Extinction events

[Ingwe]

[edit: This thread has been split off the Global Warming thread - Eärniel]

I just think that it shouldn't be so much of an issue of right and left, conservative and liberal, and how much money is up for grabs. Either way, there's a lot of propaganda. It's more about acceptance: there's certainly something going on. Most of us don't know what it is because most of us aren't scientists. All we can tell is what we read about on the net or the newspapers or see on TV or listen to on the radio. But we can see the effects of it. Early springs hit certain areas of the world, and there are noticeable changes every year for some people. I accept that there's an Earth-bound and Solar-bound cause to the recent warming, but that there's also a man-made cause to it as well. Whatever some politician is saying isn't about trying to save the planet, it's usually more about money...isn't that a surprise?

Methane goes up in the atmosphere from industry as well. It is more of a greenhouse gas than CO2. It is one of the elements that caused the Permian-Triassic extinction event. If you'll remember, that killed some 92 to 95% of the life on this planet. As long ago as that may have been, we're sort of over-due for an extinction event. Many think it'll be an asteroid. Some think a gamma ray burst will do it. And still, there are others on the opposite side who think that global warming will wipe us all out very quickly. No...it's a slow-killer. The world 100 years from now will be much different than the one we currently live in - no matter how the deck is played. It might be different in a good way, should the world accept that global warming is actually happening and do something to at least lessen it...or it could be in very much a bad way - where half or more of the Earth's life has slowly (for human standards) but quickly (in geological standards) disappeared. Some areas will be sweltering jungles that were once temperate areas. Great Britain may have climates similar to that of the Mediterranean by just 20 or 30 years from now. I'm not going to be a doom-sayer and state that this is truly what will happen, but it's a lot more likely than the 2012 or 2063 doomsday predictions. Cities will flood over, though. That part is probably true.

We just all have to do our own part in reducing the effects. Industry is necessary today, but it needs to be slowly converted over to clean and safe industry. I hope the people overall will make the right choices, but the year 2110 will definitely be somewhere between 100% totally screwed and a 100% utopia. I'm guessing it will be close to somewhere around...25 or 50% totally screwed, though. And that is not good.

[Earniel]

Originally Posted by Ingwe

As long ago as that may have been, we're sort of over-due for an extinction event.

Over-due? We're already in an extinction event right now, why would you need another one!?

[inked]

Gee, what extinction event are we in RIGHT NOW?

[Earniel]

*shrugs* If you're going to be like that I'm not going to bother. Things like the amphibian decline, white-nose-syndrome, shark decimation, habitat loss and degradation, bush meat trade, ivory smuggle, the very, very long IUCN red list of threathened and endangered species, etc... aren't going away just because you don't think they matter.

[inked]

I did not know these were labelled as extinction event(s). Your list does not approach that of the K-T boundary extinction(s).

A wee bit over dramatic, perhaps?

[GrayMouser]

Her's one of the thousand references out there.

http://www.sciencedaily.com/releases...0109074801.htm

The most conservative estimate -very, very conservative, and almost certainly a drastic underestimate- is that current extinction rates are about 100x the background rate (the level of species extinction whch occurs under normal conditions)

Some estimates put it at 1000x times the background rate (as we learn of more species, we learn how many moreare being wiped out
Try Googling " Holocene Extinction Event" .

Though I'm sure all those biologists are flat-out lying in order to get research grants- just like the climatologists.

BTW, funny we haven't heard anything after all those 'climategate' accusations were shown to be a crock- though of course all the investigations that cleared those involved must have been part of the conspiracy, too.

[Earniel]

Originally Posted by inked

I did not know these were labelled as extinction event(s). Your list does not approach that of the K-T boundary extinction(s).

A wee bit over dramatic, perhaps?

No, of course these aren't labelled as extinction events seperately, but they're all attributing to one. An extinction event does not have to have a single cause, it is merely a term for a period where the number of species decline significantly. Not all extinctions have to be as dramatic as the K-T extinction to be labelled an extinction event.

[Count Comfect]

Eärniel is right; an extinction event is not an event in the sense of a single action that happens in a single moment or from a single cause (like a meteor striking the earth, say) but rather a term used to describe a small (on a geological scale) period in which species extinction rates climb dramatically relative to the background rate, for whatever reason.

[inked]

Well, given the massive observational data on extinction events by homo sapiens, not recorded very well until recently in terms of human conceptualizations, over the millions of years sapientially inclined species have been proliferating, not to mention the near-extinction event of only about 2000 individuals having been the bottleneck of human genomics, I do have a bit of a problem with extinction events, near extinction events, extinction rates,and the whole rather muddled stuff promulgated as "scientifically established".

But I only have an estimated 6 billion reasons to doubt near-extinction events as necessarily proof of the postulate.

Then again, there is the dodo. Pardon, then again there WAS the dodo, and the Carolina Parakeet.

[Earniel]

Sorry, I don't think I got any of that. Try using smaller words. Or maybe just plain Dutch.

In any case if everything you come up with when thinking of extinction is the dodo - extinction icon though it is- I think your ideas on modern-day extinction are maybe a little out-dated.

Paraphrased from the IUCN website (concerning amphibians specifically since I have a special interest in them):

Unfortunately, there is strong evidence that the pace of extinctions is increasing. Of the 38 known extinctions, 9 have occurred since 1980, including such species as the golden toad (Bufo periglenes) of Monteverde, Costa Rica. Among those amphibians regarded as "possibly extinct", (120 species assessed as such) most have disappeared and not been seen since 1980.

And keep in mind that a third of the 6000+ assessed species is classed as globally threatened or extinct and for another fourth there is insufficient data to assess their status. All in all not a pretty picture.

[GrayMouser]

It's sometimes difficult to hazard a guess as to what inked is thinking, but I'd say he's somehow interpreting "Extincion Event" as something that is only relevant if it affects humans.

[inked]

I grasp that some labelled and known species are alleged to exist no more. This is a natural phenomenon, too. So how does one differentiate between an extinction event and the loss of species which is wholly natural?

Darwin claimed that natural selection would result in the loss of lesser fit species, did he not?

But, how does this concept compare to the idea that there are tens of thousands of species not yet identified and great biodiversity yet to be discovered?

Does the discovery of previously unknown species of plants/animals/insects/etc replace the disappearing, or are we actually longing for a static reality which has never existed according to theory?

[Earniel]

Originally Posted by GrayMouser

It's sometimes difficult to hazard a guess as to what inked is thinking, but I'd say he's somehow interpreting "Extincion Event" as something that is only relevant if it affects humans.

Is that true, Inked? Your comment of 'nearly 6 billion reasons' does seem to point in that direction. If so, you appear to have an erroneous idea of the concept of extinction events and its significance. But I suppose that would explain your questions.

Originally Posted by inked

I grasp that some labelled and known species are alleged to exist no more. This is a natural phenomenon, too. So how does one differentiate between an extinction event and the loss of species which is wholly natural?

No one has ever denied extinction cannot be a natural phenomenon. Extinction is to a species what death is to an individual. The fact that both can occur naturally or articifially has no bearing on the concept or reality of extinction events. Have you not read Graymouser's and Count Comfect's previous posts? You would have found your answer there.

[Count Comfect]

An extension of Earniel's analogy might perhaps be helpful here. People die; this is natural. But if suddenly five times as many people were dying in a particular town every year than usually die in a year, we'd probably say something was wrong, and try to figure out what and how to deal with it, even though death is a natural phenomenon.

[inked]

Well, natural deaths are natural and natural extinctions are natural. What I am trying to understand is why Earniel applies the term extinction event to the current losses of species alleged to be occurring. It seems overly dramatic. The claim makes a great sound byte, I agree, but do we actually know that the rate of disappearance equates to prior genuine extinction events understood geologically or are we hyping natural occurences as evidence for our pet theories of human causation?

And, if species are disappearing, is this offset by the discovery of new species?

Or are we taking our propaganda seriously and alleging that we are humanly destroying x # of species before we can discover them and therefore there is an extinction event?

What x over what y constitutes an extinction event in the sense that some global extinction event is taking place?

[Count Comfect]

As I believe has been explained, we are comparing the generally understood background rate of extinction over geological and historical time (which there is a large body of literature devoted to studying) and comparing it to the rate of known extinction now - which is substantially higher, which as discussed is practically the definition of an extinction event. Again, "event" is perhaps a misleading term - but it's definitely a period in which extinction rates have gone up markedly. And we're not just doing this by estimating that "we are humanly destroying x # of species before we can discover them;" we're looking at species we already know about and seeing them go extinct. Earniel gave you some fine examples of those.

Furthermore, your question about extinction being "offset by the discovery of new species" misses the point somewhat. We aren't discovering new species in the sense that currently known species are speciating into new varieties; we're discovering new species in the sense that they existed before but we hadn't found them (for example, we've only explored some absurdly small percentage of the seafloor, so we discover new species there practically every time we go down). So there is no "offset," because there isn't an actual increase in the number of species that exist. Rather, we are simultaneously seeing a) our knowledge of the world increase, so that we know of more species and b) an alarmingly large number of those known species go extinct.

[Jonathan]

Originally Posted by inked

What I am trying to understand is why Earniel applies the term extinction event to the current losses of species alleged to be occurring.

Well, when rainforests are cut down rapidly and thus killing off species at an alarming rate - many have chosen to call it extinction. It's an accepted term and I'm surprised that inked is surprised by it.

If you google "extinction" + "rainforest" you'll get some interesting hit, such as:
"The average rate of extinction in the rainforest is 140 [species] per day". Or 35, according to another site. Mind you, this is the number of species extinct, not just affected. That number is much greater.

Savetherainforest.org offers the following info:

. . . "man has recently increased nature’s "normal" extinction rate by 10,000%. Most of this increase is taking place in the rainforests."
. . . "by conservative estimates, 9,000 species are going extinct each year, most of them from the rainforests."
. . . "we are presently experiencing the largest mass extinction since the demise of the dinosaurs 65 million years ago; only this time it’s occurring at a much faster rate."

[Earniel]

Originally Posted by inked

Well, natural deaths are natural and natural extinctions are natural. What I am trying to understand is why Earniel applies the term extinction event to the current losses of species alleged to be occurring. It seems overly dramatic.

Again, at the danger of repeating myself, it's the rate of extinctions in an event that is the key, not the cause. Extinction event may be a dramatic word (well, two words...), yes, but it still applies. But maybe it's just better that I link to these: extinction event and background extinction rate.

The claim makes a great sound byte, I agree, but do we actually know that the rate of disappearance equates to prior genuine extinction events understood geologically or are we hyping natural occurences as evidence for our pet theories of human causation?

So, if I get it right, you claim that since this extinction event does not have the high numbers of extinctions seen in previous extinction events that can be found it in the geological record, we can't possibly be in an extinction event. That's not quite how it works. An earthquake at 5 on the Richter magnitude scale is still as much an earthquake as one of 10.

But I think I have found in this quote what appears to be the heart of your reluctance to take extinction events seriously. You seem to think that extinction events are just environmental propaganda and exist merely to fuel a specific agenda. But whether humans are involved doesn't make it an extinction event. After all, most of the known extinction events happened millennia before humanity was even a fact. And while technically humanity is responsible for a good deal of the modern-era extinctions, both direct (e.g. extermination of the thylacine) or indirect (e.g. spreading chytrid fungus that has driven several amphibians to extinction and the brink thereof), again, the cause(s) isn't a factor in calling an extinction event an extinction event.

I am going to split off this thread, since we've gotten a little bit off track.

[EllethValatari]

I'm going to annoy everyone and take the philosophical approach to this issue, which ironically is the simplest approach. The extinction of an animal is a universal negative. Basically, if a scientist states that an animal is extinct, he is saying that "No (insert animal) is living on this earth." However, this fact cannot be proven unless someone were able to observe every inch of this earth at the same time, and thus deem the above statement correct. Debate proven unprofitable

[Tessar]

Originally Posted by EllethValatari

The extinction of an animal is a universal negative.

Yes and no. One definition of extinction is "the act or process of becoming extinct; a coming to an end or dying out." Meaning that a species need not be entirely gone to be in the midst of extinction. Hence why scientists and researchers will often say, "Thought to be extinct," because, as you said, there is really no way to prove that a species is 100% gone from the world.

Debate proven unprofitable

This is not really a true statement.

The discussion at hand involves several topics, including the causes of extinction ("are we causing it?"), what is defined as an extinction event, and what is a natural rate of species decline vs. what is being caused by outside forces.

You are simply stating that you don't think it's possible to call a species extinct, which in truth is not really the topic being debated. The topic being debated is about the event of extinction.

Another problem is that by saying such a debate is unprofitable you are basically saying, "Well we can't prove it 100% so we shouldn't bother." That's like saying, "I'm not sure that my dishwasher is getting every scrap of harmful bacteria off of my plate, so I wont bother washing it." There is a balance to be reached between "what's too much concern?" and "what is too little effort?" and that is part of what inspires this kind of debate. To just say that because we're not all scientists we shouldn't talk about it, or because even scientists can't prove it for sure, is not conducive to progress or balance.