'Causa efficiens' versus 'Causa finalis': functional explanations in biology

Biology differs from most sciences in its particular way of dealing with the term ‘function’. On the one hand, questions like ‘What is the function of a trait x?’ seem to be perfectly legitimate, realizing that (most) biologists acknowledge that “function is a concept that to this day remains indispensable to biology” (Keller, 2010: 19). On the other hand functional explanations, along with intentional explanations, generally have one main disadvantage in common: they are teleological or seem to invoke a ‘causa finalis’. As a consequence, they are not in line with the scientific practice of explaining causality in terms of a ‘causa efficiens’. Moreover, they are claimed to be untestable (Hempel, 1965) and suggested to lead to storytelling in evolutionary biology (Gould and Lewontin, 1979; Buller, 2005), rather than to a sound scientific approach. As a reaction, efforts were made to demystify and/or naturalize functional explanations in biology. Two opposite approaches are generally distinguished: Historical approaches include Wright’s account of functions (Wright), proper function theory (Millikan, 1989), and the etiological approach (Perlman, 2010; Buller, 1999). Examples of a-historical accounts are the systemic approach (Cummins, 1975), goal contribution approach (Nagel, 1961; Boorse, 1976), life chances approach (Canfield, 1964; Wimsatt, 1972) and dispositional view (Bigelow and Pargetter, 1987). Both historical and a-historical approaches meet a number of problems. Above all, attempts to unify (Kitcher, 1993; Walsh, 1996), purify (Cummins & Roth, 2010) and instantiate (Griffiths, 1993) have only increased the amount of theories on functional explanations, making it even more difficult to maintain a clear view on the matter and the problems surrounding it. Attempts to introduce a pluralistic account, such as Wouters (2005), have tried to identify ways in which the term function is used in connection with the study of living organisms; trying to grasp how biologists appeal to function. Although promising, his account is lacking to certain extents, such as his central focus on intuitions as a guideline for the function debate. In this paper, attempts are made to reconcile and combine the advantages of the accounts mentioned, avoiding the problems (e.g. function/malfunction distinction, promiscuity of function-objection, causal asymmetry, function-setting history) these accounts are faced with. This paper contributes to the causality/explanation debate (in biology) in at least three ways: First, in respect to the time frame of the presentation, an overview of the existing accounts and approaches to functional explanation in biology will be given, which is missing in the literature, rendering some contemporary discussions superfluous. Second, a bottom-up, pragmatic, context-sensitive and pluralistic framework capable of dealing with functional explanation in scientific practice will be presented, guided by answers to central questions, such as ‘Are we to choose between accounts?’ and ‘Are the proposed accounts incompatible and/or excluding?’. In detail, a relational theory of biological function able to combine the historical and a-historical approaches mentioned serves as underlying guideline to fully grasp examples from actual scientific practice (i.e. molecular gene biology and systems biology). This pluralistic theory defends that the function of a state or trait is not an intrinsic property, but always stands in relation to an environment. Therefore, a trait may have different functions with respect to different environments at the same time. Third, in view of the topic of the conference, special attention will be given to the teleological character of functional explanation, addressing the scientific merits and/or pitfalls of causality-debate in terms of ‘causa finalis’

On the maximum rank of a real binary form

We show that a real homogeneous polynomial f(x,y) with distinct roots and degree d greater or equal than 3 has d real roots if and only if for any (a,b) not equal to (0,0) the polynomial af_x+bf_y has d-1 real roots. This answers to a question posed by P. Comon and G. Ottaviani, and shows that the interior part of the locus of degree d binary real binary forms of rank equal to d is given exactly by the forms with d real roots.Comment: To appear in Annali di Matematica Pura ed Applicat

Policies and Education in Latin America : From the 'competitive quality' to 'quality for the generation of bicentenary'

En América Latina la injerencia de los organismos internacionales en la política nacional constituye un fenómeno que no se puede soslayar. Se trata de una cuestión candente en el contexto actual y remite a la presencia creciente en los países de la región de una serie de papers, documentos, boletines que, generados en el seno de dichas entidades, señalan desafíos presentes y futuros que deberá atender América Latina. En el campo educativo, marcan las orientaciones de política para la región y representan discursos sobre la educación que es menester analizar críticamente. El objetivo de este trabajo es analizar una serie de ideas, recomendaciones y retóricas político-pedagógicas de los Organismos Internacionales respecto de la denominada calidad de la educación en América Latina con la intención de poner de manifiesto su productividad discursiva en tanto su incidencia está ligada a significantes que operan ordenando las disputas político-discursivas del campo educativoIn Latin America the interference of the international organisms in national politics is a phenomenon can not be ignored. This is a hot issue in the current context and refers to the growing presence countries in the region of a series of papers, documents, newsletters generated within those entities; identify challenges and future that should address Latin America. In education, mark the policy guidelines for the region and represent discourses on education that is necessary to analyze critically. The aim of this paper is to analyze a series of ideas, recommendations and political educational rhetoric of international organizations for educational quality in Latin America with the intention of highlighting their discursive productivity while its incidence is linked to significant operating ordering political disputes discursive field of educationFil: Causa, Matías. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación. Instituto de Investigaciones en Humanidades y Ciencias Sociales (UNLP-CONICET); Argentina

Magnetic polarons in Ca_(1-x)Y_xMnO_3

Experimental evidence show that in the magnetoresistive manganite Ca_(1-x) Y_xMnO_3, ferromagnetic (FM) polarons arises in an antiferromagnetic (AF) background, as a result of the doping with Yttrium. This hypothesis is supported in this work by classical Monte Carlo (MC) calculations performed on a model where FM Double Exchange (DE) and AF Superexhange (SE) compite.Comment: 3 pages, 3 figs, submitted to LAW3M conferenc

Novas tendências em marketing por causa do auge da Internet

The use of Internet has changed considerably the marketing practice. In this article the authors carry on a literature review to analyse the factors involved in the process and also the advantages, challenges and opportunities of this technology from a marketing perspective.El uso de Internet ha traído cambios considerables para la práctica del Marketing. Este artículo lleva a cabo una revisión bibliográfica donde se analizan los factores que están relacionados con el proceso de cambio así como las ventajas, desafíos y oportunidades que ofrece esta nueva tecnología desde una perspectiva del Marketing.O uso da Internet trouxe mudanças consideráveis para a prática do Marketing. Este artigo realiza uma revisão bibliográfica onde se analisam os fatores que estão relacionados com o processo de mudança assim como as vantagens, desafios e oportunidades oferecidas por esta nova tecnologia a partir de uma perspectiva de Marketing

Building Alliances: Collaboration between CAUSA and the Rural Organizing Project in Oregon

This ethnography examines the components that allow quality solidarity work to happen between organizations with leadership and constituencies that are primarily people of color and primarily white, respectively. CAUSA (an immigrant rights coalition) and the Rural Organizing Project (ROP) of Oregon have developed a working relationship over ten years that has contributed to numerous victories for immigrant and farm worker rights, as well as greater consciousness among white rural activists of what it means to provide support as anti-racist allies. Because Oregon has a relatively small population (three million), and progressive organizations tend to know each other, the relationship provides an opportunity to study how such organizations manage power and historical inequalities in a manner suited for success. Ethnographer Lynn Stephen has conducted in-depth interviews with organizational leaders and members as a way to explore the history and lessons learned from the collaborative work between the two organizations. Key findings include the importance of both in-depth and sustained dialogue around the key values of work, and staff training around the issues involved with connecting to the other organization. The organizations use these techniques to build common ground. Hence, collaborative capacity can be mobilized quickly to support each other's actions as needed

Evidence of strong antiferromagnetic coupling between localized and itinerant electrons in ferromagnetic Sr2FeMoO6

Magnetic dc susceptibility ($\chi$) and electron spin resonance (ESR) measurements in the paramagnetic regime, are presented. We found a Curie-Weiss (CW) behavior for $\chi$(T) with a ferromagnetic $\Theta = 446(5)$ K and $\mu_{eff} = 4.72(9) \mu_{B}/f.u.$, this being lower than that expected for either $Fe^{3+}(5.9\mu_{B})$ or $Fe^{2+}(4.9\mu_{B})$ ions. The ESR g-factor $g = 2.01(2)$, is associated with $Fe^{3+}$. We obtained an excellent description of the experiments in terms of two interacting sublattices: the localized $Fe^{3+}$ ($3d^{5}$) cores and the delocalized electrons. The coupled equations were solved in a mean-field approximation, assuming for the itinerant electrons a bare susceptibility independent on $T$. We obtained $\chi_{e}^{0} = 3.7$ $10^{-4}$ emu/mol. We show that the reduction of $\mu_{eff}$ for $Fe^{3+}$ arises from the strong antiferromagnetic (AFM) interaction between the two sublattices. At variance with classical ferrimagnets, we found that $\Theta$ is ferromagnetic. Within the same model, we show that the ESR spectrum can be described by Bloch-Hasegawa type equations. Bottleneck is evidenced by the absence of a $g$-shift. Surprisingly, as observed in CMR manganites, no narrowing effects of the ESR linewidth is detected in spite of the presence of the strong magnetic coupling. These results provide evidence that the magnetic order in $Sr_{2}FeMoO_{6}$ does not originates in superexchange interactions, but from a novel mechanism recently proposed for double perovskites