DOI: 10.1126/science.1061967 , 2248 (2001); 293Science et al.James F. Gillooly,Effects of Size and Temperature on Metabolic Rate www.sciencemag.org (this information is current as of December 22, 2007 ):The following resources related to this article are available online at http://www.sciencemag.org/cgi/content/full/sci;294/5546/1463 A correction has been published for this article at: http://www.sciencemag.org/cgi/content/full/293/5538/2248version of this article at: including high-resolution figures, can be found in the onlineUpdated information and services, http://www.sciencemag.org/cgi/content/full/293/5538/2248/DC1 can be found at: Supporting Online Materialfound at: can berelated to this articleA list of selected additional articles on the Science Web sites http://www.sciencemag.org/cgi/content/full/293/5538/2248#related-content http://www.sciencemag.org/cgi/content/full/293/5538/2248#otherarticles, 3 of which can be accessed for free: cites 10 articlesThis article 231 article(s) on the ISI Web of Science. cited byThis article has been http://www.sciencemag.org/cgi/content/full/293/5538/2248#otherarticles 34 articles hosted by HighWire Press; see: cited byThis article has been http://www.sciencemag.org/cgi/collection/physiologyPhysiology : subject collectionsThis article appears in the following http://www.sciencemag.org/about/permissions.dtl in whole or in part can be found at: this articlepermission to reproduce of this article or about obtaining reprintsInformation about obtaining registered trademark of AAAS. is aScience2001 by the American Association for the Advancement of Science; all rights reserved. The title CopyrightAmerican Association for the Advancement of Science, 1200 New York Avenue NW, Washington, DC 20005. (print ISSN 0036-8075; online ISSN 1095-9203) is published weekly, except the last week in December, by theScience on December 22, 2007 www.sciencemag.orgDownloaded fromOur study takes advantage of large changes inhabitat fragmentation and accurate maps andsamples over the same period, enabling us toshow the importance of habitat patches inwild populations as avenues for dispersal.The northern genes have leapfrogged throughhundreds of forest fragments in a period of 20years, demonstrating the use of steppingstone patches of forest by red squirrels. Thesefindings suggest that where a network ofstepping stones is available within a criticaldispersal distance, gene flow can be veryrapid through highly fragmented landscapes.It also indicates that human-made changesaffecting the connectivity of a landscape canresult in changes in genetic structure, notonly in the area of habitat change but inpopulations hundreds of kilometers from thesite of habitat change.References and Notes1. T. M. Caro, M. K. Laurenson, Science 263, 485 (1994).2. R. Lande, S. Shannon, Evolution 50, 434 (1996).3. M. Bevers, C. H. Flather, Theor. Pop. Biol. 55,61(1999).4. N. Haddad, Conserv. Biol. 14, 738 (2000).5. J. Gurnell, P. W. W. Lurz, Eds., The Conservation of RedSquirrels, Sciurus vulgaris L. (Peoples Trust for Endan-gered Species, London, 1997).6. P. W. W. Lurz, thesis, University of Newcastle, New-castle-upon-Tyne, UK (1995).7. 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Morton, and S.Hewitt for their personal support of the project.Funded by the University of Newcastle-upon-Tyne.16 May 2001; accepted 9 August 2001Effects of Size and Temperatureon Metabolic RateJames F. Gillooly,1* James H. Brown,1,2Geoffrey B. West,2,3Van M. Savage,2,3Eric L. Charnov1We derive a general model, based on principles of biochemical kinetics andallometry, that characterizes the effects of temperature and body mass