Minute fossil sea creatures recovered from sediments containing ancient DNA. Image: Lejzerowicz et al./Biology Letters
In the middle of the South Atlantic, there’s a patch of sea almost devoid of life. There are no birds, few fish, not even much plankton. But researchers report that they’ve found buried treasure under the empty waters: ancient DNA hidden in the muck of the sea floor, which lies 5000 meters below the waves.
The DNA, from tiny, one-celled sea creatures that lived up to 32,500 years ago, is the first to be recovered from the abyssal plains, the deep-sea bottoms that cover huge stretches of Earth. In a separate finding published this week, another research team reports teasing out plankton DNA that’s up to 11,400 years old from the floor of the much shallower Black Sea. The researchers say that the ability to retrieve such old DNA from such large stretches of the planet’s surface could help reveal everything from ancient climate to the evolutionary ecology of the seas. Read more
A supervolcanic eruption thought to have nearly driven humanity extinct may not have endangered the species after all, a new investigation suggests.
Supervolcanoes are capable of eruptions dwarfing anything ever seen in recorded history, expelling thousands of times more magma and ash than even a Mount St. Helens or Pinatubo. A supervolcanic eruption could wreak as much havoc as the impact of a mile-wide asteroid,by blotting out the sun with ash, reflecting its rays and cooling the Earth — a phenomenon called a “volcanic winter.” A dozen or so supervolcanoes exist today, some of them lying at the bottom of the sea. Read more
Geologists believe Yellowstone sits over a hotspot, a plume of superheated rock rising from Earth’s mantle
Yellowstone’s underground volcanic plumbing is bigger and better connected than scientists thought, geologists reported this week at the Seismological Society of America’s annual meeting.
“We are getting a much better understanding of the volcanic system of Yellowstone,” said Jamie Farrell, a c graduate student at the University of Utah. “The magma reservoir is at least 50 percent larger than previously imaged.” Read more
Remnants of Cyclopean walls built by the Mycenaeans can be found at the Acropolis in Athens, Greece. ISTOCKPHOTO
The grand Mycenaens, the first Greeks, inspired the legends of the Trojan Wars, “The Iliad” and “The Odyssey.” Their culture abruptly declined around 1200 B.C., marking the start of a Dark Ages in Greece.
The disappearance of the Mycenaens is a Mediterranean mystery. Leading explanations include warfare with invaders or uprising by lower classes. Some scientists also think one of the country’s frequent earthquakes could have contributed to the culture’s collapse. At the ruins of Tiryns, a fortified palace, geologists hope to find evidence to confirm whether an earthquake was a likely culprit. Read more
The beaches of Mauritius contain fragments of a type of rock typical of ancient continental crust — rock which could have been brought to the surface by volcanic eruptions. JACK ABUIN/ZUMA PRESS/CORBIS
A a group of international scientists have found evidence that an ancient, lost continent may be buried beneath the Indian Ocean floor.
A scientist from the University of Utah has confirmed that two continent-sized “thermochemical piles” are slowly converging at the bottom of Earth’s mantle about 1,800 miles (2,900 km) beneath the Pacific Ocean. This process, says geologist Michael Thorne, could eventually lead to a cataclysmic eruption that could “cause very massive destruction on Earth.” But don’t panic quite yet. His research suggests that this super-volcano-in-the-making may not erupt for another 100 to 200 million years. Read More