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Comments 1 to 50 out of 87:

1. Tom Dayton at 10:20 AM on 23 January, 2012
   Another organization that tries to educate about climate change is the U.S 's National Earth Sciences Teachers Association. Their executive director Dr. Roberta Johnson yesterday was on NPR radio's This American Life in episode 424, Kid Politics, Act Two. Host Ira Glass had her in one studio and a young teenager in another studio. He had the Dr. give her best arguments and the teenager respond with how convincing it was. The teen was thoroughly unconvinced. The teen's bottom line was that she might be convinced if she saw both sides of the argument laid out side by side. Hey! That's what Skeptical Science does! Will somebody please tweet or comment on Facebook to that radio program? I don't tweet and I rarely Facebook. Also it would be good for somebody to ensure the Dr. knows that SkS provides what the teen was asking for.
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2. tmac57 at 10:55 AM on 23 January, 2012
   Eugenie Scott was recently featured on 4 of the podcasts that I regularly listen to, discussing the NCSE's new project.These podcasts are all done by real Skeptic organizations,not the fake ones: The Skeptics Guide to the Universe episode #340 http://www.theskepticsguide.org/ Rationally Speaking RS49 http://www.rationallyspeakingpodcast.org/show/rs49-eugenie-c-scott-on-denialism-of-climate-change-and-evol.html Skeptically Speaking #147 http://skepticallyspeaking.ca/episodes/147-science-and-politics Point of Inquiry http://www.pointofinquiry.org/eugenie_scott_defending_climate_education/
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3. Bernard J. at 12:23 PM on 23 January, 2012
   Tom Dayton at #1. That is indeed a worrying recount. What that radio exercise shows is how a pseudoscientifically-influenced teen resists understanding proper science when it is explained to her, rather than how the science is, in and of itself, unconvincing. Sadly, many in the audience would not understand the very significant difference between the two situations. Of course, knowing that youth conditioned to denialism are not receptive to rational explanation is a useful thing, so it's not a completely wasted exercise. However, what it tells us is that a better forum than a radio stunt is required for delivery of real science to ideologically-indoctrinated denialist kids. It doesn't tell us that there is any problem with the science itself, no matter how much that will be the impression left in the minds of many who listened. I hope that the efforts of the National Center for Science Education go a long way to reversing this fundamentalist conservative resistance to rationalism.
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4. Tom Dayton at 13:31 PM on 23 January, 2012
   I emailed to Dr. Johnson a heads-up about Skeptical Science's Arguments pages. Not going to tweet or Facebook to the radio program, so it would be nice if somebody else did.
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5. KR at 14:06 PM on 23 January, 2012
   Eugene Scott is already aware of SkS (NPR link), and the NCSE is currently looking at climate change as an ideological issue in the classroom. I'm quite astounded that the "no government regulation" folks are more than willing to legislate facts in the same way that intelligent design/creationism activists are. And quite disappointed. Apparently well loved talking points triumph over ideology for some...
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6. muoncounter at 15:33 PM on 23 January, 2012
   Aargh! Their link to SkS used to be above their RealClimate link.
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7. apiratelooksat50 at 15:36 PM on 23 January, 2012
   If I'm using Climate Change 101 as a resource for teaching, and I tell my students that climate change has led to the "extinction of plant and animal species", and they ask me to list the species - what do I say?
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8. KR at 15:45 PM on 23 January, 2012
   apiratelooksat50 - I would suggest simply looking at something like this, and doing the requisite reading.
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9. Chris G at 15:49 PM on 23 January, 2012
   Pirate, I'm thinking you should also clarify whether you mean climate change within the last 100 years, or climate change in paleohistory.
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10. Rob Painting at 15:54 PM on 23 January, 2012
    Wasn't there a golden frog is Central America that went extinct because it became too warm? I know a truckload of lizards are disappearing from the tropics quicksmart as a result global warming, and some frog species are disappearing as a result of warming spreading bacteria into populations with no natural resistance. Actually the extinction of species in the tropics is alarming - there's no other apt description for it. The trouble is humans extinguish plants and animals in so many different ways, not only by making it too warm. I've a stackload of papers of extinctions and global warming, but have yet to get to writing about them. One day......
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11. Rob Painting at 15:58 PM on 23 January, 2012
    Pirate - .....and I tell my students that climate change has led to the "extinction of plant and animal species", and they ask me to list the species - what do I say? What about? "I haven't actually bothered to research the topic." Nothing like a bit of honesty.
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12. apiratelooksat50 at 16:20 PM on 23 January, 2012
    KR at 8 I previously did what you suggested and could not find a list of species. Your search turned up either past extinctions or projections/risks. Chris G at 9 I mean currently just like in Climate Change 101. Please follow the link to the NCSE site and read the first bullet under Climate Change 101.
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13. KR at 16:29 PM on 23 January, 2012
    apiratelooksat50- For a more specific example, you might Google "amphibian extinction climate change". But more seriously, look at the historic record - how do extinction numbers vary with changes in the environment? Permian–Triassic extinction event? PETM? Younger Dryas impact? And if you don't recognize that fast changes in the environment relate rather directly to extinction rates, you're not doing your homework. And - you are not doing a great job of teaching your students how to look at the data.
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14. apiratelooksat50 at 16:34 PM on 23 January, 2012
    Rob at 11 and 12 The chytrid fungus is responsible for the demise of many amphibians worldwide including the Golden Frog. Don't quote me on this, but I don't believe any species have gone extinct from it. Oddly enough the fungus was spread by researchers investigating population declines. What is the "warming spreading bacteria" you're referring to? What species of frogs are gone from that bacteria, and what are the lizard species disappearing due to global warming? Nothing like a bit of honesty, eh?
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15. apiratelooksat50 at 16:40 PM on 23 January, 2012
    KR at 13 I'm referring to the NCSE website statement. Give me a list of modern species that are extinct due to climate change. I'm not saying climate change is not a problem. Rapid environmental changes are stressors on organisms. That's a basic fact that I teach.
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16. KR at 17:10 PM on 23 January, 2012
    apiratelooksat50 - Back to the topic at hand: Are you claiming (due to your inability to identify specific species at risk/extinct due to climate change, despite numerous examples of amphibian extinction, high altitude flora, polar bears, etc) that climate change is not worth teaching in the classroom? Or is there some other point to your side-track discussion? Because this thread is about teaching climate change and the science behind it. And you are running well off topic.
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17. Kevin C at 18:25 PM on 23 January, 2012
    Actually, this discussion has some relevance NCSE since it provides an interesting case study in one of the techniques the disinformation movement uses to manufacture doubt. I guess the form would is: - Raise a long term impact and demand short term evidence of the impact (a special-case of hiding the signal in the noise). - Attempts to point out the above would normally be greeted with the response 'why are you trying to avoid the issue?' (I know nothing about extinctions, and they are indeed off topic. But I wonder if there is mileage in compiling a list of distraction strategies in a similar form to the one above?)
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18. OPatrick at 18:36 PM on 23 January, 2012
    Whilst I'm loathe to prolong the piratical diversion I'll just briefly suggest that a sensible response to your students would be to explain the complexity of the impacts we are having and therefore the inappropriateness of ascribing single causes to extinctions in individual cases, whilst emphasising the importance of understanding trends in an historical context. And perhaps a good resource would be this, from the Royal Society: http://rstb.royalsocietypublishing.org/content/365/1558/3593.full
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19. Bernard J. at 19:04 PM on 23 January, 2012

    Don't quote me on this, but I don't believe any species have gone extinct from it. Oddly enough the fungus was spread by researchers investigating population declines.

    Sorry, but I have to quote you on this, as off-topic as it is. There are a number of Australian anuran species whose extinctions are attributable to chytrid, even though the fungus's spread and virulence was such that it's really only possible to establish a post hoc, prima facie case. A couple of species of Taudactylus and both Rheobatrachus are almost certainly victims of chytrid, and I'd peg at least half of the recently extinct Litoria to the fungus as well. And this is apart from the worrying number of extant but endangered Australian species directly suffering from the impact of chytrid. The fungus works fast, and spreads inexorably. I've watched seemingly healthy Litoria citropa fall dead from streamside vegetation, having suddeningly succumbed from the fungus. So it's wrong to say that the fungus is not an extinction agent. It's also wrong to say that the fungus was spread by investigators studying declines. I suspect that it certainly was spread - in part - by investigators studying the frogs, but by the time that they were seriously investigating the disease-related declines there were decontamination protocols in place. The initial spreading probably occurred when the species were being studied in order to understand their autecologies, and in the case of Rheobatrachus, the genus's remarkable brooding physiology. This response to apiratelooksat50 might be pedantry, but it's important to nip the heresay in the bud. Here endeth the lesson.
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20. Rob Painting at 19:45 PM on 23 January, 2012
    Pirate - "Nothing like a bit of honesty, eh?" Dude, you're not addressing a fake-skeptic. I did tell you I've accumulated a stackload of peer-reviewed papers, there's no "gotcha!" with me I'm afraid. Range retractions and extinction in the face of climate warming - Thomas (2006) states: ".......However, recent papers on butterflies and frogs now show that population-level and species-level extinctions are occurring. The relative lack of previous information about range retractions and extinctions appears to stem, at least partly, from a failure to survey the distributions of species at sufficiently fine resolution to detect declines, and from a failure to attribute such declines to climate change. The new evidence suggests that climate-driven extinctions and range retractions are already widespread" Pirate -"What is the "warming spreading bacteria" you're referring to? What species of frogs are gone from that bacteria" Widespread amphibian extinctions from epidemic disease driven by global warming - Pounds (2006) "As the Earth warms, many species are likely to disappear, often because of changing disease dynamics. Here we show that a recent mass extinction associated with pathogen outbreaks is tied to global warming. Seventeen years ago, in the mountains of Costa Rica, the Monteverde harlequin frog (Atelopus sp.) vanished along with the golden toad (Bufo periglenes). An estimated 67% of the 110 or so species of Atelopus, which are endemic to the American tropics, have met the same fate, and a pathogenic chytrid fungus (Batrachochytrium dendrobatidis) is implicated. Analysing the timing of losses in relation to changes in sea surface and air temperatures, we conclude with 'very high confidence' (> 99%, following the Intergovernmental Panel on Climate Change, IPCC) that large-scale warming is a key factor in the disappearances. We propose that temperatures at many highland localities are shifting towards the growth optimum of Batrachochytrium, thus encouraging outbreaks. With climate change promoting infectious disease and eroding biodiversity, the urgency of reducing greenhouse-gas concentrations is now undeniable." Shucks, the golden toad probably did go extinct as a result of global warming after all. Just like I said. Also, ask your students to research the American Pika (just to keep it relevant to them). That ain't going to be around much longer. And you could also get them to research all the species that went extinct from previous (natural) global warming episodes too. Mind you this would require research, something you don't appear well-versed in.
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21. Rob Painting at 21:39 PM on 23 January, 2012
    Bernard J - wasn't there also some white possums in Queensland that went extinct due to an extreme heatwave? IIRC they were restricted to one particular mountain, and started dropping dead in their thousands when it got too hot. Then again I could be mixing up several papers in my jumbled collection.
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22. Tom Dayton at 23:46 PM on 23 January, 2012
    Dr. Johnson responded to my email about the teen's reaction to Dr. Johnson's arguments, and my suggestion that Skeptical Science's Arguments pages fit the teen's bottom line request for convincing evidence:

    Hi, Thanks so much for your note.  It doesn't come across in the short version of the interview aired, but I actually had a talk with Ira and Erin for an hour and a half.  I did recommend this website to her as one of the best out there to see the evidence.  When we started the interview, her perspective was "Global warming isn't happening, and the scientists are all on the make". When we ended, she got to "Ok, well maybe it is happening, but I'm not sure why".  To me, that felt like a minor victory - with more time, and a chance for her to investigate quality resources herself, there's a chance she'll get there. I'm really glad I did this interview - learned a lot from it, and have enjoyed getting emails out of the blue from people I don't know, sharing their thoughts.

    Dr. Johnson later wrote regarding Skeptical Science:

    I think very highly of it, and use it when I'm working with teachers.  Are you aware of our work re climate change professional development for teachers?  We also have extensive collections on climate change on the Windows to the Universe website, which gets about 14 million visits annually.  I've thought of being in touch with the Skeptical Science group, but haven't as of yet.

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23. apiratelooksat50 at 02:13 AM on 24 January, 2012
    Actually, my questioning this statement is not off-topic. When I followed the link "Teaching About Climate Change", it leads you back to "Climate Change 101" you get this statement as the very first bullet point: "Is the climate changing right now? Scientists who study the Earth’s climate today and who investigate past climates agree that global temperature has increased rapidly and significantly in the last 150 years. We’re also seeing similarly dramatic changes in other aspects of climate and related effects on ecosystems, including the distribution of rainfall, storm activity, extinction of plant and animal species, and seasonal change." We are actually studying population ecology now and studying extinctions. This topic on SKS is apropos and there is treasure trove of information on the NCSE site that I intend to use. I disagree with the one statement that extinctions from climate change have already occurred "right now". That is why I asked anyone to list just one and it can't be done. My question, per their website posting, does not concern past extinctions or potential future extinctions. The NCSE statement is simply incorrect. Before I go any further with this post - what I teach in class is that climate change is occurring and does have negative implications for the environment. Today we started studying amphibian decline worldwide, and are drilling down on the chytrid fungus. We use a lot of information from Dr. Vance Vredenburg. We also study how science was wrong about frog deformities and mortality for many years. Blame was placed in turn on the coal industry (mercury), farming practices (fertilizer runoff), the ozone hole (UV radiation), and finally global climate change. Hypotheses were tested and discarded until the right culprit was found and now we can act on it. That is the way science works. Now, before anyone gets worked up, the next part I teach is that while climate change is not the cause of the chytrid amphibian issues, it does contribute to it. Drought causes frogs to congregate in moist areas and the fungus spreads more easily. Oddly enough, the fungus prefers cooler temperatures and actually dies at temperatures above 32 degrees C.
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24. CBDunkerson at 02:36 AM on 24 January, 2012
    pirate, setting aside the fact that (contrary to what you say) examples of extinctions linked to climate change have been provided... your characterization of the NCSE statement doesn't seem entirely accurate. The "right now" you keep quoting isn't even from the same sentence as the text about extinction. Parsing the sentence to exclude side clauses we get; 'We are also seeing similarly dramatic changes in extinction of plant and animal species.' The 'also' and 'similarly' refer back to the mention of significant changes over the past 150 years in the prior sentence. Have there been significant changes in extinction over the past 150 years? I'd say yes. Are all of these due to climate change? No, but the text doesn't say they are. It could certainly be taken as implied that climate change is involved in some, but then... even you concede that climate change 'contributed' to extinctions from chytrid. You seem to be choosing to make the NCSE statement 'false' by redefining it to be so. On its own it is a perfectly reasonable and accurate statement.
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25. tmac57 at 03:13 AM on 24 January, 2012
    Pirate-

    I disagree with the one statement that extinctions from climate change have already occurred "right now".

    The NCSE statement is simply incorrect.

    These two sentences tell a lot about your mindset.You aren't saying that you have doubts/questions about whether or not it is true,you are sure that it is not true.Right?
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26. Tristan at 03:36 AM on 24 January, 2012
    Climate Change appears to be increasing the likelihood of extreme weather. Can we attribute any single instance of extreme weather to Climate Change? No. Climate Change loads the dice such that extreme events are more likely. Many of the impacts of Climate Change have the capacity to exert pressure on certain populations of flora and fauna. Does that mean we can look at a given extinction and determine whether it can be attributed to Climate Change or not? It will very rarely be clear cut. We can infer though, that the existence of Climate Change loads the extinction dice as well. Whether or not we can attribute particular extinctions to Climate Change is mostly immaterial.
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27. muoncounter at 04:16 AM on 24 January, 2012
    pirate#23: "the next part I teach is that while climate change is not the cause of the chytrid amphibian issues" Are you also informing your classes that what you are teaching goes counter to the research? What do you say if a student points to Pounds et al 2006? Analysing the timing of losses in relation to changes in sea surface and air temperatures, we conclude with 'very high confidence' (> 99%, following the Intergovernmental Panel on Climate Change, IPCC) that large-scale warming is a key factor in the disappearances. I suppose you can debate the difference between 'a key factor' and 'the cause of,' but that misses the point entirely.
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28. ClimateWatcher at 04:44 AM on 24 January, 2012
    #15 Rapid environmental changes are stressors on organisms. Can you elaborate on climate change as an environmental change in the context of diurnal change, seasonal change, and 'weather' change? All of those changes are larger in extent and very much more rapid than climate change. Also, evolution for most species has encountered numerous glacial/stadial cycles. Why would one expect selection to leave species which were vulnerable to such changes when past populations endured them?
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    Moderator Response: Your question is addressed here. Please take further discussion to the appropriate thread.
29. Paul D at 05:21 AM on 24 January, 2012
    Pirate'The Golden Toad' is assumed to be extinct partly due to global warming and its restricted range. http://www.iucnredlist.org/apps/redlist/details/3172/0 Species migration is likely to be a big factor and invasive species may wipe out native species as time goes by. I think your question is a problem because you haven't defined the range or any parameters for which you define an extinction by global warming.
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30. Paul D at 05:26 AM on 24 January, 2012
    Actually I think invasive species causing extinctions as a result of global warming is a very big issue.
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31. Phila at 06:19 AM on 24 January, 2012
    Pirate: The NCSE statement you quote at #23 explains that scientists believe that climate is changing "rapidly and significantly," and notes that we are seeing changes consistent with that scenario, "including...extinction of plant and animal species." As a teacher, surely you're aware that the term "extinction" can refer to the process of population decline, as well as to the actual disappearance of a species? In case you don't, please note Merriam-Webster's definitions: 1. The act of making extinct or causing to be extinguished; 2. The condition or fact of being extinct or extinguished. Your attitude confuses me. You seem to realize that rapid environmental changes are stressors that can cause populations to decline, and also to understand that current warming constitutes a rapid environmental change. You certainly know that migration, breeding, food and habitat are temperature-sensitive for many species. Presumably, you also understand the importance of biodiversity and the role of keystone species. If you understand all this, why then do you go so far out of your way to misread and misrepresent this NCSE statement? Your claim that the NCSE is "simply incorrect" on this point strikes me as utterly frivolous, if not disingenuous.
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32. Bob Lacatena at 07:19 AM on 24 January, 2012
    Pirate, Are the examples of extinctions that Rob Painting gave you in comment #20 insufficient?
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33. Stephen Baines at 07:36 AM on 24 January, 2012
    As a card carrying ecologist, I feel like I should step in here. There are lots of cases where climate change may be playing a role in species extinction, especially for species endemic to mountains, islands and isolated habitats, or species dependent on such habitats at key points in their life history. However, just as is the case for cancer and cigarette smoking, it is often very hard to pinpoint climate warming as the sole culprit in any one case specifically. There are so many contingencies at play. Moreover, especially at this early stage of global change, climate is usually one of several contributing factors. As with extreme climate events, it shifts the balance of probabilities. Finally, even when it is a major factor, it may act through intermediary processes that cloak the effect of climate. Temperature related stress can make species very susceptible to microbial or parasite infestations. Such has been suggested for the chytrid impacts on frogs.
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34. Rob Painting at 08:08 AM on 24 January, 2012
    Sphaerica @32 - as we have repeatedly observed facts don't alter a fake-skeptics mindset, because it is based upon a set of preconceived notions, not scientific evidence. We have seen this affliction repeatedly with Pirate. Note how he just blithely ignores the peer-reviewed scientific papers that prove him wrong? No apologies, no concession that he doesn't know what he is on about, he just repeats a falsehood as if the evidence doesn't exist. Stephen Baines - the smoking and cancer analogy is particularly apt. How many people deny smoking causes cancer? Climate skeptic Fred Singer was one, but I don't know if he's changed his tune of that yet. And essentially what I wrote in comment @10 was that humans cause extinctions in multiple ways, so yes it is hard to disentangle the effects of global warming alone - no serious 'warmist' disputes this. But given that the same bloody-minded pursuit of money by the worlds rich is also causing increased fossil fuel extraction & combustion, and the other damaging perturbations to the environment, it's all the more reason to 'about-turn' current practices.
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35. Stephen Baines at 08:38 AM on 24 January, 2012
    Rob Agreed totally. It does suggest that we move away from the species by species approach to assessing the effects of climate change on biodivrsity and think more about the problem from an epidemiological point of view, as John has, to his credit. Everything we know about past episodes of climate change suggests that we are looking at the potential for very significant loss of biodiversity in the short to medium run if temperature changes as much as predicted. It's just hard to predict which species exactly. For sure the rare, the isolated endemics and the poor dispersers are particularly prone. However, the knock on effects of such changes for other more common species, or for societies that depend in various ways on services provided by specific natural ecosystems is uncertain - in a scary way. The general thinking is that less diverse ecosystems will become more brittle and more susceptible to large state swings.
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36. Phila at 08:47 AM on 24 January, 2012
    Note how he just blithely ignores the peer-reviewed scientific papers that prove him wrong? No apologies, no concession that he doesn't know what he is on about, he just repeats a falsehood as if the evidence doesn't exist. If memory serves, Pirate also believes in "adaptation" to AGW. It seems clear that effective adaptation would require accurate risk assessment (to say nothing of presenting accurate info to young students, who'll be doing more adapting than the average middle-aged teacher). And yet, accuracy is something Pirate has ignored or resisted at virtually every turn. I wonder why that is?
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37. apiratelooksat50 at 00:13 AM on 25 January, 2012
    Rob at 20 Sorry, I was away from the computer yesterday. My original question was pertaining to extinctions directly from climate change. There are obviously instances where climate change is exacerbating other existing issues such as the chytrid fungus and that I acknowledged. In my perception that is an indirect effect. I would like to see the statement on NCES reworded to reflect that. However, I can see where we could get hung up on semantics and this could go on endlessly with no positive outcome, and therefore I will accept your position.
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38. Phila at 03:02 AM on 25 January, 2012
    Pirate: However, I can see where we could get hung up on semantics and this could go on endlessly with no positive outcome Hung up on semantics? Really? Whether you define "extinction" as a process of decline or a completed event, evidence provided in this thread proves you wrong. To insist regardless that NCES needs to change its text -- for no other reason than that you chose to read it though ideological blinders -- really is the height of arrogance. As usual, the solution here is not for working scientists to change their terminology to suit your prejudices, but for you to do your homework and develop some humility. Your students deserve nothing less. And at this point, so do the generally patient people who read these threads.
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39. pbjamm at 03:10 AM on 25 January, 2012
    apiratelooksat50@37 "My original question was pertaining to extinctions directly from climate change. There are obviously instances where climate change is exacerbating other existing issues such as the chytrid fungus and that I acknowledged." Any environmental pressure could be argued an indirect or second order effect. What would qualify as a direct effect in your opinion?
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40. Bob Lacatena at 04:50 AM on 25 January, 2012
    37, Pirate, I object to your interpretation of climate change as an indirect cause. In this case it is not exacerbating other existing issues. From Rob's quote from Pounds 2006 (emphasis mine):

    ...we conclude with 'very high confidence' (> 99%, following the Intergovernmental Panel on Climate Change, IPCC) that large-scale warming is a key factor in the disappearances. We propose that temperatures at many highland localities are shifting towards the growth optimum of Batrachochytrium, thus encouraging outbreaks.

    Simple facts:
    • Prior to the increase in temperatures, this pathogen existed but did not extinguish the species for many tens of thousands (millions? tens of millions?) of years
    • Temperature changes towards the optimum for this pathogen made outbreaks more frequent and virulent.
    • The species is now extinct.
    So climate change --> pathogen outbreaks --> extinction. Are you also claiming that in murderer --> gun --> murder, the murderer is an indirect, exacerbating factor?
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41. apiratelooksat50 at 03:58 AM on 26 January, 2012
    pbjamm at 39, There may be a causal effect between climate change and the spread of epidemic disease as described in the Pounds paper. In that case the variable of the climate causes a change in the variable of the disease. That should be considered an indirect effect. (FWIW - I do tend to support that hypothesis due to the clumping behavior of certain organsims during periods of drought.) The drought itself would be the direct effect. Other changes in weather patterns, such as frost, would also be direct effects. Other more recent research has also shown that climate change may not be linked to the chytrid outbreak as referenced in this abstract from the peer reviewed paper by Lips, et al (2008) which can be found here. "We review the evidence for the role of climate change in triggering disease outbreaks of chytridiomycosis, an emerging infectious disease of amphibians. Both climatic anomalies and disease-related extirpations are recent phenomena, and effects of both are especially noticeable at high elevations in tropical areas, making it difficult to determine whether they are operating separately or synergistically. We compiled reports of amphibian declines from Lower Central America and Andean South America to create maps and statistical models to test our hypothesis of spatiotemporal spread of the pathogen Batrachochytrium dendrobatidis (Bd), and to update the elevational patterns of decline in frogs belonging to the genus Atelopus. We evaluated claims of climate change influencing the spread of Bd by including error into estimates of the relationship between air temperature and last year observed. Available data support the hypothesis of multiple introductions of this invasive pathogen into South America and subsequent spread along the primary Andean cordilleras. Additional analyses found no evidence to support the hypothesis that climate change has been driving outbreaks of amphibian chytridiomycosis, as has been posited in the climate-linked epidemic hypothesis. Future studies should increase retrospective surveys of museum specimens from throughout the Andes and should study the landscape genetics of Bd to map fine-scale patterns of geographic spread to identify transmission routes and processes."
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42. apiratelooksat50 at 04:55 AM on 26 January, 2012
    Sphaerica at 40 Your facts are off and the analogy you presented fails miserably. The chytrid fungus is believed to be originally from Africa where it resides in local amphibian populations who have resistance to it. It was inadvertantly spread around the world originally through the actions of humans: live food trade, aquarium trade, scientific research, and boats and other equipment. Once established in other locations it can be spread by wildlife. One frog in particular, the African Clawed Frog (Xenophus laevis), has widely been transported for the above reasons. I can remember using them for experiments in high school labs, and it was even used as a human pregnancy test subject. This frog was released, or escaped, into the wild and we have various locales in North America where they are breeding. They carried the fungus with them and thus chytrid became established in our waters and our native amphibians who mostly had no resistance became infected. With no resistance, populations of different frog species throughout North and Central America were wiped out. An adequate analogy would be the introduction of the smallpox virus to the Native American population. (One of our native frogs, the Bullfrog (Rana catesbiana), does have resistance to the fungus and is also transported around the world for the same reasons and appears to be a secondary disease vector.) So, it is not your simplistic view of the fungus sitting here quietly and having no effect and then being activated by temperature changes, but instead what I referenced in the above paragraph. The optimum temperature for the chytrid fungus is 63 - 77 degrees F. Interestingly, organisms exposed the fungus have greater survivability at the higher end of the temperature range. The St. Louis Zoo even used elevated temperatures (90 degree F) to eradicate a chytrid outbreak in their hellbender recovery project. Even with that in mind, climate change does not get off the hook. From www.amphibiaweb.org "Amphibians are extremely sensitive to small changes in temperature and moisture. Changes in global weather patterns (e.g. El Niño events or global warming) can alter breeding behavior, affect reproductive success, decrease immune functions and increase amphibian sensitivity to chemical contaminants." And, finally, even the experts consider the chytrid mortality - climate change link to be "indirect" as referenced here.
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43. les at 07:19 AM on 26 January, 2012
    FWIW Mark Lynas (Six Degrees: our future on a hotter planet) explicitly touches on the above Golden Toad as the first documented climate change related extinction. He also notes the issues around chytrid etc. so: - this is now a pretty old story. - this is in chapter 1 (1° hotter) out of 6. - maybe folks teaching climate change could do worse than following David Archers' ( U of Chicago, Climate 101) advice in making the above a course book....
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44. Bob Lacatena at 07:26 AM on 26 January, 2012
    42, Pirate, Hmm, interesting that you can put that much time into researching an issue that you presume justifies your complete disdain for the concept of climate change, and yet you can't find time to research actual climate science -- the thing that you love to be so vocal about refusing to accept. But good for you, you're on the right track. You took the time to research a problem past the surface, and to learn more about it. Now if only you can apply that approach more properly and consistently to everything, instead of just the stuff that bugs you.
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45. Bob Lacatena at 07:30 AM on 26 January, 2012
    42, Pirate, From Thomas, 2006:

    Pounds et al. conclude that climate has been triggering fungal epidemics: approxi- mately 80% of the Atelopus species that have disappeared were last seen following a hot year. Cold nights inhibit fungal growth at high elevations, whereas hot days con- strain it at low elevations. In recent decades, night-time temperatures have increased and peak day-time tempera- tures have decreased (because of increased cloudiness), both of which favour the fungus. The optimal climate range for the fungus has moved up into the geographical ranges of susceptible frogs. As a result, over 90% of the harlequin frog species that used to be restricted to mid-elevations (1000–2400 m) are thought to have become extinct [8].

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46. apiratelooksat50 at 07:39 AM on 26 January, 2012
    Les at 43 There are other scientists with peer reviewed papers who think otherwise. From amphibiaweb.org. "However, Lips et al. (2008) reanalyzed the data of Pounds et al. (2006), and argued that the climate-linked epidemic hypothesis was not supported, as did Rohr et al. (2008). Anchukaitis and Evans (2010) reconstructed a century of climatic data for Monteverde, Costa Rica, and suggested that cloud forest ecology changes have been driven by natural variability in the local climate (in particular, extreme dry periods associated with El Niño weather patterns) rather than by anthropogenic climate forcing."
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47. les at 07:57 AM on 26 January, 2012
    46 - thanks, yes I did check it out in wiki and saw similar. (http://www.earth.columbia.edu/articles/view/2646). As pointed out above, ecologists are complex interconnected systems; a week link here, a pathogen there - and also links disceplens... I'd trust the biologist to know that such extinction events are enhanced by increase in climate variability: but not the origin of that variability.
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48. Stephen Baines at 08:54 AM on 26 January, 2012
    As far as I know, apirate is accurately reflecting the current trend of thinking with regard to the effect of climate on chytrid related extinctions -- in the Andes at least. There are a couple caveats, though. For one, the hypothesis for climate effects on chytrid infestation being tested in those papers is a very specific one -- namely that warming led to expansion of the chytrid range into that of the frogs, and that then led to the potential for infection and the extinctions. There are other possible mechanisms which are harder to test, though, especially on extinct species. One is that climate changes led to compromised immunity, which facilitated the movement of the disease through the population. Such immunocompromise is fairly frequent at the edges of species ranges, where environmental conditions are at the limit of a species tolerances. The thinking is that organisms at their physiological limits either expend all available energy compensating for stress, or experience some breakdown in a critical process that leads to poor performance. Because of their narrow environmental tolerances, endemic environmental specialists of the sort most commonly made extinct by chytrid are particularly prone to this effect. In this way of thinking, the chytrid is just the coup de grace that puts the species already suffering from changing climate away. It should be noted that there are clear examples of climate mediated extinction of species declines outside of the Andes - for example in central America and the SE US. Which is the right mechanism by which changing climate acts on species and what constitutes a direct and which an indirect effect? Frankly, in conservation biology it matters not a jot. What matters is what would happen if a particular factor under our control was altered in some way; would the prospects for a species persistence improve or worsen? More generally, when thinking of biodiversity loss, it's very hard to make a credible argument that changing climate will not, on average, have a net negative influence on the persistence of species, especially those with poor dispersal and high habitat fidelity. If there is such an argument, I'd love to hear it.
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49. Bob Lacatena at 09:31 AM on 26 January, 2012
    48, Stephen, But that's not the problem. Pirate's problem is that it hasn't happened yet, ever, anywhere, and therefore the NCSE bullet point on the subject of exinctions is wrong, and therefore all of their bullet points are suspect, and therefore Pirate doesn't want to teach what they say, and therefore Pirate will tell his students and everyone he knows what he has been telling them all along, which is that climate change isn't happening, isn't anthropogenic, and even if it is it won't be bad, or if it is, it isn't bad yet, and we should all sort of wait and see and keep doing what we're doing in homage to the name of the Great God the Economy.
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50. Rob Painting at 10:33 AM on 26 January, 2012
    Sphaerica- "and even if it is it won't be bad" Well, the birds, butterflies, lizards and amphibians that have already become extinct from global warming paint a rather different picture. As far as amphibians are concerned, it's hard to see much of a future for many of them. Their current rate of extinction may be 25,039–45,474 times the background extinction rate for amphibians. And that is not a typo.
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