Latest Proterozoic Stories

Scientists find signs of 'snowball Earth' amidst early animal evolutionGeologists have found evidence that sea ice extended to the equator 716.5 million years ago, bringing new precision to a "snowball Earth" event long suspected to have taken place around that time.Led by scientists at Harvard University, the team reports on its work this week in the journal Science. The new findings -- based on an analysis of ancient tropical rocks that are now found in remote northwestern Canada...

Stratified marine basin sheds new light on early animal evolution, UC Riverside scientists sayA research team led by biogeochemists at the University of California, Riverside has developed a detailed and dynamic three-dimensional model of Earth's early ocean chemistry that can significantly advance our understanding of how early animal life evolved on the planet.Working on rock samples from the Doushantuo Formation of South China, one of the oldest fossil beds and long viewed by...

Princeton University scientists have shown that, in ancient times, the Earth's magnetic field was structured like the two-pole model of today, suggesting that the methods geoscientists use to reconstruct the geography of early land masses on the globe are accurate. The findings may lead to a better understanding of historical continental movement, which relates to changes in climate.By taking a closer look at the 1.1 billion-year-old volcanic rocks on the north shore of Lake Superior, the...

The Earth has experienced many turning points over its 4.5-billion-year history, such as periods of extreme temperature changes, asteroids and the arrival and disappearance of various life forms.  But one of the most monumental events was the Cambrian-era explosion of life some 540 million years ago, when complex, multi-cellular life burst out all over the planet.Scientists point to this critical period as leading to life as we know it today, although its precise causes were not completely...

U.S. scientists are challenging the prevailing views of the effects of the so-called Snowball Earth glaciations on life on Earth. Researchers from the University of California-Santa Barbara analyzed microfossils found in rocks at the bottom of the Grand Canyon to challenge current theories concerning the effects of the glaciers occurring approximately 635 million to 726 million years ago. Those glaciations are thought to have been responsible for the widespread deaths of early life on...

New fossil findings discovered by scientists at UC Santa Barbara challenge prevailing views about the effects of "Snowball Earth" glaciations on life, according to an article in the June issue of the journal Nature Geoscience.By analyzing microfossils in rocks from the bottom of the Grand Canyon, the authors have challenged the view that has been generally assumed to be correct for the widespread die-off of early life on Earth."Snowball Earth" is the popular term for...

An international team of geologists may have uncovered the answer to an age-old question - an ice-age-old question, that is. It appears that Earth's earliest ice age may have been due to the rise of oxygen in Earth's atmosphere, which consumed atmospheric greenhouse gases and chilled the earth.Alan J. Kaufman, professor of geology at the University of Maryland, Maryland geology colleague James Farquhar, and scientists from Germany, South Africa, Canada, and the U.S.A., uncovered evidence that...

U.S. scientists say they have found fossil evidence of animals living on Earth more than 635 million years ago, the oldest such finds. Researchers from the University of California-Riverside, the Massachusetts Institute of Technology and other institutions used compounds preserved in sedimentary rocks to confirm the existence of demosponges. Demosponges appeared during the Neoproterozoic era, 1,000 to 542 million years ago, an era of climatic extremes and biological evolutionary developments...

Scientists announced on Wednesday the discovery of the earliest evidence of animal life to date.Chemical traces found in 635-million-year-old rocks in Oman provide key evidence to support Darwin's theory that simple organisms existed before the evolution of more complex creatures, researchers said in the Feb. 5 issue of the journal Nature."Basically we have found a thread of that evidence that he predicted should be there," Roger Summons, a geobiologist at the Massachusetts...

The fossilized trail of an aquatic creature suggests that animals walked using legs at least 30 million years earlier than had been thought.The tracks -- two parallel rows of small dots, each about 2 millimeters in diameter -- date back some 570 million years, to the Ediacaran period.The Ediacaran preceded the Cambrian period, the time when most major groups of animals first evolved.Scientists once thought that it was primarily microbes and simple multicellular animals that existed prior to...