
to life. We do know that we went from simple molecules to more complex
molecules and eventually to RNA, which evolved into DNA. This took about
a billion years.
...Q. SO WE’RE PROBABLY NOT ALONE?
A. I don’t want to say “we” because
people immediately think of something like a human being. But life as we
know it — a self-replicating system — is probably not unique to the
Earth. Under the right conditions, with the right chemistry, it can
happen. There may be simple chemistry happening on Titan, a moon of
Saturn. Some people think it could be happening on the satellites of
Jupiter. There are compelling reasons to think that Mars was wet when it
was young and that the raw materials for life could have been there. We
don’t know how far it progressed.
2009 August 19. NASA
NASA Research Reveals Major Insight Into Evolution
Of Life On Earth. Excerpt:
MOFFETT FIELD, Calif.
-- Humans might not be walking on Earth today
if not for the ancient fusing of two microscopic,
single-celled organisms called prokaryotes,
NASA-funded research has found.
By comparing proteins present in more than 3000
different prokaryotes - a type of single-celled
organism without a nucleus - molecular biologist
James A. Lake from the University of California
at Los Angeles' Center for Astrobiology showed
that two major classes of relatively simple
microbes fused together more than 2.5 billion
years ago. Lake's research reveals a new pathway
for the evolution of life on Earth....
This endosymbiosis, or merging of two cells,
enabled the evolution of a highly stable and
successful organism with the capacity to use
energy from sunlight via photosynthesis. Further
evolution led to photosynthetic organisms producing
oxygen as a byproduct. The resulting oxygenation
of Earth's atmosphere profoundly affected the
evolution of life, leading to more complex organisms
that consumed oxygen, which were the ancestors
of modern oxygen-breathing creatures including
"Higher life would not have happened without
this event," Lake said. "These are
very important organisms. At the time these
two early prokaryotes were evolving, there was
no oxygen in the Earth's atmosphere. Humans
could not live. No oxygen-breathing organisms
2009 June 15. New
Glimpses of Life’s Puzzling Origins. By Nicholas
Wade, The NY Times. Excerpt:
Some 3.9 billion years ago, a shift in the orbit
of the Sun’s
outer planets sent a surge of large comets and
asteroids careening into the inner solar system....
Yet rocks that formed on Earth 3.8 billion years
ago, almost as soon as the bombardment had stopped,
contain possible evidence of biological processes.
If life can arise from inorganic matter so quickly
and easily, why is it not abundant in the solar
system and beyond? If biology is an inherent
property of matter, why have chemists so far
been unable to reconstruct life, or anything
close to it, in the laboratory?
The origins of life on Earth bristle with puzzle
and paradox. Which came first, the proteins
of living cells or the genetic information that
makes them? How could the metabolism of living
things get started without an enclosing membrane
to keep all the necessary chemicals together?
But if life started inside a cell membrane,
how did the necessary nutrients get in?
The questions may seem moot, since life did
start somehow. But for the small group of researchers
who insist on learning exactly how it started,
frustration has abounded. Many once-promising
leads have led only to years of wasted effort....
In the last few years, however, four surprising
advances have renewed confidence that a terrestrial
explanation for life’s origins will eventually
2009 May 20. NASA
STUDY SHOWS ASTEROIDS MAY HAVE ACCELERATED
LIFE ON EARTH.
NASA RELEASE: 09-11. Excerpt:
WASHINGTON -- A NASA-funded study indicates
that an intense asteroid bombardment nearly
4 billion years ago may not have sterilized
the early Earth as completely as previously
thought. The asteroids, some the size of Kansas,
possibly even provided a boost for early life.
The study focused on a particularly cataclysmic
occurrence known as the Late Heavy Bombardment,
or LHB. This event occurred approximately 3.9
billion years ago and lasted 20 to 200 million
years. ... while the Late Heavy Bombardment
might have generated enough heat to sterilize
Earth's surface, microbial life in subsurface
and underwater environments almost certainly
would have survived. "Exactly
when life originated on Earth is a hotly debated
topic," said Michael H. New, the astrobiology
discipline scientist and manager of the Exobiology
and Evolutionary Biology Program at NASA Headquarters
in Washington. "These findings are significant
because they indicate that if life had begun
before the LHB or some time prior to 4 billion
years ago, it could have survived in limited
refuges and then expanded to fill our world."
"Our new results point to the possibility
life could have emerged about the same time
that evidence for our planet's oceans first
appears," said Mojzsis, principal investigator
of the project.
A growing scientific consensus is that during
our solar system's formation, planetary bodies
were pummeled by debris throughout the Late
Heavy Bombardment. ...Surface habitats for microbial
life on early Earth would have been destroyed
repeatedly by the bombardment. However, at the
same time, impacts could have created subsurface
habitats for life, such as extensive networks
of cracks or even hydrothermal vents. Any existing
microbial life on Earth could have found refuge
in these habitats.
2008 December 8. Meteor
impacts may have sparked life on Earth. By Emma Young, New
Scientist. Excerpt: While space rocks hurtling
in from space threaten to deal modern life a mortal blow, meteorite
impacts during Earth's early history may have played a pivotal role in
kick-starting life on the planet.
Exactly how and when organic molecules appeared in
abundance on the young Earth, leading to the origin of life about 4
billion years ago, has been unclear. But new research suggests that
meteor impacts could have created amino acids, the building blocks of
Yoshihiro Furukawa at Tohoku University in Sendai,
Japan, and colleagues used a high-velocity propellant gun to simulate
the impacts of ordinary carbon-containing chondrite meteorites - the
most common type of meteorite - into the early ocean. Afterwards, they
recovered a variety of organic molecules, including fatty acids, amines,
and an amino acid.
Oceans began to form about 4.3 billion years ago, when
meteorites were hitting Earth about 1000 times more frequently than they
do today, says Furukawa. "This study is the first to show that an amino
acid can be synthesised by a naturally possible mechanism on the early
Earth," he says....
2008 October 16. Volcanoes
May Have Provided Sparks and Chemistry for First Life. NASA Earth
Observatory. Excerpt: Lightning and gases
from volcanic eruptions could have given rise to the first life on
Earth, according to a new analysis of samples from a classic
origin-of-life experiment by NASA and university researchers....
...From 1953 to 1954, Professor Stanley Miller, then at
the University of Chicago, performed a series of experiments with a
system of closed flasks containing water and a gas of simple molecules.
At the time, the molecules used in the experiment (hydrogen, methane,
and ammonia) were thought to be common in Earth's ancient atmosphere.
The gas was zapped with an electric spark. After
running the experiment for a few weeks, the water turned brown. When
Miller analyzed the water, he found it contained amino acids, which are
the building blocks of proteins -- life's toolkit... The spark provided
the energy for the molecules to recombine into amino acids, which rained
out into the water....
...Professor Jeffrey Bada, a co-author of the paper,
was [Miller's] graduate student in chemistry between 1965 and 1968....
"...When Adam and I found the samples from the original experiments,
it was a great opportunity to reanalyze these historic samples using
modern methods," said Bada. The team wanted to see if modern equipment
could discover chemicals that could not be detected with the techniques
of the 1950s. They analyzed the samples and turned to Daniel Glavin and
Jason Dworkin of NASA's Goddard Space Flight Center in Greenbelt, Md....
..."We discovered 22 amino acids, 10 of which have
never been found in any other experiment like this," said Glavin. This
is significant because thinking on the composition of Earth's early
atmosphere has changed. Instead of being heavily laden with hydrogen,
methane, and ammonia, many scientists now believe Earth's ancient
atmosphere was mostly carbon dioxide, carbon monoxide, and nitrogen....
2006 June 6. STUDY
SHOWS OUR ANCESTORS SURVIVED 'SNOWBALL EARTH' -
Earth Observatory. Excerpt:
It has been 2.3 billion years since Earth's
atmosphere became infused with enough oxygen
to support life as we know it. About the same
time, the planet became encased in ice that
some scientists speculate was more than a
half-mile deep. That raises questions about
whether complex life could have existed before "Snowball
Earth" and survived, or if it first evolved
when the snowball began to melt. New research
shows organisms called eukaryotes -- organisms
of one or more complex cells that engage in
sexual reproduction and are ancestors of the
animal and plant species present today --
existed 50 million to 100 million years before
that ice age and somehow did survive. The
work also shows that the cyanobacteria, or
blue-green bacteria, that put the oxygen in
the atmosphere in the first place, apparently
were pumping out oxygen for millions of years
before that, and also survived Earth's glaciation.
The findings call into question the direst
models of just how deep the deep freeze was,
said University of Washington astrobiologist
Roger Buick, a professor of Earth and space
sciences. While the ice likely was widespread,
it probably was not consistently as thick
as a half-mile, he said. "That kind of
ice coverage chokes off photosynthesis, so
there's no food for anything, particularly
eukaryotes. They just couldn't survive," he
said. "But this research shows they did
8 January 2004. NASA RELEASE
: 04-016, Borax
Minerals May Have Been Key To Start Of Life
On Earth. Astrobiologists,
supported by NASA, have announced a major
advance in understanding how life may have
originated on Earth billions of years ago.
A team of scientists report in the January
9 issue of Science that ribose and other simple
sugars that are among life's building blocks
could have accumulated in the early Earth's
oceans if simple minerals, such as borax,
DATA TO PREDICT PLANKTON BLOOMS BY ANALYZING
OCEAN COLOR -- Scientists
analyzing satellite data on ocean color
are gaining new insights into ocean productivity
and climate. A green ocean is a productive
ocean; the light from the sun fuels the "bloom" of
phytoplankton, tiny ocean plants that
turn the sea's surface a light green each
spring. This production in turn drives
ocean food webs. New research, published
in the journal Science on April 26, assesses
the color of the ocean and finds that
it may yield clues about the relation
between marine ecosystems and the climate
system. The research was funded by the
National Science Foundation (NSF) and
of Past Articles for Chapter 4