Why Evolution Is Misunderstood
    By Gerhard Adam | November 30th 2010 12:09 AM | 6 comments | Print | E-mail | Track Comments
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    In reviewing this article, I couldn't help but notice the problems in how this information was reported, so that it became quite apparent why the general public perpetually misunderstands or misinterprets evolution.

    "Our results demonstrate, for the first time, that Coal Forest fragmentation influenced profoundly the ecology and evolution of terrestrial fauna in tropical Euramerica, and illustrate the tight coupling that existed between vegetation, climate, and trophic webs." (Abstract)

    "Specifically we test the hypothesis that population constriction into isolated rainforest islands exerted a major impact on tetrapod diversity, ecology, and the development of endemism. In doing so, we draw on the theory of island biogeography (MacArthur and Wilson,1967), which was developed to explain patterns of diversification in oceanic islands, but is equally applicable to other kinds of islands, e.g.,rainforest refugia."(1)

    So effectively we have a paper that indicates that the fragmentation of the rainforests into "islands" created the kind of diversity and endemism as predicted by the theory of island biogeography and is even referenced in the article as a "classic ecological response".  So what happened when this got translated for the public?

    "Global warming devastated tropical rainforests 300 million years ago."
    While the original paper states "In cratonic areas of North America (where the effects of tectonics can be excluded), an abrupt shift to more arid climates has been linked to rainforest collapse (DiMichele et al., 2009, 2010), though the exact causal mechanism remains uncertain. One hypothesis is that aridification was triggered by a short-term but intense glacial phase."

    So it begins with the reporter clearly taking liberties with a particular perspective which is intended to foster a particular agenda.
    "Now scientists report the unexpected discovery that this event triggered an evolutionary burst among reptiles -- and inadvertently paved the way for the rise of dinosaurs, 100 million years later."
    What's interesting in this quote is the use of the word "inadvertently" as if evolution proceeds with intent or purpose under normal circumstances, but it completely missed the collapse of the rainforest so there was some unusual twist in what came next.  There is nothing intentional about evolution, so in one way, everything that occurs is "inadvertent". However, while I realize that this usage originated with the reporter, it is a clear indication of the kind of sloppy scientific journalism which is such a problem.  I'm also not clear on what precisely was "unexpected" in this paper.  
    "But when the Earth's climate became hotter and drier, rainforests collapsed, triggering reptile evolution."
    Once again, the problem is that it suggests that evolution occurs with a purpose and that it is normally dormant until some event "triggers" it.  At this point the reporter has reversed causation by indicating that it was the hotter, drier climate which gave rise to the rainforest collapse, instead of reporting as indicated earlier that the rainforest collapse (cause still uncertain) is what gave rise to increased aridification.

    However, even the original authors aren't exempt for embellishing the results in directions not demonstrated by the study.
    Ms Sarda Sahney, also of the University of Bristol, UK said: "It is fascinating that even in the face of devastating ecosystem-collapse, animals may continue to diversify through the creation of endemic populations." However, she warned that: "Life may not be so lucky again in the future, should the Amazon rainforest collapse."
    I can't even begin to imagine what she was thinking when she said this.  Of course, diversity tends to increase when environments change, since this provides the greatest opportunity for natural selection to operate.  The more new niches open up, the greater the opportunity for modifications to find a place to thrive.  This is hardly unexpected, although it is equally not assured.  However, the statement about the Amazon rainforest is truly baffling.  Are we to believe that life on Earth is threatened by the collapse of the Amazon?  Surely she can't be that naive.  This is the kind of propagandist nonsense that turns legitimate scientific inquiry into political agendas.  Life is certainly not in jeopardy, regardless of what happens to the rainforest.  Certainly HUMAN life might have problems, but life on Earth is not the issue.  To suggest otherwise is making a claim with no scientific backing.
    "They showed that reptiles became more diverse and even changed their diet as they struggled to adapt to rapidly changing climate and environment."
    In this final statement of the article it once again suggests that evolution (or natural selection) operates with a purpose, as if a species "struggles" to find its proper adaptation for the new circumstances.  This kind of verbage simply promotes a general misunderstanding of evolution and natural selection and is a disservice to serious scientific inquiry.  When this is linked to the popular mythology that only random mutations can initiate changes, it's little wonder that most people find this type of "science" hard to believe.

    (1) Rainforest collapse triggered Carboniferous tetrapod diversification in Euramerica
    Sarda Sahney, Michael J. Benton and Howard J. Falcon-Lang


    Very disheartening. As a layman and consumer of science writing, I rely on professional science writers to "translate" scientific papers into English and to let me know the importance of the research in context. To just make up stuff is so wrong!


    Thanks for posting this. In general I agree with what you're saying. It has wider applicability, I think, than just public misunderstandings about evolution and global warming. This was a press release from the University of Bristol, and the person writing it was probably not very familiar with the subject, which is quite dry and technical. Somehow it has to be put in a form that the average reader might find understandable and even interesting.

    Imagine if you wlll the following reaction: "Fred, guess what I just learned! The tetrapod radiation in Euramerica during the Carboniferous was probably due to rainforest fragmentation!"

    Note likely, because understanding this result at all requires you to know:

    a) Once there was a place called Euramerica. It was a fusion of eastern North America and northern Europe.
    b) Much of it was covered with swamps and rainforest, and the animals that lived there were mainly amphibians,
    c) An abrupt change in climate 300 million years ago caused the rainforests to dry up, and the amphibians were replaced by a wide variety of reptiles.
    d) The reason for the climate change is basically unknown, although it may have been initiated by a short-lived ice age.
    e) The sudden diversity of reptiles has always been thought to be the evolution of the amniote, an egg that can develop outside a watery environment.
    f) We think it was also due to an "island" effect when the rainforest was split into many smaller pieces.

    Both the authors and the press writer, for their own reasons, are trying to make this result sound important and exciting. Most research is neither.

    To give the reader something familiar to relate to, the story mentions:
    a) The changed climate was warmer than before ("global warming")
    b) Some of the reptiles eventually evolved into dinosaurs, and yes, this was "inadvertent" in the sense that an observer in the Carboniferous could not have predicted such an outcome, which also depended on many other factors as well.
    c) The closest thing we have to a tropical rainforest today is the Amazon. If the Amazon dried up, it would have a "devastating" effect on most of the existing animals, but might be "unexpectedly" beneficial to others.

    Global warming has become so politicized that it's difficult to say anything about it without sounding like you have an axe to grind. If anything, I think the conclusion of the article is positive, that even seeming disasters can in the long run produce unexpected benefits.

    Gerhard Adam
    Bill, thanks for a thoughtful response.  Unfortunately the problem with this research is that it really isn't terribly exciting.  Even your point about reptiles and the amniote is kind of a "chicken and egg" (sorry about that) problem, because clearly this is precisely what shifted the advantage to reptile diversity when water supplies dried up.

    All in all, I'm not clear (even after reading the paper) how this was anything except a basic confirmation of the theory of island biogeography.  I think part of the point was to demonstrate a geographic dependency evolving (endemism) much like that shown in the Galapagos.  However, I'm not sure why this was considered significant, beyond simply verifying what was expected.

    In short, did anyone truly expect a different result?
    Mundus vult decipi
    Science is not about expecting a result - the progress of science is littered with unexpected results. That's why we carry out studies like this one. Interest, excitement and so forth are subjective to the reader.

    Gerhard Adam
    Did you actually read the article?  An "unexpected result" is one thing, but not when it is used to hype a non-discovery.
    Mundus vult decipi
    "Global warming devastated tropical rainforests 300 million years ago." <-article
    G.A. wrote: So it begins with the reporter clearly taking liberties with a particular perspective which is intended to foster a particular agenda.

    The 1st sentence is not the reporter. It is a quote from the U Bristol press release. You bringing up the cooling phase and then misdirect the reader by omitting the subsequent shift to warmer conditions. -
    "The cooler, drier climate conditions were not favourable to the growth of rainforests and much of the biodiversity within them. Rainforests shrank into isolated patches, these islands of rainforest were mostly confined to wet valleys further and further apart. Little of the original lycopsid rainforest biome survived this initial climate crisis, only to survive in isolated refugia.
    Then a succeeding period of global warming reversed the climatic trend; the remaining rainforests, unable to survive the rapidly changing conditions, were finally wiped out."