On the fifth of this month I posted Supernovae, Comets and Holey Mammoth Tusks, about a recently-developed theory with apparently lots and lots of confirming evidence, that purported to demonstrate the mass extinction of North American megafauna – wooly mammoths, giant bison, saber-tooth cats, etc. – was the result of effects from a supernova explosion 250 light years from earth, and a 10-kilometer wide comet produced that hit or exploded just above Chicago nearly 13,000 years ago.

Well, this week researchers from the University of Bristol say they have disproven that theory, by examining charcoal and pollen records for the great fires the comet must have caused. Their results, they say, provide no evidence of continental-scale fires. Though they do say their examination of this material dated between 15,000 and 10,000 years ago, somehow establishes that an increase in large-scale wildfires all over the world during the past 10 years is attributable to global warming.

Ah, well. So much for grand theories about great and sudden climate change in past ages, as well as ongoing disagreements about climate change in the current age. Perhaps what is best to be learned from this back and forth of disagreements about evidence and what it means is to take the pronouncements of various groups of scientists with a grain of salt, for their conclusions are often so short-lived as to not even make it past the publication schedule of two successive issues of the same journal!

Eventually, maybe, they’ll work it all out.

And while we’re here looking at research from different sources that can end up with entirely different conclusions, check out a new project site from Creative Commons – ScienceCommons. Making the Web work for science, to develop technologies to make research, accumulated data and materials easier to find and use. I’ll be reporting on this again in the near future, so stay tuned!

Links:

Supernovae, Comets and Holey Mammoth Tusks
North American Comet Impact Theory Disproved
ScienceCommons

Blue Sky Studios

Not so very long ago the wizened gatekeepers of scientific orthodoxy staged a vigorous and extremely nasty campaign designed to prevent any possibility that impressionable science students or the great unwashed masses might come to suspect that things in our cosmic neighborhood were ever anything but perfectly peaceful, perfectly ordered, and perfectly safe. It was the middle of the 20th century, a bit over 150 years since the staid scientists at the Royal Society in London had discovered the hard way that stones really can fall from the sky despite their pronouncements to the contrary.

Yet the publication of Worlds in Collision in 1950 – and Ages in Chaos in 1952 – purported to demonstrate that the Earth had suffered some serious cosmic upheavals within the memory of human civilizations. These ideas drove such astronomical lions as Harlow Shapley to use every underhanded method and scheme available to destroy the author and reassure the public once again that, despite all evidence and witness through the ages, stones do NOT fall from the sky, comets do NOT wreak havoc on the Earth, and the perfect clockwork of cosmic orderliness is NOT violated by disorderly events. Thus did the notorious Velikovsky Affair take its place in the annals of science’s ample history of internal turf wars.

Many young people today are quite used to the idea that our planet has been bombarded by cosmic billiard balls of one sort or another, learning about the epochal events that marked transitions from one age to another, usually by causing mass extinctions of life forms and altering the course of evolution. Even children’s books and movies portray the catastrophic events of 65 million years ago when a large asteroid ended the age of the dinosaurs. Yet apart from those now-recognized disasters in the distant past of our planet, scientists have tended to remain skeptical of the notion that such world-shattering events have ever occurred – or been recorded – in the short (~100,000 year) history of human beings on this planet.

Archaeologists, geologists and paleontologists do know that there was a mass extinction of megafauna such as wooly mammoths, giant bison, saber-tooth tigers, etc. in North America and Siberia just 13,000 years ago, when early Americans of the Clovis culture were known to hunt these huge mammals. Some scientists believed that they were driven to extinction by a drastic climate change that began the last ice age, others believed those early human hunters had driven their prey to extinction. But over the last few years a new narrative that reads like a fine detective novel has come to the fore, and it begins with the death of a nearby star 41,000 years ago.

In 2005, nuclear scientist Richard Firestone of the Lawrence Berkeley National Laboratory published research findings that linked the extinction of the mammoths with the supernova explosion of a star just 250 light years from Earth. The initial shockwave hit our planet 34,000 years ago, evidenced by tiny impact craters on mammoth tusks from that time, produced by iron-rich grains that bombarded the Earth at 10,000 kilometers per second. More debris from the explosion was said by the researchers to have formed a comet approximately 10 kilometers in diameter, which hit the Earth 13,000 years ago and caused the extinction.

Now another team of scientists led by anthropologist Douglas Kennett also conclude that a comet was responsible for the extinction of North American megafauna, and have even pinpointed the impact site to somewhere close to Chicago. The event caused an ice age along with the extinction of the giant mammals and disappearance of the human culture that relied upon them for sustenance.

There is of course no universal consensus about this theory despite evidence from many scientific fields, but the authors have stated that a collision so recent in human history underscores the importance of trying to detect and deflect cosmic debris that may be coming our way. And, in the end, we do now know that things are not nearly so peaceful and serene in our neck of the galaxy as scientists once assumed.

Links:

Supernova Explosion May Have Caused Mammoth Extinction
Scientists Say Comet Killed Off Mammoths, Saber-Toothed Tigers

Using statistics going all the way back to 1970, Susan Cutter and Kevin Borden of USC created the map to enable emergency management planners to examine various natural hazard risks to populations all over the country. These are deaths by floods, earthquakes, tornadoes, hurricanes, extreme temperatures and other natural (but violent) causes.

The full publication from the International Journal of Health Geographics is available as a pdf at Spatial patterns of natural hazards mortality in the United States. But here’s a sneak preview… what’s your county’s ‘death-by-natural-hazard’ risk look like?

1918 Flu Antibodies Resurrected from Elderly Survivors

Back in 2005 some researchers journeyed to the Alaskan permafrost to dig up some bodies of victims of the 1918 Spanish flu pandemic that killed 50-100 million people worldwide as World War 1 came to a close. They were able to recover the virus from these bodies because they have been frozen since burial.

Now researchers at Monroe Carell Jr. Children’s Hospital at Vanderbilt have recovered antibodies against this deadly flu virus from survivors of the pandemic. They collected blood samples from 32 survivors age 91 to 101, and found that all samples reacted to the virus – indicating that immunity has been preserved for 90 years. This represents the longest immune system ‘memory’ thus far observed.

The real test came when researchers at the CDC infected mice with the 1918 influenza and then administered the antibodies. Those receiving the lowest dose of antibodies died, all mice given the highest dose survived. The “extremely rare” B cells that produced the antibodies in all the survivors’ blood are some of “the most potent antibodies ever isolated against a virus,” and may prove invaluable against other viruses or for developing new antibodies against expected future pandemics.

Japanese researchers have developed a New Automated System to identify victims of mass disasters. The type of disasters that usually end up with nothing but dental records for identification (if not DNA)… airplane crashes, suicide bombings, building collapses and such, where the victims come in small pieces, usually charred to a crisp.

The new system is a novel dental x-ray matching system that reduces the real-time input of forensic experts puzzling over parts of jaws and improves the accuracy of the results at the same time. Which is of course ‘good’ for the relatives of those victims waiting for something to bury with full honors in the family plot.

Mass disasters happen in this modern world, both natural and unnatural. Nearly 3,000 people died when terrorists flew planes into the Twin Towers in 2001, and the grizzly scenes of bombings in the Middle East are standard daily fare on the news. There are also earthquakes, tsunamis, floods and cyclones that kill hundreds or thousands at a time, not all of them found inside a home where it’s pretty easy to guess who they were.

This new Japanese system can make a positive match in less than 4 seconds. Let’s face it – that’s a lot faster than any of us as next-of-kin could identify a piece of jaw as belonging to someone we’ve known all their lives. And that can be a good thing for those left behind.

Link:
New Automated System IDs Victims of Mass Disasters in Minutes