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Latest Evolutionary history of life Stories

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2011-01-11 08:30:00

New findings from UC Riverside-led team alter traditional ideas about ancient ocean chemistry Geologists at the University of California, Riverside have found chemical evidence in 2.6-billion-year-old rocks that indicates that Earth's ancient oceans were oxygen-free and, surprisingly, contained abundant hydrogen sulfide in some areas. "We are the first to show that ample hydrogen sulfide in the ocean was possible this early in Earth's history," said Timothy Lyons, a professor of...

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2011-01-06 08:24:08

Persistent lack of oxygen in Earth's oceans affected animal evolution The oceans became oxygen-rich as they are today about 600 million years ago, during Earth's Late Ediacaran Period. Before that, most scientists believed until recently, the ancient oceans were relatively oxygen-poor for the preceding four billion years. Now biogeochemists at the University of California-Riverside (UCR) have found evidence that the oceans went back to being "anoxic," or oxygen-poor, around 499 million years...

2010-10-29 19:07:48

The giant dragonflies of ancient Earth with wingspans of up to 70 centimeters (28 inches) are generally attributed to higher oxygen atmospheric levels in the atmosphere in the past. New experiments in raising modern insects in various oxygen-enriched atmospheres have confirmed that dragonflies grow bigger with more oxygen, or hyperoxia. However, not all insects were larger when oxygen was higher in the past. For instance, the largest cockroaches ever are skittering around today. The question...

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2010-03-25 10:28:25

In the '80s, Spanish researchers found the first fossils of Cloudina in Spain, a small fossil of tubular appearance and one of the first animals that developed an external skeleton between 550 and 543 million years ago. Now paleontologists from the University of Extremadura have discovered a new species, Cloudina carinata, the fossil of which has preserved its tridimensional shape. "Cloudina carinata is characterized by its elaborate ornamentation and complexity of the shells and tube that...

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2009-09-10 05:25:00

Analysis of a rock type found only in the world's oldest oceans has shed new light on how large animals first got a foothold on the Earth. A scientific team led by Professor Robert Frei at the University of Copenhagen in Denmark, and including scientists from Newcastle University, UK, and universities in Uruguay and Southern Denmark, have for the first time managed to plot the rise and fall of oxygen levels in the Earth's atmosphere over the last 3.8 billion years. By analyzing the isotopes...

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2009-07-07 06:45:00

Nearly everyone can recall the high school textbook illustrations of the planet's first land-dwelling creatures, ubiquitously represented as comic-looking fish with short, stumpy legs.  A team of paleontologists, however, are challenging these standard depictions, saying that the earth's first tetrapods were for more diverse than previously suspected. "Some looked like crocodiles, some looked like little lizards, some like moray eels, and some were snake-like," explained Jennifer Clack...

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2008-03-26 15:25:00

UC Riverside-led study tracked biogeochemical signatures preserved in ancient sedimentary rocks to establish nature and timing of oxygenation of Earth's atmosphereA deficiency of oxygen and the heavy metal molybdenum in the ancient deep ocean may have delayed the evolution of animal life on Earth by nearly two billion years, a study led by UC Riverside biogeochemists has found. The researchers arrived at their result by tracking molybdenum in black shales, which are a kind of sedimentary rock...

11a42b0d4b4dd33a1b1cf62892062f911
2008-01-08 15:55:00

BLACKSBURG, Va. -- Scientists have known for some time that most major groups of complex animals appeared in the fossils record during the Cambrian Explosion, a seemingly rapid evolutionary event that occurred 542 million years ago. Now Virginia Tech paleontologists, using rigorous analytical methods, have identified another explosive evolutionary event that occurred about 33 million years earlier among macroscopic life forms unrelated to the Cambrian animals. They dubbed this earlier event...

58c0db02ce27a4bec66beb3442feaa61
2006-12-08 13:00:00

The sudden appearance of large animal fossils more than 500 million years ago "“ a problem that perplexed even Charles Darwin and is commonly known as "Darwin's Dilemma" "“ may be due to a huge increase of oxygen in the world's oceans, says Queen's paleontologist Guy Narbonne, an expert in the early evolution of animals and their ecosystems. In 2002, Dr. Narbonne and his research team found the world's oldest complex life forms between layers of sandstone on the southeastern...


Latest Evolutionary history of life Reference Libraries

Paleontology
2014-01-12 00:00:00

Paleontology or Palaeontology is the scientific study of prehistoric life, including the study of fossils to determine the organisms evolution and interactions with each other and their environments. Paleontological observations have been documented as far back as 5th century BC. The science became established in the 18th century as a result of Georges Cuvier’s work on comparative anatomy, and it developed quickly within the 19th century. The term itself comes from Greek palaios, meaning...

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Word of the Day
barratry
  • The offense of persistently instigating lawsuits, typically groundless ones.
  • An unlawful breach of duty on the part of a ship's master or crew resulting in injury to the ship's owner.
  • Sale or purchase of positions in church or state.
This word ultimately comes from the Old French word 'barater,' to cheat.
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