493 General trends in world biogeographic literature: A preliminary bibliometric analysis Revista Brasileira de Entomologia 52(4): 493-499, dezembro 2008 Juan J. Morrone1 & Jos�� C. Guerrero2 Scientific publications represent a quantitative measure for the basic research activity in a given field. Bibliometric studies have been published in recent years focusing on the performance of particular areas, with varied temporal and geographical foci (e.g., Garg & Pahdi 2002 Zhu et al. 2004 Ferner & Aronson 2005 Zorzetto et al. 2006). Two recent studies (Riddle & Haffner 2004 Posadas & Donato 2007) have General trends in world biogeographic literature: A preliminary bibliometric analysis 1Museo de Zoolog��a ���Alfonso L. Herrera���, Departamento de Biolog��a Evolutiva, Facultad de Ciencias, Universidad Nacional Aut��noma de M��xico (UNAM), Apdo. postal 70-399, 04510 Mexico, D.F., Mexico. jjm@hp.fciencias.unam.mx. 2Departamento de Biolog��a Animal, Facultad de Ciencias, Universidad de M��laga (UMA), 29071 M��laga, Spain. jcguerrero@uma.es. ABSTRACT. General trends in world biogeographic literature: A preliminary bibliometric analysis. Records with the search string biogeograph* were collected from the Science Citation Index (SCI). A total of 3456 records were downloaded for the 1945-2006 period from titles of articles and reviews, and 10,543 records were downloaded for 1991-2006, taking into consideration also abstracts and keywords. Temporal trends of publications, geographical and institutional distribution of the research output, authorship, and core journals were evaluated. There were as many as 122 countries carrying out biogeographic research in the most recent period, USA is the top producing country, followed by the United Kingdom, Australia, France, Germany, Spain, and Canada. There were 17,493 authors contributing to the field. During 1991-2006 there were 4098 organizations with authors involved in biogeographic research institutions with higher number of papers are the Natural History Museum (United Kingdom), the University of California, Berkeley (USA), the Museum National d���Histoire Naturelle (France), the Universidad Nacional Aut��noma de M��xico (Mexico), the American Museum of Natural History (USA) and the Russian Academy of Sciences (Russia). Research articles are spread over a variety of journals, with the Journal of Biogeography, Molecular Phylogenetics and Evolution, Molecular Ecology, and Biological Journal of the Linnean Society being the core journals. From 28,759 keywords retrieved those with the highest frequency were evolution, phylogeny, diversity, mitochondrial DNA, pattern(s), systematics, and population(s). We conclude that publications on biogeography have increased substantially during the last years, especially since 1998. The preferred journal for biogeographic papers is the Journal of Biogeography. Most frequent keywords seem to indicate that biogeography fits well within both evolutionary biology and ecology, with molecular biology and phylogenetics being important factors that drive their current development. KEYWORDS. Biogeography publications journals scientometrics Science Citation Index. RESUMEN. Tendencias generales en la literatura biogeografica mundial: un an��lisis bibliom��trico preliminar. Se recolectaron registros con la palabra biogeograph* a partir del Science Citation Index (SCI). Se obtuvo un total de 3456 registros para el periodo 1945-2006, a partir de t��tulos de art��culos y revisiones y 10,543 registros para 1991-2006, tomando en cuenta tambi��n res��menes y palabras clave. Se evaluaron las tendencias temporales y geogr��ficas de las publicaciones, adem��s de la distribuci��n institucional de la investigaci��n en el ��rea, autor��a y revistas principales. Durante 1945-2006 se publicaron 3456 art��culos de biogeograf��a cuando la b��squeda para 1991-2006 se expandi�� para buscar el tema en palabras claves y res��menes, se recuperaron 10,543 registros. Hubo 122 pa��ses desarrollando investigaci��n en biogeograf��a en el periodo m��s reciente, los Estados Unidos de Am��rica fueron el pa��s principal, seguidos del Reino Unido, Australia, Francia, Alemania, Espa��a y Canad��. 17,493 autores contribuyeron a la biogeograf��a. Durante 1991-2006 hubo 4098 instituciones con autores desarrollando investigaci��n en el ��rea las que poseen un n��mero mayor de art��culos fueron el Natural History Museum (Reino Unido), la University of California, Berkeley (Estados Unidos de Am��rica), el Museum National d���Histoire Naturelle (Francia), la Universidad Nacional Aut��noma de M��xico (M��xico), el American Museum of Natural History (Estados Unidos de Am��rica) y la Academia Rusa de Ciencias (Rusia). Los art��culos de investigaci��n se hayan repartidos en una variedad de revistas, siendo las principales el Journal of Biogeography, Molecular Phylogenetics and Evolution, Molecular Ecology y Biological Journal of the Linnean Society. A partir de 28,759 palabras claves, aquellas con mayor frecuencia fueron evoluci��n, filogenia, diversidad, DNA mitocondrial, patr��n (patrones), sistem��tica y poblaci��n(es). Concluimos que las publicaciones en biogeograf��a se han incrementado sustancialmente durante los ��ltimos a��os, en especial a partir de 1998. La revista preferida para art��culos biogeogr��ficos es el Journal of Biogeography. Las palabras claves m��s frecuentes indican que la biogeograf��a cabe adecuadamente tanto en la biolog��a evolutiva como en la ecolog��a, siendo la biolog��a molecular y la sistem��tica filogen��tica los factores que conducen su desarrollo actual. PALABRAS CLAVE. Biogeograf��a bibliometr��a publicaciones revistas cientimetr��a Science Citation Index. given us some insights into the evolution and dynamics of biogeography. We think that a worldwide analysis focused on biogeographical articles published in scientific journals may help elucidate how the field is structured. We analyze the development of world production and authorship on biogeography, in order to assess quantitatively several features: temporal trends of publications, geographical

494 Morrone et al. Revista Brasileira de Entomologia 52(4): 493-499, dezembro 2008 and institutional distribution of research output, authorship, and core journals. METHODS Data for the analysis were collected from the Science Citation Index (SCI), a comprehensive data base covering scientific journals, published by Thomson Scientific, Philadelphia, USA. We downloaded two data sets, both restricting our search to articles and reviews, and omitting letters, book reviews, and other minor contributions. The first one consisted of 3456 records from 1945-2006 using the search string biogeograph* in their titles, which was used to estimate the general trend in the annual growth of publications. The second data set, consisting of 10,543 records, was compiled for 1991-2006, period for which keywords and abstracts are also available for the articles contained in SCI. It was used to analyse the geographical and institutional distribution of research output, authorship, and journals during the most recent period. In addition to Science Citation Index, we used software Endnote (Thomson ISI ResearchSoft 1998-2003) for information extraction and processing. RESULTS Temporal trends of publications on biogeography. During 1945-2006 a total of 3456 publications on biogeography was published (Fig. 1), representing an average of 56 publications per year. The growth seems relatively smooth, however, more than half (53.50%) of these publications has been published during the last nine years (1998-2006), with the highest number (246, 7.1181%) in 2006. When the search for the 1991-2006 allowed to look for the subject additionally in keywords and abstracts, a total of 10,543 of records was retrieved, which show a clearer trend to increase in the last years (Fig. 2). Considering that the complete data base for 1945-2006 includes 37,739,815 records, 3456 represents a 0.009% of publications in biogeography, whereas for the second search (1991-2006), for the 18,500,729 records available, 10,453 represents a 0.056% of biogeographic articles. Geographical distribution of research output. During 1945- 2006 there have been as many as 122 countries carrying out biogeographic research. In the most recent period (Table I), USA is the top producing country, followed by the United Kingdom, Australia, France, Germany, Spain, and Canada. Anglo-speaking countries are the three first ones, although Fig. 1. Number of publications (1946-2006) with biogeograph* in their titles. Fig. 2. Number of publications (1991-2006) with biogeograph* in their titles (open squares), and also considering keywords and abstracts (black squares).