Naked Science Forum

Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: Bass on 29/03/2005 19:03:20

Title: Mass Extinctions every 62 million years
Post by: Bass on 29/03/2005 19:03:20
http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2005/03/10/MNGFIBN6PO1.DTL

This article appeared in the San Francisco Chronicle March 10.  Anyone have a hypotheis?  Permian extinction (~250 my) may be related to Siberian Traps- possibly the largest outpouring of lava (basalt) since the PreCambrian.
Title: Re: Mass Extinctions every 62 million years
Post by: ADD HAHAHA on 06/04/2005 04:05:28
there is a new theory that when the meteor that kill the dinisors hit dust was throne in2 the air n the dust magnifide the sun so the atmousphere became like 1000 degrees f n burn the dinosors 2 death.....

happy ending huh [:D]
Title: Re: Mass Extinctions every 62 million years
Post by: Bass on 06/04/2005 05:46:49
One big bar-b-que, eh?

Prediction is difficult, especially the future.  -Niels Bohr
Title: Re: Mass Extinctions every 62 million years
Post by: ADD HAHAHA on 06/04/2005 17:57:09
lol
Title: Re: Mass Extinctions every 62 million years
Post by: chimera on 06/04/2005 22:55:09
quote:
Originally posted by Bass

http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2005/03/10/MNGFIBN6PO1.DTL

This article appeared in the San Francisco Chronicle March 10.  Anyone have a hypotheis?



Nonsense about it being tardy, though. It runs like clockwork. [:D]

The Solar system passes through the exact plane of the galaxy in december 2012, so in only 7 years we'll see if that has any consequences, as some do think it will, since that is a very, very rare occasion. Funny enough the Mayas also knew this and their calendar stops at that point. They just throw in the towel after that date, and expect some galactic chairdance of sorts.

We're so very fortunate to sit first row. Maybe it will make the Earth's magnetic field do a full flip-flop. Gosh, must be some spectacle.
Title: Re: Mass Extinctions every 62 million years
Post by: akuba on 30/04/2005 05:28:11
Yea well, the mayas also gave blood from their genitals...
Title: Re: Mass Extinctions every 62 million years
Post by: chimera on 30/04/2005 10:52:06
quote:
Originally posted by akuba

Yea well, the mayas also gave blood from their genitals...



Which ofcourse is a lot sillier than having it pierced with so much iron-ware your willy wonka works like a showerhead... (I sh*t thee not)

Added: Mayan culture indeed looks more like an alien culture than human, at times. On the other hand, say we discovered real aliens: would you discard their astronomy as easily because of their weird habits?

Your loss, I think.
Title: Re: Mass Extinctions every 62 million years
Post by: realmswalker on 03/05/2005 05:35:44
hmm well the article says that every 62 million or so years a mass extinction occurs...its been 65million since the last...and we are currently experiancing another one...soooo id agree with these scientists(eh 3 milion years off doesnt matter, that within like 5% accuracy or so...)
Title: Re: Mass Extinctions every 62 million years
Post by: michaellaver on 11/07/2005 01:13:12
First I like to say that I am no expert I only have an interest and a possible theory. My theory challenges the theories of mass extinction. One thing common on every mass extinction is that not all life dies and always after each extinction there is a more advanced life form.  If there was true mass extinction why hasn’t all life been wiped out, not just the life that cannot survive in the new environment.

I believe that extinctions are not extinctions at all but a more advanced species that has appeared and is competing better for the available food supplies. This may be because a new food source has become available meaning the species design can be altered. Generally a new food source from plants will be of higher nutritional value meaning that herbivores can develop faster more agile bodies. The carnivores must also develop to catch these herbivores. Those that do not develop die out. A classic evolution scenario where life has advanced and extinction has occurred.

What appears to be a major extinction might occur when any animal, plant, fish or bird that makes a significant advancement in design which might result in many other species of the same or different kind being affected.

The result is a more diverse range of life on earth as many of the older species are able to continue with life as their own life is not affected by this new species but those species which are affected by the new species are not able to compete. A situation we currently have on earth the wide variety of life with some species  that have been around since early life, some since the dinosaurs and some which is new.
 
The concept mentioned in the article http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2005/03/10/MNGFIBN6PO1.DTL about mass extinction every 62 million years may well be true and occurring right now. Using my theory and considering that the human being as the most advanced species, then look at the pressure we are putting on the wild animals of the earth. We are destroying their habitats for a place to live ourselves or to make our lives better. Maybe in the future most other life will become extinct except for that life we require to keep our own lives functioning.

This theory also fits in with how life on earth is becoming much more advanced. I.e.  First vertebrates Ă  First amphibians Ă  First dinosaurs > First Mammals > First Birds > First Apes > First Intelligent Life.

We shouldn’t live in fear of extinction as each step (extinction) has been a step forwards not extinction and a start again.
Title: Re: Mass Extinctions every 62 million years
Post by: Bass on 14/07/2005 02:03:24
Humans as the most advanced life and the first intelligent life???

Methinks thou creditith homo sapien overly much.

Prediction is difficult, especially the future.  -Niels Bohr
Title: Re: Mass Extinctions every 62 million years
Post by: gsmollin on 19/07/2005 19:02:04
The gaunt fact remains that we are in the middle of a great extinction. The real question is this : Will we survive it? Remember that the last one killed the dinosaurs, who had survived 100x longer than us on the planet. Maybe the future holds promise for intelligent rats.
Title: Re: Mass Extinctions every 62 million years
Post by: beaglethorp on 27/07/2005 03:21:50
Sometimes this may indeed be the reason for mass extiction. For example, it is thought that the first oxegen producing organisms may have had quite a nasty affect on the environment. They probably had a poisoning affect on much of earths life and even possibly caused a "snowball earth" to form.
http://www-eps.harvard.edu/people/faculty/hoffman/snowball_paper.html

However, we know for a fact that very high energy collisions with the earth have happened in the past and will happen in the future(minus any intervention from humans). Some of these collisions are so catastophic that is is truley a testiment to the tenacity of life that anything survives at all. This is all you need to consider to conclude your theory must be at least partially wrong.

quote:
Originally posted by michaellaver

First I like to say that I am no expert I only have an interest and a possible theory. My theory challenges the theories of mass extinction. One thing common on every mass extinction is that not all life dies and always after each extinction there is a more advanced life form.  If there was true mass extinction why hasn’t all life been wiped out, not just the life that cannot survive in the new environment.

I believe that extinctions are not extinctions at all but a more advanced species that has appeared and is competing better for the available food supplies. This may be because a new food source has become available meaning the species design can be altered. Generally a new food source from plants will be of higher nutritional value meaning that herbivores can develop faster more agile bodies. The carnivores must also develop to catch these herbivores. Those that do not develop die out. A classic evolution scenario where life has advanced and extinction has occurred.

What appears to be a major extinction might occur when any animal, plant, fish or bird that makes a significant advancement in design which might result in many other species of the same or different kind being affected.

The result is a more diverse range of life on earth as many of the older species are able to continue with life as their own life is not affected by this new species but those species which are affected by the new species are not able to compete. A situation we currently have on earth the wide variety of life with some species  that have been around since early life, some since the dinosaurs and some which is new.
 
The concept mentioned in the article http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2005/03/10/MNGFIBN6PO1.DTL about mass extinction every 62 million years may well be true and occurring right now. Using my theory and considering that the human being as the most advanced species, then look at the pressure we are putting on the wild animals of the earth. We are destroying their habitats for a place to live ourselves or to make our lives better. Maybe in the future most other life will become extinct except for that life we require to keep our own lives functioning.

This theory also fits in with how life on earth is becoming much more advanced. I.e.  First vertebrates Ă  First amphibians Ă  First dinosaurs > First Mammals > First Birds > First Apes > First Intelligent Life.

We shouldn’t live in fear of extinction as each step (extinction) has been a step forwards not extinction and a start again.




beaglethorp
Title: Re: Mass Extinctions every 62 million years
Post by: David Sparkman on 28/07/2005 20:58:47
Asminov speculated on cosmic dust in one of his many stories as a cause for turning a sun into a supernova. A dust cloud rich in carbon was pulled into the star and accelarated the H -> He -> C -> Fe process, or so the story goes.

The same concept (cosmic dust) might account for periodic cold periods on the order of 68 million years. Say the sun in its rotation through space on this spiral arm, occassionally meets with dirty space that dims out the sun by a fraction of a percent. We could see a major cooling trend i.e. ice age for all the time it took to transverse the dust cloud, clean up the stuff that tagged along on gravity, and finally wait for a major vocano erruption to dirty the ice pack and initiate global warming.

There is still so much we don't know. As far as stopping global warming, I think we should first practice stopping the tide from coming in, before we try something as important as being a god. No telling how much we will mess up by fixing something that ain't really broke...

David
Title: Re: Mass Extinctions every 62 million years
Post by: Evie on 28/07/2005 22:54:49
Periodicity is a popular topic nowadays. Scientists tend to quibble about the exact number of years, and the magnitude of the extinctions.  David M. Raup, for instance, claims there is a 26 million year periodicity to extinctions. His models show a better-than-statistically-average fit of extinction events to the 26 my cycle.  Walter Alvarez and Rich Muller published a 28 my peridicity for meteor impact craters. Magnetic reversals purportedly occur about every 30 my, though the rate of reversals appears to slow down and speed up over a larger scale. Astronomical events have periodicity, due to the fairly regular movements of planets and galaxies, etc. "The Galaxy rotates completely about its axis every few hundred million years, our solar system oscillates up and down through the Galaxy in tens of millions of years..."

Also, as to the magnitude of extinctions, the K-T Extinction (the one that wiped out the dinosaurs) was relatively small. The Permian Extinction (~250 mya), however, is estimated to have wiped out up to 96% of all living organisms, almost a complete destruction of life. There have been many theories for the cause of such a massive extinction. In 1962, Otto Schindewolf published a paper hypothesizing a supernova as the cause. There was also a substantial drop in sea level at the end of the Permian.

The views favored by more conservative scientists concerning extinction events is that there are often a combination of factors that lead to a species' extinction, and that a catastrophic event often serves as the proverbial straw that broke the camel's back, or as an instigating factor toward decline.

Extinctions are occuring all the time, but a mass extinction event is characterized by the generally accepted figure of twice as many extinctions as the background level. According to that, we are indeed in a period of mass extinction at this time. However, this period of extinction is largely due to human influence, not some astronomical periodic anomaly. For a great book on this subject, I refer you to "The Song of the Dodo" by David Quammen (I posted a topic referring to this book called "Island Biogeography").

If you're interested in some very sensational ideas, pick up David M. Raup's "The Nemesis Affair." I'm not entirely sure of his theories, but he seems to have put together a lot of interesting research nonetheless.

I like to lick rocks....
Title: Re: Mass Extinctions every 62 million years
Post by: A Big Mug on 22/11/2005 02:44:51
It is a pleasure to see nobody offer up the name Dick Cheney as a reason for the mass extinction.