Newly Discovered Sixth Extinction Rivals That of the Dinosaurs

sciencehabit writes Earth has seen its share of catastrophes, the worst being the 'big five' mass extinctions scientists traditionally talk about. Now, paleontologists are arguing that a sixth extinction, 260 million years ago, at the end of a geological age called the Capitanian, deserves to be a member of the exclusive club. In a new study, they offer evidence for a massive die-off in shallow, cool waters in what is now Norway. That finding, combined with previous evidence of extinctions in tropical waters, means that the Capitanian was a global catastrophe.

Comments

The real extinction

[Anonymous Coward]

The real sixth extinction is what man is doing to the planet right now. Species are going extinct at way higher than background rates, and we are largely to blame.

Re:The real extinction

[Anonymous Coward]

No.

There is a great lecture by Dr. Albert A. Bartlett on Youtube about growth.
In the second part around the 6 minute mark he presents a list of options.
I would say that he is reasonable pragmatic about it. Either we pick a way to limit population growth or nature selects a way for us.
In the long run it doesn't really matter what option we go for but there seem to be a short time benefit of choosing a less painful population reduction method.
I think the one child per family method is pretty good. It's not very fast, but it keeps population down while still allowing people to get children. Another benefit is that it is far less violent than many of the other options.
If you want to go all out you can always join The Voluntary Human Extinction Movement They try to achieve human extinction by encouraging people to not have children at all.

Re:The real extinction

[ColdWetDog]

For those of the geological persuasion, 50 000 years is certainly 'right now'.

Re:The real extinction

[oodaloop]

The evidence of man's mass extinction is so vast and well-documented, that I'm going to go ahead and say you haven't done a lick of research. Saying there's no evidence for the Holocene Extinction is tantamount to saying we aren't changing the climate or evolution is not happening. You're either lying or illiterate. Or both.

Re:The real extinction

[buchner.johannes]

Try these?

• Firestone RB, West A, Kennett JP et al. (October 2007). "Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling". Proceedings of the National Academy of Sciences of the United States of America 104 (41): 16016–21. Bibcode:2007PNAS..10416016F. doi:10.1073/pnas.0706977104. PMC 1994902. PMID 17901202.
• Loarie, Scott R.; Duffy, Philip B.; Hamilton, Healy; Asner, Gregory P.; Field, Christopher B.; Ackerly, David D. (2009). "The velocity of climate change". Nature 462 (7276): 1052–1055. Bibcode:2009Natur.462.1052L. doi:10.1038/nature08649. PMID 20033047.
• Steadman, D. W. (1995). "Prehistoric extinctions of Pacific island birds: biodiversity meets zooarchaeology". Science 267 (5201): 1123–1131. Bibcode:1995Sci...267.1123S. doi:10.1126/science.267.5201.1123.
• Steadman, D. W.; Martin, P. S. (2003). "The late Quaternary extinction and future resurrection of birds on Pacific islands". Earth Science Reviews 61 (1–2): 133–147. Bibcode:2003ESRv...61..133S. doi:10.1016/S0012-8252(02)00116-2.

and

• S.L. Pimm, G.J. Russell, J.L. Gittleman and T.M. Brooks, The Future of Biodiversity, Science 269: 347–350 (1995)
  Doughty, C. E., A. Wolf, and C. B. Field (2010), Biophysical feedbacks between the Pleistocene megafauna extinction and climate: The first humaninduced global warming?,Geophys. Res. Lett., 37, L15703, doi:10.1029/2010GL043985
• Pitulko, V. V., P. A. Nikolsky, E. Y. Girya, A. E. Basilyan, V. E. Tumskoy, S. A. Koulakov, S. N. Astakhov, E. Y. Pavlova, and M. A. Anisimov (2004), The Yana RHS site: Humans in the Arctic before the Last Glacial Maximum, Science, 303(5654), 52–56, doi:10.1126/science.1085219
• Barnosky, Anthony D.; Matzke, Nicholas; Tomiya, Susumu; Wogan, Guinevere O. U.; Swartz, Brian; Quental, Tiago B.; Marshall, Charles; McGuire, Jenny L.; Lindsey, Emily L.; Maguire, Kaitlin C.; Mersey, Ben; Ferrer, Elizabeth A. (3 March 2011). "Has the Earth’s sixth mass extinction already arrived?". Nature 471 (7336): 51–57. Bibcode:2011Natur.471...51B. doi:10.1038/nature09678.
• Zalasiewicz, Jan; Williams, Mark; Smith, Alan; Barry, Tiffany L.; Coe, Angela L.; Bown, Paul R.; Brenchley, Patrick; Cantrill, David; Gale, Andrew; Gibbard, Philip; Gregory, F. John; Hounslow, Mark W.; Kerr, Andrew C.; Pearson, Paul; Knox, Robert; Powell, John; Waters, Colin; Marshall, John; Oates, Michael; Rawson, Peter; Stone, Philip (2008). "Are we now living in the Anthropocene". GSA Today 18 (2): 4. doi:10.1130/GSAT01802A.1.
• Vitousek, P. M.; Mooney, H. A.; Lubchenco, J.; Melillo, J. M. (1997). "Human Domination of Earth's Ecosystems". Science 277 (5325): 494–499. doi:10.1126/science.277.5325.494.
• Wooldridge, S. A. (9 June 2008). "Mass extinctions past and present: a unifying hypothesis". Biogeosciences Discuss (Copernicus) 5 (3): 2401–2423. doi:10.5194/bgd-5-2401-2008.
• Jackson, J. B. C. (Aug 2008). "Colloquium paper: ecological extinction and evolution in the brave new ocean" (Free full text). Proceedings of the National Academy of Sciences of the United States of America 105 (Suppl 1): 11458–11465. Bibcode:2008PNAS..10511458J. doi:10.1073/pnas.0802812105. ISSN 0027-8424. PMC 2556419. PMID 18695220. edit
• Elewa, Ashraf M. T. "14. Current mass extinction". In Elewa, Ashraf M. T. Mass Extinction. pp. 191–194. doi:10.1007/978-3-540-75916-4_14.
  Mason, Betsy (10 December 2003). "Man has been changing climate for 8,000 years". Nature. doi:10.1038/news031208-7.
  MacPhee and Marx published their hyperdisease hypothesis in 1997. "The 40,000-year plague: Humans, hyperdisease, and first-contact extinctions." In S. M. Goodman and B. D. Patterson (eds), Natural Change and Human Impact in Madagascar, pp. 169–217, Smithsonian Institution Press: Washington DC.
• Lyons, S. Kathleen; Smith, Felisa A.; Wagner, Peter J.; White, Ethan P.; Brown, James H. (2004). "

Re:The real extinction

[radl33t]

go red team! http://www.sciencedaily.com/re...

Re:The real extinction

[BarbaraHudson]

The problem is that (and sci-fi stories have predicted this for decades) if the people who voluntarily cut back on their breeding aren't somehow matched (probably through compulsory sterilization) with breeders who think it's their right ti have up to a dozen kids or more, then eventually we're back to almost everyone being a selfish breeder.

Re:The real extinction

[khallow]

He's not saying that the extinctions aren 't happening. He's saying that we don't know that they're comparable to the big extinctions of the past. It's worth remembering here that there is a huge problem with comparing modern world extinctions with extinctions in the geological past. First, it is vastly easier to see and catalog species today than in the past where fossilization is an extremely rare event. We can't know what didn't get fossilized.

But creatures which weren't easy to drive extinct, due to numbers, longevity of the species, or widespread habitat, would also be more likely to leave fossils. So we also have that the fossils of the geological past come from species which are more likely to not be threatened by extinction than the usual species today.

Third, species have different meanings in modern and geological terms. Today, we can classify species based on subtle distinctions like behavior, coloration, habitat, and most important, DNA which usually are impossible to determine from fossil records. Fossil species on the other hand, are determined by rather crude morphology traits which can be fossilized. A fossil species is a much bigger grouping than a modern species.

So when you combine all these aspects, you get that extinction of a fossil species is a much bigger deal just on its own than extinction of a modern species and may represent in some cases the extinction of dozens of modern species.

I think a better measure here is extinction at the genus level. Genuses are more likely to have fossil records and we can speak of the relative decline of the number of genuses in a proposed extinction event.

When you do that, I don't think there is a serious comparison at the present between human-caused extinction and geological extinction events. I suspect most genus-level extinctions would be in large terrestrial animals, amphibians, and any genus of organisms particularly susceptible to local habitat destruction. You don't have large scale declines in the number of all land and sea genus-level organisms (which can be fossilized) as are present during major extinction events of the past.

Re:The real extinction

[sudon't]

Well, that would make the Holocene extinction number seven.

And the seventh mas extinction?

[MichaelSmith]

Must be now.

Re:And the seventh mas extinction?

[Anonymous Coward]

http://en.wikipedia.org/wiki/H...

The Holocene extinction, sometimes called the Sixth Extinction, is a name proposed to describe the currently ongoing extinction event of species during the present Holocene epoch (since around 10,000 BCE) mainly due to human activity.

The large number of extinctions span numerous families of plants and animals including mammals, birds, amphibians, reptiles and arthropods. Although 875 extinctions occurring between 1500 and 2009 have been documented by the International Union for Conservation of Nature and Natural Resources, the vast majority are undocumented. According to the species-area theory and based on upper-bound estimating, the present rate of extinction may be up to 140,000 species per year.

Re:Coincidence?

[ColdWetDog]

It happened just after they developed systemd.

The proposed sixth extinction event happened some 250 million years ago. I don't think the Unix epoch covers that range of time.

Re:Humans are the gross, worst spieces ever

[Somebody Is Using My]

[Humans are] the worst disgusting and gross, leave their trash everywhere. They think all history was made in order for their own creation. They pollute everywhere they figure out how to get to.

Do not mistake the ineffectiveness of other animals to be "care" for their environment. A beaver will happily defoliate acres of land. Cats can depopulate entire species of birds, given the chance. Rabbits will breed far beyond the capacity of their environment to support their numbers. All of them will "pollute" as readily as man, leaving their waste wherever it may drop and not taking particular care to "clean up" after themselves when they are done using a burrow or nest. Certainly, they show no evidence of caring about other species; other animals are prey to be fed upon, or predator to be fled from, or other to be ignored but never a concern beyond that.

Humans aren't perfect, to be sure, but our problems are largely due to own success. Though we would believe ourselves somehow superior to the "lesser animals" with which we share the world, we are still moved by the same base impulses of our distant cousins. However, our cleverness with tools and our extreme adaptability means that we are more resistant to environmental repercussions with which the system uses to self-correct the actions of its more boisterous inhabitants. A wolf-pack that eats all the deer in its territory is likely to starve next winter, but Men will just move to a new territory or import food from its neighbors, and thus the genes of the "over-eaters" are preserved rather than culled. Alas, now that our territory encompasses the entire world it may require a worldwide disaster to rehabilitate Man.

But then again, maybe not. Because we are learning - however slowly it may seem - that not only are our resources not unlimited, but also that the Earth is a vast and interlocked system which we share with all the other species on the planet. This very concept of environmentalism is fairly new - a few hundred years at most and truly popular only for the last two or three generations - and prior to this Men took little concern to their depredations because they always thought there would be an endless supply so long as they moved to the next horizon. Now, we are reconsidering our actions - acting against the very instructions of our genetic make-up - working to preserve what we have. While it is not entirely without self-interest, nor is it entirely selfish; we preserve other species for no other reason than a belief that they have as much a right to exist on this planet as we do. That is more than any other species on Earth has done.

Our impact on this planet has been devastating, matched perhaps only by the impact of micro-organisms or the insect kingdom. But these mistakes are only because we follow our genetic predisposition to breed to capacity and do not believe for a moment that any other species on this planet would do any different. Certainly we should use our intellects to curb our innate predilections but neither should we entirely condemn ourselves.

Re:Global?

[Anonymous Coward]

Prehistoric Norway was much larger than it's modern counterpart

Once the seas teamed with huge Norways, but that was before over-norwaling