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Responses Under Pressure

March 11th, 2010

As some of the broader impacts of the cultivation of biofuel feedstocks have become more apparent–not just the direct effects on greenhouse gas emissions but also indirect effects triggered by changes in the supply of agricultural commodities–so has the need to accurately estimate them. The assessment of the greenhouse gas emissions expected to flow from such induced land-use change (e.g., when farmers in Central America cut down forests to grow crops to replace the reduction in maize availability) has become a policy battleground.

The stakes are high: The 2007 Energy Independence and Security Act mandates a steep increase in the production of biofuels over the next dozen years, and requires estimates of life-cycle emissions of greenhouse gases from biofuels to be considered when establishing crucial definitions used for enforcement. The Environmental Protection Agency is currently wrestling with these definitions for a final rulemaking on new renewable fuel standards. Moreover, the California Air Resources Board has set rules that explicitly require the effects of indirect land-use change to be considered in establishing changes to its renewable fuel standards.

Because ethanol from maize accounts for almost all US biofuel production, assessments of its life-cycle greenhouse gas emissions drive the maelstrom. Tensions were only exacerbated by Timothy Searchinger and colleagues’ publication in 2008 of a calculation suggesting that, once global indirect land-use changes are counted, production of corn ethanol led to greenhouse gas emissions twice as large as those from burning gasoline; using switchgrass as a feedstock instead still increased total emissions. So much for green biofuels.

The Forum article by Thomas W. Hertel and coauthors that starts on p. 223 attempts to refine estimates of net greenhouse gas emissions resulting from the mandated increase in biofuel production. Its methodology, based on an equilibrium economic model that estimates market responses to changes in crop availability in different regions of the world, yields results only somewhat less alarming than those of Searchinger. The new estimate should be little comfort to ethanol manufacturers, or to anyone who would use prime agricultural land for fuel production. Hertel and colleagues write that their estimate is “enough to cancel out the benefits that corn ethanol has on global warming.”

The article is a valiant attempt at cross-fertilizing biology and economics to get the measure of a globally important effect of US policy, and as such deserves widespread attention. Hertel and his coauthors do their best to test the stability of their assessment, and it seems likely that others will build on their approach. It suggests a possible route for ecologists to get a grip on human responses to other sorts of environmental pressure.

Yet the article also reminds the reader of the numerous uncertainties surrounding attempts to model human behavior, and the difficulty of framing the real-world boundaries of such an analysis–obstacles Hertel and his coauthors acknowledge. The unexpected can be expected, and when it arrives, econometric studies will have to be redone. Still, a combination of biology and economics seems a more reliable guide to the future than would be either discipline alone.

Timothy M. Beardsley
Editor in Chief

BioScience 60: 167
doi:10.1525/bio.2010.60.3.1

Broadening Biology

February 1st, 2010

Those of us who once learned that genes are entities that propagate and manifest themselves within species may find their conceptual categories stretched beyond the breaking point if they dare read the overview of progress in metagenomics on page 102 by W. Ford Doolittle and Olga Zhaxybayeva. Together with the similarly challenging Feature by Karen Hopkin published in December (BioScience 59: 928-931), their article reminds us, if reminding were needed, that there is still a great deal still to be understood about how and where, exactly, natural selection acts on DNA. Critical analysis of new data makes clear that, among the bacteria and archaea that are Doolittle and Zhaxybayeva’s focus, the concept of species may hamper the appreciation of more fundamental categories: communities of interacting genes. Moreover, as Hopkin explained, the functioning of genes is not as straightforward as it once appeared. At least in eukaryotes, it is becoming more difficult to define precisely what a “gene” is. And as if this iconoclasm were not enough, biologists are becoming more aware of the importance for evolution of processes that do not principally involve heritable variations in DNA sequences.

Advancing insights into the complexity of life processes do not take anything away from the truths that previous generations of biologists have established. The colors of crossed pea plants can still be predicted using the laws of segregation and independent assortment, and innumerable experiments have confirmed the value of principles of population genetics established a century ago. But Gregor Mendel, G. H. Hardy, and Wilhelm Weinberg considered carefully selected cases amenable to analysis with the tools they had available. It is unsurprising that today, with vastly more powerful tools, we can see realities they could scarcely have been aware of. A sort of selection process will doubtless determine how useful some older concepts will remain.

It’s fascinating to consider the extent to which the biologists of the next century, or for that matter, of the coming decade, will rely on ideas familiar today. It would be arrogant to suppose that they will find them sufficient. It would likewise be arrogant to imagine that better understanding will make evolution in the real world predictable in detail. There are good reasons to believe that will remain impossible, which may be comforting to those who fear science’s influence. Yet the most basic biological insight of all–that repeated, controlled experiments can elucidate comprehensible and general mechanisms that constitute life–has come through with flying colors. The understanding of life is deepening, not disintegrating, and explanation is not going out of style, despite the attempts of evolution-deniers to muddy the waters. People who want to see science contribute to solving escalating environmental problems can be grateful: the enlightenment is not repealed. The potential for biology to help has never been greater.

Timothy M. Beardsley
Editor in Chief

BioScience 60: 91
doi:10.1525/bio.2010.60.2.1

Original post:
Broadening Biology

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Posted in Bioscience Reports

Tags: a-century-ago- a-makes-clear article tools

Refining the Biologist’s Sense of Identity

January 1st, 2010

While the biological sciences cover a broad terrain of ideas and subjects, we who explore that terrain have always defined ourselves as biologists. We might include an adjective that clarifies the level at which we study (e.g., molecular biologist) or the methods with which we’re most comfortable (e.g., mathematical biologist), but the noun has always been “biologist.”

Over the years, the number of adjectives has grown—we now have, among others, computational biologists, structural biologists, and systems biologists—and the definition of “biologist” has become ever broader, as has the range of background and expertise applied to research in biology. This dynamism and the progress it has catalyzed have inspired a new report from the National Research Council titled A New Biology for the 21st Century. As was noted in this space last November (http://caliber.ucpress.net/doi/full/10.1525/bio.2009.59.10.1), the report calls for an increased effort to nurture collaborations among different types of scientists who study living systems, defining the “New Biology” as the “reintegration of the subdisciplines of biology and integration into biology of physicists, chemists, computer scientists, engineers, and mathematicians.”

The report will inspire a range of reactions among biologists. Some of us may be
uneasy with the report’s subtle urging of biology to become more like engineering. And some of us may roll our eyes, because the New Biology is already upon us in so many arenas, from collaborations at the various synthesis centers to the range of
author expertise in a typical journal issue.

But we should set any such reservations aside and embrace this report. For one reason, the report supports the reintegration of our subdisciplines; if we believe in the noun, “biologist,” we surely believe that integration of our adjectival knowledge is important. For another reason, to advance the New Biology, the report urges a set of life-science research missions that is catholic in its breadth and vital in its importance to society. We surely want to support a clarion call for a substantially increased investment in fundamental life science and its applications.

The report does test our sense of identity, because in the New Biology, almost anyone can be a biologist. This calls us to focus on what that noun means. In particular, it asks us to balance the noun and our many adjectives. In practical terms, the challenge in both research and training is balancing depth in a specialty—how much emphasis to give the adjective—against breadth of understanding—how solid to make the noun.

This challenge is not really new, and AIBS has long been immersed in helping biologists answer it (witness its pioneering role in helping to develop the National Ecological Observatory Network—a massive research and educational effort that exemplifies the New Biology). AIBS, through its member societies, includes a very wide range of biologists and is the organization best suited to help advance the New Biology. During this year, I hope to bolster this effort, keeping more focus on the noun and less on this “newest” adjective. After all, when it comes to a passion for studying living systems, we are all biologists.

Joseph Travis
President, AIBS

BioScience 60: 3
doi:10.1525/bio.2010.60.1.1

Originally posted here:
Refining the Biologist’s Sense of Identity

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Eradicating Ignorance

December 1st, 2009

Sometimes scientists despair at the challenge of expanding the public’s understanding of science. Progress, however, is tangible, and one telling example last summer revolved around arthropods. In July, at the request of the US Department of Agriculture’s Animal and Plant Health Inspection Service (USDA APHIS), the National Research Council (NRC), the operating arm of the National Academies, convened a committee charged with evaluating APHIS’s response to two petitions filed by groups of citizens in California. The petitions opposed the agency’s decision to classify the light brown apple moth (LBAM; Epiphyas postvittana), a species native to Australia, as a quarantine-significant pest.

The moth’s presence in California was confirmed in 2007. In view of its reportedly broad host range—it infests numerous fruit crops, ornamentals, vegetables, and other economically important plants—APHIS classified the LBAM as “actionable” and “quarantine significant,” and immediately initiated a program of quarantine and eradication. Petitioners contended that the LBAM is not demonstrably a pest of economic importance and is already too widespread to be eradicated, and thus should be declassified. They were unhappy with areawide spraying, even of pheromones, and argued for alternative management approaches. APHIS asked the NRC to provide a critical assessment of the science used to reach and defend its action.

Just as the NRC committee (which I chaired) was preparing its report, Making
Catfish Bait out of Government Boys: The Fight against Cattle Ticks and the Transformation of the Yeoman South (University of Georgia Press, 2009) was published. The book’s author, Claire Strom, described another federal arthropod eradication campaign launched a century earlier. In 1906, the USDA’s Bureau of Animal Industry (BAI) implemented a program to eradicate the southern cattle tick from the United States in an effort to control babesiosis (Texas fever), a devastating protozoan disease of cattle vectored by the ticks. Then, as now, some citizens resented the program and questioned its feasibility. Although petitions were filed, these were mostly ignored. Some disgruntled citizens took another approach, dynamiting vats of cattle dip and, in the piney woods of Georgia, blowing away a 19-year-old BAI inspector with a shotgun blast.

Despite the violence, the program continued, and complete eradication (save for a small population in Florida) was proclaimed in 1943. The fate of the LBAM eradication effort is still undecided. However, the committee’s report (www.nap.edu/catalog.php?record_id=12762) recommended that APHIS provide a more robust scientific basis for its actions and articulate its justification more effectively.

Today’s citizens still have access to firearms, but they also have unprecedented
access to scientific information. It is to everyone’s benefit that sound science be seen as the more persuasive tool, and the scientific community must ensure that information accessible to the public is also comprehensible. Effective communication is paramount in determining the outcome of any scientific dispute. As the Year of Public Understanding of Science draws to a close, the need for a well-informed, scientifically literate public has not diminished; let’s hope that this is just the beginning of the Century of Public Understanding of Science.

May R. Berenbaum
President, AIBS

BioScience 59: 923
doi:10.1525/bio.2009.59.11.1