Opinion: Why Evolution is Essential

By current PhD student Jennifer Cochran Biederman. This piece originally appeared as a guest view in the Winona Daily News on October 27th, 2008

Vice presidential candidate Sarah Palin has spoken in favor of Creationism (or Intelligent Design), signaling that it’s as important as ever to set the record straight on evolution. And coupled with global warming, habitat loss and other mounting pressures on ecosystems, understanding the role of evolution in biodiversity is critical n and an essential component of our K-12 education.

So what exactly is evolution?

Well, in case your science teacher happened to skip that all-important section of the textbook (which many do), here’s evolutionary theory in a nutshell. Random changes in genetic material (mutations) and competition for scarce resources can cause a species to change gradually over time.

Eventually, new behavioral, morphological and physiological adaptations are reflected in the organisms’ DNA, and a new species is generated. Such speciation, as scientists call it, takes a long time. In other words, an ape didn’t magically transform into modern man overnight – as many Creationists imply evolution to claim. In fact, it has taken man nearly 7 million years to evolve from the first hominids which were a short species (less than 1.5 meters tall) that walked upright, had a protruding jaw, distinct eyebrow ridges and a small brain.

So why is evolution only a theory?

Well it is, and it isn’t. New species arising by means of evolution is considered a fact (scientists can indeed demonstrate this); however, the mechanism by which evolution occurs remains theoretical. One of the world’s most widely respected evolutionary biologists, Douglas J. Futuyma, can explain this a bit more eloquently:

“The theory of evolution is a body of interconnected statements about natural selection and the other processes that are thought to cause evolution, just as the atomic theory of chemistry and the Newtonian theory of mechanics are bodies of statements that describe causes of chemical and physical phenomena. In contrast, the statement that organisms have descended with modifications from common ancestors – the historical reality of evolution – is not a theory. It is a fact, as fully as the fact of the Earth’s revolution about the sun.” (From Evolutionary Biology second edition, 1986)

Indeed, the argument for evolution is strong, and the fact that it remains an afterthought or an intentionally avoided piece of the curriculum is nothing short of astonishing. Without a solid understanding of basic evolutionary principles (such as natural selection, adaptation and speciation), we are failing our children, who, in America, continue to lag behind in science literacy.

Scientists and academics have clearly established evolution to be at the core of virtually all biological disciplines – ecology, microbiology, immunology and more. Pick up a peer-reviewed journal in any of these topics, and page through to find up to half of the research – if not more – conducted in the context of evolution. This generation of students makes up our future doctors, ecologists and microbiologists, and in order for them to be adequately prepared for undergraduate science curricula and research, it is essential that grade school biology be taught in the context of evolution. In fact, nearly every major university offers a program in ecology and evolutionary biology, which is often an interdisciplinary department comprised of a wide breadth of academic subjects including biology, anthropology, chemistry, math and even English.

So if evolution is all over higher education, then why hasn’t it trickled down to the K-12 curriculum?

As long as the number of American adults who believe that humans did not evolve from an earlier species continues to rise (from 46 percent in 1990 to 54 percent in 2005), there seems to be little hope. But in spite of popular opinion, evolution has never been more important – or more relevant.

Scientists use evolution to understand a broad range of human health problems. It explains antimicrobial resistance, the possibility of the avian influenza virus to mutate into a human pandemic influenza virus, and the emergence of novel pathogens that can infect plants, animals and humans.

And as it turns out, evolution is even important as we study the impacts of global warming. Even as the Earth has warmed a humble one-half of one degree in the past 25 years, scientists have observed rare instances of warming-induced evolution already taking place.

Remember that in order for evolution to occur, the gene frequency of a population must be altered. So an organism reproducing earlier or expanding its home range isn’t necessarily an evolutionary indication unless it can be traced to a genetic shift in the population. Indeed, scientists have been able identify a distinct genetic shift related to warming temperatures in more than a few situations.

In 2006, an article published in Science documents evolution in response to climate change. The authors describe how Blackcaps, a central European bird, are increasingly overwintering in Britain instead of Iberia. The warming-induced evolution of this species is demonstrated by a genetically distinct British subpopulation that arrives at the nest earlier and obtains better territories and mates, allowing for reproductive advantages. Likewise, another European bird, the great tit, has shown genetic variation in terms of which individuals are able to adjust their egg-laying date in response to the earlier, warming-induced maturation of their food source – caterpillars. Those that can adjust maintain the greatest reproductive success.

Scientists can still tell more stories of the observed occurrences of evolution caused by climate change. While it’s fascinating to observe evolution in action, it’s scary to consider how such a modest temperature change has already impacted biodiversity. Therefore, it’s more important than ever to educate our kids – and us – about evolution and global warming. Both are central to understanding the dynamics of our biodiversity and, more importantly, what we can do to save it.

And one final note: Is it possible to be Christian and a supporter of evolution?

To the contrary of the Creationist claim, emphatically, yes!

Many Christian denominations – including Catholicism – wholly accept evolution. That’s not to say the story of Adam and Eve doesn’t have significance. It having been divinely inspired and carefully constructed makes its allegorical power and significance much more meaningful than if it were simply a factual documentation of the events surrounding the creation of man. In my own humble beliefs, I can’t rule out that a process that’s often so utterly perfect and creatively complex as evolution might just be held in the hands of a higher power.

About the author:

Jennifer Cochran-Biederman is a 1st year Phd student in the Conservation Biology Program at the University of Minnesota. She studied the evolutionary ecology of an assemblage of Neotropical cichlids for her master’s work at Texas A&M, and her current graduate project examines the seasonal variation of trout growth in southeastern Minnesota.

Have an informed opinion about something science related? Let the Cons Bio Blog be your platform! Submit a guest blog, here!

PLEASE NOTE: Opinion blogs do not necessarily represent the unanimous opinion of those affiliated with the Conservation Biology Program at the University of Minnesota. Rather, they are meant to broaden and elevate the educational and scientific discourse related to various topics in conservation biology.

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What I do: An exercise in hyperbole

By current PhD student Marcus Beck

One of the challenges of a graduate education is learning to effectively communicate the importance of your research.  Perhaps even more of a challenge is simply communicating what you do on a daily basis to friends, relatives, or even students within your program.  Over the years I’ve provided a variety of answers to questions about what I do and why it’s important, changing the tone and context of my answers to cater to the interests of whomever was asking.  To be fair to myself, my interests and goals haven’t always stayed constant during my four years in the Conservation Biology program.  I’d like to think that what I’m doing now is linearly related to my past experiences both at the University and prior, but it’s not.  The learning process is hardly ever linear given the diversity of external factors that push and pull you in different directions.

Rather than provide a cliché and predictable story that describes why I love the natural world (and believe me, I could), I want to start with the most easily describable reason for my current research direction.  This reason relates explicitly to legal requirements that are mandated by the federal government, and in turn dictated within Minnesota’s state rules for protecting natural resources.  I direct your attention to state rules, chapter 7050.0150, subpart 6C:

DETERMINATION OF WATER QUALITY, BIOLOGICAL AND PHYSICAL CONDITIONS, AND COMPLIANCE WITH STANDARDS, Impairment of biological community and aquatic habitat.

In evaluating whether narrative standards […] are being met, the commissioner will consider all readily available and reliable data and information for […] an index of biological integrity calculated from measurements of attributes of the resident aquatic plant community.’ MN rules 7050.0150.6C

Minnesota’s resource management agencies are required to use aquatic plants, among other organisms, to determine if the condition of a waterbody is acceptable for use by society and aquatic life.  This mandate is ultimately linked to federal requirements under the 1972 Clean Water Act for state governments to ‘protect, maintain, and restore the biological integrity of the nation’s waters.  As an abstraction, these laws also implicitly reflect decades worth of societal statements of value directed towards the environment.

The elusive aquatic macrophyte.

Within the framework of these legal requirements, my Masters work was focused on developing an index of biotic integrity using aquatic plants to assess the condition of lakes in Minnesota (see here for more info).  This index is intended for use by Minnesota’s resource management agencies to assess whether lakes fulfill water quality standards.  The project, as I saw it, was an exercise in applied science such that the need for this index is clearly articulated in state legislation, which in turn was mandated, however loosely, by federal legislation.  Communicating the need for this project to relatives, friends, or colleagues usually involved some variation of the above explanation to convince the interested parties that there is a real basis for my work grounded in legal doctrine that validated my existence as a graduate student.

Framing my research within the context of legal requirements, however legitimate, is obviously an easy answer to a complicated question.  A more admirable approach is to convince others of an internal motivation for my research, a task that I view as a central challenge towards attaining a graduate degree.  As such, I view the current legislative framework for my research simply as a vehicle within which I, and others concerned with the protection of natural resources, can frame our work.  The impetus of my dissertation work is rationalized by the first line of the first section of the Clean Water Act.  Like most federal documents the details are generally nondescript, allowing considerable freedom in defining different approaches for fulfilling stated objectives.  State rules reflect a single interpretation of these nondescript federal requirements.  A broader challenge has been developing my own interpretation of this legislation for my current dissertation project.  Rather than viewing myself as being constrained within the applied context of environmental policy, I see myself as having the freedom to develop my own definition of the law.

An aquatic plant survey.

Developing an interpretation of a loosely defined legal document does not come without challenges.  Indeed, a challenge for implementing biological assessment methods within larger resource management programs has been the explicit identification of causes of biological response.  Consider the information provided by a biological survey.  The survey might indicate that ‘x’ number of species are present, the diversity of species is within some range, a high proportion of invasive species dominates the community, and so on.  This information can be synthesized within a numerical index to indicate the quality of the biological community.  A score falling below a predefined threshold necessitates a declaration of impairment by the agency that manages the resource.  However, in order to remediate the impairment, an immediate cause that contributed to the impairment needs to be identified.  Unfortunately, a biological response rarely indicates the cause(s) of poor condition.  In many cases, the contributing cause might act across time and space and may even be a suite of multiple factors acting synergistically.

Identifying causes of biological impairment is no easy task.  The Environmental Protection Agency is hard at work developing a framework that will assist state agencies in drafting remediation plans for biologically impaired waters.  The science of stressor identification is in its infancy and researchers have the opportunity to develop novel approaches for identifying stressors that cause impairment.  Undeniably, restoration of the natural environment requires a combined effort by all practitioners and stakeholders (any self-respecting Conservation Biology student is aware of this).  As such, my dissertation work focuses on unexplored components of the stressor identification process to facilitate the broader challenge of restoring the biological integrity of Minnesota’s lakes.

A classified image of land use (top) and a color-infrared aerial image of a nearshore lake area (bottom).

So what exactly am I doing and why is it important?  One of my primary tasks is to develop an approach for better quantifying potential stressors that negatively impact aquatics plants.  The residential development of nearshore areas of lakes (e.g., houses, docks, etc.) in Minnesota has increased drastically within the last two decades (check out this Star Tribune article).  Like most contemporary environmental problems, our ability to understand the impacts of these activities has not kept pace with our ability to provide practical solutions.  A perfect example is the availability of data to quantify information that can be used to model effects on biological organisms.  Current land use and land cover data provide inadequate spatial resolution for quantifying potential stressors in nearshore areas.  A cell size for a typical map layer is 900 square meters, as compared to the size of a dock, which usually doesn’t exceed 15 square meters.  Fortunately, high resolution aerial photos (1m resolution or better) are available for the entire state. The challenge is to convert the raw, pixel-based information into meaningful data that can be interpreted in an ecological context.  For example, pixel-based information is captured by cameras and stored as digital values.  Man-made structures, such as docks, have pixel values that are generally on the high end for the red, green, blue, and infrared spectral bands.  Docks also have contextual properties that can be used for identification, such as shape, texture, or proximity to shore.  This information can be categorized by a user and stored as ‘rules’ that a computer can implement to identify structures within a raw image.  The resulting data layer can then be used to develop models to understand the effects on aquatic organisms.

Where the magic happens.

The development of automated image classification techniques to better understand mechanisms of biological response is one aspect of my dissertation work that illustrates my interpretation of a broadly defined legal mandate.  Returning to my basic premise, I still consider myself challenged when asked to describe my current research interests (if you’ve read this far, you understand what I mean).  Describing my interests in a more succinct statement requires an instantaneous and undoubtedly subjective assessment of an individual’s background level of knowledge within which the answer can be framed.  That’s not to say that what I do is overly complicated, but to establish an understanding that my work has importance to different perspectives is an entirely different dilemma.  After all, why should we dedicate our careers to the pursuit of knowledge if we can’t convince others of the reasons why we believe doing so is important?  You may or may not be convinced that what I do has importance.  If you’re of the former opinion, then I’ve done my job, if you’re of the latter, then I haven’t.  I’ll let you be the judge.

About the Author:

Marcus Beck is a 2nd year PhD student and fourth year graduate student in the Conservation Biology program, Fisheries and Aquatic Biology track, with a minor in Statistics.  He is co-advised by Dr. Bruce Vondracek and Dr. Lorin Hatch.  His dissertation project is on developing quantitative tools to facilitate the use of biological indices in water quality programs, with a focus on ecological informatics.

Book Review: The Rivers of Minnesota by Thomas F. Waters

by George R. Spangler, Phd

River Eternal

Watching and feeling the extremes of seasonal changes in Minnesota are hallmarks of living in mid-continental North America. These include a landscape going from bare ground and mineral soil to croplands luxuriant with leaf and flower; temperatures ranging from -30° to 105°F; and, rivers brown and angry in draining the land from snowmelt and cloudbursts, or clear and serene in meandering to the Gulf. The constant in this is perpetuity itself with the orbit of the earth imposing adjustments on its surface, and by all who live here.  The wonder is that so much can be accomplished in so little time, a single revolution about our nearest star.

The distillation apparatus linking the sun’s heat to our rivers’ currents moves millions of tons of water through the atmosphere, onto the watersheds, into the groundwater, and back into the atmosphere about 75 times within a typical human lifespan. Fortunately, at least a few humans have taken the trouble to observe and record for the rest of us the pulse and patterns of distribution of this immense flow of water.

Thomas F. Waters (we can only applaud the juxtaposition of surname and subject here) has just completed his fifth full-length treatise on the magical and often lyrical movement of water across the landscape. “The Rivers of Minnesota” is a comfortable blending of geography and ecology and our human trysts with recreation and conservation in the North Star state.  Opening with a stimulating Foreword by the late Tom Helgeson, a writer long known to midwestern fishers, and preceding the dedication, is Riversong, a poem as gentle as the waters it describes.  Throughout the remaining 400 pages, chapter after chapter reverberate with the song of moving waters and the spirit of the writer whose own life has been so intimately intertwined with streams and rivers.  Readers will appreciate the respect he has shown them in not revealing too much, that they might encounter their own mysteries in traveling the myriad waters of the state, with fishing rod or paddle in hand.

Visit Dr. Spangler’s blog for more aquatic-ly inspired commentary.

About the author:

George Spangler is a Professor Emeritus in the Department of Fisheries, Wildlife, and Conservation Biology at the University of Minnesota. He was raised in California’s north  Sacramento Valley and graduated from Humboldt State University (B.S.), University of Toronto (M.S. and Ph.D.). He worked 10 years for the Ontario Ministry of Natural Resources on Lake Huron fisheries research before arriving to the University of Minnesota, where he taught classes including fish population dynamics, fisheries science and treaty rights for 30 years. Now retired in the Driftless Region at Preston, Minnesota, Dr. Spangler is Co-chair of the National Trout Learning Center.

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