(Press-News.org) Spindle-shaped inclusions in 3 billion-year-old rocks are microfossils of plankton that probably inhabited the oceans around the globe during that time, according to an international team of researchers.
"It is surprising to have large, potentially complex fossils that far back," said Christopher H. House, professor of geosciences, Penn State, and lead author.
However, the researchers not only showed that these inclusions in the rocks were biological in origin, but also that they were likely planktonic autotrophs -- free-floating, tiny ocean organisms that produce energy from their environment.
The researchers looked at marine sediment rocks from the Farrel Quartzite in Western Australia. Isotopic analysis using secondary ion mass spectrometry was carried out at UCLA. "Ken (Kenichiro Sugitani, professor, Graduate School of Environmental Studies, Nagoya University, Japan, and a co-author) discovered these unusually shaped microfossils embedded in really old rock," said House.
To determine if these inclusions were actually biological in origin, the researchers looked at 15 different samples of Farrel Quartzite and determined their stable carbon isotope ratios. The percentage of carbon 13 in the microfossils was indicative of material produced by biological processes. They found that the carbon 13 percentage in the background organic matter in the surrounding rock was different from that of the microstructures.
"When considered along with published morphological and chemical studies, these results indicate that the Farrel Quartzite microstructures are bona fide microfossils, and support the interpretation that the spindles were planktonic," the researchers report in the current issue of Geology. The morphological and chemical studies were done by Sugitani and Dorothy Oehler, who is also a co-author and research scientist, Astromaterials Research and Exploration Science Directorate, NASA -- Johnson Space Center.
The spindle-shaped microfossils are from 20 to 60 microns in length, about the size of fine sand and within the size range of today's microplankton.
Stable carbon isotope analysis can determine the biological origin of these microfossils because they used carbon dioxide to create energy and incorporated the carbon into themselves. During this process, the organisms selectively incorporate more carbon 12 than carbon 13 from the available carbon, producing a signature of biological origin.
Oehler notes that the spindles appear to be the same as those found in rocks from the Strelly Pool Formation in Western Australia and the Onverwacht Group in South Africa and Swaziland that are both 3.4 billion years old.
"The existence of these microfossils in diverse locations as far back as 3.4 billion years ago suggests that the oceans probably had life in them for a very extended period of time," said Oehler. "Moreover, this has implications beyond what we have done here, suggesting the evolution of diverse life proceeded quickly."
Also working on this project was Koichi Mimura, Graduate School of Environmental Studies, Nagoya University, Japan.
INFORMATION:
The NASA Astrobiology Institute, the Astromaterials Research and Exploration Science Directorate, Johnson Space Center and the Japan Society for the Promotion of Science supported this research.
3 billion-year-old microfossils include plankton
2013-06-07
ELSE PRESS RELEASES FROM THIS DATE:
Facebook: A confidence boost for first-gen college students
2013-06-07
ANN ARBOR—Facebook connections can help first-generation college applicants believe in their abilities to both apply to school and excel once they've enrolled, according to a new study from the University of Michigan and Michigan State University.
"We are very excited by these findings, because they suggest that the kinds of interactions supported by Facebook and other social media can play a role in helping young people, especially those who are traditionally less likely to go to college, feel more confident about their ability to get into college and to succeed there," ...
Researchers discover how brain circuits can become miswired during development
2013-06-07
NEW YORK (June 6, 2013) -- Researchers at Weill Cornell Medical College have uncovered a mechanism that guides the exquisite wiring of neural circuits in a developing brain -- gaining unprecedented insight into the faulty circuits that may lead to brain disorders ranging from autism to mental retardation.
In the journal Cell, the researchers describe, for the first time, that faulty wiring occurs when RNA molecules embedded in a growing axon are not degraded after they give instructions that help steer the nerve cell. So, for example, the signal that tells the axon to ...
Pollution in Northern Hemisphere helped cause 1980s African drought
2013-06-07
Decades of drought in central Africa reached their worst point in the 1980s, causing Lake Chad, a shallow lake used to water crops in neighboring countries, to almost dry out completely.
The shrinking lake and prolonged drought was initially blamed on overgrazing and bad agricultural practices. More recently, Lake Chad became an example of global warming.
New University of Washington research, to be published in Geophysical Research Letters, shows that the drought were caused at least in part by Northern Hemisphere air pollution.
Aerosols emanating from coal-burning ...
U of M researchers find novel gene correction model for epidermolysis bullosa
2013-06-07
(MINNEAPOLIS/ST. PAUL) June 6, 2013 – A research team led by pediatric blood and marrow transplantation experts Mark Osborn, Ph.D. and Jakub Tolar, M.D., Ph.D. from the Masonic Cancer Center, University of Minnesota, have discovered a remarkable new way to repair genetic defects in the skin cells of patients with the skin disease epidermolysis bullosa.
The findings, published today in the journal Molecular Therapy and highlighted in the most recent issue of Nature, represent the first time researchers been able to correct a disease-causing gene in its natural location ...
Earthquake acoustics can indicate if a massive tsunami is imminent, Stanford researchers find
2013-06-07
On March 11, 2011, a magnitude 9.0 undersea earthquake occurred 43 miles off the shore of Japan. The earthquake generated an unexpectedly massive tsunami that washed over eastern Japan roughly 30 minutes later, killing more than 15,800 people and injuring more than 6,100. More than 2,600 people are still unaccounted for.
Now, computer simulations by Stanford scientists reveal that sound waves in the ocean produced by the earthquake probably reached land tens of minutes before the tsunami. If correctly interpreted, they could have offered a warning that a large tsunami ...
Astronomers gear up to discover Earth-like planets
2013-06-07
If one looks only for the shiniest pennies in the fountain, chances are one misses most of the coins because they shimmer less brightly. This, in a nutshell, is the conundrum astronomers face when searching for Earth-like planets outside our solar system.
Astronomers at the University of Arizona are part of an international team of exoplanets hunters developing new technology that would dramatically improve the odds of discovering planets with conditions suitable for life – such as having liquid water on the surface.
The team presented its results at a scientific conference ...
NASA satellite reveals Tropical Storm Andrea's towering thunderstorms
2013-06-07
VIDEO:
This 3-D view from the west was derived from TRMM Precipitation Radar (PR) data captured when Andrea was examined by the TRMM satellite with the June 5, 2234 UTC (6:34...
Click here for more information.
Towering thunderstorms are a sign of a strong tropical cyclone, and NASA's TRMM satellite spotted thunderstorms reaching heights of almost 9 miles high within Tropical Storm Andrea. NASA's Aqua satellite provided an infrared view that revealed very cold cloud top ...
Math technique de-clutters cancer-cell data, revealing tumor evolution, treatment leads
2013-06-07
Cold Spring Harbor, NY -- In our daily lives, clutter is something that gets in our way, something that makes it harder for us to accomplish things. For doctors and scientists trying to parse mountains of raw biological data, clutter is more than a nuisance; it can stand in the way of figuring out how best to treat someone who is very sick.
Using increasingly cheap and rapid methods to read the billions of "letters" that comprise human genomes – including the genomes of individual cells sampled from cancerous tumors -- scientists are generating far more data than they ...
Smithsonian scientists confirm theory regarding the origins of the sucking disc of remoras
2013-06-07
Remora fish, with a sucking disc on top of their heads, have been the stuff of legend. They often attach themselves to the hulls of boats and in ancient times were thought to purposely slow the boat down. While that is a misunderstanding, something else not well understood was the origins of the fish's odd sucking disc. Scientists at the Smithsonian Institution and London's Natural History Museum, however, have solved that mystery proving that the disc is actually a greatly modified dorsal fin. The research is published in the Journal of Morphology.
The world's eight ...
Researchers discover normal molecular pathway affected in poor-prognosis childhood leukemia
2013-06-07
(Lebanon, NH, 6/5/13) — Through genetic engineering of laboratory models, researchers at Dartmouth-Hitchcock Norris Cotton Cancer Center have uncovered a vulnerability in the way cancer cells diverge from normal regenerating cells that may help treat children with leukemia as reported in the journal PNAS on June 3, 2013. Dartmouth researchers are trying to understand the key pathways that distinguish how a normal blood cell grows and divides compared to the altered growth that occurs in leukemia. In addition to the treatment of leukemia, the work has relevance for expanding ...