A new view of mass extinctions... (Endings)
by xeno6696 
, Sonoran Desert, Tuesday, June 30, 2009, 18:44 (5623 days ago)
Like Kuhn said... differing views create new ideas. - http://seedmagazine.com/content/article/the_extinction_oscillator/
A new view of mass extinctions...
by David Turell , Wednesday, July 01, 2009, 05:58 (5623 days ago) @ xeno6696
Like Kuhn said... differing views create new ideas. > http://seedmagazine.com/content/article/the_extinction_oscillator/ - I wonder if the supposed cycles of the article relate in any way to the Malankovitch orbital cycles? - http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm - There have been six major extinctions, the last 65 million years ago with the dinosaurs. That alone does not seem to fit their timetable of cycles if I have followed their line of reason properly.
A new view of mass extinctions...
by xeno6696 , Sonoran Desert, Wednesday, July 01, 2009, 14:00 (5622 days ago) @ David Turell
Dr. Turell, - What they're talking about is the sun bobbing through the central plane of the milky way. When it's on the topside of the disc--that's when we're bombarded with more cosmic rays, due to the backlash of a cluster we're hurtling towards. I'm not familiar with the geologic timing of the mass extinctions, so I'm not too informed about the breadth of the article. But it's a highly imaginative idea.
A new view of mass extinctions...
by David Turell , Wednesday, July 01, 2009, 14:40 (5622 days ago) @ xeno6696
What they're talking about is the sun bobbing through the central plane of the milky way. When it's on the topside of the disc--that's when we're bombarded with more cosmic rays, due to the backlash of a cluster we're hurtling towards. - Matt: I understood that. I was pointing out that there are more cycles than they took into account and they didn't relate their findings to the geologic timing of extinctions. Some one should amalgamate all of the cycles and we might find something interesting.
A new view of mass extinctions...
by xeno6696 , Sonoran Desert, Thursday, July 02, 2009, 04:15 (5622 days ago) @ David Turell
What they're talking about is the sun bobbing through the central plane of the milky way. When it's on the topside of the disc--that's when we're bombarded with more cosmic rays, due to the backlash of a cluster we're hurtling towards. > > Matt: I understood that. I was pointing out that there are more cycles than they took into account and they didn't relate their findings to the geologic timing of extinctions. Some one should amalgamate all of the cycles and we might find something interesting. - Acknowledged. - How many mass extinctions are on record?
A new view of mass extinctions...
by John Clinch , Thursday, July 02, 2009, 11:42 (5621 days ago) @ xeno6696
I did think there were five, although the 62m-year hypothesis would suggest more. The consensus view is that we are currently undergoing a sixth, caused by the ravages of Mankind. - A fascinating theory, though.
A new view of mass extinctions...
by David Turell , Thursday, July 02, 2009, 14:31 (5621 days ago) @ xeno6696
How many mass extinctions are on record? - Six
A new view of mass extinctions...
by David Turell , Thursday, July 02, 2009, 16:28 (5621 days ago) @ David Turell
How many mass extinctions are on record? > Six - Didn't mean to be so brief but John Clinch added some info regarding six and I thought this site might want to hear from Niles Eldridge: - http://www.actionbioscience.org/newfrontiers/eldredge2.html
A new view of mass extinctions...
by xeno6696 , Sonoran Desert, Friday, July 03, 2009, 22:37 (5620 days ago) @ David Turell
Dr. Turell, - Interesting. Though I do not think conservation can be successful in its ultimate goal. The coming climate change (whether one wants to debate it being man-made or not is pointless) guarantees an irrevocable change in how life will exist on this earth. If all countries agreed to carbon caps it would still take several hundred years for those efforts to bear fruit. Essentially, it is too late. I know this sounds defeatist, but conservation means you're putting out fires instead solving oncoming problems. Man should let this extinction take its course and plan for how we will exist if 90% of all species dies. - This means we should create a metric for how much energy (in terms of both food and power/gas etc.) would be the minimum acceptable value, and we will have to modify our energy consumption structures to be in line with it. - Part of why I say this is the fact that consumerism is not going to disappear. The kind of change that some environmentalists call for would require nations to completely switch to a different paradigm, and while I AM a futurist, I've also spent alot of time studying change management (my undergrad degree is on applying technology to problems) and I can tell you that some changes require a social paradigm shift. The way to change course in something like this is in a grass roots movement... but these are necessarily slow because it relies entirely upon cultural diffusion. - So to me, this means that the solution is going to have to be one of human engineering.
A new view of mass extinctions...
by George Jelliss 
, Crewe, Saturday, July 04, 2009, 17:20 (5619 days ago) @ xeno6696
Matt/xeno: "So to me, this means that the solution is going to have to be one of human engineering." - More likely War, Pestilence and Famine. That's the only way I can see of the human population coming under control.
--
GPJ
A new view of mass extinctions...
by David Turell , Saturday, July 04, 2009, 18:32 (5619 days ago) @ George Jelliss
Matt/xeno: "So to me, this means that the solution is going to have to be one of human engineering." > More likely War, Pestilence and Famine. That's the only way I can see of the human population coming under control. - Population experts think we will plateau off aat 10-11 billion, based on the dropping birth rate in advanced countries. The answer then is to bring up everyone to our first world level, if that can be done. It means junking a useless UN and forging a different organization without the graft and mismanagement.
A new view of mass extinctions...
by xeno6696 , Sonoran Desert, Saturday, July 04, 2009, 19:44 (5619 days ago) @ David Turell
Matt/xeno: "So to me, this means that the solution is going to have to be one of human engineering." > > > More likely War, Pestilence and Famine. That's the only way I can see of the human population coming under control. > > Population experts think we will plateau off aat 10-11 billion, based on the dropping birth rate in advanced countries. The answer then is to bring up everyone to our first world level, if that can be done. It means junking a useless UN and forging a different organization without the graft and mismanagement. - Population experts haven't agreed on that since... whoever the Brit was that predicted that we would run out of food back in the 18th century. I've read as high as 19B. - As for the UN, the *only* way that would happen, is if governments agreed to give up sovereignty to whatever replaced the UN. What makes the UN ineffectual is that it can't enforce anything. I see no country allowing such a beast to exist. - EDITED - I advocate dictatorships, ala Roman Republic days.
A new view of mass extinctions...
by xeno6696 , Sonoran Desert, Saturday, July 04, 2009, 19:39 (5619 days ago) @ George Jelliss
Matt/xeno: "So to me, this means that the solution is going to have to be one of human engineering." > > More likely War, Pestilence and Famine. That's the only way I can see of the human population coming under control. - Wow... and I thought I was cynical! lol
A new view of mass extinctions...the Permian
by David Turell , Monday, January 24, 2011, 16:34 (5050 days ago) @ xeno6696
New discoveries point to massive volcanic activity as the major cause of the Permian extinction, with 95% of sea life and 70% of land life killed off 250 million years ago.-http://www.physorg.com/news/2011-01-gun-world-biggest-extinction.html
A new view of mass extinctions: recovery time meaning
by David Turell , Saturday, April 13, 2019, 21:26 (2049 days ago) @ David Turell
A new study of recovery time after the mass extinction of dinosaurs reaches new conclusions about the role of evolution:
https://www.sciencedaily.com/releases/2019/04/190408114252.htm
"The study.... looks at how life recovered after Earth's most recent mass extinction, which snuffed out most dinosaurs 66 million years ago. The asteroid impact that triggered the extinction is the only event in Earth's history that brought about global change faster than present-day climate change, so the authors said the study could offer important insight on recovery from ongoing, human-caused extinction events.
"The idea that evolution -- specifically, how long it takes surviving species to evolve traits that help them fill open ecological niches or create new ones -- could be behind the extinction recovery speed limit is a theory proposed 20 years ago. This study is the first to find evidence for it in the fossil record, the researchers said.
"The team tracked recovery over time using fossils from a type of plankton called foraminifera, or forams. The researchers compared foram diversity with their physical complexity. They found that total complexity recovered before the number of species -- a finding that suggests that a certain level of ecological complexity is needed before diversification can take off.
In other words, mass extinctions wipe out a storehouse of evolutionary innovations from eons past. The speed limit is related to the time it takes to build up a new inventory of traits that can produce new species at a rate comparable to before the extinction event.
"Lead author Christopher Lowery, a research associate at the University of Texas Institute for Geophysics (UTIG), said that the close association of foram complexity with the recovery speed limit points to evolution as the speed control.
"'We see this in our study, but the implication should be that these same processes would be active in all other extinctions," Lowery said. "I think this is the likely explanation for the speed limit of recovery for everything."
***
"The researchers were inspired to look into the link between recovery and evolution because of earlier research that found recovery took millions of years despite many areas being habitable soon after Earth's most recent mass extinction. This suggested a control factor other than the environment alone.
"They found that although foram diversity as a whole was decimated by the asteroid, the species that survived bounced back quickly to refill available niches. However, after this initial recovery, further spikes in species diversity had to wait for the evolution of new traits. As the speed limit would predict, 10 million years after extinction, the overall diversity of forams was nearly back to levels observed before the extinction event. Foram fossils are prolific in ocean sediments around the world, allowing the researchers to closely track species diversity without any large gaps in time."
Comment: There are several related issues that are impacted by this observation. It tells us nothing about the timing of the Cambrian explosion and the huge gap of non-diversification before it. It also raises the issue of so-called 'junk' DNA in which the Darwinists claim the junk is DNA which gets left in place as useless as evolution moves forward to more complexity. This study would seem to imply that the junk is left behind after extinctions as new diversity takes over in the newly formed DNA in new organisms. Mammals certainly would not carry dino DNA. It would be interesting to determine how much junk DNA from dinos is in the current flock of birds.