Evolutionary Biology: Limits to Knowledge in Evolutionary Genetics: 32

Making evolutionary biology a basic science for medicine

As noted at the outset, we live in an exciting time for evolutionary biology. The study of evolution, which in the past was often equated with changes in gene frequencies in populations, has become more holistic and integrative. Researchers are increasingly interested in exploring how interactions among genes, individuals, and environments have shaped the evolutionary process, both at micro- and macrolevels. At the same time, large challenges such as global warming, novel infectious diseases, and threats to biodiversity are increasing, and the opportunity for evolutionary biologists to contribute to their resolution has never been greater.

Realizing the full potential inherent in evolutionary biology is, however, far from assured. The task of integrating evolutionary knowledge within and across scales of biological organization, as discussed above, requires development of many comparative databases and analytical tools. We would do well to collaborate broadly, cultivating new expertise, and to watch out for the unexpected, as analyses of new kinds of data can reveal that preconceptions are unfounded.

Encyclopedia of Evolutionary Biology | ScienceDirect

Because most of our science is supported by limited public funds, evolutionary biologists and ecologists should support and participate in efforts to help the public understand the issues and the value of scientific understanding. Science in general and evolutionary science in particular are often politicized, exactly because of their fundamental importance to human society. The next 20 years hold the promise of a golden age for evolutionary biology.

Whether we realize that promise depends in part on how effectively we communicate that message. Cyberinfrastructure —The research environments that support advanced data acquisition, data storage, data management, data integration, data mining, data visualization, and other computing and information processing services distributed over the Internet beyond the scope of a single institution. In scientific usage, cyberinfrastructure is a technological solution to the problem of efficiently connecting laboratories, data, computers, and people.

Evolutionary developmental biology —The study of the evolution of development, often by the comparative study of gene expression patterns through the course of development in different species. Gene network —A flow diagram describing the interactions among genes during development that affect a particular phenotype or set of phenotypes.

Genomics —The study of the entire complement of DNA in organisms Genome , including is sequence and organization. GMO —Genetically modified organisms in which the genome has been deliberately changed; transgenic organisms resulting from DNA manipulations. Lateral horizontal gene transfer —Genetic transfer between species, as opposed to vertical gene transmission from parents to offspring in a lineage.

Metadata —Data associated with individual DNA sequences or organismal specimens e. Model organism —Organisms whose genome has been sequenced and for which sophisticated tools for genetic manipulation are available. Natural history —The entire description of an organism, including its phenotype, genome, and ecological context i.

Ontology —The naming of categories, especially of the functions of genes. Population genetics —The study of the evolutionary forces that change the genetic composition of a population; the discipline is often concerned with evolution at one or a few genetic loci. Quantitative genetics —The study of the inheritance and evolution of traits that are typically affected by many genetic loci. Transgenic tools —Tools that enable the deliberate transfer of DNA sequences from one organism to another or the deletion or modification of DNA sequences, in every cell, in one organism.

Browse this book

An example of the enormous phylogenetic trees that soon will represent the norm in phylogenetic analyses. This is the consensus tree of the maximum likelihood phylogenies for 55, species of seed plants with the location of significant shifts in species diversification rates marked in red across the tree. The Phenomobile, a remote sensing field buggy, and the Blimp, for remotely imaging an entire field.

The Phenomobile integrates a variety of remote sensing technologies for measuring phenotypic variables on many plants simultaneously. The buggy straddles a plot and collects measurements of plant temperature, stress, chemistry, color, size and shape, as well as measures of senescence. The Blimp is designed to image all the plants in an entire field from a height of 30—80 m using both infrared and digital color cameras.

The workshop that led to this report was funded by the National Science Foundation. We thank the American Society of Naturalists, the Society for the Study of Evolution, and the Society of Systematic Biologists for organizational and planning assistance. Many thanks to Melissa Woolley for invaluable assistance with logistics and manuscript preparation and to M. Weirman for help procuring images. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

National Center for Biotechnology Information , U. Published online Jan 8. Arnold , 2 Gill Bejerano , 3 E. Hoekstra , 1 , 6 David P. Allen Orr , 11 Dmitri A. Petrov , 12 Susanne S. Renner , 13 Robert E. Ricklefs , 14 Pamela S. Soltis , 15 and Thomas L. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.

This article has been cited by other articles in PMC. Introduction We live in an exciting time for biology. Open in a separate window. Evolutionary biology is being transformed by increasing access to burgeoning data on variation in genomes, organisms, and the environment.

Introduction

Limits to Knowledge in Evolutionary Genetics. Series: Evolutionary Biology, Vol. Clegg, Michael T., Hecht, Max K., MacIntyre, Ross J. (Eds.) Price from. Part of the Evolutionary Biology book series (EBIO, volume 32) discussion I want to raise the question of whether there are limits to our knowledge of evolution.

Feeding the Human Population Feeding the rapidly growing human population, especially with increasing stress on agricultural systems from climate change, continues to be a major challenge. Sustaining Biological Diversity Evolutionary approaches have often been applied to the conservation of species and ecosystems [13] , [39] — [42]. Computation and Design Models of mutation, inheritance, and selection have inspired the development of computational evolutionary algorithms that are used to solve complex problems in many fields [53] , [54].

Evolution and Justice Genealogical relationships bear on many court cases. Emerging Research and Future Challenges in Evolutionary Biology Divining the direction of future scientific research is always fraught with difficulty. New Theory The flood of data in all areas of evolutionary biology poses important theoretical challenges: The Explosion and Diversity of Data DNA sequencing can now generate whole-genome data not only for single representatives of a few species but for multiple individuals from multiple conspecific populations and even from entire communities.

Natural history museum collections are tremendous repositories of specimens and data of many sorts, including phenotypes, tissue samples, vocal recordings, geographic distributions, parasites, and diet. Evolutionary Processes That Shape Genomic and Phenotypic Variation The availability of genomic data from a remarkable range of species has allowed the alignment and comparison of whole genomes. Earth—Biosphere Interactions Over Vast Stretches of Time and Space We are in the midst of a massive perturbation of natural communities as species respond to human-driven changes in climate and land cover.

Understanding Biological Diversification A major and urgent challenge is to improve knowledge of the identity and distribution of species globally. Developing genetic and evolutionary tools for taxa with an extensive fossil record will be an important means of integrating the study of evolutionary pattern and process. Logistical Issues and Opportunities To take full advantage of technological advances, especially the availability of new data types and databases, we must confront several challenges that involve community resources and how we use them.

Glossary Cyberinfrastructure —The research environments that support advanced data acquisition, data storage, data management, data integration, data mining, data visualization, and other computing and information processing services distributed over the Internet beyond the scope of a single institution. Evolutionary genetics —Population and quantitative genetics. Supporting Information Figure S1 An example of the enormous phylogenetic trees that soon will represent the norm in phylogenetic analyses. TIF Click here for additional data file. Figure S2 The Phenomobile, a remote sensing field buggy, and the Blimp, for remotely imaging an entire field.

Text S1 Training to sustain evolutionary biology. DOCX Click here for additional data file. Text S2 Infrastructure needs and opportunities in evolutionary biology. Acknowledgments The workshop that led to this report was funded by the National Science Foundation. Funding Statement The workshop that led to this report was funded by the National Science Foundation.

Wilson EO The future of life. Millennium Ecosystem Assessment Ecosystems and human well-being: Mindell DP The evolving world: Chivian E, Bernstein A Sustaining life: Held LI Jr Quirks of human anatomy: Trends Cogn Sci Oppenheimer S Out-of-Africa, the peopling of continents and islands: New applications of evolutionary biology in medicine are being discovered at an accelerating rate, but few physicians have sufficient educational background to use them fully.

This article summarizes suggestions from several groups that have considered how evolutionary biology can be useful in medicine, what physicians should learn about it, and when and how they should learn it. Our general conclusion is that evolutionary biology is a crucial basic science for medicine. In addition to looking at established evolutionary methods and topics, such as population genetics and pathogen evolution, we highlight questions about why natural selection leaves bodies vulnerable to disease. Knowledge about evolution provides physicians with an integrative framework that links otherwise disparate bits of knowledge.

It replaces the prevalent view of bodies as machines with a biological view of bodies shaped by evolutionary processes. Like other basic sciences, evolutionary biology needs to be taught both before and during medical school. Most introductory biology courses are insufficient to establish competency in evolutionary biology.

Premedical students need evolution courses, possibly ones that emphasize medically relevant aspects. In medical school, evolutionary biology should be taught as one of the basic medical sciences. This will require a course that reviews basic principles and specific medical applications, followed by an integrated presentation of evolutionary aspects that apply to each disease and organ system. Evolutionary biology is not just another topic vying for inclusion in the curriculum; it is an essential foundation for a biological understanding of health and disease.

New applications of evolutionary biology to medical problems are being discovered at an accelerating rate. This article considers what changes in medical education are needed to bring the full power of evolutionary biology to bear most quickly on human health problems.

For the sake of focus and simplicity, we address here only medical education; parallel educational recommendations will offer similar benefits in other health sciences, especially public health. Several sources contribute to the recent flowering of evolutionary approaches in medicine. Genetic variants carried by individuals who reproduce more than others tend to increase in frequency over the generations, thus shifting the genetic make-up and mean phenotype of the population to be more like them and generally better adapted to their environments.

The role of natural selection in shaping living organisms has been empirically confirmed beyond dispute.

Selection is by no means the only factor, however. Mutations are inevitable; DNA is damaged by radiation and toxins, and replication is not perfect.

1. The Nature of Evolution: Selection, Inheritance, and History

Other random events are also important; genetic drift can push neutral or even deleterious alleles to high frequency, whereas a storm might eliminate all individuals with a useful mutation. Population bottlenecks, inbreeding, and migrations also shape gene frequencies, which in turn influence the distribution of phenotypes. Natural selection and these other evolutionary mechanisms change species, and, equally important, keep them the same via stabilizing selection that disfavors individuals with extreme traits 2 , 3.

These core principles are, however, only the roots of a rapidly growing network of explanations based on evolution. One main branch is phylogeny. Long-established methods for analyzing relationships within and among species are now being augmented by new methods that use molecular genetic data to test hypotheses about the relationships among populations and species and about the large-scale history of life itself 4.

The other main branch is the study of adaptation. The unity of all life was only one of Darwin's greatest discoveries; the other was his explanation for why organisms have traits that are so well adapted to the challenges they face. No plan is involved; natural selection tends to increase the frequencies of alleles of individuals that survive and reproduce better than others in specific environments 5.

Sewall Wright 6 envisioned this process as a landscape of hills and valleys, where the hills represent peaks of fitness and the valleys regions of reduced fitness. Tinbergen 7 and Mayr 8 provided an important clarification of the difference between proximate questions about mechanisms and evolutionary questions about origins and functions.

Services on Demand

Coevolution and the complex interactions of ecosystems are important applications of the basic concepts. First, in terms of contents, the formation of teachers must include the identification of their previous conceptions, the conceptual change needed, and the update of that knowledge. Accessed May 25, The Blimp is designed to image all the plants in an entire field from a height of 30—80 m using both infrared and digital color cameras. Perlman , Mark D.

For instance, the proximate explanation of the adrenal gland includes its anatomy, tissues, chemical constituents, and the developmental processes that assemble them. Separate, and equally important, is an evolutionary explanation: Notice that each kind of question has two subquestions. What is the mechanism? How did the mechanism develop? How has it given a selective advantage? What is its phylogeny?

Many advances in evolutionary biology have emerged from asking evolutionary questions about traits important to medicine and public health, and the answers provide advances for medicine; the benefits flow in both directions. Rates of aging are heritable, so why has not selection eliminated or at least greatly slowed aging?

The strength of selection is weaker at older ages, so deleterious mutations can accumulate, and genes that give advantages in youth will be selected for even if they have pleiotropic deleterious effects later in life 9 , Populations with mostly females can have many more offspring than those with an equal sex ratio, so why are not sex ratios more often female biased? Because parents maximize their reproductive success by making offspring of whichever sex is less common, notwithstanding the penalty to group success, as R.

Fisher 11 recognized long ago. Why is reproduction sexual at all, given that nonsexual reproduction is twice as productive? This is a fascinating problem, only partly solved; most proposed solutions attribute it to the advantages of having genetically diverse offspring 12 , Reducing the genome to a single copy during meiosis seems wasteful; why not have oocytes that start with many cells? Why is cancer so persistent, and why does its prevalence increase at older ages? The evolutionary answer arises from the limits of selection in eliminating deleterious alleles, tradeoffs with the benefits of tissue repair, and genetic changes induced by pathogens Why do humans tend to have only one offspring at a time 16?

Such traits receive evolutionary analysis in life history theory 17 , Why do individuals often act in ways that decrease their own survival and reproduction? One reason is that such actions can increase the reproductive success of relatives who have identical genes 19 , Yet another is that our dietary and exercise preferences were shaped in environments fundamentally different from those common now What are the evolutionary reasons for capacities for pain, fever, and negative emotions?

Although painful and costly, they are adaptive responses that evolved in conjunction with regulatory mechanisms that express them in situations where they are useful 23 , New progress is also made possible by availability of vast amounts of genetic data and associated new methods for generating and analyzing DNA sequence and gene expression data. This is perhaps most obvious in our new ability to use genetic information to trace phylogenies of species, subpopulations, and genealogies of individuals 4.

New data and methods also allow estimation of the strength of selection acting at a given locus, allowing us to test hypotheses about selection in humans 29 , For example, strong signals of selection surround the locus of the alcohol dehydrogenase gene in Southeast Asians It is also now possible to test evolutionary theories about differences in selection acting on genes derived from paternal and maternal sources, as in the case of imprinted genes Accurate measurements of mutation accumulation have also become a reality 33 ; this might enable us to address long-standing questions about the consequences of mutation accumulation or the load of mutations We are only beginning to discover the many ways that genetic data can be used to generate and test evolutionary hypotheses and the ways that evolutionary theory can guide genetic studies and help to interpret unexpected results Increasing distance from 19th-century theories of degeneration and 20th-century eugenics makes it easier to recognize the value of modern evolutionary applications in helping individual patients.

In the early 20th century, evolutionary approaches to health emphasized eugenics, supposed racial superiority, and fears of degeneration, exploited by the Third Reich When Nazi horrors were publicized at the end of World War II, scientific publications on evolution and medicine ceased suddenly Although associations linger from previous links to eugenics, repudiation of such social policies is now so widely shared that it is easier to recognize the ways that evolutionary biology can help us understand diseases.

New evolutionary approaches to medicine are almost entirely unconnected with these earlier movements. Modern approaches tend to distance themselves actively from concerns about races and the species. Instead, they focus on ways that evolutionary biology can help to solve medical problems of individuals and meet the public health needs of communities Finally, evolutionary approaches are growing in medicine thanks to new publications and broader education of physicians and researchers.

Controversy about teaching evolution in public schools continues to inhibit evolution education, but it also has stimulated interest in many of the best students Several recent books on evolutionary approaches to medicine 25 , 27 , 28 , 39 , 40 have given rise to many new undergraduate courses on the topic, and recent international conferences have brought together those working in related areas, with predictable synergy 26 , 41 , Despite this progress, few physicians and medical researchers have had a formal course in evolutionary biology, and even fewer have had a chance to learn specific applications in medicine and public health through a course in evolutionary medicine.

Many have never even been exposed to the necessity of finding evolutionary and proximate explanations. Twenty-two leading scientists, physicians, and medical educators met five times from to to recommend scientific foundations for future physicians Instead of specific courses, they recommend education that results in eight competencies that should be mastered by students entering medical education E 1—8 and eight more for students in the course of medical education M 1—8.

E 1—7 correspond roughly to mathematics, scientific methods, physics, chemistry, biochemistry, cell biology, physiology, and facultative adaptations to internal and external changes. E8 is about evolutionary biology. As far as we are aware, this is the first recommendation from a major medical education body that physicians need to master evolutionary biology. The specific wording seems to emphasize phylogeny and phenomena at the level of the species and above, however, some especially important medical applications involve how selection shaped traits that allow individuals to adapt to their environments and the role of evolutionary factors other than selection.

A more inclusive global competency could be phrased: The areas E 1—7 are established components of premedical education, so much previous thought has gone into how they can best be taught, augmented by those in the AAMC-HHMI report. Evolutionary biology, however, is just now being recognized as a basic science for medicine.

Encyclopedia of Evolutionary Biology

Only a few papers address the issues. This article is an attempt by a diverse group of scientists to address the question systematically. Our suggestions are based on discussions by three overlapping groups of authors. Some of us spent — at the Berlin Institute for Advanced Study working together on evolutionary applications in medicine and optimal education strategies. Four others had extensive discussions in the course of organizing the Sackler Colloquium. Finally, four others presented papers at the colloquium on topics related to the role of evolution in medical education. Our opinions are, of course, diverse.

This article summarizes major areas of agreement and it attempts to clarify some issues on which opinions differ.

New Research In

We recognize that evolution is of equal importance for other health professions, such as nursing, and that it is especially important for public health. However, because somewhat different issues arise for each field, we decided to limit our recommendations here to the field of medicine. Better education about evolutionary biology and its applications in medicine will have substantial benefits for physicians, their patients, public health workers, researchers, and other health professionals.

This conclusion is supported by other articles in this colloquium and by explanatory material below in association with specific recommendations. Much of this education needs to be provided or initiated before beginning formal medical studies. Like mathematics, chemistry, genetics, and the study of biological mechanisms proximate biology , evolutionary biology is a basic science that should be taught before medical school.

The evolution content in introductory biology courses is insufficient; specialized undergraduate courses will be important. We hold varying opinions about whether to recommend general overview courses or courses specialized to the needs of future physicians. All agree that substantial evolution education is essential. Some aspects of evolutionary biology need to be taught as a part of the medical curriculum, despite the practical challenges. The medical curriculum is already overly full. However, medically relevant principles of evolutionary biology need to be taught during professional school, just as they are for other basic sciences such as anatomy, genetics, and physiology.

Evolutionary biology is a unifying principle that provides a framework for organizing medical knowledge from other basic sciences. Attaining a deep understanding of this general framework is a worthy learning objective, because much of the power of evolutionary thinking in medicine comes from its ability to foster integrative thinking about our bodies as products of evolutionary processes.

The relevance of evolutionary biology in medical education is by no means universally recognized. Medical school deans and other educators often ask for evidence that knowledge about evolutionary biology will improve the effectiveness of health-care professionals. A simple response is to cite direct applications. For instance, doctors need to understand the evolution of antibiotic resistance, methods for tracing pathogen phylogenies, how selection shaped mechanisms that regulate protective responses such as pain and fever, and the intimate connections between evolution, environment, and diseases of aging.

However, limiting the discussion to such direct applications sells short the utility of evolutionary biology in medicine. Much basic science education in medicine is required, not because it has direct daily applications, but because it is essential for understanding the body and disease. For instance, most medical schools provide an extensive course on developmental biology because understanding how a zygote develops into an adult organism is an important foundation for understanding the body in general and deviations related to disease.

Understanding how natural selection and other evolutionary processes have shaped the body and its components across evolutionary time is equally valuable. Like developmental biology, it describes patterns of development that explain why the body is the way it is and why certain aspects leave us vulnerable to diseases. So far, however, no medical school teaches evolutionary biology as a basic science comparable to embryology. The large-scale structure of evolutionary applications in medicine can be organized into 10 areas by intersecting the two subfields of evolutionary biology phylogeny and adaptation with five different targets of selection: Some of these areas are well developed and extensively taught.

For instance, population genetics is the foundation for all evolutionary approaches to disease, and phylogenetic methods are widely applied to pathogen evolution. Others are less well developed. For instance, asking questions about why selection has left the body vulnerable to disease is a newer enterprise that offers methodological challenges, and opportunities for deeper understanding 40 , 49 , General recommendations like those above provide a foundation for more specific suggestions for about what would be taught, when, and how.

We follow this same format, expanding on occasion to illustrate how physicians who master specific learning objectives will practice superior medicine. The wording could lead some to think that mutations exist to speed evolution or that the evolutionary explanation for maintained genetic variation is well understood, when it is actually an issue of intensive study in evolutionary biology, as illustrated by articles by Valle and Eyre-Walker 51 and Houle 52 in this colloquium.

Variation is only the raw material; selection does the work, and drift brings added complications. Also, although the success of populations is important, one of the great achievements of 20th-century evolutionary biology is recognition that selection generally acts to maximize benefits to individuals and their genes, not species or populations 53 , Neither of these learning objectives focuses explicitly on issues of bodily adaptation and maladaptation that are crucial for medicine.

More detailed learning objectives for evolutionary biology would make them more similar to those for other basic sciences. We recognize that our opinions are no substitute for a representative body of experts convened to address these issues; nonetheless, they may be useful. Demonstrate an understanding of how natural selection shapes traits in organisms. Grasping how selection works turns out to be quite difficult, in part because it requires replacing intuitive thinking about species-typical normal types with population thinking that views a species as a collection of genetically diverse individuals.

It also requires recognizing how evolutionary explanations are different from proximate explanations; instead of describing structures and mechanisms, they describe how a process changes the distribution of characteristics of a population over the generations. Describe how the beaks of the many species of finches of the Galapagos have come to be well-matched to the usual foods of each species and the evidence that supports your thesis.

  1. Evolutionary Applications.
  2. ?
  3. ;
  4. Behavioral Finance (Wiley Finance).
  5. All Hallows Eve;

Describe the differences between human and chimpanzee teeth and guts and the evolutionary forces that are likely responsible. The comprehension of these relations, besides being prerequisite for the understanding of biological evolution, is basic for the formation of citizens' responsibility for the environment, of which they feel themselves an integral part, and not only a passive and alienated object.

The question of language is widely discussed in the literature. Both film and written accounts, in an attempt to simplify concepts for the lay public, often use language that tends to reinforce previous misconceptions. The prevalence of vernacular misconceptions is certainly not surprising, since many scientific words like "adapt", "adaptation" and "fitness" are used in day-to-day language but carry meanings that are quite different from their meanings in the context of evolution Bishop and Anderson, ; Alters and Nelson, The figurative language, typical of abstract conceptions, contrasts with the more precise language of concrete specificity, which is less prone to figurative license.

While expert biologists easily recognize the shift from one frame of reference to another, it is possible that novices do not, and that this may be one of many reasons why the particular conceptual confusions noted above persist Moore et al. In conclusion, the pre-conceptions and difficulties mentioned above over-simplify the complexity of nature, and seem to be widely spread in several parts of the world, probably because these naive ideas seem logical and easy to understand, i.

The unsuitability of the didactic materials available to them was mentioned by the teachers in Brasilia as one of the difficulties faced by them. Several authors have assessed how textbooks deal with topics related to evolutionary biology in several parts of the world, and found that, in many cases, the textbooks analyzed not only fail to address student's difficulties, but also do not even constitute a good resource for traditional teaching Aleixandre, ; Swarts et al. In the US, where the exposition of evolutionary biology theory in secondary-level biology textbooks has been adversely affected for many years due to the influence of a nonscientific segment of public opinion, a marked increase has occurred in the role played by evolution in the generation of textbooks published during the s Moody, In Brazil, the "National Program of Didactic Books", led by the Ministry of Education, led to a significant improvement in the quality of books used in Fundamental Education Bizzo, However, the material used in Secondary Education has still not been the object of extensive analysis, even though some content of evolutionary biology has already been analyzed separately Bizzo, A deeper analysis of what occurs in Brazil in secondary education material would be extremely opportune, since the knowledge of the qualities and failures of textbooks currently used would help publishing companies to improve them.

The covering of Biology in the curriculum seems to be a problem not only in Brazil, but in other countries as well. According to Barbera et al. In Brazil, the curricular parameters developed by the Ministry of the Education recommend that the areas of ecology and evolution serve as "trans-disciplinary subjects" that permeate all the other contents of biology.

However, in the practice, evolutionary biology is generally taught at the end of 3rd year of secondary education, for which reason such knowledge often does not reach the classroom. Another problem related to curriculum is the sequence in which the contents are presented to pupils. It is widely acknowledged that evolution and Darwinian model of natural selection play a central role in modern biology.

At the same time, it has been suggested that the topic should be dealt with in the later grades, owing to the difficulties encountered, for instance, by the general lack of a sound knowledge of related topics such as genetics. The contradiction between the importance of the issue and its difficulties has created a controversy in Spain Aleixandre, and has also been already discussed in a Brazilian context Bizzo, Certainly, this is an important issue interlaced with those we had previously reviewed.

A concern with the quality of education in evolution exists in several parts of the world, including Brazil. Thus, there exist diverse proposals for dealing with the previously discussed problems, some of which will be presented below, with the objective of aiding discussions aimed at the improvement of the teaching of evolutionary biology.

There are three complementary approaches to this program that in certain respects have already been in progress in Brazil, but are in different stages of maturity. The first is the continuous training of school teachers, by supporting courses and workshops that will be rewarded by professional advancement.

The second relates to the revision and reinforcement of the curricula of Sciences, and Biology in particular, aimed at improving, in a practical way, the curricular program of the Brazilian Ministry of Education. Finally, the continuity of the National Program of Textbooks is of utmost importance, with the inclusion of the analysis of books used in the secondary education.

The courses planned for the training of school teachers would have two main objectives. First, in terms of contents, the formation of teachers must include the identification of their previous conceptions, the conceptual change needed, and the update of that knowledge. On the other hand, it is necessary to provide the instruments of instruction for these teachers in terms of strategies for teaching, such as the question of the didactic material, of the language, and of the time available in classroom for dealing with the discipline.

The recognition of the misconceptions of teachers about the evolutionary process is necessary, given the strong possibility that several of them, unconsciously, use Lamarckist reasoning in explaining the biological evolution. That is, for those who want to change student's naive concepts, the first step is to understand them Bishop and Anderson, In order to assess the student's understanding of natural selection, Anderson et al.

An activity like this, applied on the first day of the course, could be the starting point for recognizing the misconceptions of the teachers and, at the same time, it would illustrate something that they could develop later in their own classrooms. Suggestions for teaching strategies usually have been attempts to promote conceptual change Jensen and Finley, , and the basic conditions required for this kind of change were outlined by Posner et al.

The first condition is met when the learner becomes dissatisfied with his or her current understanding of some event. The students should experience a form of cognitive disequilibrium, in that they can not rationally explain some event with their current understanding. The second condition requires that the students have a meaningful understanding of at least some newly presented information.

The third condition is met when the students are able to judge the new information as plausible. If the new information does not achieve some degree of fit into a student's existing understanding, it is likely to be rejected. The fourth and final condition is that the students must be able to use the new understanding in fruitful ways. After all four conditions have been met, a student hopefully has learned that the new understanding has more utility than the old and is thus worth retaining.

Attempts at conceptual change have usually been based on instructional materials, discussions and the use of historically valid ideas Bizzo, Jensen and Finley developed and tested a very interesting, historically rich, teaching technique for biological evolution, and their data show that if instruction recapitulates events in the development of the Darwinian theory of evolution by natural selection in a way that meets the conditions for conceptual change, then students replace their initial conceptions with a more Darwinian conception.

The education in Natural Sciences provides room for the expression of spontaneous explanations by the pupils, and for those derived from several systems of explanations. The opposition and evaluation of different explanations favors the development of a reflexive, investigative and critical posture, of no- a priori acceptance of ideas and information. It makes possible the perception of the limits of each explicative model, including the scientific ones, leading to the construction of autonomy of thought and action.

It is very important that, in the training of teachers, attention is paid to the use of the language Moore et al. Teachers and students usually construct a code among themselves that is established in the classroom, in such a way that the direct participants seem to understand each other, regarding the plasticity of language used, but which would not be clear to outsiders. Bizzo detected this system of shared meanings in the context of the classroom in relation to evolutionary discourse.

So, if the teacher has a clear understanding of the difference between the meanings of some scientific terms in relation to their daily use, then he or she can make it possible for the pupils to capture correctly the meaning of such terms as "adaptation" and "fitness".

A good suggestion for exploring this subject is the essay by Gould entitled "Darwin's Dilemma: The question of the time devoted to teaching evolution, as well as the distribution of its contents in various places in the curriculum, is perhaps a little more complicated. The recommendations from the MEC for secondary education PCN, emphasize the importance of integrating knowledge from several biological areas, since the perception of the basic unit of the life, recognizing its vast diversity, has a complexity without parallel in all science However, it is difficult to reach these objectives, since there are no concrete proposals for the organization and the treatment of the curricular contents of evolutionary biology at each level of education.