Posted on 10/11/2006 11:43:56 PM PDT by MadIvan
If you are the kind of person who worries about the future, this might not make happy reading.
Scientists have found that on average mammal species enjoy only 2.5 million years of life before being wiped out because of the Earth's "wobble."
They say when the tilt and orbit reach key points it can spark dramatic global cooling - and the last time this happened was 2.6 million years ago.
This suggests we are overdue a wave of extinction.
However, before you panic, scientists say our planet has changed beyond all recognition in the last 3 million years.
The new research published in the journal Nature (must keep) however sheds new light on just why individual mammal species seem to come and go with mysterious regularity.
The study, conducted by researchers at Utrecht University in the Netherlands, involved looking at 22 million years of data on rodent species to see which ones appeared and died out at key points.
They then studied the pattern of the Earth's wobble, which is caused by two factors, our orbit around the sun and the tilt of the planet.
Both of these can be slightly altered by the gravitational pull of other planets, in the case of the tilt it can adjust by as much as two degrees, and the orbit can vary from a circle to an ellipse.
Lead researcher Dr Jan van Dam said when the tilt reaches a certain point and the orbit is almost a perfect circle it can trigger ice sheet expansion.
This could then lead to colder summers, changes in humidity and significant climate cooling.
He found a clear pattern between the Earth's wobble and mammal species dying out.
There were two distinct cycles of species turnover, one with peaks every 2. 5 million years and the other every million years.
Dr van Dam said the last peak was 2. 6 million years ago.
However he said this does not necessarily mean we are on the brink of dramatic global cooling.
'The last three million years are not representative of those we studied,' he said.
"Northern hemisphere glaciation is fully developed and that also affects the climate system."
He said global warming and destruction of habitats could also change the patterns of the past.
He also thinks people may well be able to survive global cooling, give the way our ancestors coped with past Ice Ages.
"Humans have survived ice ages which were quiet extreme and are well adapted to survival," he said.
Based on the fossil record it appears on average we have lost around 10 to 100 species - including insects, bacteria, fungi and mammals - each year.
There are currently around 5,000 known species of mammal at present and in the past 400 years 89 mammals have died out.
I wonder if during a magnetic pole transition there will be any increase in radiation at the surface. Is our atmosphere enough to protect us? I know lots of charged particles are deflected around Earth. Will we be ok but all our satellites hosed?
How can you tell if the plates are Teutonic? Blond hair and blue eyes?
More use of the furnace, less use of the A/C. It works out. ;-)
Gore gave a speech in Fargo, ND, where he blamed that year's seasonal flooding in the Red River Valley on global warming...
Yeah, right, Al. We call that "spring" in these parts...
He has been beating that drum for a long time, the epitomy of "Stuck on stupid".
Makes you wonder why these ancient advanced cultutres built huge stone monuments. Maybe to hide in during earth changes.
For all the science about wobbling orbits and changing axis tilt, I have never seen anyone show what part of the cycle(s) we are in now and what are the projections for the future.
Clearly the ice age cycles are caused in part due to changes in Earth's orbit, tilt, precession.
But where are we NOW is the question?
There are three types of people:
those who don't know,
those that don't know they don't know
and those that know they don't know but get paid big bucks to act like they do know.
News flash: We are all going to die someday.
So what humans do can change the tilt and orbit of the earth?
Another end of the world story.
take me now : )
Shucks, and there I was expecting to live 3 million years, what a disapointment...
Please control yourself, you are on a public forum :)
as i hit send, i FIGURED you were going to take that personally! ; )
The interesting thing about this...is that this is material that a environmentalist won't touch. It has nothing to do with their "science" or agenda. Yet, it probably has more to explain about our earth...than anything else out there today.
LOL....Sorry about the typo. Yes they were Germans who caused it. It is the cause of the earthquakes in Caulifornia!
don't know why I put a "u" in for a "c"....should have been "tectonic" not "teutonic"
Thank you...
I do too have a life!!
Not to be frivolous, this could well happen, but there's sod all I or anyone can do about it if it does.
I am left thinking of a commercial from a few years back for Basset's Jelly Babies - they, apparently, are in a wibbly wobbly world of their own, not unlike the average liberal.
This is the wobbliest thing I could find ... http://www.youtube.com/watch?v=EQ2dQt_Ex-0
Is it wrong that I am now giggling?
Al Gore's mass is the primary cause of Global Wobble.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.