Toxic Algae 'Wiped Out Dinosaurs'

From The Telegraph:

Toxic algae rather than a massive asteroid may have wiped out the dinosaurs, scientists have claimed.

Previous studies had claimed an asteroid impact produced devastating climate changes and rising sea levels which caused the mass extinctions over the earth's 4.5 billion year existence.

But a team of American geologists and toxicologists claim algae commonly found naturally around the world could be the culprit that led to the demise of the dinosaurs.

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New Dinosaur Extinction Theory Causes Debate

An artist rendering of a space rock streaking toward Earth. Most experts think an impact off the Yucatan Peninsula 65 million years ago was the primary cause of the dinosaur demise. Others think volcanism and climate change may have played a role. A new and controversial idea suggests there was another, larger impact in India that was responsible. Stockxpert

From MSNBC:

The extinction of the dinosaurs has often been traced to a giant space rock impact on the Earth 65 million years ago. But now a scientist is saying experts have blamed the wrong impact. The new thinking was met with sharp criticism from other researchers, however.

Paleontologist Sankar Chatterjee of Texas Tech University says a giant basin in India called Shiva could also be an impact crater from the time of the dinosaurs' demise, and the crash that created it may have been the cause of the mass extinction scientists call the KT (Cretaceous–Tertiary) event, which killed off more than half the Earth's species along with the dinos. This argument runs counter to the widely-held wisdom that the Chicxulub impact on the Yucatan Peninsula off Mexico was behind the cataclysm.

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When Is A Species Endangered? Revising The Numbers

An endangered Sumatran tiger wades through a stream
Tom Brakefield / Getty

From Time Magazine:

The planet is in the middle of an extinction crisis, the sixth great wave in its history. But unlike major extinction events of the past — like the Permian-Triassic event 250 million years ago, in which 70% of all terrestrial species were wiped out, probably because of an asteroid impact or a similar natural disaster — this time human beings are the cause. Hard numbers are difficult to find, but many scientists believe Earth's species are going extinct at a rate that is up to 1,000 times higher than before human beings came on the scene.

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Suppose 21st Century Disasters Like 19th Century

Redoubt Volcano from the east, with a massive eruption plume produced by pyroclastic flows on April 21, 1990(photo by R. Clucas)

From Future Pundit:

We remember the 20th century because we've all lived in some part of it (unless of course a 9 year older is reading this) and seen lots of video about it. The century was well covered by modern media. We know less of the 19th century and some of its major natural events are not widely known.

As compared to the 19th century the 20th century was pretty calm from the standpoint of big natural changes. What I'm going to do with this post: Imagine that the 21st century turns out to be like the 19th century in terms of the severity of climate, volcanic, and other natural events.

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Giant Impact Near India -- Not Mexico -- May Have Doomed Dinosaurs

Three-dimensional reconstruction of the submerged Shiva crater (~500 km diameter) at the Mumbai Offshore Basin, western shelf of India from different cross-sectional and geophysical data. The overlying 4.3-mile-tick Cenozoic strata and water column were removed to show the morphology of the crater. (Credit: Image courtesy of Geological Society Of America)

From Science Daily:

Science Daily (Oct. 15, 2009) — A mysterious basin off the coast of India could be the largest, multi-ringed impact crater the world has ever seen. And if a new study is right, it may have been responsible for killing the dinosaurs off 65 million years ago.

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Volcanoes Wiped Out All Forests 250 Million Years Ago

Trees damaged by the effects of toxic acid rain in the highly polluted area known as the "Black Triangle" are seen in northern Czechoslovakia in 1991. A similar treeless landscape full of wood-eating fungi dominated Earth about 250 million years ago, when acid rain from a volcanic eruption killed off most life on Earth. Photograph by Tom Stoddart/Getty Images

From National Geographic:

Massive volcanic eruptions wiped out the world's forests about 250 million years ago, leaving the planet teeming with wood-eating fungi, according to a new study.

The finding confirms that even hardy trees didn't survive the Permian mass extinction, one of the most devastating losses of life Earth has ever known.

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Animals Survived Apocalypse By Burrowing

Ninety percent of all life was killed during the Permian mass extinction 250 million years ago. But the pig-sized animal Lystrosaurus curvatus and other species apparently survived by burrowing underground. Lunar and Planetary Institute

From Discovery:

When the going gets tough, putting your head in the sand isn't always a bad idea. According to a new study, that's exactly how a group of animals living 250 million years ago survived the worst mass extinction of all time.

In a series of new fossil discoveries in South Africa, researchers have uncovered a slew of petrified burrows, many of them a foot wide and a meter (3.3 feet) or more deep.

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Fresh Impact Risks For Asteroid 'Poster Child'

Still heading our way (Image: Stocktrek Images/Getty)

From New Scientist:

The chances of the asteroid Apophis hitting Earth in 2036 are lower than we thought. But those worried about deep impacts should add a new entry to their calendar: 2068.

When Apophis was first spotted in 2004, the 250-metre-wide rock was briefly estimated to have a 2.7 per cent chance of hitting Earth in 2029. Further observations quickly showed that it will miss Earth that year – but should it pass through a 600-metre-wide "keyhole" in space, it will return to hit Earth in 2036.

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Quick Rebound From Marine Mass Extinction Event, New Findings Show

An artist's rendering of the asteroid impact that took place 65 million years ago and likely killed off nearly every large vertebrate species on the planet, including, many think, the dinosaurs. (Credit: Don Davis/NASA)

From Science Daily:

ScienceDaily (Oct. 3, 2009) — In 1980, Luis Alvarez and his collaborators stunned the world with their discovery that an asteroid impact 65 million years ago probably killed off the dinosaurs and much of the the world's living organisms. But ever since, there has been an ongoing debate about how long it took for life to return to the devastated planet and for ecosystems to bounce back.

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Dinosaur-killing Space Rock Barely Rattled Algae

A close-up view of the 40-centimeter-wide Fish Clay boundary layer. Credit: J. Sepúlveda.

From Live Science:

The asteroid impact that many researchers claim was the cause of the dinosaur die-off was bad news for marine life at the time as well. But new research shows that microalgae – one of the primary producers in the ocean – bounced back from the global extinction in about 100 years or less.

Most of the research on the Cretaceous-Paleogene (K-P) extinction event, previously called the Cretaceous-Tertiary (K-T) event, has involved charting the loss of organisms that had bones or shells.

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New Ancient Fungus Finding Suggests World's Forests Were Wiped Out In Global Catastrophe

An enlarged image of Reduviasporonites. Scientists believe extinct fungus species capitalised on a world-wide disaster and thrived on early Earth. (Credit: Image courtesy of Imperial College London)

From Science Daily:

ScienceDaily (Oct. 2, 2009) — Tiny organisms that covered the planet more than 250 million years ago appear to be a species of ancient fungus that thrived in dead wood, according to new research published October 1 in the journal Geology.

The researchers behind the study, from Imperial College London and other universities in the UK, USA and The Netherlands, believe that the organisms were able to thrive during this period because the world's forests had been wiped out. This would explain how the organisms, which are known as Reduviasporonites, were able to proliferate across the planet.

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Siberian Volcano 'Wiped Out World's Forests' 250m Years Ago

According to scientists a huge Siberian volcano destroyed the
world's forests 250 million years ago Photo: GETTY

From The Telegraph:

A huge Siberian volcano destroyed the world's forests 250 million years ago in what scientists say was the worst extinction event the planet has ever witnessed, new research has disclosed.

It rained fire and acid rain for hundreds of thousands of years and killed 90 percent of all life, including plants and vegetation.

An analysis of ancient fungus that thrives in dead wood has given scientists a window into the event.

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Giant Fish 'Verges On Extinction'

From The BBC:

One of the world's largest freshwater fish is on the verge of going extinct.

A three-year quest to find the giant Chinese paddlefish in the Yangtze river failed to sight or catch a single individual.

That means that the fish, which can grow up to 7m long, has not been seen alive for at least six years.

There remains a chance that some escaped the survey and survive, say experts, but without action, the future of the species is bleak.

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Mass Extinction Event Spared Europe (Mostly)

Moment of Impact
An artist's illustration of the comet crashing into the Yucatan Peninsula. The comet impact that wiped out the dinosaurs had little effect on life in Europe, according to a new study of fossil evidence. NASA

From Discovery News:

When a comet crashed into the Yucatan Peninsula 65 million years ago, all hell broke loose. Scientists have guessed at the scene: a world enshrouded in ashen darkness leftover from the cosmic impact that left almost nothing -- including the dinosaurs -- standing.

But a new study shows that in western Europe at least, the effects were far less terrifying.

Fossil leaves from four million years after the impact show that plants and insects had made a full recovery.

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Asteroid Attack: Putting Earth's Defences To The Test

From New Scientist:

T LOOKS inconsequential enough, the faint little spot moving leisurely across the sky. The mountain-top telescope that just detected it is taking it very seriously, though. It is an asteroid, one never seen before. Rapid-survey telescopes discover thousands of asteroids every year, but there's something very particular about this one. The telescope's software decides to wake several human astronomers with a text message they hoped they would never receive. The asteroid is on a collision course with Earth. It is the size of a skyscraper and it's big enough to raze a city to the ground. Oh, and it will be here in three days.

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Asteroid Attack: Putting Earth's Defences To The Test

Are we prepared for an asteroid strike? (Image: Don Davis/NASA)

From The New Scientist:

IT LOOKS inconsequential enough, the faint little spot moving leisurely across the sky. The mountain-top telescope that just detected it is taking it very seriously, though. It is an asteroid, one never seen before. Rapid-survey telescopes discover thousands of asteroids every year, but there's something very particular about this one. The telescope's software decides to wake several human astronomers with a text message they hoped they would never receive. The asteroid is on a collision course with Earth. It is the size of a skyscraper and it's big enough to raze a city to the ground. Oh, and it will be here in three days.

Read more ....

Flash Recovery Of Ammonoids After Most Massive Extinction Of All Time

Asteroceras, a Jurassic ammonite from England.
(Credit: Courtesy of Wikimedia Commons)

From Science Daily:

ScienceDaily (Sep. 14, 2009) — After the End-Permian extinction 252.6 million years ago, ammonoids diversified and recovered 10 to 30 times faster than previous estimates. The surprising discovery raises questions about paleontologists' understanding of the dynamics of evolution of species and the functioning of the biosphere after a mass extinction.

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Life in the Dark: How Organisms Survived Asteroid Impacts

One of the phototrophs used in the experiment was Chlorella vulgaris.
Credit: Charles University in Prague.

From Live Science:

A dinosaur-killing asteroid may have wiped out much of life on Earth 65 million years ago, but now scientists have discovered how smaller organisms might have survived in the darkness following such a catastrophic impact.

Survival may have depended upon jack-of-all-trades organisms called mixotrophs that can consume organic matter in the absence of sunlight. That would have proved crucial during the long months of dust and debris blotting out the sun, when plenty of dead or dying organic matter filled the Earth's oceans and lakes.

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Survival In A Post-Apocalypse Blackout

Surviving a blackout (Image: WestEnd61/Rex Features)

From New Scientist:

NATURAL catastrophes such as asteroid impacts, massive volcanic eruptions or large-scale wildfires would have periodically plunged our planet into abnormal darkness. How did life survive without the sun's life-giving rays during such episodes? With a little help from organisms that can switch to another source of energy while they wait for sunlight to pierce the darkness once more.

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NASA Falling Short of Asteroid Detection Goals

The team says it is almost certain that a large Baptistina fragment created the 180km Chicxulub crater off the coast of the Yucatan 65 million years ago. The impact that produced this crater has been strongly linked to the mass extinction event that eliminated the dinosaurs. Image from The BBC.

From Wired Science:

Without more funding, NASA will not meet its goal of tracking 90 percent of all deadly asteroids by 2020, according to a report released today by the National Academy of Sciences.

The agency is on track to soon be able to spot 90 percent of the potentially dangerous objects that are at least a kilometer (.6 miles) wide, a goal previously mandated by Congress.

Asteroids of this size are estimated to strike Earth once every 500,000 years on average and could be capable of causing a global catastrophe if they hit Earth. In 2008, NASA’s Near Earth Object Program spotted a total of 11,323 objects of all sizes.

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