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New Theory Explains Periodic Mass Extinctions
i_like_spam writes "The theory that the dinosaurs were wiped out by an asteroid impact, the K-T extinction, is well known and supported by fossil and geological evidence. Asteroid impact theory does not apply to the other fluctuations in biodiversity, however, which follow an approximate 62 million-year cycle. As reported in Science, a new theory seems to explain periodic mass extinctions. The new theory found that oscillations in the Sun relative to the plane of the Milky Way correlate with changes in biodiversity on Earth. The researchers suggest that an increase in the exposure of Earth to extragalactic cosmic rays causes mass extinctions. The original paper describing the findings is available online."
The article suggests that this does not explain the K-T event, which is already adequately explained by the asteroid impact theory. This theory explains the cyclical decreases in biodiversity that seem to happen about once every 62 million years. The K-T event is not part of this cyclical pattern.
The title of the summary is totally wrong. This has nothing to do with mass extinctions. Its looking at fossil Species and Family counts vs time correlated with Solar motion. The 62 MY cycle barely touches the Mass extinction events.
Better summary title - "Life's Diversity changes with Solar Galactic Orbit". Or something like that.
You forgot to mention Christopher Columbus's theory that the earth is round... [...]when the rest of the so called "Intelligent" people of the world said it was flat.
LOL! You still believe that nursery school myth?
NO intelligent person in Columbus's time thought the world was flat -- as it clearly is not to anyone sufficiently observant. Columbus's problem is that he wanted to go to Asia via a western route, and everyone intelligent knew that with a circumference of about 25,000 miles, Eratosthenes having calculated it about 240 BC (as others had since). Hence they "knew" that with the sailing technology of the day, there was no way Columbus could make the voyage.
They were right, too. Had the Americas not been in his way, his expedition would have perished before he got as far as the longitude of Hawaii.
There is some evidence that Columbus may in fact have known that there was some land mass to the west considerably before Asia (the Vikings certainly did, and it is quite possible that fishermen who went as far as the Grand Banks were also aware). Whether from that he decided that Eratosthenes was wrong and the circumference was smaller (possibly influenced by Ptolemy's maps (from Geographica) which underestimated the circumference at about 18,000 miles), or whether he was just arguing that way to get backing for an expedition (with the secret purpose of discovering and exploiting just whatever land mass was there), we have no way of knowing.
That mistake alone discredits the rest of your post as to make it not even worth reading.
-- Alastair