Claim: Evolution Too Slow to Keep Up With Climate Change

This is junk science because…

… studying evolutionary family trees is not science at all… it’s guesstimation that can’t be verified by the scientific method. The process of science is not the process of developing BS rationalizations based on cherry-picked interpretations of guesswork.

Science Daily reports:

Many vertebrate species would have to evolve about 10,000 times faster than they have in the past to adapt to the rapid climate change expected in the next 100 years, a study led by a University of Arizona ecologist has found.

Scientists analyzed how quickly species adapted to different climates in the past, using data from 540 living species from all major groups of terrestrial vertebrates, including amphibians, reptiles, birds and mammals. They then compared their rates of evolution to rates of climate change projected for the end of this century. This is the first study to compare past rates of adaption to future rates of climate change.

The results, published online in the journal Ecology Letters, show that terrestrial vertebrate species appear to evolve too slowly to be able to adapt to the dramatically warmer climate expected by 2100. The researchers suggested that many species may face extinction if they are unable to move or acclimate….

“We found that on average, species usually adapt to different climatic conditions at a rate of only by about 1 degree Celsius per million years,” Wiens explained. “But if global temperatures are going to rise by about 4 degrees over the next hundred years as predicted by the Intergovernmental Panel of Climate Change, that is where you get a huge difference in rates. What that suggests overall is that simply evolving to match these conditions may not be an option for many species”….

For their analysis, Quintero and Wiens studied phylogenies — essentially evolutionary family trees showing how species are related to each other — based on genetic data. These trees reveal how long ago species split from each other. The sampling covered 17 families representing the major living groups of terrestrial vertebrates, including frogs, salamanders, lizards, snakes, crocodilians, birds and mammals.

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14 responses to “Claim: Evolution Too Slow to Keep Up With Climate Change

  1. Since species can’t adapt to climate change faster than 1°C/million years, where were all the mass extinctions from the Medieval Warm Period and Little Ice Age? I suspect the earth’s flora and fauna are a bit hardier than these guys believe.

  2. It’s my understanding that many significant evolutionary changes are episodic in response to some new challenge in the environment. Also, did the authors consider that an organism’s ability to acclimate to environmental changes might obviate the need for major evolutionary changes in response to small changes in the climate.

  3. Climate is one of the drivers of evolution, this “study” is looking at it ass-backwards.

  4. I’m hard pressed to think of an animal that isn’t subjected to more than 4° temperature swings on a daily basis. A seasonal temperature change of 40° is perfectly normal in much of the world. Of all the specious claims made to support the “catastrophic” portion of CAGW, this is possibly the least scientifically supported. I think the authors have spent too many summers in climate controlled offices staring at averaged, weighted, and smoothed graphs. In the real world organisms don’t need evolution to deal with a 100-year increase in average temperatures that is less than many locales experience from one year to the next.

  5. of course, that’s why there’s no life left on Earth [/sarc, for those in Rio LInda]

  6. It’s worth mentioning that the blog author cut off the bit of the article that deals with other ways species get around shifts in climate change. It’s also worth mentioning that the article is referring to changes in average temperature which effect extreme high and low points which is where the climate kills off animals, not daily fluctuations in temperature which obviously would be absurd.

    • Extreme high and low points may “kill off” animals, but the article is clearly suggesting that a small increase in maximal high temps could cause the extinction of species due to inability to evolve fast enough. When extreme heat or cold kills individual animals it is generally in conjunction with other weakening factors such as age, disease, or hunger. These deaths are integral to the ongoing process of natural selection that drives the species as a whole. The switch from adaptability of species over generations to survivability of individual animals is a classic example of mid-stream definition change favored by people who are either deliberately spreading misinformation, or simply misunderstanding the topic themselves.

  7. Natural selection by definition occurs over multiple generations, it by definition requires time to occur. For instance one of the earliest evolution experiments involved a scientist taking several containers of identical bacteria and heating and cooling them in different ways and rates, he took one container and heated it up until they all died, then he took another and heated it up to the temperature the first group could not survive at, but did it gradually over several years, which produced bacteria that thrived at the hotter temperature, but could now no longer tolerate the cooler temperatures the initial population thrived at, so when he cooled them suddenly it killed them all. That evolution takes time and that sudden change is less adaptable than gradual change is not controversial.

    • I’m not sure whom you are debating as that’s kind of what I said. The argument proposed is that a long gradual change over 100 years (much longer than the generation length of most species) would be too fast. Most species experience larger changes in temperature during a single generation. To claim that a change of 0.04 degrees per year is rapid enough to kill off an entire species at once when the much larger change of temperatures from one season to the next does not, is ridiculous. To compare that rate of change to cooking or freezing a petrie dish over the cours of a few minutes is even worse. “Rapid change” on a geological time scale is similar to “near-miss” to astronomers, great for making headlines, but ultimately not much of a threat. Of course I’m sure we could cobble together a hypothetical worst case scenario in which an entire species might die simultaneously. Extinction has happened before, but that’s also part of my point. Extinction is itself a natural part of the process that’s been ongoing before we even got here. If a species isn’t adaptable enough to cope than it should be supplanted by a more suitable species.

      Of course, we haven’t even broched the topic of migration as a form of adaptation, so I’d love to hear more counter arguments.

      • Again it’s not about the day to day or season to season changes, it’s about the averages changing which changes the extremes. A ten degree shift in the average temperature means the highest or lowest temperature in the year is going to be ten degrees higher or lower, which is a big difference, especially to species more sensitive to changes in temperature. And a handful of generations is not enough time to adapt, useful genetic variations cannot spread very far in that time and if most of the species gets wiped out then they lose a huge portion of their genetic diversity and thus cannot adapt to all the other things, like disease, predators and so on that they have to in order to survive.

        You can disagree that climate change is happening too fast (and for all I know you’re right), but the principle that it could be too fast is perfectly valid. And yes species do go extinct but I’d rather they not go extinct because of something we did. And I’d rather they not go extinct when there could still be things to be learned or gained from them. What if some plant dies out because of climate change that held a cancer cure?

        • I never said that temperature changes could not occur too fast to kill off an animal, but in your own argument concerning the bacterium, the temperature change did not occur too fast for evolution to keep up. It occurred too fast for a subsequent generation to be born in the first place. The same result could be had by just chucking the Petri dish in a bucket of bleach. Had he heated the dish until half the population died, waited, and then repeated, we could potentially see whether the population was ever able to out breed the change and return to maximum population density. As it is, the death of the colony only proved the maximum of the colony’s temperature range.
          Local extreme temperatures are outliers that are factored out of the trend of global warming. My point is not that the temperature range is what kills individual animals; it is that a change of .04C per year is too small to encompass much larger changes to the temperature range. This is why highest temp-day records are scattered randomly across the decades and aren’t considered relevant to the global warming trend (at least that’s the most prevalent argument I’ve read). Moreover, the predictions are for increased winter low temperatures occurring north or south of the tropics. The warmer a location is now, the less it will experience local warming. The argument that it is only extreme temperatures that kill individual animals is not contrary to my point. The projected 0.04C annual change isn’t large enough to be a threat.
          I’m unable to find any research that discovered how many generations it takes to adapt to a specific temperature range, but the question is more to do with whether adaptation is necessary. The habitable temperature range for a species is generally much larger than the comfortable temperature range. A person may die of heat stroke if they move from Maine to Florida and don’t change their hydration and activity habits, but that’s a change of tens of degrees in a day and it’s still manageable with acclimatization. No need for adaptation. The need for adaptation, and therefore, the danger of death, only happens at the boundaries of the species’ potential temp-range. It is therefore unlikely that an entire species or even a significant portion of a species (as it would be the least-hardy individuals that die first) would die simultaneously from the same extreme heat or cold event. The removal of those less hardy individuals from the gene pool prevents the passing on of weaker examples. As the other animals lived, they already have the hardier genes necessary for survival so there is no need for adaptation. That is the difference between natural selection within a species and evolution across species. It is a reduction of weaker variables which makes room for the proliferation of stronger ones. The more high temperature events that occur at the boundary of the species’ capability, the less likely an extinction event will occur as a result of one. Unless you’re making the argument that the proposed 4 degrees in 100 years would include an increase of the maximum temperatures of tens of degrees (which would require cooler than normal non-extreme days to reach the average), I just don’t buy the prediction. Besides, as I alluded to earlier, given the long time range, susceptible animals that are capable of migration could simple out-walk the temperature change.
          I consider mankind to be a part of nature, not a force from outside of it. Millions of species came and went before we got here. I find it likely millions more will come and go after we’re gone. The mythical plant that cures cancer is a hypothetical red herring. Here we’ve degraded into opinion and philosophy rather than math and science and I’m already too long-winded. It’s been a pleasure conversing with you.

          • “in your own argument concerning the bacterium, the temperature change did not occur too fast for evolution to keep up. It occurred too fast for a subsequent generation to be born in the first place.”

            That’s the same thing.

            “Had he heated the dish until half the population died, waited, and then repeated, we could potentially see whether the population was ever able to out breed the change and return to maximum population density.”

            As I said before even that amount of death on a species-wide level would probably result in extinction anyway because of the lack of genetic diversity and adaptability that would result. Once a species gets below a certain population they are almost definitely doomed to extinction from genetic meltdown. The notion that natural selection is 99% of a species getting wiped out, then the species repopulating, then the same thing happening over again is incorrect, it’s usually about genes accumulating or becoming less common gradually because they make the individuals that possess them slightly or somewhat more or less likely to survive.

            “A person may die of heat stroke if they move from Maine to Florida and don’t change their hydration and activity habits, but that’s a change of tens of degrees in a day and it’s still manageable with acclimatization. No need for adaptation.”

            Humans adapt our environment to ourselves, as you say by changing our diet and routine, species cannot do that. A species may adapt by evolving a different set of behaviors (being less active, being more thirsty or drawn to water etc) but overall natural selection allows any adaptation that is useful to accumulate, it does not pick one and ignore another. Do you reject evolution in general, that for instance mammals are a subset of reptiles and can survive in dramatically colder environments than any reptile?

            “It is therefore unlikely that an entire species or even a significant portion of a species (as it would be the least-hardy individuals that die first) would die simultaneously from the same extreme heat or cold event.”

            Extinction doesn’t require every individual to suddenly drop dead, just for, on average one more animal in a generation to die than is born. And in nature lots of things kill animals before they can reproduce, not just the climate.

            “As the other animals lived, they already have the hardier genes necessary for survival so there is no need for adaptation.”

            There is if the environment keeps changing.

            “That is the difference between natural selection within a species and evolution across species. It is a reduction of weaker variables which makes room for the proliferation of stronger ones.”

            I don’t understand what you mean by that. And speciation is to do with genetic isolation or divergent evolution, I don’t see what it has to do with anything we’re discussing.

            “Besides, as I alluded to earlier, given the long time range, susceptible animals that are capable of migration could simple out-walk the temperature change.”

            An environment will often change and only the ones that have wandered out of it will survive, but species do not magically know to leave an environment or have any concept of there even being another place, barring species that have a migration instinct. So if say the US got really hot the only species that would survive would be the few that are already in canada. Global events that happen too fast for life to adapt generally wipe out everything except a handful of species that happened to be able to survive in their new environments which then branch out and repopulate the planet.

            “Millions of species came and went before we got here. I find it likely millions more will come and go after we’re gone.”

            I agree. But I don’t want to cause a mass-extinction, do you?

            “The mythical plant that cures cancer is a hypothetical red herring.”

            Cancer specifically, sure, but I was just using an example. Plants having medicinal properties is hardly hypothetical.

            “It’s been a pleasure conversing with you.”

            Likewise : )

  8. Actually Cheetahs are practically clones due to past near extinctions that they repopulated from. Look to the successes of the endangered species list for more examples of animals that have come back form the brink.

    Also most species that are being tracked by biologists change their range as the environment changes around them. The changing range of armadillos in north america is often cited as a sign of past warming (the range moved north during the thirties and began moving back south during the cooler 70’s when alarmists were crying ice age. Recently they are moving north again. Perhaps migration is the wrong word. I don’t mean it in the seasonal sense as birds do, but in the slow shift in range that occurs as a response to habitat change. Again this doesn’t even require one generation. Few animals will simply sit still and die if conditions are worsening.
    The proposal that “Every species has a climatic niche” as stated in the article is a gross mischaracterization. The word niche hardly seems appropriate for the many species that can be found on multiple continents.

    Ultimately, my issue with the above claim is that the proposed rate of change is nothing to be concerned about. It’s far from the fastest rate of change in history. Some animals may go extinct given many compounding factors (too small breeding pool, geographic isolation, increased predation…), but the statement “Many vertebrate species would have to evolve about 10,000 times faster than they have in the past to adapt to the rapid climate change expected in the next 100 years” Is meaningless. Adaptation is a response to change and therefor can not happen faster than change. If the claim is that the climate has never changed this fast before (not supported by the geological records), then of course adaptation has never occcured this fast either. I brought up speciation in order to narrow my definitions. Evolution is the accumulation of random mutation and is independent of outside conditions (excepting potentially mutagenic conditions such as high radiation levels). Adaptation is the shifting in the population density of various genetic potentials already available to the breeding pool (such as more fair skinned people living in the north where sunlight is weaker and more dark skinned people living near the equator). The story specifically claims evolution would have to occur faster, but slow, steady-rate evolution is an old, abandoned premise that has largely been suplanted by punctuated equilibrium. Many extant species such as crocodilians are believed to be barely changed over the course of the last millions of years and that time period encompasses many short term climate shifts that occured faster than the one projected by the IPCC.

    Historically it has been cold rather than warmth that is linked to most mass extinction events. Warming is generally associated with increases in biodiversity as more land mass is opened up to species that require the quantities of food only found in warmer climates.

    As far as the potential loss of medicinal plants or other organisms, I would contend that a bird in the hand is worth two in the bush. The proposed limitations on the cheapest forms of energy would have a much more measurably negative impact. A simple comparison of life expectancy and infant mortality pre and post industrial revolution shows that the rapid pace of scientific advancement is beneficial. To sacrifice the known benefits of one system for the sake of potential benefits in another isn’t a solid enough argument to me.

    I do not want to cause a mass extinction event, unless it’s beneficial to the human race long term (think small-pox). I would love for mankind to be responsible for the extinction of the parasitic protozoans which cause malaria. We were able to accomplish this feat in north america decades ago. fears of another potential economic impact prevented us from doing the same for many other nations.

    Ultimately, a few organisms may go extinct but it would be difficult to blame this solely on warming without other extenuating factors. I’m not arguing that things like habitat loss, predation changes, localised famine or drought can’t kill off a species. But warming on its own at a steady rate of 4C per century does not warrant the alarmist sensationalism of the article’s title.

    I just deleted a few paragraphs of point for point refutation of tangentially related points because this is long as it is. I’m just an optimist I guess, but I have no experimental evidence to support my optimism other than the past several thousand end of the world scenarios failing to materialize. I would argue, that they don’t actually have any experimental evidence to support their pessimism either. The Ordovician-Silurian extinction is believed to have been caused by glaciation. The Late Devonian extinction is suspected to be due to global cooling. The Cretaceous-Tertiary extinction was blamed on asteroid impacts darkening the sky and causing sudden global cooling. When I was a kid in school all of the past mass extinctions were blamed on very rapid global cooling. I see now that a few are being blamed on volcanic global warming, but that really just makes me question more to what degree mankind can really be held responsible. Also they’re in direct conflict with many established theories about the effects of airborn volcanic ash. Namely that it causes cooling.

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