Subdiscipline Of Biology Research Articles

Taxonomy and phylogenetics: Some considerations

The relationships between taxonomy and phylogenetics are discussed. It is suggested that they are distinct biological subdisciplines and some consequences of this position are set out.

Species delimitation in lemurs: multiple genetic loci reveal low levels of species diversity in the genus Cheirogaleus.

BackgroundSpecies are viewed as the fundamental unit in most subdisciplines of biology. To conservationists this unit represents the currency for global biodiversity assessments. Even though Madagascar belongs to one of the top eight biodiversity hotspots of the world, the taxonomy of its charismatic lemuriform primates is not stable. Within the last 25 years, the number of described lemur species has more than doubled, with many newly described species identified among the nocturnal and small-bodied cheirogaleids. Here, we characterize the diversity of the dwarf lemurs (genus Cheirogaleus) and assess the status of the seven described species, based on phylogenetic and population genetic analysis of mtDNA (cytb + cox2) and three nuclear markers (adora3, fiba and vWF).ResultsThis study identified three distinct evolutionary lineages within the genus Cheirogaleus. Population genetic cluster analyses revealed a further layer of population divergence with six distinct genotypic clusters.ConclusionBased on the general metapopulation lineage concept and multiple concordant data sets, we identify three exclusive groups of dwarf lemur populations that correspond to three of the seven named species: C. major, C. medius and C. crossleyi. These three species were found to be genealogically exclusive in both mtDNA and nDNA loci and are morphologically distinguishable. The molecular and morphometric data indicate that C. adipicaudatus and C. ravus are synonymous with C. medius and C. major, respectively. Cheirogaleus sibreei falls into the C. medius mtDNA clade, but in morphological analyses the membership is not clearly resolved. We do not have sufficient data to assess the status of C. minusculus. Although additional patterns of population differentiation are evident, there are no clear subdivisions that would warrant additional specific status. We propose that ecological and more geographic data should be collected to confirm these results.

Citations

Citations

Keith Douglass Warner, Agroecology in Action: Extending Alternative Agriculture Through Social Networks

In Agroecology in Action, Keith Douglass Warner describes and analyzes a number of important agroecological partnerships in the United States, with a focus on partnerships in California. The work examines the actors involved in these partnerships, along with the networks formed, the practices espoused, and the successes achieved over the years of their development and existence. The book also provides an account of how a variety of new, ecologically based farming and pest control methods have been developed as a result of farmers, scientists, public agencies, and nongovernmental organizations working together to address the environmental impact of conventional, chemical intensive farming methods. Warner defines agroecological partnerships as ‘‘initiatives using alternative extension practices at the field scale’’ (5), highlighting how these partnerships rely heavily on nontraditional modes of generating and sharing knowledge and how the local knowledge of farmers, and considerations for local ecologies, form the backbone of these partnerships. Warner argues that agroecology ‘‘must be facilitated by social learning’’ (3), defined as a process whereby groups of varied stakeholders engage in experiential research and knowledge exchange to protect and enhance shared resources. Agroecological partnerships, and their methods of generating and sharing knowledge, are contrasted with traditional extension practices that have tended to utilize transfer of technology or adoption/diffusion paradigms. Citing Carson’s Silent Spring (1962), Warner sets the stage for examining agroecological partnerships by outlining not only the failures of industrial agriculture but the influence that Silent Spring had on reshaping farming practices and political and scientific institutions. Warner credits Carson for laying the foundation for modern day agroecological partnerships and for inspiring students of the 1960s and 1970s who later went on to develop the subdisciplines of agroecology and conservation biology. With this backdrop, Warner utilizes the works of Latour (1987, 1999) and FitzSimmons (2003) in the field of Science and Technology Studies to examine the critique of Silent Spring and the dynamics of both agroecology and science in general. As proposed by Latour, and later adapted by FitzSimmons, science can be viewed as a circulatory system, with a beating heart at its center, creating and pumping knowledge through four different loops. These loops represent nature, scientists, end-users, and the public, and are all bound together by scientific knowledge at the center. As Warner points out, Silent Spring critiqued the science of its time for only engaging scientists and enduser and neglecting the ecological and social consequences of the scientific knowledge it created and diffused. In contrast, agroecological partnerships, as examined throughout Agroecology in Action, repeatedly and consistently attempt to engage many actors in the farming and scientific system to produce appropriate knowledge to reduce environmental harm, manage risk, maintain profits for growers and address public concerns about pollution and pesticides in agriculture. The bulk of Agroecology in Action examines the intricacies of a number of commodity specific agroecological partnerships in California and beyond. These examinations, in turn, lead to analyses of the institutional opportunities and constraints for agroecological partnership development, factors that influence the reduction of pesticide use, the characteristics and roles of actors who participate in partnerships, the various agroecological practices promoted B. McKelvey (&) University of Missouri Extension, Columbia, MO 65211, USA e-mail: McKelveyWA@missouri.edu

Daphnia comes of age: an ecological model in the genomic era

Scientists in various subdisciplines of biology have long relied on model organisms to push the frontiers of knowledge forward as far as possible in their specific field. Today, interdisciplinary science requires model organisms that can push our understanding on multiple frontiers and help us formulate and address more complex questions. Members of the genus Daphnia represent just such an interdisciplinary model. Daphnia are aquatic microcrustaceans (also known as waterfleas) that have long been central to the study of ecology and toxicology and have recently been developed as a genomic model. A recent survey of both nuclear and mitochondrial markers in populations of the Daphnia pulex complex from high-altitude lakes in South America (Mergeay et al. 2008, this issue) provides an excellent example of how genetic data and ecological information can be used to push the boundaries of our understanding in molecular ecology. In this species complex, extensive hybridization has occurred resulting in polyploidization and, consequently, asexuality. Their data reveal high levels of genetic diversity, incongruence in phylogenetic signal among genomes (nuclear and mitochondrial), cryptic species in the complex, and a new model for the historical spread of the species throughout the Americas. Their data indicate that genome-level changes have occurred in this species which have profound consequences in an ecological context, the implications of which can be more fully appreciated because of our extensive knowledge of the ecology and natural history of the genus Daphnia.

Focus: Issues in Developmental Biology Education

Welcome to this special focus section of CBE—Life Sciences Education. A large portion of this issue deals with aspects of teaching and learning in a particular subdiscipline of the life sciences: developmental biology. The field of developmental biology has progressed rapidly over the past two decades. The modern synthesis of molecular and genetic approaches in model organisms, comparative and evolutionary insights from genomics, use of increasingly sophisticated microscopy techniques, and application of this knowledge to human biology have thrust developmental biology to the forefront of not only science journals but also the public consciousness. A stream of recent Nobel prizes in Physiology or Medicine awarded for work in developmental biology attests to its importance as a central aspect of modern life science. Issues such as therapeutic and reproductive cloning and stem cell biology grab headlines. Clearly, thinking well about how to communicate the fundamental features of developmental biology to the students of today and tomorrow is important. This issue of CBE-LSE contributes to what we hope will be an increasing focus on developmental biology education in the twenty-first century. Given the ascendancy of developmental biology in the current era, several key questions arise: To what extent is developmental biology a field separate from cell biology? Is it, as one of my colleagues likes to say, simply “cell biology over time,” or is it a truly separate way of knowing, with its own educational challenges that are genuinely unique to the subject? Are there special visual and conceptual challenges in teaching developmental biology that distinguish it from other subdisciplines in biology? Given the inherent ethical ramifications of developmental biology applied to humans, to what extent should ethics be incorporated into majors science courses in developmental biology? The Points of View feature in this issue by Gilbert et al. addresses some of these issues. Given the public importance of developmental biology, another issue facing developmental biology instructors is that of increasing scientific literacy in this area. The interview with Morris Maduro by Hoopes and the articles by Gehring and Eastman and by Madhuri and Broussard deal with this issue. Anyone who has peered through a microscope at developing embryos cannot help but be struck by how arresting they are visually. The WWW feature by Stark, the article on teaching Caenorhabditis elegans lineage analysis by Lu et al., and the essay on using photomicrographs by Watson and Lom examine resources and methodologies for teaching this visual aspect of developmental biology. Finally, plant development is often left out of developmental biology discussions. The article by Spiro and Knisely provides one practical example of how to teach plant development. Other features, articles, and essays in previous issues of CBE-LSE have also dealt with the teaching and learning of developmental biology, including the following: WWW Features by Robert Blystone and Dennis Liu Deformed amphibian research at Hartwick College [CBE-LSE 2(2003): 14–15; http://www.lifescied.org/cgi/content/full/2/1/14#SEC1] C. elegans movies [CBE-LSE 2(2003): 14–15; http://www.lifescied.org/cgi/content/full/2/1/14#SEC2] Potent cells [CBE-LSE 6(2007): 90–94; http://www.lifescied.org/cgi/content/full/6/2/90] Video Views and Reviews by Christopher Watters Mitosis and early development [CBE-LSE 1(2002): 111–114; http://www.lifescied.org/cgi/content/full/1/4/111#SEC3] Angiogenesis (the development of blood vessels) [CBE-LSE 2(2003): 9–13; http://www.lifescied.org/cgi/content/full/2/1/9#SEC4] Cytokinesis: a phenomenon overlooked too often [CBE-LSE 4(2005): 10–18; http://www.lifescied.org/cgi/content/full/4/1/10#SEC1] Gastrulation [CBE-LSE 4(2005): 273–278; http://www.lifescied.org/cgi/content/full/4/4/273] Neurulation and the fashioning of the vertebrate central nervous system [CBE-LSE 5(2006): 99–103; http://www.lifescied.org/cgi/content/full/5/2/99] Book Reviews Fink, R. D. A shelf of stem cells [CBE-LSE 3(2004): 20–21; http://www.lifescied.org/cgi/content/full/3/1/20] Vasquez, J. From genes to embryo and beyond [CBE-LSE 6(2007): 27–28; http://www.lifescied.org/cgi/content/full/6/1/27] Articles and Essays Fink, R. Cloning, stem cells, and the current national debate: incorporating ethics into a large introductory biology course [CBE-LSE 1(2002): 132–144; http://www.lifescied.org/cgi/content/full/1/4/132] Gilat Brill, G., and Yarden, A. Learning biology through research papers: a stimulus for question-asking by high-school students [CBE-LSE 2(2003): 266–274; http://www.lifescied.org/cgi/content/full/2/4/266] Knight, J. K., and Wood, W. B. Teaching more by lecturing less [CBE-LSE 4(2005): 298–310; http://www.lifescied.org/cgi/content/full/4/4/298] Lu, F.-M. et al. WormClassroom.org: an inquiry-rich educational web portal for research resources of Caenorhabditis elegans [CBE-LSE 6(2007): 98–108; http://www.lifescied.org/cgi/content/full/6/2/98] Salli, U. et al. Stem cell biology should be taught in high schools [CBE-LSE 6(2007): 283–284; http://www.lifescied.org/cgi/content/full/6/4/283] We hope you enjoy this focus on issues in developmental biology education, and we welcome your suggestions regarding other potential special topics for future issues of CBE-LSE.

The Necessity of Making Visible Concepts with Multiple Meanings in Science Education: The Use of the Gene Concept in a Biology Textbook

The purpose of this study is to analyze variations in how the gene concept is used and conceived in different sub-disciplines in biology. An examination of the development of subject matter and the use of the gene concept in a common college biology textbook shows that the gene concept is far from presented in a consistent way. The study describes and categorizes five different gene concepts used in the textbook; the gene as a trait, an information-structure, an actor, a regulator and a marker. These conceptual differences are not dealt with in an explicit manner. This constitutes one of the sources for confusion when learning about genes and genetics.

Teaching without a Textbook: Strategies to Focus Learning on Fundamental Concepts and Scientific Process

Textbooks are ubiquitous. They are available for almost every conceivable subdiscipline of biology, and few of us would consider teaching a course without using a textbook. Over the years, they have become more colorful, more encyclopedic, and accompanied by more ancillary materials such as CD-ROMs, study guides, and websites. With all these tools to assist our students, it seems reasonable that they are able to learn more and better than ever. Thus, the question most instructors ask themselves is most likely which textbook to use, not whether to use a textbook. But does the use of textbooks really help students learn better? In this Point of View, I invited a commentary on this question from a faculty member who has decided to abandon the use of a textbook in an introductory level cell and molecular biology course.

Squaraine Rotaxanes: Superior Substitutes for Cy‐5 in Molecular Probes for Near‐Infrared Fluorescence Cell Imaging

Recent breakthroughs in fluorescence microscopy are producing notable improvements in imaging resolution.[ 1 ] These ongoing technical advances should have a major positive impact on the emerging field of cell imaging using single molecule methods, and help merge the sub-disciplines of cell and molecular biology.[2] However, the full potential of many of these new high-resolution imaging methods will only be achieved if they employ extremely bright and highly stable luminescent probes that do not undergo photobleaching or photoblinking.

Migrating Ovaries: Early Life Influences on Later Gonadal Function

Progress in the biomedical and clinical sciences has relied heavily on experimental animal research. However, the impact of other comparative disciplines such as evolutionary biology, and in particular its subdisciplines of life history biology and ecological developmental biology, on human medicine has been limited. Despite its heritage and contributions, evolutionary biology has rarely been applied to understanding human development, particularly from a medical rather than an anthropological perspective.

On the Role of Physics in the Growth and Pattern Formation of Multi-Cellular Systems: What can we Learn from Individual-Cell Based Models?

We demonstrate that many collective phenomena in multi-cellular systems can be explained by models in which cells, despite their complexity, are represented as simple particles which are parameterized mainly by their physical properties. We mainly focus on two examples that nevertheless span a wide range of biological sub-disciplines: Unstructured cell populations growing in cell culture and growing cell layers in early animal development. While cultured unstructured cell populations would apriori been classified as particularly suited for a biophysical approach since the degree to which they are committed to a genetic program is expected to be modest, early animal development would be expected to mark the other extreme—here the degree of determinism according to a genetic program would be expected to be very high. We consider a number of phenomena such as the growth kinetics and spatial structure formation of monolayers and multicellular spheroids, the effect of the presence of another cell type surrounding the growing cell population, the effect of mutations and the critical surface dynamics of monolayers. Different from unstructured cell populations, cells in early development and at tissue interfaces usually form highly organized structures. An example are tissue layers. Under certain circumstances such layers are observed to fold. We show that folding pattern again can largely be explained by physical mechanisms either by a buckling instability or active cell shape changes. The paper combines new and published material and aims at an overview of a wide range of physical aspects in unstructured populations and growing tissue layers.

Biological stress response terminology: Integrating the concepts of adaptive response and preconditioning stress within a hormetic dose–response framework

Many biological subdisciplines that regularly assess dose–response relationships have identified an evolutionarily conserved process in which a low dose of a stressful stimulus activates an adaptive response that increases the resistance of the cell or organism to a moderate to severe level of stress. Due to a lack of frequent interaction among scientists in these many areas, there has emerged a broad range of terms that describe such dose–response relationships. This situation has become problematic because the different terms describe a family of similar biological responses (e.g., adaptive response, preconditioning, hormesis), adversely affecting interdisciplinary communication, and possibly even obscuring generalizable features and central biological concepts. With support from scientists in a broad range of disciplines, this article offers a set of recommendations we believe can achieve greater conceptual harmony in dose–response terminology, as well as better understanding and communication across the broad spectrum of biological disciplines.

Towards a unified science of cultural evolution

We suggest that human culture exhibits key Darwinian evolutionary properties, and argue that the structure of a science of cultural evolution should share fundamental features with the structure of the science of biological evolution. This latter claim is tested by outlining the methods and approaches employed by the principal subdisciplines of evolutionary biology and assessing whether there is an existing or potential corresponding approach to the study of cultural evolution. Existing approaches within anthropology and archaeology demonstrate a good match with the macroevolutionary methods of systematics, paleobiology, and biogeography, whereas mathematical models derived from population genetics have been successfully developed to study cultural microevolution. Much potential exists for experimental simulations and field studies of cultural microevolution, where there are opportunities to borrow further methods and hypotheses from biology. Potential also exists for the cultural equivalent of molecular genetics in "social cognitive neuroscience," although many fundamental issues have yet to be resolved. It is argued that studying culture within a unifying evolutionary framework has the potential to integrate a number of separate disciplines within the social sciences.

Announcements

Announcements

Recapitulating the History of Sickle-Cell Anemia Research

This paper provides an argument in favor of a specific pedagogical method of using the history of science to help students develop more informed views about nature of science (NOS) issues. The paper describes a series of lesson plans devoted to encouraging students to engage, unbeknownst to them, in similar reasoning that led scientists to understand sickle-cell anemia from the perspective of multiple subdisciplines in biology. Students pursue their understanding of a ‘mystery disease’ by means of a series of open-ended problems that invite them to discuss it from the perspective of anatomy, physiology, ecology, evolution, and molecular and cell biology. Throughout this unit, instructors incorporate techniques that invite students to explicitly and reflectively discuss various NOS issues with reference to this example and more generally. It is argued on the grounds of constructivist tenets that this pedagogy has substantial advantages over more implicit approaches. The findings of an empirical study using an open-ended survey and follow-up, semi-structured interviews to assess students’ pre- and post-instruction NOS conceptions support the efficacy of this approach.

Points of View: A Survey of Survey Courses: Are They Effective?

Points of View: A Survey of Survey Courses: Are They Effective?

Systematics and the future of biology

B iology is a science of three dimensions. The first is the study of each species across all levels of biological organization, molecule to cell to organism to population to ecosystem. The second dimension is the diversity of all species in the biosphere. The third dimension is the history of each species in turn, comprising both its genetic evolution and the environmental change that drove the evolution. Biology, by growing in all three dimensions, is progressing toward unification and will continue to do so. A large part of the future of biology depends on interdisciplinary studies that allow easy travel across the three dimensions. Molecular and cellular biology, the subdisciplines of maximum support and activity today, occupy the two lowest levels of biological organization. They are focused on the first dimension in a small set of model species, selected primarily for their ease of culturing and the special traits that make them amenable for different kinds of analysis. The triumph of molecular and cellular biology has been the documentation of one of the two overarching principles of biology: that all living phenomena are obedient to the laws of physics and chemistry. The other overarching principle of biology is that all living phenomena originated and evolved by natural selection. That, in turn, has been the triumph of organismic and evolutionary biology. Viewed in the framework of the history of biology, the subdisciplines of molecular and cellular biology are in the natural history period of their development. This perhaps surprising characterization can be clarified with the following metaphor. The cell is a system consisting of a very large number of interacting elements and processes. It can be compared to a conventional ecosystem, such as a lake or forest, in this sense: Researchers …

IS LESS MORE?1

With the blossoming of evolutionary developmental biology and evolutionary genomics following on the heels of the recent molecular revolution in evolutionary biology, the field is arguably expansive and integrative than ever. This growth has infused an air of excitement and anticipation into the discipline, as it appears to be on the verge of providing long-awaited answers to questions such as the structure of the tree of life, the origin of body plans, the genetic changes that underlie speciation, and the genetic basis of those traits that make us uniquely human (Avise 2003; Coyne and Orr 2004; Carroll 2005; The Chimpanzee Sequencing and Analysis Consortium 2005). At the same time, the fact that the pageantry of research in evolutionary biology is so diverse presents vexing questions for those of us faced with teaching undergraduate courses in evolutionary biology: how much of this vast discipline should we attempt to cover in a single course, and what is the best way to organize the material? The question of how much to cover is certainly not unique to evolutionary biology. Indeed, recent examples of streamlined textbooks for other survey courses such as ecology (e.g., Molles 2005), genetics (e.g., Hartl and Jones 2006), and general biology (e.g., Cain et al. 2006), suggests a growing sense that biology students in general may be best served under a less is more model of education. It is debatable whether this trend is motivated by the impracticalities of squeezing a rapidly expanding discipline into a single course, or by the reality of facing students who are poorly prepared for college science courses. However, one additional contributing factor is certain; most students in an upper level survey course in biology have no intention of pursuing a career in that biological subdiscipline. Thus, only a small fraction of students in such a course hunger for the subtle nuances of the field. As instructors, it is clear that these self-motivated students do not present our greatest educational challenge. Rather, our challenge in survey courses, including evolutionary biology, is in helping the uninspired majority learn both the central concepts and the ways of approaching questions in the major fields in biology. Given that challenge, it is difficult to argue against the less-is-more philosophy. Ironically though, it is probably safe to say that the majority of those who currently teach undergraduate courses in evolutionary biology cut their eye teeth while chewing (figuratively, one hopes) on the famously dense, exhaustively integrative, and encyclopedic Evolutionary Biology (Futuyma 1979, and subsequent editions). But while such a textbook provided abundant inspiration for students destined to become evolutionary biologists, its very strengths made it a

Promoting a Tinbergian Approach to Animal Behaviour.

Promoting Tinbergian Approach to Animal Behaviour Review of The Behavior of Animals: Mechanisms, Function, and Evolution, Johan J. Bolhuis and Luc-Alain Giraldeau (Eds.) (Maiden, MA, Oxford, UK, Carlton, Australia: Blackwell Publishing, 2004), 515 pages) This edited volume is meant as a comprehensive textbook on animal behavior (from the Preface by the editors, p. xvii). The Preface states two main aims: 1) to incorporate all the contemporary subdisciplines of behavioral biology, such as animal welfare, conservation biology, evolutionary psychology, animal cognition, and behavioral (p. xvii), and 2) to present perspectives on all four of Niko Tinbergen's classic (1963) whys of animal behaviour, namely about causation, development, function, and evolution (p. xvii). The result is collection of 17 chapters, each written by one or two experts on the topic, bound in paper and sprinkled with black-and-white figures and photographs. Tinbergen's four whys are featured in the beginning of number of contemporary single-authored textbooks on animal behaviour (Alcock, 2005; Barnard, 2004), but not all (Dugatkin, 2005). Of the four whys, proximate questions comprise the immediate conditions, both in the environment and in the organism, that trigger behaviour (mechanism) and the unfolding of behaviour over the course of an individual's life (development). Ultimate questions comprise the adaptive value of the behaviour (function) and the evolutionary history that led to the behaviour (evolution). The editors set out to give emphasis to both proximate and ultimate questions, in different sections of the book. I, Mechanisms of Behavior topics and discipines with mechanistic bent. It includes chapters on stimulus perception (J-P- Ewert, neuroethological perspective), motivation (J. A. Hogan), biological rhythms (R. E. Mistlberger & B. Rusak), behavioural neuroscience (D. F. Sherry), development Q. J. Bolhuis), animal learning (K. Kirkpatrick & G. Hall), and animal cognition (N. J. Emery & N. S. Clayton). II, Function and Evolution of Behavior features chapters on function (L.-A. Giraldeau), communication (P. K. McGregor), sex and mating (two chapters, the other by A. P. M011er, one by M. A. Elgar), and sociality (A. E. Pusey). III, Animal Behavior and Human Society comprises three chapters on topics of concern to humans, on animal welfare (D. Fraser & D. M. Weary), conservation (T. Caro & J. Eadie), and evolutionary psychology (M. DaIy & M. Wilson), which is the attempt to provide evolutionary explanations of human behaviour. Thus, while animal welfare and conservation do not fit comfortably into Tinbergian framework, the chapter on human behaviour is squarely evolutionary in outlook, and can fit into Part II. Textbooks that feature human behaviour, however, typically place the chapter at the end (Alcock, 2005; Barnard, 2004). How do the individual chapters fare? As with most collected volumes, the tone, style, density of content, and quality vary. Some chapters present topics at great depth. Thus, Jorg-Peter Ewert's chapter on stimulus perception present visual mechanisms, including much of Ewert's own work, in great depth. I rate this level of depth too much for an introductory text on animal behaviour. This depth means that little else is covered, and many fascinating and unusual perceptual capabilites are neglected, including the echolocation of bats, the tactile capabilities of the star-nosed mole, the perception of polarized light by insects, and magnetoperception in sea turtles, to name some exotic cases found in Alcock's latest (2005) edition. Some sense of the Umwelt created by these modes of perception is good to convey, as they differ, sometimes starkly, from the human perceptual world. Some chapters present manytopics superficially. Thus, Jerry Hogan's chapter on motivation whips through systems of hunger, parenting, aggression, sex, self-maintenance (grooming), sleep, and fear at around page piece. …

CAUTION: NICHE CONSTRUCTION AHEAD1

This fall, I watched as my neighbors waged war on moles (to be fair, it was the wife's mother and aunt, who became known as the It seems the moles were suspected as weapons-of-grass-destruction and were deemed to be dangerous to the way of life of free lawns everywhere. The mole patrol roamed the lawn each evening, pouring all manner of organic and inorganic chemical warfare into the burrows of the unsuspecting moles, setting up conventional implements of physical torture in mole runs, and finally chasing moving tunnels with sharp sticks. To my knowledge, no single mole succumbed to this police action, though I did notice that some crossed borders into a more protective sovereignty and dug up my yard. Not really caring about some dirt mounds in my yard, I found myself instead thinking about the selective forces faced by suburban moles and how their actions modified the microhabitat in which they lived. I did not realize it then, but the moles and the mole patrol they brought down upon themselves through their burrowing behavior are examples of niche construction, wherein organisms modify their surroundings and in doing so, alter patterns of selection. The extended phenotype of the moles-the molehills they created-altered the action of potential predators (the mole patrol). In so doing, the moles indirectly affected the soil by causing a variety of chemical cocktails to be poured into the ground. Finally, they relocated to a new and less-challenging selective by moving into my yard. As defined by Odling-Smee, Laland, and Feldman, niche construction occurs an organism modifies the featurefactor relationship between itself and its by actively changing one or more of the factors in its environment (p. 41). The authors cast a broad net that encompasses such a diversity of biological phenomena that it is hard to imagine a subdiscipline of biology that would not be touched by this concept. As summarized in a lengthy chapter on the evidence for niche construction, virtually all beings, live or dead, fit this broad criterion. Any living organism alters its environment, whether it be as simple and passive as a plant altering the wavelengths of light experienced by itself and others through reflection off of and transmission through its leaves, or as dramatic as the pond habitat created by beavers when they dam a stream. A predator that moves to a new foraging locality when food becomes scarce constructs its niche by relocating and thereby changing the selection it experiences. The mere act of respiration alters the mixture of gases experienced by other organisms in the community. Ironically,