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You're assuming that's just due to insecticides. Insects are exposed to multiple stressors. One of them also happens to be global warming. Others are habitat lo

You're assuming that's just due to insecticides. Insects are exposed to multiple stressors. One of them also happens to be global warming. Others are habitat loss, insecticides, invasive species, etc. In fact the researchers measuring the loss of insect biomass in puerto rico rainforests attributed it primarily to climate change since the other factors do not apply there.

Flozzin 8y ago
I was going to mention the same thing. I too up until the puerto rico article blamed insecticides. But something much larger seems to be going on. https://www.washingtonpost.com/science/2018/10/15/hyperalarming-study-shows-massive-insect-loss https://www.washingtonpost.com/science/2018/10/15/hyperalarm...
- campercoder 8y ago
  Climate change is causing this. Every ecoystem on Earth took 10s of millions of years to find it's equilibrium. Everything living in those ecosystems is a product of millions of years of adaptation and evolution. If you go and change the temperature, the amount of water & the seasons, then it is a big rug pull under the feet of evolution. Everything can and will collapse. Look at what is happening in the arctic... now that permafrost is melting, you have massive, uncontrolled methane release. People think that we can continue to pump CO2. We are very wrong about that. I just wish it were the pine beetles as the ones dying out.
  - aw3c2 8y ago
    You are posting hyperbole, millions of years is a bad measure to tell people that human influence is affecting. There is no equilibrium either, nature changes a lot. Look at temperature history, big changes happened again and again. https://en.wikipedia.org/wiki/Global_temperature_record#/media/File:EPICA_temperature_plot.svg https://en.wikipedia.org/wiki/Global_temperature_record#/med...
    - filoeleven 8y ago
      When people say “the climate has changed before,” these are the kinds of changes they are talking about. https://xkcd.com/1732/ https://xkcd.com/1732/ You’re right, there is no equilibrium. But there is a limit to how rapidly any system can handle changes while remaining recognizable as the same system.
    - campercoder 8y ago
      Yup, it's about the rate of change. Sucking 10s of millions of years worth of sequestered carbon out of the ground and injecting into the atmosphere over just 100 years is complete and utter suicide. For all living things on our planet.
cryptonector 8y ago
The variations in surface temperature we have seen in the modern era are nothing compared to what we've seen in the recent geological record. Moreover, insects are very sturdy throughout the geological record, so it's very difficult to believe that less than 1C change in a century could cause this (the end of the last glacial period saw a 7C swing in just a few hundred years). It's pretty clear that climate change is not the stressor causing this. EDIT: Allow me to expand. As to climate, it's an extremely complex system about we have shockingly little information in the grand scheme of things (30 years' worth of satellite data!), lots of models whose predictions have been atrocious, and besides, Earth's climate has a number of negative feedback loops, like the water cycle. We also know that CO2 and temperature in the geological record are linked, with CO2 changes lagging temperature changes, which rules out CO2 as a cause of past temperature changes. Just a very small change in cloud cover along the equator can cool down an overheating Earth, or warm a cooling Earth (depending on the direction of the change). (Readers who are curious about that should read Willis Eschenbach's work over on https://wattsupwiththat.com/. https://wattsupwiththat.com/.) But insects? We have a very plausible cause: our use and overuse of chemicals in farming, from fertilizers, to insecticides, to herbicides (which nowadays are used to kill the crops themselves as part of the process of ripening and picking them). We can be fairly certain that land use changes are not the cause: the brunt of land use changes in North America happened many decades ago, but the change in insect population density is very recent. Could the cause be something else? Yes, absolutely, but climate change is almost certainly not it -- recent climate change is minute even by standards of the past two millennia, let alone the past 18ky. And note that there is absolutely no way to test whether climate change is a cause -- how can we change the climate back in the kind of timescale we need to respond to the insect crisis in?? There aren't very many plausible causes that come to mind besides insecticides and herbicides, really, and those can be ruled in or out pretty trivially: just reduce the use of them in some large region (a few tens of thousands of acres, contiguous, say) and see what happens. The timescale for testing any hypothesis about these chemicals causing insect die-offs is on the order of... one year, maybe two -- maximum five. If insect populations don't rebound we don't need to keep using insecticides anyways, thus saving the industry a fair bit of money. There's also Occam's razor... No, pointing the finger at climate change strikes me as begging for a disaster. It's a hypothesis that cannot be tested fast enough. Insisting that we test it before testing any hypothesis that we can test in just a few years (and at a savings to industry!) is irresponsible and irrational. Science is testing falsifiable hypotheses. Here we have one. So try and falsify it. The insecticide hypothesis is cheap and easy to test, and doesn't require much time. You might argue that testing those hypotheses that are easy to test is like a drunk person looking for their car keys under the street lamp, and you might be right, but if the only other hypotheses you have are not falsifiable, then the only science you can do is: come up with more falsifiable hypos if you can, and test those you have now and come up with later. Cost is absolutely an issue, naturally, and again, the cost of testing the insecticide hypo is low, but the cost of testing the climate change hypo is simply not even within reach.
ben_w 8y ago
“Lots of insects are dying” and “insecticides kill insects” does make it very easy to reach that conclusion. I know nothing of the relevant biochemistry. Are these insecticides well targeted or highly generic in what they kill?
- deleted 8y ago
  [deleted]
- sverige 8y ago
  Most are based on organophosphates, which work basically by sending the nervous system into hyperdrive. They will kill a wide swath of animals (not just insects) if applied heavily enough. Some are deadlier to certain insects more than others. For example, Sevin kills bees even in very small doses. The other thing to note is that "loss of habitat" isn't always disappearing wetlands or stands of trees being cut down and converted to tillage. The widespread use of herbicides has almost eliminated milkweed in areas where it used to be very common, for example. When I was a kid, it was everywhere in the ditches of the Midwest. Now it's rare to see it. Milkweed is essential for monarch butterflies.
  - njarboe 8y ago
    Also these ditches and edges of farm properties are often eliminated with consolidation of farmland into larger and larger continuous acreage ownership.

Flozzin 8y ago

I was going to mention the same thing. I too up until the puerto rico article blamed insecticides. But something much larger seems to be going on. https://www.washingtonpost.com/science/2018/10/15/hyperalarming-study-shows-massive-insect-loss https://www.washingtonpost.com/science/2018/10/15/hyperalarm...

campercoder 8y ago
Climate change is causing this. Every ecoystem on Earth took 10s of millions of years to find it's equilibrium. Everything living in those ecosystems is a product of millions of years of adaptation and evolution. If you go and change the temperature, the amount of water & the seasons, then it is a big rug pull under the feet of evolution. Everything can and will collapse. Look at what is happening in the arctic... now that permafrost is melting, you have massive, uncontrolled methane release. People think that we can continue to pump CO2. We are very wrong about that. I just wish it were the pine beetles as the ones dying out.
- aw3c2 8y ago
  You are posting hyperbole, millions of years is a bad measure to tell people that human influence is affecting. There is no equilibrium either, nature changes a lot. Look at temperature history, big changes happened again and again. https://en.wikipedia.org/wiki/Global_temperature_record#/media/File:EPICA_temperature_plot.svg https://en.wikipedia.org/wiki/Global_temperature_record#/med...
  - filoeleven 8y ago
    When people say “the climate has changed before,” these are the kinds of changes they are talking about. https://xkcd.com/1732/ https://xkcd.com/1732/ You’re right, there is no equilibrium. But there is a limit to how rapidly any system can handle changes while remaining recognizable as the same system.
  - campercoder 8y ago
    Yup, it's about the rate of change. Sucking 10s of millions of years worth of sequestered carbon out of the ground and injecting into the atmosphere over just 100 years is complete and utter suicide. For all living things on our planet.

cryptonector 8y ago

The variations in surface temperature we have seen in the modern era are nothing compared to what we've seen in the recent geological record. Moreover, insects are very sturdy throughout the geological record, so it's very difficult to believe that less than 1C change in a century could cause this (the end of the last glacial period saw a 7C swing in just a few hundred years). It's pretty clear that climate change is not the stressor causing this. EDIT: Allow me to expand. As to climate, it's an extremely complex system about we have shockingly little information in the grand scheme of things (30 years' worth of satellite data!), lots of models whose predictions have been atrocious, and besides, Earth's climate has a number of negative feedback loops, like the water cycle. We also know that CO2 and temperature in the geological record are linked, with CO2 changes lagging temperature changes, which rules out CO2 as a cause of past temperature changes. Just a very small change in cloud cover along the equator can cool down an overheating Earth, or warm a cooling Earth (depending on the direction of the change). (Readers who are curious about that should read Willis Eschenbach's work over on https://wattsupwiththat.com/. https://wattsupwiththat.com/.) But insects? We have a very plausible cause: our use and overuse of chemicals in farming, from fertilizers, to insecticides, to herbicides (which nowadays are used to kill the crops themselves as part of the process of ripening and picking them). We can be fairly certain that land use changes are not the cause: the brunt of land use changes in North America happened many decades ago, but the change in insect population density is very recent. Could the cause be something else? Yes, absolutely, but climate change is almost certainly not it -- recent climate change is minute even by standards of the past two millennia, let alone the past 18ky. And note that there is absolutely no way to test whether climate change is a cause -- how can we change the climate back in the kind of timescale we need to respond to the insect crisis in?? There aren't very many plausible causes that come to mind besides insecticides and herbicides, really, and those can be ruled in or out pretty trivially: just reduce the use of them in some large region (a few tens of thousands of acres, contiguous, say) and see what happens. The timescale for testing any hypothesis about these chemicals causing insect die-offs is on the order of... one year, maybe two -- maximum five. If insect populations don't rebound we don't need to keep using insecticides anyways, thus saving the industry a fair bit of money. There's also Occam's razor... No, pointing the finger at climate change strikes me as begging for a disaster. It's a hypothesis that cannot be tested fast enough. Insisting that we test it before testing any hypothesis that we can test in just a few years (and at a savings to industry!) is irresponsible and irrational. Science is testing falsifiable hypotheses. Here we have one. So try and falsify it. The insecticide hypothesis is cheap and easy to test, and doesn't require much time. You might argue that testing those hypotheses that are easy to test is like a drunk person looking for their car keys under the street lamp, and you might be right, but if the only other hypotheses you have are not falsifiable, then the only science you can do is: come up with more falsifiable hypos if you can, and test those you have now and come up with later. Cost is absolutely an issue, naturally, and again, the cost of testing the insecticide hypo is low, but the cost of testing the climate change hypo is simply not even within reach.

ben_w 8y ago

“Lots of insects are dying” and “insecticides kill insects” does make it very easy to reach that conclusion. I know nothing of the relevant biochemistry. Are these insecticides well targeted or highly generic in what they kill?

deleted 8y ago
[deleted]
sverige 8y ago
Most are based on organophosphates, which work basically by sending the nervous system into hyperdrive. They will kill a wide swath of animals (not just insects) if applied heavily enough. Some are deadlier to certain insects more than others. For example, Sevin kills bees even in very small doses. The other thing to note is that "loss of habitat" isn't always disappearing wetlands or stands of trees being cut down and converted to tillage. The widespread use of herbicides has almost eliminated milkweed in areas where it used to be very common, for example. When I was a kid, it was everywhere in the ditches of the Midwest. Now it's rare to see it. Milkweed is essential for monarch butterflies.
- njarboe 8y ago
  Also these ditches and edges of farm properties are often eliminated with consolidation of farmland into larger and larger continuous acreage ownership.