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Study Links Extinction Cycles to Changes in Earth’s Orbit and Tilt (Not man made global warming?)
NY Times ^
| October 12, 2006
| JOHN NOBLE WILFORD
Posted on 10/12/2006 1:51:19 PM PDT by neverdem
If rodents in Spain are any guide, periodic changes in Earths orbit may account for the apparent regularity with which new species of mammals emerge and then go extinct, scientists are reporting today.
It so happens, the paleontologists say, that variations in the course Earth travels around the Sun and in the tilt of its axis are associated with episodes of global cooling. Their new research on the fossil record shows that the cyclical pattern of these phenomena corresponds to species turnover in rodents and probably other mammal groups as well.
In a report appearing today in the journal Nature, Dutch and Spanish scientists led by Jan A. van Dam of Utrecht University in the Netherlands say the astronomical hypothesis for species turnover provides a crucial missing piece in the puzzle of mammal species- and genus-level evolution.
In addition, the researchers write, the hypothesis offers a plausible explanation for the characteristic duration of more or less 2.5 million years of the mean species life span in mammals.
Dr. van Dam and his colleagues studied the fossil record of rats, mice and other rodents over the last 22 million years in central Spain. The fossils are numerous and show a largely uninterrupted record of the rise and fall of individual species. Other scientists say rodents, thanks to their large numbers, are commonly used in studies of such evolutionary transitions.
As the scientists pored over some 80,000 isolated molars, the most distinct markers of different species, the patterns of turnovers emerged. They seemed often to occur in clusters, which seemed unrelated to biology.
--snip--
The longer-term cycle, the scientists determined, peaks when Earths orbit is closer to being a perfect circle.
--snip--
The pulses of turnover, the scientists determined, occurred mainly at times when the different cycles left Earth a colder world.
(Excerpt) Read more at nytimes.com ...
TOPICS: Culture/Society; Extended News; Front Page News; News/Current Events
KEYWORDS: earth; globalwarming; milankovitchcycles; paleontology; science; spain
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To: neverdem
I live in northern Ohio and it's been snowing on and off today even though the lake is still pretty warm. I wonder if Algore can tell me why.
21
posted on
10/12/2006 2:19:24 PM PDT
by
Right Wing Assault
("..this administration is planning a 'Right Wing Assault' on values and ideals.." - John Kerry)
To: Tench_Coxe
Wow! You are on top of things.
Now, you have to pick a cool place to have your conference, so people can refer to The _____ Conference, and later The ____ Global Tilt Treaty.
SUVs cause more global tilt because their center of gravity is higher than that of hybrids or electrics, plus the transaxle is off-center, resulting in torque.
Everyone agrees, their is no dissent except from a few on FreeRepublic (who took time out from preventing Dixie Chicks ticket sales).
22
posted on
10/12/2006 2:20:30 PM PDT
by
DBrow
To: neverdem
To: Tench_Coxe
Nope, soon it will be 'man made global tilt'. And the US will be framed as having the most obese people, because of its wealth, and needs to redistribute it to other countries to even out the weight balance.
1000 'scientists' will sign a document making a consensus that there is no doubt. I'd be willing to send all my lose change (since it weighs more than paper money) to whatever part wasn't weighing enough to balance us out.
24
posted on
10/12/2006 2:30:42 PM PDT
by
DejaJude
(Admiral Clark said, "Our mantra today is life, liberty and the pursuit of those who threaten it!")
To: Kerretarded
Dimly from a past thread.
"I heard that the world is just a bunch of crazy, unexplainable, mixed up things, and that just when we are about to get it figured out, BANG, it changes to a new set of crazy, unexplicable things.
And I heard it already happened once or twice."
25
posted on
10/12/2006 2:38:13 PM PDT
by
UCANSEE2
(It's turtles all the way down.)
To: El Gato; Ernest_at_the_Beach; Robert A. Cook, PE; lepton; LadyDoc; jb6; tiamat; PGalt; Dianna; ...
26
posted on
10/12/2006 3:23:41 PM PDT
by
neverdem
(May you be in heaven a half hour before the devil knows that you're dead.)
To: RadioAstronomer
also interesting... and not -as yet- yekintrepped.
27
posted on
10/12/2006 3:33:43 PM PDT
by
King Prout
(many complain I am overly literal... this would not be a problem if fewer people were under-precise)
To: neverdem
To: areafiftyone; bigbob
Actually I'm SURE it;s because of Haliburton and Enron . . .
29
posted on
10/12/2006 3:36:26 PM PDT
by
homemom
("Never place a period where God has placed a comma." Gracie Allen)
To: UCANSEE2
30
posted on
10/12/2006 3:37:05 PM PDT
by
homemom
("Never place a period where God has placed a comma." Gracie Allen)
To: Renfield
Yep. I do remember reading about this. Elliptal orbits and all that. Thanks.
31
posted on
10/12/2006 5:00:12 PM PDT
by
b4its2late
(I'm not insensitive, I just don't care.)
To: DBrow
SUVs cause more global tilt because their center of gravity is higher than that of hybrids or electrics, plus the transaxle is off-center, resulting in torque. Everyone agrees, their is no dissent except from a few on FreeRepublic (who took time out from preventing Dixie Chicks ticket sales). You have the right idea but should have carried your study a bit further. Actually, 1950s-1960s muscle cars caused global tilt because of the power generated to the rear wheels causding the axis of the earth to shift. We need to export old muscle cars to other countries so they can bring the earth back on line!
32
posted on
10/12/2006 6:05:32 PM PDT
by
calex59
(Hillary Clinton is dumber than a one eyed monkey with a brain tumor(credit to Harley69))
To: calex59
An excellent idea- the General riding the streets of Teguicigalpa brings tears to my eyes.
We should disable the forward gears, so that we can udo the terrible damage capitalism has wrought on Earth.
33
posted on
10/12/2006 6:35:00 PM PDT
by
DBrow
To: Renfield
"Milankovich cycles".Amazing how no one in the MSM seems to realize that the Earth "wobbles," just like a spinning top and that our planet's surfaces are never at a steady angle to the Sun.
34
posted on
10/12/2006 6:51:15 PM PDT
by
Kenny Bunk
(What does it matter if we’re all dead, as long as the French respect us.)
To: Right Wing Assault
Let's hope it doesn't depress Republican turnout.
35
posted on
10/12/2006 6:52:27 PM PDT
by
Kenny Bunk
(What does it matter if we’re all dead, as long as the French respect us.)
To: neverdem; All
WARNING! MORE THAN A LAUGH-A-MINUTE...
Hilarious FReeper humor bump!
36
posted on
10/12/2006 7:56:28 PM PDT
by
PGalt
To: neverdem
I understand that Algore discovered this orbital fluctuation 45 years ago and typed up his notes at that time, using his Dell computer with Windows XP.
37
posted on
10/12/2006 8:47:24 PM PDT
by
Rembrandt
(We would have won Viet Nam w/o Dim interference.)
To: nhoward14
"We're all gonna die!!!!!!!!!!!!!"
Yes, we are.
And if that fact changes, please remember to ping me.
38
posted on
10/12/2006 10:01:31 PM PDT
by
StJacques
(Liberty is always unfinished business)
To: neverdem; All
I cannot find my NYT login password -- please don't shoot me for having one, I hate the NYT as much as any of you -- so may I just ask, does this article trace long-term global warming cycles to "
Equinoctal Precession"? I saw "Milankovitch Cycles" mentioned earlier, which addresses the climatic changes of Equinoctal Precession.
Just wondering.
39
posted on
10/12/2006 10:09:14 PM PDT
by
StJacques
(Liberty is always unfinished business)
To: StJacques
I cannot find my NYT login password -- please don't shoot me for having one, I hate the NYT as much as any of you -- so may I just ask, does this article trace long-term global warming cycles to "Equinoctal Precession"?No, only the news@nature.com link mentioned Milankovitch oscillations. I saved it as "Milankovitch Cycles" for any future keyword search.
40
posted on
10/12/2006 10:23:45 PM PDT
by
neverdem
(May you be in heaven a half hour before the devil knows that you're dead.)
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