title: Geographical and temporal body size variation in a reptile: roles of sex, ecology, phylogeny and ecology structured in phylogeny.
abstract: Geographical body size variation has long interested evolutionary biologists, and a range of mechanisms have been proposed to explain the observed patterns. It is considered to be more puzzling in ectotherms than in endotherms, and integrative approaches are necessary for testing non-exclusive alternative mechanisms. Using lacertid lizards as a model, we adopted an integrative approach, testing different hypotheses for both sexes while incorporating temporal, spatial, and phylogenetic autocorrelation at the individual level. We used data on the Spanish Sand Racer species group from a field survey to disentangle different sources of body size variation through environmental and individual genetic data, while accounting for temporal and spatial autocorrelation. A variation partitioning method was applied to separate independent and shared components of ecology and phylogeny, and estimated their significance. Then, we fed-back our models by controlling for relevant independent components. The pattern was consistent with the geographical Bergmann's cline and the experimental temperature-size rule: adults were larger at lower temperatures (and/or higher elevations). This result was confirmed with additional multi-year independent data-set derived from the literature. Variation partitioning showed no sex differences in phylogenetic inertia but showed sex differences in the independent component of ecology; primarily due to growth differences. Interestingly, only after controlling for independent components did primary productivity also emerge as an important predictor explaining size variation in both sexes. This study highlights the importance of integrating individual-based genetic information, relevant ecological parameters, and temporal and spatial autocorrelation in sex-specific models to detect potentially important hidden effects. Our individual-based approach devoted to extract and control for independent components was useful to reveal hidden effects linked with alternative non-exclusive hypothesis, such as those of primary productivity. Also, including measurement date allowed disentangling and controlling for short-term temporal autocorrelation reflecting sex-specific growth plasticity.
authors.affiliation: Departamento de Biogeografía y Cambio Global, Museo Nacional de Ciencias Naturales, Madrid, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Aragón
authors.affiliation: Departamento de Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias Naturales, Madrid, Spain; Université de Lausanne, Department of Ecology and Evolution (DEE), Biophore, Lausanne, Switzerland; Instituto Pirenaico de Ecología (IPE-CSIC), Avenida Regimiento de Galicia s/n, Jaca, Spain; Fundación Araid, Edificio Pignatelli, Zaragoza, Spain.
authors.forename: Patrick S
authors.initials: PS
authors.lastname: Fitze
mesh_terms: D000818:Animals; D005075:Biological Evolution; D049628:Body Size; D052284:Clutch Size / Q000235:genetics*; D017753:Ecosystem; D005260:Female; D056084:Genetic Fitness / Q000235:genetics*; D014644:Genetic Variation; D008116:Lizards / Q000145:classification / Q000235:genetics*; D008297:Male; D008954:Models, Biological; D010802:Phylogeny; D012098:Reproduction; D012737:Sex Factors; D062211:Spatio-Temporal Analysis; D013696:Temperature
references.citation: BMC Evol Biol. 2008 Feb 27;8:68
references.pmid: 18304333
references.citation: J Evol Biol. 2005 Nov;18(6):1559-74
references.pmid: 16313468
references.citation: Biol Rev Camb Philos Soc. 2011 May;86(2):531-41
references.pmid: 21070587
references.citation: Oecologia. 2010 Sep;164(1):13-23
references.pmid: 20364270
references.citation: Trends Ecol Evol. 2011 Jun;26(6):285-91
references.pmid: 21470708
references.citation: Am Nat. 2012 Jun;179(6):756-67
references.pmid: 22617263
references.citation: Ecol Lett. 2009 Mar;12(3):249-59
references.pmid: 19245587
references.citation: Theory Biosci. 2010 Dec;129(4):247-53
references.pmid: 20556544
references.citation: Am Nat. 2003 Sep;162(3):332-42
references.pmid: 12970841
references.citation: Am Nat. 2004 Dec;164(6):E168-E183
references.pmid: 29641924
references.citation: BMC Evol Biol. 2011 Nov 30;11:347
references.pmid: 22129245
references.citation: Evolution. 2011 Dec;65(12):3590-607
references.pmid: 22133228
references.citation: Proc Natl Acad Sci U S A. 2009 Mar 10;106(10):3835-40
references.pmid: 19234117
references.citation: Oecologia. 1993 Mar;95(1):30-37
references.pmid: 28313308
references.citation: Evolution. 1998 Oct;52(5):1247-1262
references.pmid: 28565378
references.citation: Evolution. 2003 Nov;57(11):2647-52
references.pmid: 14686540
references.citation: Proc Natl Acad Sci U S A. 2008 Mar 25;105(12):4792-5
references.pmid: 18344323
references.citation: Oikos. 2010 Sep 1;119(9):1387-1390
references.pmid: 26663982
references.citation: Evolution. 1997 Apr;51(2):630-632
references.pmid: 28565350
references.citation: Evolution. 2003 May;57(5):1151-63
references.pmid: 12836831
references.citation: Curr Biol. 2013 Jul 22;23(14):1320-3
references.pmid: 23831289
references.citation: Integr Comp Biol. 2004 Dec;44(6):498-509
references.pmid: 21676736